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Sample records for aeroassisted space transfer

  1. Optimal trajectories for aeroassisted orbital transfer

    NASA Technical Reports Server (NTRS)

    Miele, A.; Venkataraman, P.

    1983-01-01

    Consideration is given to classical and minimax problems involved in aeroassisted transfer from high earth orbit (HEO) to low earth orbit (LEO). The transfer is restricted to coplanar operation, with trajectory control effected by means of lift modulation. The performance of the maneuver is indexed to the energy expenditure or, alternatively, the time integral of the heating rate. Firist-order optimality conditions are defined for the classical approach, as are a sequential gradient-restoration algorithm and a combined gradient-restoration algorithm. Minimization techniques are presented for the aeroassisted transfer energy consumption and time-delay integral of the heating rate, as well as minimization of the pressure. It is shown that the eigenvalues of the Jacobian matrix of the differential system is both stiff and unstable, implying that the sequential gradient restoration algorithm in its present version is unsuitable. A new method, involving a multipoint approach to the two-poing boundary value problem, is recommended.

  2. Aeroassisted orbital transfer vehicle control technology

    NASA Technical Reports Server (NTRS)

    Langehough, M. A.

    1988-01-01

    The focus of this control has been to develop the control technology required to identify the sophistication required for the Aeroassisted Orbital Transfer Vehicle (AOTV) control system. An angle of attack, bank angle command control technique has been developed which uses either on-off thruster or proportional thruster. An angle of attack adaptive controller was included to minimize the reactor control system (RCS) usage due to payload center of gravity uncertainties. The guidance and control techniques were verified using a detail six degrees-of-freedom simulation. Mission sensitivity was developed for uncertainties in the entry state, mass properties, atmosphere, aerodynamic, and sensor.

  3. Computational chemistry and aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Cooper, D. M.; Jaffe, R. L.; Arnold, J. O.

    1985-01-01

    An analysis of the radiative heating phenomena encountered during a typical aeroassisted orbital transfer vehicle (AOTV) trajectory was made to determine the potential impact of computational chemistry on AOTV design technology. Both equilibrium and nonequilibrium radiation mechanisms were considered. This analysis showed that computational chemistry can be used to predict (1) radiative intensity factors and spectroscopic data; (2) the excitation rates of both atoms and molecules; (3) high-temperature reaction rate constants for metathesis and charge exchange reactions; (4) particle ionization and neutralization rates and cross sections; and (5) spectral line widths.

  4. A review of shock waves around aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Park, C.

    1985-01-01

    Aeroassisted orbital transfer vehicles (AOTVs) are a proposed type of reusable spacecraft that would be used to transport cargoes from one Earth-bound orbit to another. Such vehicles could be based on the proposed space station and used to transport commercial satellites from the space station to geostationary orbits or to polar orbits and return. During a mission, AOTVs would fly through Earth's atmosphere, thus generating aerodynamic forces that could be used for decelerating the vehicles or changing their direction. AOTV research findings were concerned with the shock-wave-induced, high-temperature airflows that would be produced around these vehicles during atmospheric flight. Special emphasis was placed on the problems of: (1) the chemical physics of multitemperature, ionizing, nonequilibrium air flows, and (2) the dynamics of the flows in the base region of a blunt body with complex afterbody geometry.

  5. A review of shock waves around aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Park, C.

    1986-01-01

    Aeroassisted orbital transfer vehicles (AOTVs) are a proposed type of reusable spacecraft that would be used to transport cargoes from one earth-bound orbit to another. Such vehicles could be based on the proposed space station and used to transport commercial satellites from the space station to geostationary orbits or to polar orbits and return. During a mission, AOTVs would fly through earth's atmosphere, thus generating aerodynamic forces that could be used for decelerating the vehicles or changing their direction. AOTV research findings were concerned with the shock-wave-induced, high-temperature airflows that would be produced around these vehicles during atmospheric flight. Special emphasis was placed on the problems of: (1) the chemical physics of multitemperature, ionizing, nonequilibrium air flows, and (2) the dynamics of the flows in the base region of a blunt body with complex afterbody geometry.

  6. Neighboring optimal guidance for aeroassisted noncoplanar orbital transfer

    NASA Technical Reports Server (NTRS)

    Naidu, D. S.

    1991-01-01

    The fuel-optimal control problem in aeroassisted noncoplanar orbital transfer is addressed. The equations of motion for the atmospheric maneuver are nonlinear and the optimal (nominal) trajectory and control are obtained. In order to follow the nominal trajectory under actual conditions, a neighboring optimum guidance scheme is designed using linear quadratic regulator theory for onboard real-time implementation. One of the state variables is used as the independent variable in preference to the time. The weighting matrices in the performance index are chosen by a combination of a heuristic method and an optimal modal approach. The necessary feedback control law is obtained in order to minimize the deviations from the nominal conditions. The results are presented to a typical aeroassisted noncoplanar orbital transfer problem.

  7. Project SPARC: Space-Based Aeroassisted Reusable Craft

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Future United States' space facilities include a Space Station in low Earth orbit (LEO) and a Geosynchronous Operations Support Center, or GeoShack, in geosynchronous orbit (GEO). One possible mode of transfer between the two orbits is an aerobraking vehicle. When traveling from GEO to LEO, the Earth's atmosphere can be used to aerodynamically reduce the velocity of the vehicle, which reduces the amount of propulsive change in velocity required for the mission. An aerobrake is added to the vehicle for this purpose, but the additional mass increases propellant requirements. This increase must not exceed the amount of propellant saved during the aeropass. The design and development of an aerobraking vehicle that will transfer crew and cargo between the Space Station and GeoShack is examined. The vehicle is referred to as Project SPARC, a SPace-based Aeroassisted Reusable Craft. SPARC consists of a removable 45 ft diameter aerobrake, two modified Pratt and Whitney Advanced Expander Engines with a liquid oxygen/liquid hydrogen propellant, a removable crew module with a maximum capacity of five, and standard sized payload bays providing a maximum payload capacity of 28,000 lbm. The aerobrake, a rigid, ellipsoidally blunted elliptical cone, provides lift at zero angle-of-attack due to a 73 deg rake angle, and is covered with a flexible multi-layer thermal protection system. Maximum dry mass of the vehicle without payload is 20,535 lbm, and the maximum propellant requirement is 79,753 lbm at an oxidizer to fuel ratio of 6/1. Key advantages of SPARC include its capability to meet mission changes, and its removable aerobrake and crew module.

  8. Fuel-optimal trajectories for aeroassisted coplanar orbital transfer problem

    NASA Technical Reports Server (NTRS)

    Naidu, Desineni Subbaramaiah; Hibey, Joseph L.; Charalambous, Charalambos D.

    1990-01-01

    The optimal control problem arising in coplanar orbital transfer employing aeroassist technology is addressed. The maneuver involves the transfer from high to low earth orbit via the atmosphere, with the object of minimizing the total fuel consumption. Simulations are carried out to obtain the fuel-optimal trajectories for flying the spacecraft through the atmosphere. A highlight is the application of an efficient multiple-shooting method for treating the nonlinear two-point boundary value problem resulting from the optimizaion procedure. The strategy for the atmospheric portion of the minimum-fuel transfer is to fly at the maximum lift-to-drag ratio L/D initially in order to recover from the downward plunge, and then to fly at a negative L/D to level off the flight so that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  9. Fuel-optimal trajectories for aeroassisted coplanar orbital transfer problem

    NASA Astrophysics Data System (ADS)

    Naidu, Desineni Subbaramaiah; Hibey, Joseph L.; Charalambous, Charalambos D.

    1990-03-01

    The optimal control problem arising in coplanar orbital transfer employing aeroassist technology is addressed. The maneuver involves the transfer from high to low earth orbit via the atmosphere, with the object of minimizing the total fuel consumption. Simulations are carried out to obtain the fuel-optimal trajectories for flying the spacecraft through the atmosphere. A highlight is the application of an efficient multiple-shooting method for treating the nonlinear two-point boundary value problem resulting from the optimizaion procedure. The strategy for the atmospheric portion of the minimum-fuel transfer is to fly at the maximum lift-to-drag ratio L/D initially in order to recover from the downward plunge, and then to fly at a negative L/D to level off the flight so that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  10. A simplified guidance algorithm for lifting aeroassist orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Cerimele, C. J.; Gamble, J. D.

    1985-01-01

    The derivation, logic, and performance of a simplified atmospheric guidance algorithm for aeroassist orbital-transfer vehicles (AOTVs) are presented. The algorithm was developed to meet the demands for an aerobraking trajectory guidance technique that was uncomplicated, easily integrated into existing trajectory programs, adaptable to a range of vehicle aerodynamic configurations, capable of performance equivalent to currently available guidance programs in compensating for dispersions in entry conditions, atmospheric conditions, and aerodynamic characteristics. The result was a hybrid lifting guidance algorithm combining the method of reference-profile generation with the method of predictor/corrector schemes. The resulting performance is good (less than 3 n.m. error from desired apogee despite uncertainties of + or - 50 percent atmospheric density, + or - 0.2 deg entry flight-path angle, or + or - 50 percent L/D. Combinations of these same dispersions with lesser magnitudes have also been successful, although performance with density 'pockets' within the atmosphere requires more analysis.

  11. Optimal aeroassisted orbital transfer with plane change using collocation and nonlinear programming

    NASA Technical Reports Server (NTRS)

    Shi, Yun. Y.; Nelson, R. L.; Young, D. H.

    1990-01-01

    The fuel optimal control problem arising in the non-planar orbital transfer employing aeroassisted technology is addressed. The mission involves the transfer from high energy orbit (HEO) to low energy orbit (LEO) with orbital plane change. The basic strategy here is to employ a combination of propulsive maneuvers in space and aerodynamic maneuvers in the atmosphere. The basic sequence of events for the aeroassisted HEO to LEO transfer consists of three phases. In the first phase, the orbital transfer begins with a deorbit impulse at HEO which injects the vehicle into an elliptic transfer orbit with perigee inside the atmosphere. In the second phase, the vehicle is optimally controlled by lift and bank angle modulations to perform the desired orbital plane change and to satisfy heating constraints. Because of the energy loss during the turn, an impulse is required to initiate the third phase to boost the vehicle back to the desired LEO orbital altitude. The third impulse is then used to circularize the orbit at LEO. The problem is solved by a direct optimization technique which uses piecewise polynomial representation for the state and control variables and collocation to satisfy the differential equations. This technique converts the optimal control problem into a nonlinear programming problem which is solved numerically. Solutions were obtained for cases with and without heat constraints and for cases of different orbital inclination changes. The method appears to be more powerful and robust than other optimization methods. In addition, the method can handle complex dynamical constraints.

  12. Aeroassisted transfer between coplanar elliptical orbits during near constant altitude coasting

    NASA Astrophysics Data System (ADS)

    Taratuta, Aba; Mishne, David; Gur, Ilana

    An aeroassisted transfer between coplanar elliptical orbits is presented. The maneuver consists of three thrust impulses and a coast flight in the atmosphere. Several control strategies for the atmospheric coast are analyzed: constant altitude coast, constant velocity glide, constant heating rate coast. For each control strategy, the optimal altitude is chosen. The criterion for the maneuver efficiency was the amount of fuel consumption for a given rotation angle, subject to a heating rate limit. The results are compared with aeroassisted multipass maneuver and aeroassisted drag-only maneuver. It was shown that the coast maneuver extends the region in which the lift-controlled aeroassisted maneuver is superior to other maneuvers. Numerical examples are presented.

  13. Nearly-grazing optimal trajectories for noncoplanar, aeroassisted orbital transfer

    NASA Technical Reports Server (NTRS)

    Miele, A.; Mease, K. D.; Lee, W. Y.

    1988-01-01

    This paper discusses aeroassisted orbital transfer maneuvers under the assumption that the terminal orbital inclinations are different. Both GEO-to-LEO and LEO-to-LEO transfers are considered in connection with a spacecraft which is controlled during the atmospheric pass via the angle of attack and the angle of bank. Within the framework of classical optimal control, the following problems are studied: the minimization of the total characteristic velocity (P1); the minimization of the time integral of the square of the path inclination (P5); and the minimization of the peak heating rate (Q1). Numerical solutions are obtained by means of the sequential gradient-restoration logarithm for optimal control problems under the conditions that, for the problem (P1), the plane change components are optimized, while for the problems (P5) and (Q1), the plane change components are kept at the levels determined for problem (P1). The engineering implications of the solutions are discussed, in order to determine the most useful solutions in the light of energy requirements and heat transfer requirements.

  14. Optimal aeroassisted coplanar orbital transfer using an energy model

    NASA Technical Reports Server (NTRS)

    Halyo, Nesim; Taylor, Deborah B.

    1989-01-01

    The atmospheric portion of the trajectories for the aeroassisted coplanar orbit transfer was investigated. The equations of motion for the problem are expressed using reduced order model and total vehicle energy, kinetic plus potential, as the independent variable rather than time. The order reduction is achieved analytically without an approximation of the vehicle dynamics. In this model, the problem of coplanar orbit transfer is seen as one in which a given amount of energy must be transferred from the vehicle to the atmosphere during the trajectory without overheating the vehicle. An optimal control problem is posed where a linear combination of the integrated square of the heating rate and the vehicle drag is the cost function to be minimized. The necessary conditions for optimality are obtained. These result in a 4th order two-point-boundary-value problem. A parametric study of the optimal guidance trajectory in which the proportion of the heating rate term versus the drag varies is made. Simulations of the guidance trajectories are presented.

  15. Gamma guidance of trajectories for coplanar, aeroassisted orbital transfer

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.

    1990-01-01

    The optimization and guidance of trajectories for coplaner, aeroassisted orbital transfer (AOT) from high Earth orbit (HEO) to low Earth orbit (LEO) are examined. In particular, HEO can be a geosynchronous Earth orbit (GEO). It is assumed that the initial and final orbits are circular, that the gravitational field is central and is governed by the inverse square law, and that at most three impulses are employed: one at HEO exit, one at atmospheric exit, and one at LEO entry. It is also assumed that, during the atmospheric pass, the trajectory is controlled via the lift coefficient. The presence of upper and lower bounds on the lift coefficient is considered. First, optimal trajectories are computed by minimizing the total velocity impulse (hence, the propellant consumption) required for AOT transfer. The sequential gradient-restoration algorithm (SGRA) is used for optimal control problems. The optimal trajectory is shown to include two branches: a relatively short descending flight branch (branch 1) and a long ascending flight branch (branch 2). Next, attention is focused on guidance trajectories capable of approximating the optimal trajectories in real time, while retaining the essential characteristics of simplicity, ease of implementation, and reliability. For the atmospheric pass, a feedback control scheme is employed and the lift coefficient is adjusted according to a two-stage gamma guidance law. Further improvements are possible via a modified gamma guidance which is more stable with respect to dispersion effects arising from navigation errors, variations of the atmospheric density, and uncertainties in the aerodynamic coefficients than gamma guidance trajectory. A byproduct of the studies on dispersion effects is the following design concept. For coplaner aeroassisted orbital transfer, the lift-range-to-weight ratio appears to play a more important role than the lift-to-drag ratio. This is because the lift-range-to-weight ratio controls mainly the minimum

  16. Approximate solutions to minimax optimal control problems for aeroassisted orbital transfer

    NASA Technical Reports Server (NTRS)

    Miele, A.; Basapur, V. K.

    1984-01-01

    The maneuver considered in the present investigation involves the coplanar transfer of a spacecraft from a high earth orbit (HEO) to a low earth orbit (LEO). HEO can be a geosynchronous earth orbit (GEO). The basic concept utilized involves the hybrid combination of propulsive maneuvers in space and aerodynamic maneuvers in the sensible atmosphere. The considered type of flight is also called synergetic space flight. With respect to the atmospheric part of the maneuver, trajectory control is achieved by means of lift modulation. The Bolza problem of optimal control is stated, and the first-order optimality conditions for this problem are given. The one-arc approach, the two-arc approach, and the three-subarc approach are discussed. Attention is given to the Chebyshev problem of optimal control, details concerning aeroassisted orbital transfer (AOT), AOT optimization problems, and numerical experiments.

  17. Minimum-fuel aeroassisted coplanar orbit transfer using lift-modulation

    NASA Technical Reports Server (NTRS)

    Mease, K. D.; Vinh, N. X.

    1983-01-01

    Minimum-fuel trajectories and lift controls are computed for aeroassisted coplanar transfer from high orbit to low orbit. The optimal aeroassisted transfer requires less fuel than the all-propulsive Hohmann transfer for a wide range of high orbit to low orbit transfers. The optimal control program for the atmospheric portion of the transfer is to fly at maximum positive L/D initially to recover from the downward plunge, and then, to fly at negative L/D to level off the flight, such that the vehicle skips out of the atmosphere with a flight path angle near zero degrees. To avoid excessive heating rates, the vehicle flies initially at high angle of attack in order to slow down higher in the atmosphere, allowing recovery from the downward plunge, which occurs subsequently using the maximum positive L/D, to take place at a lower atmospheric density, or equivalently, at a higher altitude.

  18. Minimum-fuel aeroassisted coplanar orbit transfer using lift-modulation

    NASA Astrophysics Data System (ADS)

    Mease, K. D.; Vinh, N. X.

    1983-08-01

    Minimum-fuel trajectories and lift controls are computed for aeroassisted coplanar transfer from high orbit to low orbit. The optimal aeroassisted transfer requires less fuel than the all-propulsive Hohmann transfer for a wide range of high orbit to low orbit transfers. The optimal control program for the atmospheric portion of the transfer is to fly at maximum positive L/D initially to recover from the downward plunge, and then, to fly at negative L/D to level off the flight, such that the vehicle skips out of the atmosphere with a flight path angle near zero degrees. To avoid excessive heating rates, the vehicle flies initially at high angle of attack in order to slow down higher in the atmosphere, allowing recovery from the downward plunge, which occurs subsequently using the maximum positive L/D, to take place at a lower atmospheric density, or equivalently, at a higher altitude.

  19. Minimum fuel coplanar aeroassisted orbital transfer using collocation and nonlinear programming

    NASA Technical Reports Server (NTRS)

    Shi, Yun Yuan; Young, D. H.

    1991-01-01

    The fuel optimal control problem arising in coplanar orbital transfer employing aeroassisted technology is addressed. The mission involves the transfer from high energy orbit (HEO) to low energy orbit (LEO) without plane change. The basic approach here is to employ a combination of propulsive maneuvers in space and aerodynamic maneuvers in the atmosphere. The basic sequence of events for the coplanar aeroassisted HEO to LEO orbit transfer consists of three phases. In the first phase, the transfer begins with a deorbit impulse at HEO which injects the vehicle into a elliptic transfer orbit with perigee inside the atmosphere. In the second phase, the vehicle is optimally controlled by lift and drag modulation to satisfy heating constraints and to exit the atmosphere with the desired flight path angle and velocity so that the apogee of the exit orbit is the altitude of the desired LEO. Finally, the second impulse is required to circularize the orbit at LEO. The performance index is maximum final mass. Simulation results show that the coplanar aerocapture is quite different from the case where orbital plane changes are made inside the atmosphere. In the latter case, the vehicle has to penetrate deeper into the atmosphere to perform the desired orbital plane change. For the coplanar case, the vehicle needs only to penetrate the atmosphere deep enough to reduce the exit velocity so the vehicle can be captured at the desired LEO. The peak heating rates are lower and the entry corridor is wider. From the thermal protection point of view, the coplanar transfer may be desirable. Parametric studies also show the maximum peak heating rates and the entry corridor width are functions of maximum lift coefficient. The problem is solved using a direct optimization technique which uses piecewise polynomial representation for the states and controls and collocation to represent the differential equations. This converts the optimal control problem into a nonlinear programming problem

  20. Aeroassist Key to Returning From Space and the Case for AFE

    NASA Technical Reports Server (NTRS)

    Williams, Louis J.; Putnam, Terrill W.; Morris, Robert

    1997-01-01

    The Aeroassist Flight Experiment (AFE) is important in the development of a substantial and cost-competitive space industry. It is a research program to develop the technology base needed to design a new class of advanced entry vehicles that will play a key role in establishing a mature U.S. space presence in the next century. A dynamic and economical space program in the 21st century will include many operations involving the return of satellites, materials, and products from high Earth orbits (HEO), lunar bases, and planetary missions. The common and dominant characteristics of vehicles returning from such missions will be their very high speed as they approach the Earth. This high speed must be reduced substantially before the returning vehicle can be landed safely on Earth or placed in low Earth orbit (LEO), where the Space Shuttle operates now and the Space Station Freedom will operate in the future. LEO is a strategic that will always play a critical role in any space program. Its location just beyond earth's appreciable atmosphere can be reached from earth with the lowest cost in energy, and it is the natural and convenient spaceport location. In the next century LEO will contain a broad complex of assembly, research, repair, and production facilities. Their effective and cost-competitive use will require a class of routine workhorse transportation vehicles whose importance might be over-looked at a time when dramatic space exploration is occurring. Yet it is these vehicles, the Aeroassisted Space Transfer Vehicles (ASTV's) that will provide that solid transportation base on which a productive space industry will grow. The ASTV's will be assembled in orbit and will never return to earth's surface. They will be used to transfer people and material from high locations to LEO. They will reduce their high velocities in the outer reaches of the earth's atmosphere where aerodynamic drag will slow them to the appropriate speed for LEO. They will then maneuver out

  1. Nonlinear feedback guidance law for aero-assisted orbit transfer maneuvers

    NASA Technical Reports Server (NTRS)

    Menon, P. K. A.

    1992-01-01

    Aero-assisted orbit transfer vehicles have the potential for significantly reducing the fuel requirements in certain classes of orbit transfer operations. Development of a nonlinear feedback guidance law for performing aero-assisted maneuvers that accomplish simultaneous change of all the orbital elements with least vehicle acceleration magnitude is discussed. The analysis is based on a sixth order nonlinear point-mass vehicle model with lift, bank angle, thrust and drag modulation as the control variables. The guidance law uses detailed vehicle aerodynamic and the atmosphere models in the feedback loop. Higher-order gravitational harmonics, planetary atmosphere rotation and ambient winds are included in the formulation. Due to modest computational requirements, the guidance law is implementable on-board an orbit transfer vehicle. The guidance performance is illustrated for three sets of boundary conditions.

  2. Catalytic surface effect on ceramic coatings for an aeroassisted orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Steward, D. A.; Leiser, D. B.

    1984-01-01

    Surface catalytic efficiencies of glassy coatings were determined from a reaction boundary layer computation and arc-jet data. The catalytic efficiencies of the various coatings examined are discussed in terms of their reaction-rate constants. These constants are a function of the wall temperature (1290 K to 2000 K). In addition, the advantage of a thermal protection system for a bent biconic, aeroassisted orbital transfer vehicle with a low surface catalytic efficiency is discussed.

  3. Spatial statistical point prediction guidance for heating-rate-limited aeroassisted orbital transfer

    NASA Astrophysics Data System (ADS)

    Ghosh, Pradipto; Conway, Bruce A.

    2015-06-01

    Feedback control of constrained non-linear dynamical systems satisfying a certain optimality criterion and meeting a specified transfer objective in the state space is recognized as one of the most challenging problems in control theory. One approach to computing optimal feedback policies is the dynamic programming route of numerically solving the Hamilton-Jacobi-Bellman (HJB) partial differential equation directly. In this paper an alternate and more tractable dynamic programming approach, the optimal feedback synthesis method, is utilized. The effectiveness of this method is demonstrated through an explicit guidance scheme for the heating-rate-constrained maneuver of an Aeroassisted Transfer Vehicle (AOTV). In optimal feedback synthesis, a feedback chart is constructed from a family of open-loop extremals, thus ensuring optimality with respect to any initial condition in the family. This paper presents a solution to the AOTV optimal feedback synthesis problem using the Gaussian process spatial prediction method of universal kriging. A closed-form expression for a near-optimal guidance law is derived. Its performance is found to be very promising; initial atmospheric entry errors due to simulated thruster misfiring are seen to be accurately corrected while the algebraic state-inequality constraint is closely respected.

  4. System technology analysis of aeroassisted orbital transfer vehicles: Moderate lift/drag (0.75-1.5). Volume 2: Supporting research and technology report, phase 1 and 2

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Technology payoffs of representative ground based (Phase 1) and space based (Phase 2) mid lift/drag ratio (L/D) aeroassisted orbit transfer vehicles (AOTV) were assessed and prioritized. The methodology employed to generate technology payoffs, the major payoffs identified, the urgency of the technology effort required, and the technology plans suggested are summarized for both study phases. Technology issues concerning aerodynamics, aerothermodynamics, thermal protection, propulsion, and guidance, navigation and control are addressed.

  5. Aerodynamic characteristics of generalized bent biconic bodies for aero-assisted, orbital-transfer vehicles

    NASA Technical Reports Server (NTRS)

    Davies, C. B.; Park, C.

    1983-01-01

    A method was developed to generate the surface coordinates of body shapes suitable for aeroassisted, orbital-transfer vehicles (AOTVs) by extending bent biconic geometries. Lift, drag, and longitudinal moments were calculated for the bodies using Newtonian flow theory. These techniques were applied to symmetric and asymmetric aerobraking vehicles, and to an aeromaneuvering vehicle with high L/D. Results for aerobraking applications indicate that a 70 deg, fore half cone angle with a spherically blunted nose, rounded edges, and a slight asymmetry would be appropriate. Moreover, results show that an aeromaneuvering vehicle with L/D 2.0, and with sufficient stability, is feasible.

  6. Electron-impact vibrational excitation rates in the flow field of aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Lee, J.-H.

    1985-01-01

    This paper examines the vibrational excitation rate processes expected in the flow field of aeroassisted orbital transfer vehicles (AOTVs). An analysis of the multiple-quantum vibrational excitation processes by electron impact is made to predict the vibrational excitation cross sections, rate coefficients, and relaxation times which control vibrational temperature. The expression for the rate of electron-vibration energy transfer is derived by solving the system of master equations which account for the multiple-level transitions. The vibrational excitation coefficients, which are the prerequisite physical quantities in solving the obtained vibrational equation, are calculated based on the theoretically predicted cross sections. These cross sections are obtained from quantum mechanical calculations, based on the concept that vibrational excitation of molecules by electron impact occurs through formation of an intermediate negative ion state. Finally, the modified Landau-Teller-type rate equation, which is suitable for the numerical calculations for the AOTV flow fields, is suggested.

  7. Basic Governing Equations for the Flight Regimes of Aeroassisted Orbital Transfer Vehicles

    NASA Technical Reports Server (NTRS)

    Lee, Jong-Hun

    1985-01-01

    The basic governing equations for the low-density, high-enthalpy flow regimes expected in the shock layers over the heat shields of the proposed aeroassisted orbital transfer vehicles are derived by combining and extending existing theories. The conservation equations are derived from gas kinetic principles for a four-component ionized gas consisting of neutral molecules, neutral atoms, singly ionized ions, and electrons, assuming a continuum flow. The differences among translational-rotational, vibrational, and electron temperatures are accounted for, as well as chemical nonequilibrium and electric-charge separation. Expressions for convective and viscous fluxes, transport properties, and the terms representing interactions among various energy modes are explicitly given. The expressions for the rate of electron-vibration energy transfer, which violates the Landau-Teller conditions, are derived by solving the system of master equations accounting for the multiple-level transitions.

  8. Fuel-optimal trajectories of aeroassisted orbital transfer with plane change

    NASA Astrophysics Data System (ADS)

    Naidu, D. S.

    The problem of minimization of fuel consumption during the atmospheric portion of an aeroassisted, orbital transfer with plane change is addressed. The complete mission has required three characteristic velocities, a deorbit impulse at high earth orbit (HEO), a boost impulse at the atmospheric exit, and a reorbit impulse at low earth orbit (LEO). A performance index has been formulated as the sum of these three impulses. Application of optimal control principles has led to a nonlinear, two-point, boundary value problem which was solved by using a multiple shooting algorithm. The strategy for the atmospheric portion of the minimum-fuel transfer is to start initially with the maximum positive lift in order to recover from the downward plunge, and then to fly with a gradually decreasing lift such that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  9. Fuel-optimal trajectories of aeroassisted orbital transfer with plane change

    NASA Astrophysics Data System (ADS)

    Naidu, Desineni Subbaramaiah; Hibey, Joseph L.

    1989-06-01

    The problem of minimization of fuel consumption during the atmospheric portion of an aeroassisted, orbital transfer with plane change is addressed. The complete mission has required three characteristic velocities, a deorbit impulse at high earth orbit (HEO), a boost impulse at the atmospheric exit, and a reorbit impulse at low earth orbit (LEO). A performance index has been formulated as the sum of these three impulses. Application of optimal control principles has led to a nonlinear, two-point, boundary value problem which was solved by using a multiple shooting algorithm. The strategy for the atmospheric portion of the minimum-fuel transfer is to start initially with the maximum positive lift in order to recover from the downward plunge, and then to fly with a gradually decreasing lift such that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  10. Fuel-optimal trajectories of aeroassisted orbital transfer with plane change

    NASA Technical Reports Server (NTRS)

    Naidu, Desineni Subbaramaiah; Hibey, Joseph L.

    1989-01-01

    The problem of minimization of fuel consumption during the atmospheric portion of an aeroassisted, orbital transfer with plane change is addressed. The complete mission has required three characteristic velocities, a deorbit impulse at high earth orbit (HEO), a boost impulse at the atmospheric exit, and a reorbit impulse at low earth orbit (LEO). A performance index has been formulated as the sum of these three impulses. Application of optimal control principles has led to a nonlinear, two-point, boundary value problem which was solved by using a multiple shooting algorithm. The strategy for the atmospheric portion of the minimum-fuel transfer is to start initially with the maximum positive lift in order to recover from the downward plunge, and then to fly with a gradually decreasing lift such that the vehicle skips out of the atmosphere with a flight path angle near zero degrees.

  11. Basic governing equations for the flight regimes of aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Lee, J.-H.

    1984-01-01

    The basic governing equations for the low-density, high-enthalpy flow regimes expected in the shock layers over the heat shields of the proposed aeroassisted orbital transfer vehicles are derived by combining and extending existing theories. The conservation equations are derived from gas kinetic principles for a four-component ionized gas consisting of neutral molecules, neutral atoms, singly ionized ions, and electrons, assuming a continuum flow. The differences among translational-rotational, vibrational, and electron temperatures are accounted for, as well as chemical nonequilibrium and electric-charge separation. Expressions for convective and viscous fluxes, transport properties, and the terms representing interactions among various energy modes are given explicitly. The expressions for the rate of electron-vibration energy transfer, which violates the Landau-Teller conditions, is derived by solving the system of master equations accounting for the multiple-level transitions.

  12. Aeroassist Technology Planning for Exploration

    NASA Technical Reports Server (NTRS)

    Munk, Michelle M.; Powell, Richard W.

    2000-01-01

    Now that the International Space Station is undergoing assembly, NASA is strategizing about the next logical exploration strategy for robotic missions and the next destination for humans. NASA's current efforts are in developing technologies that will both aid the robotic exploration strategy and make human flight to other celestial bodies both safe and affordable. One of these enabling technologies for future robotic and human exploration missions is aeroassist. This paper will (1) define aeroassist, (2) explain the benefits and uses of aeroassist, and (3) describe a method, currently used by the NASA Aeroassist Working Group, by which widely geographically distributed teams can assemble, present, use, and archive technology information.

  13. System technology analysis of aeroassisted orbital transfer vehicles - Moderate lift/drag

    NASA Technical Reports Server (NTRS)

    Florence, D. E.; Fischer, G.

    1983-01-01

    The utilization of procedures involving aerodynamic braking and/or aerodynamic maneuvering on return from higher altitude orbits to low-earth orbit makes it possible to realize significant performance benefits. The present study is concerned with a number of mission scenarios for Aeroassisted Orbital Transfer Vehicles (AOTV) and the impact of potential technology advances in the performance enhancement of the class of AOTV's having a hypersonic lift to drag ratio (L/D) of 0.75 to 1.5. It is found that the synergistic combination of a hypersonic L/D of 1.2, an advanced cryopropelled engine, and an LH2 drop tank (1-1/2 stage) leads to a single 65,000 pound shuttle, two-man geosynchronous mission with 2100 pounds of useful paylod. Additional payload enhancement is possible with AOTV dry weight reductions due to technology advances in the areas of vehicle structures and thermal protection systems and other subsystems.

  14. Problems of rate chemistry in the flight regimes of aeroassisted orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Park, C.

    1984-01-01

    The dissociating and ionizing nonequilibrium flows behind a normal shock wave are calculated for the density and vehicle regimes appropriate for aeroassisted orbital transfer vehicles; the departure of vibrational and electron temperatures from the gas temperature as well as viscous transport phenomena are accounted for. From the thermodynamic properties so determined, radiative power emission is calculated using an existing code. The resulting radiation characteristics are compared with the available experimental data. Chemical parameters are varied to investigate their effect on the radiation characteristics. It is concluded that the current knowledge of rate chemistry leads to a factor-of-4 uncertainty in nonequilibrium radiation intensities. The chemical parameters that must be studied to improve the accuracy are identified.

  15. Problems of Rate Chemistry in the Flight Regimes of Aeroassisted Orbital Transfer Vehicles

    NASA Technical Reports Server (NTRS)

    Park, Chul

    1985-01-01

    The dissociating and ionizing nonequilibrium flows behind a normal shock wave are calculated for the density and vehicle regimes appropriate for aeroassisted orbital transfer vehicles; the departure of vibrational and electron temperatures from the gas temperature as well as viscous transport phenomena are accounted for. From the thermodynamic properties so determined, radiative power emission is calculated using an existing code. The resulting radiation characteristics are compared with the available experimental data. Chemical parameters are varied to Investigate their effect on the radiation characteristics. It is concluded that the current knowledge of rate chemistry leads to a factor-of-4 uncertainty In nonequilibrium radiation intensities. The chemical parameters that must be studied to Improve the accuracy are identified.

  16. Guidance law development for aeroassisted transfer vehicles using matched asymptotic expansions

    NASA Technical Reports Server (NTRS)

    Calise, Anthony J.; Melamed, Nahum

    1993-01-01

    This report addresses and clarifies a number of issues related to the Matched Asymptotic Expansion (MAE) analysis of skip trajectories, or any class of problems that give rise to inner layers that are not associated directly with satisfying boundary conditions. The procedure for matching inner and outer solutions, and using the composite solution to satisfy boundary conditions is developed and rigorously followed to obtain a set of algebraic equations for the problem of inclination change with minimum energy loss. A detailed evaluation of the zeroth order guidance algorithm for aeroassisted orbit transfer is performed. It is shown that by exploiting the structure of the MAE solution procedure, the original problem, which requires the solution of a set of 20 implicit algebraic equations, can be reduced to a problem of 6 implicit equations in 6 unknowns. A solution that is near optimal, requires a minimum of computation, and thus can be implemented in real time and on-board the vehicle, has been obtained. Guidance law implementation entails treating the current state as a new initial state and repetitively solving the zeroth order MAE problem to obtain the feedback controls. Finally, a general procedure is developed for constructing a MAE solution up to first order, of the Hamilton-Jacobi-Bellman equation based on the method of characteristics. The development is valid for a class of perturbation problems whose solution exhibits two-time-scale behavior. A regular expansion for problems of this type is shown to be inappropriate since it is not valid over a narrow range of the independent variable. That is, it is not uniformly valid. Of particular interest here is the manner in which matching and boundary conditions are enforced when the expansion is carried out to first order. Two cases are distinguished-one where the left boundary condition coincides with, or lies to the right of, the singular region, and another one where the left boundary condition lies to the left

  17. Guidance law development for aeroassisted transfer vehicles using Matched Asymptotic Expansions

    NASA Astrophysics Data System (ADS)

    Melamed, Nahum

    This thesis addresses and clarifies a number of issues related to the Matched Asymptotic Expansion (MAE) analysis of skip trajectories, or any class of problems that give rise to inner layers that are not associated directly with satisfying boundary conditions. The procedure for matching inner and outer solutions, and using the composite solution to satisfy boundary conditions is developed and rigorously followed to obtain a set of algebraic equations for the problem of inclination change with minimum energy loss. A detailed evaluation of the zeroth order guidance algorithm for aeroassisted orbit transfer is performed. It is shown that by exploiting the structure of the MAE solution procedure, the original problem, which requires the solution of a set of 20 implicit algebraic equations, can be reduced to a problem of 6 implicit equations in 6 unknowns. A solution that is near optimal, requires a minimum of computation, and thus can be implemented in real time and on-board the vehicle, has been obtained. Guidance law implementation entails treating the current state as a new initial state and repetitively solving the zeroth order MAE problem to obtain the feedback controls. Finally, a general procedure is developed for constructing a MAE solution up to first order, of the Hamilton-Jacobi-Bellman equation based on the method of characteristics. The development is valid for a class of perturbation problems whose solution exhibits two-time-scale behavior. A regular expansion for problems of this type is shown to be inappropriate since it is not valid over a narrow range of the independent variable. That is, it is not uniformly valid. Of particular interest here is the manner in which matching and boundary conditions are enforced when the expansion is carried out to first order. Two cases are distinguished--one where the left boundary condition coincides with, or lies to the right of, the singular region, and another one where the left boundary condition lies to the

  18. Aeroassisted manned transfer vehicle (TAXI) for advanced Mars Transportation: NASA/USRA 1987 Senior Design Project

    NASA Technical Reports Server (NTRS)

    1987-01-01

    A conceptual design study of an aeroassisted orbital transfer vehicle is discussed. Nicknamed TAXI, it will ferry personnel and cargo: (1) between low Earth orbit and a spacecraft circling around the Sun in permanent orbit intersecting gravitational fields of Earth and Mars, and (2) between the cycling spacecraft and a Mars orbiting station, co-orbiting with Phobos. Crew safety and mission flexibility (in terms of ability to provide a wide range of delta-V) were given high priority. Three versions were considered, using the same overall configuration based on a low L/D aerobrake with the geometry of a raked off elliptical cone with ellipsoidal nose and a toroidal skirt. The propulsion system consists of three gimballed LOX/LH2 engines firing away from the aerobrake. The versions differ mainly in the size of the aeroshields and propellant tanks. TAXI A version resulted from an initial effort to design a single transfer vehicle able to meet all delta-V requirements during the 15-year period (2025 to 2040) of Mars mission operations. TAXI B is designed to function with the cycling spacecraft moving in a simplified, nominal trajectory. On Mars missions, TAXI B would be able to meet the requirements of all the missions with a relative approach velocity near Mars of less than 9.3 km/sec. Finally, TAXI C is a revision of TAXI A, a transfer vehicle designed for missions with a relative velocity near Mars larger than 9.3 km/sec. All versions carry a crew of 9 (11 with modifications) and a cargo of 10000 lbm. Trip duration varies from 1 day for transfer from LEO to the cycling ship to nearly 5 days for transfer from the ship to the Phobos orbit.

  19. System technology analysis of aeroassisted orbital transfer vehicles. Moderate lift/drag (0.75-1.5): Volume 1A, part 2: Executive summary, phase 2

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Significant achievements and activities of Phase 2 of a study to assess aeroassisted orbit transfer vehicle (AOTV) system technology are summarized. Phase 2 was directed towards identification and prioritization of technology payoffs of representative space based mid lift/drag ratio (L/D) AOTV's and the cryofueled propulsion subsystem - configuration interactions. Enhancing technology areas were identified which could provide substantial transport cost reduction. These include: (1) improved lifetime of storable propellant engines; (2) avionics weight reduction; (3) external thermal protection system weight reduction; (4) decrease of uncertainties in aerodynamic and aerothermodynamic performance; electrical power subsystem weight reduction due to incorporation of advanced materials; and (6) structural shell weight reduction. Results indicated that advanced aerothermodynamic methodology and aft end configuring may provide an enlarged allowable zone for engine nozzle protrusions into the separated flow region. Payload manifesting and non-hydrogen propellant manifesting at the space station is recommended.

  20. System technology analysis of aeroassisted orbital transfer vehicles: Moderate lift/drag (0.75-1.5). Volume 3: Cost estimates and work breakdown structure/dictionary, phase 1 and 2

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Technology payoffs of representative ground based (Phase 1) and space based (Phase 2) mid lift/drag ratio aeroassisted orbit transfer vehicles (AOTV) were assessed and prioritized. A narrative summary of the cost estimates and work breakdown structure/dictionary for both study phases is presented. Costs were estimated using the Grumman Space Programs Algorithm for Cost Estimating (SPACE) computer program and results are given for four AOTV configurations. The work breakdown structure follows the standard of the joint government/industry Space Systems Cost Analysis Group (SSCAG). A table is provided which shows cost estimates for each work breakdown structure element.

  1. Stagnation-point heat-transfer rate predictions at aeroassist flight conditions

    NASA Technical Reports Server (NTRS)

    Gupta, Roop N.; Jones, Jim J.; Rochelle, William C.

    1992-01-01

    The results are presented for the stagnation-point heat-transfer rates used in the design process of the Aeroassist Flight Experiment (AFE) vehicle over its entire aeropass trajectory. The prediction methods used in this investigation demonstrate the application of computational fluid dynamics (CFD) techniques to a wide range of flight conditions and their usefulness in a design process. The heating rates were computed by a viscous-shock-layer (VSL) code at the lower altitudes and by a Navier-Stokes (N-S) code for the higher altitude cases. For both methods, finite-rate chemically reacting gas was considered, and a temperature-dependent wall-catalysis model was used. The wall temperature for each case was assumed to be radiative equilibrium temperature, based on total heating. The radiative heating was estimated by using a correlation equation. Wall slip was included in the N-S calculation method, and this method implicitly accounts for shock slip. The N-S/VSL combination of projection methods was established by comparison with the published benchmark flow-field code LAURA results at lower altitudes, and the direct simulation Monte Carlo results at higher altitude cases. To obtain the design heating rate over the entire forward face of the vehicle, a boundary-layer method (BLIMP code) that employs reacting chemistry and surface catalysis was used. The ratio of the VSL or N-S method prediction to that obtained from the boundary-layer method code at the stagnation point is used to define an adjustment factor, which accounts for the errors involved in using the boundary-layer method.

  2. Atmospheric guidance concepts for an aeroassist flight experiment

    NASA Technical Reports Server (NTRS)

    Gamble, J. D.; Cerimele, C. J.; Moore, T. E.; Higgins, J.

    1988-01-01

    Three atmospheric guidance concepts proposed for an aeroassist flight experiment are presented. The flight experiment will simulate a return from geosynchronous orbit by an aeroassisted orbital transfer vehicle and is proposed to be flown on board the Space Shuttle in 1992. The three guidance concepts include an analytic predictor/corrector, a numeric predictor/corrector, and an energy controller. The algorithms for the three guidance methods are developed and performance results are presented for the nominal case and for several cases dispersed from the nominal conditions.

  3. Optimal trajectories for the aeroassisted flight experiment

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Lee, W. Y.; Zhao, Z. G.

    1989-01-01

    The determination of optimal trajectories for the aeroassisted flight experiment (AFE) is discussed. The intent of this experiment is to simulate a GEO-to-LEO transfer, where GEO denotes a geosynchronous earth orbit and LEO denotes a low earth orbit. The trajectories of an AFE spacecraft are analyzed in a 3D-space, employing the full system of 6 ordinary differential equations (ODEs) describing the atmospheric pass. The atmospheric entry conditions are given, and the atmospheric exit conditions are adjusted. Two possible transfers are considered: (1) indirect ascent to a 178 NM perigee via a 197 NM apogee; and (2) direct ascent to a 178 NM apogee.

  4. Moderate lift-to-drag aeroassist

    NASA Technical Reports Server (NTRS)

    Florence, D. E.; Fischer, G.

    1984-01-01

    Significant performance benefits are realized via aerodynamic braking and/or aerodynamic maneuvering on return from higher altitude orbits to low Earth orbit. This approach substantially reduces the mission propellant requirements by using the aerodynamic drag, D, to brake the vehicle to near circular velocity and the aerodynamic lift, L, to null out accumulated errors as well as change the orbital inclination to that required for rendezvous with the Space Shuttle Orbiter. Broad concept evaluations were performed and the technology requirements and sensitivities for aeroassisted OTV's over a range of vehicle hypersonic L/D from 0.75 to 1.5 were systematically identified and assessed. The aeroassisted OTV is capable of evolving from an initial delivery only system to one eventually capable of supporting manned roundtrip missions to geosynchronous orbit. Concept screening was conducted on numerous configurations spanning the L/D = 0.75 to 1.5 range, and several with attractive features were identified. Initial payload capability was evaluated for a baseline of delivery to GEO, six hour polar, and Molniya (12 hours x 63.4 deg) orbits with return and recovery of the aeroassist orbit transfer vehicle (AOTV) at LEO. Evolutionary payload requirements that were assessed include a GEO servicing mission (6K up and 2K return) and a manned GEO mission (14K roundtrip).

  5. System technology analysis of aeroassisted orbital transfer vehicles: Moderate lift/drag (0.75-1.5),volume 1B, part 1, study results

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Significant performance benefits can be realized via aerodynamic breaking and/or aerodynamic maneuvering on return from higher altitude orbits to low Earth orbit. This approach substantially reduces the mission propellant requirements by using the aerodynamic drag, D, to brake the vehicle to near circular velocity and the aerodynamic lift, L, to null out accumulated errors as well as change the orbital inclination to that required for rendezous with the Space Shuttle Orbiter. A study was completed where broad concept evaluations were performed and the technology requirements and sensitivities for aeroassisted Orbital Transfer Vehicles (AOTVs) over a range of vehicle hypersonic L/D from 0.75 to 1.5 were systematically identified and assessed. The AOTV is capable of evolving from an initial delivery only system to one eventually capable of supporting manned roundtrip missions to geosynchronous orbit. Concept screenings were conducted on numerous configurations spanning the L/D = 0.75 to 1.5 range, and several with attractive features were identified. Initial payload capability was evaluated for a baseline of delivery to GEO, six hour polar, and Molniya orbits with return and recovery of the AOTV at LEO. Evolutionary payload requirements that were assessed include a GEO servicing mission and a manned GEO mission.

  6. Aeroassist flight experiment aerodynamics and aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Brewer, Edwin B.

    1989-01-01

    The problem is to determine the transitional flow aerodynamics and aerothermodynamics, including the base flow characteristics, of the Aeroassist Flight Experiment (AFE). The justification for the computational fluid dynamic (CFD) Application stems from MSFC's system integration responsibility for the AFE. To insure that the AFE objectives are met, MSFC must understand the limitations and uncertainties of the design data. Perhaps the only method capable of handling the complex physics of the rarefied high energy AFE trajectory is Bird's Direct Simulation Monte Carlo (DSMC) technique. The 3-D code used in this analysis is applicable only to the AFE geometry. It uses the Variable Hard Sphere (VHS) collision model and five specie chemistry model available from Langley Research Center. The code is benchmarked against the AFE flight data and used as an Aeroassisted Space Transfer Vehicle (ASTV) design tool. The code is being used to understand the AFE flow field and verify or modify existing design data. Continued application to lower altitudes is testing the capability of the Numerical Aerodynamic Simulation Facility (NASF) to handle 3-D DSMC and its practicality as an ASTV/AFE design tool.

  7. Optimal trajectories for the aeroassisted flight experiment

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Lee, W. Y.; Zhao, Z. G.

    1989-01-01

    The optimal trajectories of the aeroassisted flight experiment (AFE) spacecraft are analyzed in a three-dimensional space using the full system of six ODEs describing the atmospheric pass. The optimal trajectories are computed for two possible transfers: indirect ascent to a 178 NM perigee via a 197 NM apogee and direct ascent to a 178 NM apogee. For each transfer, two cases are investigated: (1) the bank angle is continuously variable, and (2) the trajectory is divided into segments along which the bank angle is constant. It is shown that the optimal trajectories for both cases coalesce into a two subarc trajectory, with the bank angle constant in each subarc. It is also shown that, during the atmospheric pass, the peak values of the changes of the orbital inclination and the longitude of the ascending node are nearly zero.

  8. Optimal aeroassisted return from high earth orbit with plane change

    NASA Astrophysics Data System (ADS)

    Vinh, Nguyen X.; Hanson, John M.

    This paper gives a complete analysis of the problem of aeroassisted return from a high Earth orbit to a low Earth orbit with plane change. A discussion of pure propulsive maneuver leads to the necessary change for improvement of the fuel consumption by inserting in the middle of the trajectory an atmospheric phase to obtain all or part of the required plane change. The variational problem is reduced to a parametric optimization problem by using the known results in optimal impulsive transfer and solving the atmospheric turning problem for storage and use in the optimization process. The coupling effect between space maneuver and atmospheric maneuver is discussed. Depending on the values of the plane change i, the ratios of the radii, n = r 1/r 2 between the orbits and a = r 2/R between the low orbit and the atmosphere, and the maximum lift-to-drag ratio E∗ of the vehicle, the optimal maneuver can be pure propulsive or aeroassisted. For aeroassisted maneuver, the optimal mode can be parabolic, which requires only drag capability of the vehicle, or elliptic. In the elliptic mode, it can be by one-impulse for deorbit and one or two-impulse in postatmospheric flight, or by two-impulse for deorbit with only one impulse for final circularization. It is shown that whenever an impulse is applied, a plane change is made. The necessary conditions for the optimal split of the plane changes are derived and mechanized in a program routine for obtaining the solution.

  9. Multipass aeroassisted transfer between coplanar elliptical orbits in the presence of atmospheric density variations

    NASA Astrophysics Data System (ADS)

    Gur, Ilana; Taratuta, Aba; Mishne, David

    Planar rotation of the line of apsides of a lifting space vehicle in elliptical orbit, using three thrust impulses and several consecutive atmospheric passes is discussed. During the atmospheric pass, a lift force is applied in order to rotate the line of apsides of the orbit. Variations in the atmospheric density, and the dependence of the aerodynamic coefficients on the altitude were taken into account. It was found that letting the spacecraft undergo consecutive passes through the atmosphere, and compensating for the velocity loss after the final angle of rotation is achieved, is more fuel economic than compensating the velocity loss after every atmospheric pass. It was also found that variations in atmospheric density do not affect the overall fuel consumption per unit angle of rotation, though it has an influence on the amount of rotation in a single pass. The dependence of aerodynamic coefficients on the altitude has minor influence on the fuel consumption.

  10. GLOBAL REFERENCE ATMOSPHERIC MODELS FOR AEROASSIST APPLICATIONS

    NASA Technical Reports Server (NTRS)

    Duvall, Aleta; Justus, C. G.; Keller, Vernon W.

    2005-01-01

    Aeroassist is a broad category of advanced transportation technology encompassing aerocapture, aerobraking, aeroentry, precision landing, hazard detection and avoidance, and aerogravity assist. The eight destinations in the Solar System with sufficient atmosphere to enable aeroassist technology are Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Saturn's moon Titan. Engineering-level atmospheric models for five of these targets - Earth, Mars, Titan, Neptune, and Venus - have been developed at NASA's Marshall Space Flight Center. These models are useful as tools in mission planning and systems analysis studies associated with aeroassist applications. The series of models is collectively named the Global Reference Atmospheric Model or GRAM series. An important capability of all the models in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analysis in developing guidance, navigation and control algorithms, for aerothermal design, and for other applications sensitive to atmospheric variability. Recent example applications are discussed.

  11. Project ARGO: The design and analysis of an all-propulsive and an aeroassisted version of a manned space transportation vehicle

    NASA Technical Reports Server (NTRS)

    Wang, H.; Seifert, D.; Waidelich, J.; Mileski, M.; Herr, D.; Wilks, M.; Law, G.; Folz, A.

    1989-01-01

    The Senior Aerospace System Design class at the University of Michigan undertook the design of a manned space transportation vehicle (STV) that would transport payloads between low earth orbit (LEO) and geosynchronous earth orbit (GEO). Designated ARGO after the ship of the Greek adventurer Jason, two different versions of an STV that would be based, refueled, and serviced at the Space Station Freedom were designed and analyzed by the class. With the same 2-man/7-day nominal mission of transporting a 10,000-kg payload up to GEO and bringing a 5000-kg payload back to LEO, the two versions of ARGO differ in the manner in which the delta V is applied to insert the vehicle into LEO upon return from GEO. The all-propulsive ARGO (or CSTV for chemical STV) uses thrust from its LH2/LOX rocket engines to produce the delta V during all phases of its mission. While the aeroassisted ARGO (or ASTV for aeroassisted STV) also uses the same engines for the majority of the mission, the final delta V used to insert the ASTV into LEO is produced by skimming the Earth's atmosphere and using the drag on the vehicle to apply the required delta V. This procedure allows for large propellant, and thus cost, savings, but creates many design problems such as the high heating rates and decelerations experienced by a vehicle moving through the atmosphere at hypersonic velocities. The design class, consisting of 43 senior aerospace engineering students, was divided into one managerial and eight technical groups. The technical groups consisted of spacecraft configuration and integration, mission analysis, atmospheric flight, propulsion, power and communications, life support and human factors, logistics and support, and systems analysis. Two committees were set up with members from each group to create the scale models of the STV's and to produce the final report.

  12. Project Argo: The design and analysis of an all-propulsive and an aeroassisted version of a manned space transportation vehicle

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Project Argo is the design of a manned Space Transportation Vehicle (STV) that would transport payloads between LEO (altitude lying between 278 to 500 km above the Earth) and GEO (altitude is approximately 35,800 km above the Earth) and would be refueled and refurbished at the Space Station Freedom. Argo would be man's first space-based manned vehicle and would provide a crucial link to geosynchronous orbit where the vast majority of satellites are located. The vehicle could be built and launched shortly after the space station and give invaluable space experience while serving as a workhorse to deliver and repair satellites. Eventually, if a manned space station is established in GEO, then Argo could serve as the transport between the Space Station Freedom and a Geostation. If necessary, modifications could be made to allow the vehicle to reach the moon or possibly Mars. Project Argo is unique in that it consists of the design and comparison of two different concepts to accomplish the same mission. The first is an all-propulsive vehicle which uses chemical propulsion for all of its major maneuvers between LEO and GEO. The second is a vehicle that uses aeroassisted braking during its return from GEO to LEO by passing through the upper portions of the atmosphere.

  13. Wind-tunnel based definition of the AFE aerothermodynamic environment. [Aeroassist Flight Experiment

    NASA Technical Reports Server (NTRS)

    Miller, Charles G.; Wells, W. L.

    1992-01-01

    The Aeroassist Flight Experiment (AFE), scheduled to be performed in 1994, will serve as a precursor for aeroassisted space transfer vehicles (ASTV's) and is representative of entry concepts being considered for missions to Mars. Rationale for the AFE is reviewed briefly as are the various experiments carried aboard the vehicle. The approach used to determine hypersonic aerodynamic and aerothermodynamic characteristics over a wide range of simulation parameters in ground-based facilities is presented. Facilities, instrumentation and test procedures employed in the establishment of the data base are discussed. Measurements illustrating the effects of hypersonic simulation parameters, particularly normal-shock density ratio (an important parameter for hypersonic blunt bodies), and attitude on aerodynamic and aerothermodynamic characteristics are presented, and predictions from computational fluid dynamic (CFD) computer codes are compared with measurement.

  14. System technology analysis of aeroassisted orbital transfer vehicles. Moderate lift/drag (0.75-1.5). Volume 1A, part 1: Executive summary, phase 1

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Activities and significant results of Phase 1 of a study to access aeroassisted orbit transfer vehicle (AOTV) system technology are summarized. Broad concept evaluations were performed and the technology requirements and sensitivities for ground based AOTV's over a range of vehicle hypersonic lift/drag (L/D) from 0.75 to 1.5 were systematically identified and assessed. The four major task areas included systems analysis, system/subsystem trades, technology payoff assessment and plan, and cost analysis. Findings indicate that substantial performance improvements and hence cost benefit can be obtained by developing enhanced technologies such as: (1) low thrust advanced expander LOX-hydrogen engines with specific impulse of 480 to 490 sec; (2) reducing the external thermal protection system weight and increasing the maximum allowable bond/structure temperature; and (3) reducing the structural shell weight by improving the quality of the design allowable data, or use of advanced structural materials. Results also show that use of mid L/D AOTV's provide significant aerodynamic plane change capability and control authority over trajectory dispersions and off-nominal atmospheres.

  15. Aeroassist flight experiment guidance, navigation and control

    NASA Technical Reports Server (NTRS)

    Brand, Timothy J.; Engel, Albert G.

    1986-01-01

    The Aeroassist Flight Experiment scheduled for the early 1990's will demonstrate the use of a low L/D lifting brake using aerodynamic drag to return a spacecraft from a high energy to a low earth orbit. The experimental vehicle will be deployed and retrieved by the Shuttle Orbiter. This paper reviews some of the challenges, problems, and solutions encountered to date during guidance system development, with emphasis on technology advances which will benefit an operational Orbit Transfer Vehicle (OTV). Key factors to be discussed include guidance alternatives, aerodynamic modeling, navigation requirements, the impact of atmospheric uncertainties, and flight profile alternatives considered during initial planning.

  16. Aero-Assisted Spacecraft Missions Using Hypersonic Waverider Aeroshells

    NASA Astrophysics Data System (ADS)

    Knittel, Jeremy

    This work examines the use of high-lift, low drag vehicles which perform orbital transfers within a planet's atmosphere to reduce propulsive requirements. For the foreseeable future, spacecraft mission design will include the objective of limiting the mass of fuel required. One means of accomplishing this is using aerodynamics as a supplemental force, with what is termed an aero-assist maneuver. Further, the use of a lifting body enables a mission designer to explore candidate trajectory types wholly unavailable to non-lifting analogs. Examples include missions to outer planets by way of an aero-gravity assist, aero-assisted plane change, aero-capture, and steady atmospheric periapsis probing missions. Engineering level models are created in order to simulate both atmospheric and extra-atmospheric space flight. Each mission is parameterized using discrete variables which control multiple areas of design. This work combines the areas of hypersonic aerodynamics, re-entry aerothermodynamics, spacecraft orbital mechanics, and vehicle shape optimization. In particular, emphasis is given to the parametric design of vehicles known as "waveriders" which are inversely designed from known shock flowfields. An entirely novel means of generating a class of waveriders known as "starbodies" is presented. A complete analysis is performed of asymmetric starbody forms and compared to a better understood parameterization, "osculating cone" waveriders. This analysis includes characterization of stability behavior, a critical discipline within hypersonic flight. It is shown that asymmetric starbodies have significant stability improvement with only a 10% reduction in the lift-to-drag ratio. By combining the optimization of both the shape of the vehicle and the trajectory it flies, much is learned about the benefit that can be expected from lifting aero-assist missions. While previous studies have conceptually proven the viability, this work provides thorough quantification of the

  17. Conservation equations and physical models for hypersonic air flows over the aeroassist flight experiment vehicle

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    1989-01-01

    The code development and application program for the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA), with emphasis directed toward support of the Aeroassist Flight Experiment (AFE) in the near term and Aeroassisted Space Transfer Vehicle (ASTV) design in the long term is reviewed. LAURA is an upwind-biased, point-implicit relaxation algorithm for obtaining the numerical solution to the governing equations for 3-D, viscous, hypersonic flows in chemical and thermal nonequilibrium. The algorithm is derived using a finite volume formulation in which the inviscid components of flux across cell walls are described with Roe's averaging and Harten's entropy fix with second-order corrections based on Yee's Symmetric Total Variation Diminishing scheme. Because of the point-implicit relaxation strategy, the algorithm remains stable at large Courant numbers without the necessity of solving large, block tri-diagonal systems. A single relaxation step depends only on information from nearest neighbors. Predictions for pressure distributions, surface heating, and aerodynamic coefficients compare well with experimental data for Mach 10 flow over an AFE wind tunnel model. Predictions for the hypersonic flow of air in chemical and thermal nonequilibrium over the full scale AFE configuration obtained on a multi-domain grid are discussed.

  18. Optimal trajectories for the Aeroassisted Flight Experiment. Part 2: Equations of motion in an inertial system

    NASA Technical Reports Server (NTRS)

    Miele, A.; Zhao, Z. G.; Lee, W. Y.

    1989-01-01

    The determination of optimal trajectories for the aeroassisted flight experiment (AFE) is discussed. The AFE refers to the study of the free flight of an autonomous spacecraft, shuttle-launched and shuttle-recovered. Its purpose is to gather atmospheric entry environmental data for use in designing aeroassisted orbital transfer vehicles (AOTV). It is assumed that: (1) the spacecraft is a particle of constant mass; (2) the Earth is rotating with constant angular velocity; (3) the Earth is an oblate planet, and the gravitational potential depends on both the radial distance and the latitude (harmonics of order higher than four are ignored); and (4) the atmosphere is at rest with respect to the Earth. Under these assumptions, the equations of motion for hypervelocity atmospheric flight (which can be used not only for AFE problems, but also for AOT problems and space shuttle problems) are derived in an inertial system. Transformation relations are supplied which allow one to pass from quantities computed in an inertial system to quantities computed in an Earth-fixed system and vice versa.

  19. Optimal trajectories for the aeroassisted flight experiment. Part 3: Formulation, results, and analysis

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Lee, W. Y.; Zhao, Z. G.

    1989-01-01

    The determination of optimal trajectories for the aero-assisted flight experiment (AFE) is investigated. The intent of this experiment is to simulate a GEO-to-LEO transfer, where GEO denotes a geosynchronous Earth orbit and LEO denotes a low Earth orbit. The trajectories of an AFE spacecraft are analyzed in a 3D-space, employing the full system of 6 ODEs describing the atmospheric pass. The atmospheric entry conditions are given, and the atmospheric exit conditions are adjusted in such a way that the following conditions are satisfied: (1) the atmospheric velocity depletion is such that, after exiting, the AFE spacecraft first ascends to a specified apogee and then descends to a specified perigee; and (2) the exit orbital plane is identical with the entry orbital plane. The final maneuver, not analyzed here, includes the rendezvous with and the capture by the space shuttle.

  20. Dual Space Technology Transfer

    NASA Astrophysics Data System (ADS)

    Kowbel, W.; Loutfy, R.

    2009-03-01

    Over the past fifteen years, MER has had several NASA SBIR Phase II programs in the area of space technology, based upon carbon-carbon (C-C) composites. In addition, in November 2004, leading edges supplied by MER provided the enabling technology to reach a Mach 10 record for an air breathing engine on the X-43 A flight. The MER business model constitutes a spin-off of technologies initially by incubating in house, and ultimately creating spin-off stand alone companies. FMC was formed to provide for technology transfer in the area of fabrication of C-C composites. FMC has acquired ISO 9000 and AS9100 quality certifications. FMC is fabricating under AS9100 certification, flight parts for several flight programs. In addition, FMC is expanding the application of carbon-carbon composites to several critical military programs. In addition to space technology transfer to critical military programs, FMC is becoming the world leader in the commercial area of low-cost C-C composites for furnace fixtures. Market penetrations have been accomplished in North America, Europe and Asia. Low-cost, quick turn-around and excellent quality of FMC products paves the way to greatly increased sales. In addition, FMC is actively pursuing a joint venture with a new partner, near closure, to become the leading supplier of high temperature carbon based composites. In addition, several other spin-off companies such as TMC, FiC, Li-Tech and NMIC were formed by MER with a plethora of potential space applications.

  1. Computational Aerothermodynamics in Aeroassist Applications

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    2001-01-01

    Aeroassisted planetary entry uses atmospheric drag to decelerate spacecraft from super-orbital to orbital or suborbital velocities. Numerical simulation of flow fields surrounding these spacecraft during hypersonic atmospheric entry is required to define aerothermal loads. The severe compression in the shock layer in front of the vehicle and subsequent, rapid expansion into the wake are characterized by high temperature, thermo-chemical nonequilibrium processes. Implicit algorithms required for efficient, stable computation of the governing equations involving disparate time scales of convection, diffusion, chemical reactions, and thermal relaxation are discussed. Robust point-implicit strategies are utilized in the initialization phase; less robust but more efficient line-implicit strategies are applied in the endgame. Applications to ballutes (balloon-like decelerators) in the atmospheres of Venus, Mars, Titan, Saturn, and Neptune and a Mars Sample Return Orbiter (MSRO) are featured. Examples are discussed where time-accurate simulation is required to achieve a steady-state solution.

  2. Optimal trajectories for the Aeroassisted Flight Experiment. Part 1: Equations of motion in an Earth-fixed system

    NASA Technical Reports Server (NTRS)

    Miele, A.; Zhao, Z. G.; Lee, W. Y.

    1989-01-01

    The determination of optimal trajectories for the aeroassisted flight experiment (AFE) is discussed. The AFE refers to the study of the free flight of an autonomous spacecraft, shuttle-launched and shuttle-recovered. Its purpose is to gather atmospheric entry environmental data for use in designing aeroassisted orbital transfer vehicles (AOTV). It is assumed that: (1) the spacecraft is a particle of constant mass; (2) the Earth is rotating with constant angular velocity; (3) the Earth is an oblate planet, and the gravitational potential depends on both the radial distance and the latitude (harmonics of order higher than four are ignored); and (4) the atmosphere is at rest with respect to the Earth. Under these assumptions, the equations of motion for hypervelocity atmospheric flight (which can be used not only for AFE problems, but also for AOT problems and space shuttle problems) are derived in an Earth-fixed system. Transformation relations are supplied which allow one to pass from quantities computed in an Earth-fixed system to quantities computed in an inertial system, and vice versa.

  3. Decomposition technique and optimal trajectories for the aeroassisted flight experiment

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Deaton, A. W.

    1990-01-01

    An actual geosynchronous Earth orbit-to-low Earth orbit (GEO-to-LEO) transfer is considered with reference to the aeroassisted flight experiment (AFE) spacecraft, and optimal trajectories are determined by minimizing the total characteristic velocity. The optimization is performed with respect to the time history of the controls (angle of attack and angle of bank), the entry path inclination and the flight time being free. Two transfer maneuvers are considered: direct ascent (DA) to LEO and indirect ascent (IA) to LEO via parking Earth orbit (PEO). By taking into account certain assumptions, the complete system can be decoupled into two subsystems: one describing the longitudinal motion and one describing the lateral motion. The angle of attack history, the entry path inclination, and the flight time are determined via the longitudinal motion subsystem. In this subsystem, the difference between the instantaneous bank angle and a constant bank angle is minimized in the least square sense subject to the specified orbital inclination requirement. Both the angles of attack and the angle of bank are shown to be constant. This result has considerable importance in the design of nominal trajectories to be used in the guidance of AFE and aeroassisted orbital transfer (AOT) vehicles.

  4. The aerobraking space transfer vehicle

    NASA Technical Reports Server (NTRS)

    Andrews, Glen; Carpenter, Brian; Corns, Steve; Harris, Robert; Jun, Brian; Munro, Bruce; Pulling, Eric; Sekhon, Amrit; Welton, Walt; Jakubowski, A.

    1990-01-01

    With the advent of the Space Station and the proposed Geosynchronous Operation Support Center (GeoShack) in the early 21st century, the need for a cost effective, reusable orbital transport vehicle has arisen. This transport vehicle will be used in conjunction with the Space Shuttle, the Space Station, and GeoShack. The vehicle will transfer mission crew and payloads between low earth and geosynchronous orbits with minimal cost. Recent technological advances in thermal protection systems such as those employed in the Space Shuttle have made it possible to incorporate and aerobrake on the transfer vehicle to further reduce transport costs. The research and final design configuration of the aerospace senior design team from VPISU, working in conjunction with NASA, are presented. The topic of aerobraking and focuses on the evolution of an Aerobraking Space Transfer Vehicle (ASTV), is addressed.

  5. Space transfer vehicles and space basing

    NASA Technical Reports Server (NTRS)

    Kelley, Joe

    1991-01-01

    The topics covered include the following: (1) space basing agenda; (2) mission scenario 4E-5B, crew and Lunar Excursion Vehicle (LEV) delivery; (3) final concept candidate, crew concept 4E-2B; (4) space transfer vehicle (STV) concept 4E-5B; (5) configuration summary for crew concept 4E-5B; (6) configuration definition for crew concept 4E-5B; (7) low earth orbit node assembly and checkout operations; (8) criteria for operation objectives; (9) LTV and STV main engines; (10) Space Station Freedom impacts; (11) aerobrakes; and (12) on orbit operations. This document is presented in viewgraph form.

  6. Three orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Aerospace engineering students at the Virginia Polytechnic Institute and State University undertook three design projects under the sponsorship of the NASA/USRA Advanced Space Design Program. All three projects addressed cargo and/or crew transportation between low Earth orbit and geosynchronous Earth orbit. Project SPARC presents a preliminary design of a fully reusable, chemically powered aeroassisted vehicle for a transfer of a crew of five and a 6000 to 20000 pound payload. The ASTV project outlines a chemically powered aeroassisted configuration that uses disposable tanks and a relatively small aerobrake to realize propellant savings. The third project, LOCOST, involves a reusable, hybrid laser/chemical vehicle designed for large cargo (up to 88,200 pounds) transportation.

  7. Orbital Transfer Vehicle (space taxi) with aerobraking at Earth and Mars

    NASA Technical Reports Server (NTRS)

    1987-01-01

    This report shall cover all major aspects of the design of an Aeroassisted Manned Transfer Vehicle (or TAXI) for use as part of advanced manned Mars missions based on a cycling ship concept. Along with the heliocentric orbiting Cycling Spacecraft, such a TAXI would be a primary component of a long-term transportation system for Mars exploration. The Aeroassisted Manned Transfer Vehicle (AMTV) design developed shall operate along transfer trajectories between Earth and a Cycling Spacecraft (designed by the University of Michigan) and Mars. All operations of the AMTV shall be done primarily within the sphere of influence of the two planets. Maximum delta-V's for the vehicle have been established near 9 km/sec, with transfer durations of about 3 days. Acceleration deltaV's will be accomplished using 3 SSME-based hydrogen-oxygen chemical rockets (l(sub sp) = 485 sec & Thrust greater than = 300,00 Ib(sub f)/engine) with a thrust vector directly opposite the aerobraking deceleration vector. The aerobraking deceleration portion of an AMTV mission would be accomplished in this design by a moderate L/D aeroshield of an ellipsoidally-blunt, raked-off, elliptic cone (EBROEC) shape. The reusable thermal protection material comprising the shield will consist of a flexible, multi-layer, ceramic fabric stretched over a lightweight, rigid, shape - defining truss structure. Behind this truss, other components, including the engine supports, would be attached and protected from heating during aerobraking passes. Among these other components would be 2 LOX tanks and 4 LH2 tanks (and their support frames) holding over 670,000 lbm of propellant necessary to impart the required delta-V to the 98,000 lbm burnout mass vehicle. A 20,000 lbm crew module with docking port (oriented parallel to the accel./decel. axis) will provide accommodations for 9 crew members (11 under extreme conditions) for durations up to seven days, thus allowing extra time for emergency situations. This AMTV will be

  8. Guidance for an aeroassisted orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Hall, Kenneth R.

    1988-01-01

    The use of atmospheric drag for slowing satellite in high energy, high apogee orbits to a lower energy, lower apogee orbit about the Earth is investigated. The high energy orbit is assumed to intercept the Earth's atmosphere. Guidance for the atmospheric phase of the trajectory may be done using the aerodynamic forces generated by the passage through the atmosphere. This research was concerned with the investigation of several methods of guidance during the atmospheric phase to cause a significant reduction in the final velocity as the vehicle leaves the atmosphere. In addition, the velocity direction was controlled to exit to a desired target orbit. Lastly excess aerodynamic lift was used to effect a plane change between the entry orbit plane and the exit orbit plane to achieve a desired orbit plane. The guidance methods were applied to a 3 degree-of-freedom simulation which included an oblate Earth gravity model and a rotating atmosphere. Simulation results were compared on the basis of speed of computation of the guidance parameters and amount of added velocity necessary to achieve the desired orbit.

  9. Simulation and analyses of the aeroassist flight experiment attitude update method

    NASA Technical Reports Server (NTRS)

    Carpenter, J. R.

    1991-01-01

    A method which will be used to update the alignment of the Aeroassist Flight Experiment's Inertial Measuring Unit is simulated and analyzed. This method, the Star Line Maneuver, uses measurements from the Space Shuttle Orbiter star trackers along with an extended Kalman filter to estimate a correction to the attitude quaternion maintained by an Inertial Measuring Unit in the Orbiter's payload bay. This quaternion is corrupted by on-orbit bending of the Orbiter payload bay with respect to the Orbiter navigation base, which is incorporated into the payload quaternion when it is initialized via a direct transfer of the Orbiter attitude state. The method of updating this quaternion is examined through verification of baseline cases and Monte Carlo analysis using a simplified simulation, The simulation uses nominal state dynamics and measurement models from the Kalman filter as its real world models, and is programmed on Microvax minicomputer using Matlab, and interactive matrix analysis tool. Results are presented which confirm and augment previous performance studies, thereby enhancing confidence in the Star Line Maneuver design methodology.

  10. Aeroassist flight experiment guidance Quiet Time

    NASA Technical Reports Server (NTRS)

    Striepe, Scott A.; Suit, William T.

    1988-01-01

    The science experiments for the Aeroassist Flight Experiment (AFE) will be greatly enhanced by taking measurements with no Reaction Control System (RCS) contamination just before perigee. Methods of modifying the AFE guidance to accomplish this are discussed. Several methods that could give up to 30 seconds of quiet time were investigated and the results of these guidance modifications shown. A 20 second quiet time is definitely possible and a 30 second quiet time may be possible if the guidance can be inactive past perigee. Some of the most significant being the criterion for determining if the mission is threatened. A limited follow-on test program is outlined.

  11. Technology transfer and space science missions

    NASA Technical Reports Server (NTRS)

    Acuna, Mario

    1992-01-01

    Viewgraphs on technology transfer and space science missions are provided. Topics covered include: project scientist role within NASA; role of universities in technology transfer; role of government laboratories in research; and technology issues associated with science.

  12. NASA Tests Transfer Device for Space Station

    NASA Video Gallery

    Inside the Space Vehicle Mockup Facility at Johnson Space Center in Houston, NASA tests the Japanese Experiment Module ORU Transfer Interface, or JOTI. This device would allow astronauts to transfe...

  13. Aero-Assisted Pre-Stage for Ballistic and Aero-Assisted Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Ustinov, Eugene A.

    2012-01-01

    A concept of an aero-assisted pre-stage is proposed, which enables launch of both ballistic and aero-assisted launch vehicles from conventional runways. The pre-stage can be implemented as a delta-wing with a suitable undercarriage, which is mated with the launch vehicle, so that their flight directions are coaligned. The ample wing area of the pre-stage combined with the thrust of the launch vehicle ensure prompt roll-out and take-off of the stack at airspeeds typical for a conventional jet airliner. The launch vehicle is separated from the pre-stage as soon as safe altitude is achieved, and the desired ascent trajectory is reached. Nominally, the pre-stage is non-powered. As an option, to save the propellant of the launch vehicle, the pre-stage may have its own short-burn propulsion system, whereas the propulsion system of the launch vehicle is activated at the separation point. A general non-dimensional analysis of performance of the pre-stage from roll-out to separation is carried out and applications to existing ballistic launch vehicle and hypothetical aero-assisted vehicles (spaceplanes) are considered.

  14. Atmospheric Models for Aeroentry and Aeroassist

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Keller, Vernon W.

    2004-01-01

    Eight destinations in the Solar System have sufficient atmosphere for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level atmospheric models for Earth, Mars, Titan, and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications. Development has begun on a similar atmospheric model for Venus. An important capability of these models is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these atmospheric models are compared, and example applications for aerocapture are presented. Recent Titan atmospheric model updates are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars atmospheric model, in support of future Mars aerocapture systems analysis studies, are also presented.

  15. Atmospheric Models for Aeroentry and Aeroassist

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Keller, Vernon W.

    2005-01-01

    Eight destinations in the Solar System have sufficient atmosphere for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level atmospheric models for Earth, Mars, Titan, and Neptune have been developed for use in NASA's systems analysis studies of aerocapture applications. Development has begun on a similar atmospheric model for Venus. An important capability of these models is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these atmospheric models are compared, and example applications for aerocapture are presented. Recent Titan atmospheric model updates are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars atmospheric model, in support of future Mars aerocapture systems analysis studies, are also presented.

  16. Flight stagnation-point heating calculations on Aeroassist Flight Experiment vehicle

    NASA Technical Reports Server (NTRS)

    Hamilton, H. H., II; Gupta, Roop N.; Jones, Jim J.

    1991-01-01

    NASA's Aeroassist Flight Experiment (AFE) vehicle will be deployed from the Space Shuttle Orbiter in 1994 to make a data-gethering aeropass through the upper atmosphere before returning to orbit for Shuttle pickup. An axisymmetric, chemically-reacting viscous shock-layer code is presently used to calculate AFE heating rates which automatically accounts for the viscous-inviscid interaction and entropy layer-swallowing effects which are ignored by the conventional boundary-layer methods. Results are presented for the stagnation-point heating of the current AFE baseline trajectory.

  17. A guidance law for the aeroassisted plane change maneuver in the presence of atmospheric uncertainties

    NASA Technical Reports Server (NTRS)

    Mishne, D.; Speyer, J. L.

    1986-01-01

    A stochastic feedback control law for a space vehicle performing an aeroassisted plane-change maneuver is developed. The stochastic control law is designed to minimize the energy loss while taking into consideration the uncertainty in the atmospheric density. The solution is based on expansion of the stochastic Hamilton-Jacobi-Bellman equation (or dynamic programming) about a zeroth-order known integrable solution. The resulting guidance law is expressed as a series expansion in the noise power spectral densities. A numerical example indicates the potential improvement of this method.

  18. Optimal trajectories for the aeroassisted flight experiment. Part 4: Data, tables, and graphs

    NASA Technical Reports Server (NTRS)

    Miele, A.; Wang, T.; Lee, W. Y.; Wang, H.; Wu, G. D.

    1989-01-01

    The determination of optimal trajectories for the aeroassisted flight experiment (AFE) is discussed. Data, tables, and graphs relative to the following transfers are presented: (IA) indirect ascent to a 178 NM perigee via a 197 NM apogee; and (DA) direct ascent to a 178 NM apogee. For both transfers, two cases are investigated: (1) the bank angle is continuously variable; and (2) the trajectory is divided into segments along which the bank angle is constant. For case (2), the following subcases are studied: two segments, three segments, four segments, and five segments; because the time duration of each segment is optimized, the above subcases involve four, six, eight, and ten parameters, respectively. Presented here are systematic data on a total of ten optimal trajectories (OT), five for Transfer IA and five for Transfer DA. For comparison purposes and only for Transfer IA, a five-segment reference trajectory RT is also considered.

  19. Propulsion issues for advanced orbit transfer vehicles

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.

    1984-01-01

    Studies of the United States Space Transportation System show that in the mid to late 1990s expanded capabilities for orbital transfer vehicles (OTV) will be needed to meet increased payload requirements for transporting materials and possibly men to geosynchronous orbit. Discussion and observations relative to the propulsion system issues of space basing, aeroassist compatibility, man ratability and enhanced payload delivery capability are presented. These issues will require resolution prior to the development of a propulsion system for the advanced OTV. The NASA program in support of advanced propulsion for an OTV is briefly described along with conceptual engine design characteristics.

  20. Technology transfer trends in Indian space programme

    NASA Astrophysics Data System (ADS)

    Sridhara Murthi, K. R.; Shoba, T. S.

    2010-10-01

    Indian space programme, whose objectives involve acceleration of economic and social development through applications of space technology, has been engaged in the development of state-of-the-art satellite systems, launch vehicles and equipment necessary for applications. Even during the early phase of evolution of this Programme, deliberate policies have been adopted by the national space agency, namely, Indian Space Research Organisation (ISRO), to promote spin-off benefit from the technologies developed for the use of space projects. Consistently adhering to this policy, ISRO has transferred over 280 technologies till date, spanning a wide spectrum of disciplines. This has resulted in a fruitful two-way cooperation between a number of SMEs and the ISRO. In order to make the technology transfer process effective, ISRO has adopted a variety of functional and organizational policies that included awareness building measures, licensee selection methods, innovative contract systems, diverse transfer processes, post licencing services and feedback mechanisms. Besides analyzing these policies and their evolution, the paper discusses various models adopted for technology transfer and their impact on assessment. It also touches upon relevant issues relating to creating interface between public funded R&D and the private commercial enterprises. It suggests few models in which international cooperation could be pursued in this field.

  1. MDP: Reliable File Transfer for Space Missions

    NASA Technical Reports Server (NTRS)

    Rash, James; Criscuolo, Ed; Hogie, Keith; Parise, Ron; Hennessy, Joseph F. (Technical Monitor)

    2002-01-01

    This paper presents work being done at NASA/GSFC (Goddard Space Flight Center) by the Operating Missions as Nodes on the Internet (OMNI) project to demonstrate the application of the Multicast Dissemination Protocol (MDP) to space missions to reliably transfer files. This work builds on previous work by the OMNI project to apply Internet communication technologies to space communication. The goal of this effort is to provide an inexpensive, reliable, standard, and interoperable mechanism for transferring files in the space communication environment. Limited bandwidth, noise, delay, intermittent connectivity, link asymmetry, and one-way links are all possible issues for space missions. Although these are link-layer issues, they can have a profound effect on the performance of transport and application level protocols. MDP, a UDP (User Datagram Protocol)-based reliable file transfer protocol, was designed for multicast environments which have to address these same issues, and it has done so successfully. Developed by the Naval Research Lab in the mid 1990s, MDP is now in daily use by both the US Post Office and the DoD (Department of Defense). This paper describes the use of MDP to provide automated end-to-end data flow for space missions. It examines the results of a parametric study of MDP in a simulated space link environment and discusses the results in terms of their implications for space missions. Lessons learned are addressed, which suggest minor enhancements to the MDP user interface to add specific features for space mission requirements, such as dynamic control of data rate, and a checkpoint/resume capability. These are features that are provided for in the protocol, but are not implemented in the sample MDP application that was provided. A brief look is also taken at the status of standardization. A version of MDP known as NORM (Nack Oriented Reliable Multicast) is in the process of becoming an IETF (Internet Engineering Task Force) standard.

  2. High efficiency pump for space helium transfer

    NASA Technical Reports Server (NTRS)

    Hasenbein, Robert; Izenson, Michael G.; Swift, Walter L.; Sixsmith, Herbert

    1991-01-01

    A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium circulation in terrestrial facilities and for transfer of cryogenic rocket propellants in space.

  3. Unmanned and manned Mars missions - Aeroassist technology needs and issues

    NASA Technical Reports Server (NTRS)

    Willcockson, W. H.

    1989-01-01

    The critical aeroassist technologies are considered, with consideration given to the manned and unmanned Mars missions. Attention is given to the aerothermal characterization, the thermal-protection system (TPS), the guidance navigation and control systems, and atmospheric uncertainties. Particular consideration is given to the aerobrake assembly concepts for an unmanned Mars mission, and to programmatics.

  4. MDP: Reliable File Transfer for Space Missions

    NASA Technical Reports Server (NTRS)

    Rash, James; Criscuolo, Ed; Hogie, Keith; Parise, Ron; Hennessy, Joseph F. (Technical Monitor)

    2002-01-01

    This paper presents work being done at NASA/GSFC by the Operating Missions as Nodes on the Internet (OMNI) project to demonstrate the application of the Multicast Dissemination Protocol (MDP) to space missions to reliably transfer files. This work builds on previous work by the OMNI project to apply Internet communication technologies to space communication. The goal of this effort is to provide an inexpensive, reliable, standard, and interoperable mechanism for transferring files in the space communication environment. Limited bandwidth, noise, delay, intermittent connectivity, link asymmetry, and one-way links are all possible issues for space missions. Although these are link-layer issues, they can have a profound effect on the performance of transport and application level protocols. MDP, a UDP-based reliable file transfer protocol, was designed for multicast environments which have to address these same issues, and it has done so successfully. Developed by the Naval Research Lab in the mid 1990's, MDP is now in daily use by both the US Post Office and the DoD. This paper describes the use of MDP to provide automated end-to-end data flow for space missions. It examines the results of a parametric study of MDP in a simulated space link environment and discusses the results in terms of their implications for space missions. Lessons learned are addressed, which suggest minor enhancements to the MDP user interface to add specific features for space mission requirements, such as dynamic control of data rate, and a checkpoint/resume capability. These are features that are provided for in the protocol, but are not implemented in the sample MDP application that was provided. A brief look is also taken at the status of standardization. A version of MDP known as NORM (Neck Oriented Reliable Multicast) is in the process of becoming an IETF standard.

  5. Discrete Space Theory of Radiative Transfer: Application

    NASA Astrophysics Data System (ADS)

    Rao, M. Srinivasa

    2010-06-01

    The method of obtaining the solution of radiative transfer equation using discrete space theory (DST) is described with (1) interaction principle for different geometries (2) star product (3) calculation of radiation field at internal points. Some of the important steps to obtain the solution of radiative transfer equation in spherical symmetry are also mentioned. Applications of DST are discussed with their results in two cases (a) study of reflection effect in close binary systems and (b) to compute KI 769.9 nm emission line profiles from N-type stars.

  6. Discrete Space Theory of Radiative Transfer: Application

    NASA Astrophysics Data System (ADS)

    Rao, M. Srinivasa

    The method of obtaining the solution of radiative transfer equation using discrete space theory (DST) is described with (1) interaction principle for different geometries (2) star product (3) calculation of radiation field at internal points. Some of the important steps to obtain the solution of radiative transfer equation in spherical symmetry are also mentioned. Applications of DST are discussed with their results in two cases (a) study of reflection effect in close binary systems and (b) to compute KI 769.9 nm emission line profiles from N-type stars.

  7. Technology transfer from the space exploration initiative

    NASA Astrophysics Data System (ADS)

    Buden, David

    1992-01-01

    Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

  8. Technology transfer from the space exploration initiative

    SciTech Connect

    Buden, D.

    1991-06-14

    Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

  9. Technology transfer from the space exploration initiative

    SciTech Connect

    Buden, D.

    1991-06-14

    Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America`s competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.

  10. Vehicle/engine integration. [orbit transfer vehicles

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.; Vinopal, T. J.; Florence, D. E.; Michel, R. W.; Brown, J. R.; Bergeron, R. P.; Weldon, V. A.

    1984-01-01

    VEHICLE/ENGINE Integration Issues are explored for orbit transfer vehicles (OTV's). The impact of space basing and aeroassist on VEHICLE/ENGINE integration is discussed. The AOTV structure and thermal protection subsystem weights were scaled as the vehicle length and surface was changed. It is concluded that for increased allowable payload lengths in a ground-based system, lower length-to-diameter (L/D) is as important as higher mixture ration (MR) in the range of mid L/D ATOV's. Scenario validity, geometry constraints, throttle levels, reliability, and servicing are discussed in the context of engine design and engine/vehicle integration.

  11. Technology transfer within the NASA Goddard Space Flight Center

    NASA Technical Reports Server (NTRS)

    Plotkin, Henry H.

    1992-01-01

    Viewgraphs on technology transfer within the NASA Goddard Space Flight Center presented to Civil Space Technology Development workshop on technology transfer and effectiveness are provided. Topics covered include: obstacles to technology transfer; technology transfer improvement program at GSFC: communication between technology developers and users; and user feedback to technologists.

  12. Wireless Power Transfer for Space Applications

    NASA Technical Reports Server (NTRS)

    Ramos, Gabriel Vazquez; Yuan, Jiann-Shiun

    2011-01-01

    This paper introduces an implementation for magnetic resonance wireless power transfer for space applications. The analysis includes an equivalent impedance study, loop material characterization, source/load resonance coupling technique, and system response behavior due to loads variability. System characterization is accomplished by executing circuit design from analytical equations and simulations using Matlab and SPICE. The theory was validated by a combination of different experiments that includes loop material consideration, resonance coupling circuits considerations, electric loads considerations and a small scale proof-of-concept prototype. Experiment results shows successful wireless power transfer for all the cases studied. The prototype provided about 4.5 W of power to the load at a separation of -5 cm from the source using a power amplifier rated for 7 W.

  13. Space Biosensor Systems: Implications for Technology Transfer

    NASA Technical Reports Server (NTRS)

    Hines, J. W.; Somps, C. J.; Madou, M.; Imprescia, Clifford C. (Technical Monitor)

    1997-01-01

    To meet the need for continuous, automated monitoring of animal subjects, including; humans, during space flight, NASA is developing advanced physiologic sensor and biotelemetry system technologies. The ability to continuously track basic physiological parameters, such as heart rate, blood pH, and body temperature, in untethered subjects in space is a challenging task. At NASA's Ames Research Center, where a key focus is gravitational biology research, engineers have teamed with life scientists to develop wireless sensor systems for automated physiologic monitoring of animal models as small as the rat. This technology is also being adapted, in collaboration with medical professionals, to meet human clinical monitoring needs both in space and on the ground. Thus, these advanced monitoring technologies have important dual-use functions; they meet space flight data collection requirements and constraints, while concurrently addressing a number of monitoring and data acquisition challenges on the ground in areas of clinical monitoring and biomedical research. Additional applications for these and related technologies are being sought and additional partnerships established that enhance development efforts, reduce costs and facilitate technology infusion between the public and private sectors. This paper describes technology transfer and co-development projects that have evolved out of NASA's miniaturized, implantable chemical sensor development efforts.

  14. Spaced cognitive training promotes training transfer

    PubMed Central

    Wang, Zuowei; Zhou, Renlai; Shah, Priti

    2014-01-01

    Cognitive training studies yield wildly inconsistent results. One dimension on which studies vary is the scheduling of training sessions (Morrison and Chein, 2011). In this study, we systematically address whether or not spacing of practice influences training and transfer. We randomly assigned 115 fifth grade children to an active control group or one of four training groups who received working memory training based on a “running span” task (Zhao et al., 2011). All groups received the same total amount of training: 20 sessions of training with 60 trials for an average of 20 min per session. The training was spread across 2, 5, 10, or 20 days. The active control group received 20-min sessions of math instruction for 20 sessions. Before and after training participants in all five groups performed a single transfer test that assessed fluid intelligence, the Raven's Progressive Matrices Test. Overall, participants in all four training groups improved significantly on the training task (at least partially), as reflected by increased speed. More importantly, the only training group to show significant improvement on the Raven's was the group who had the greatest amount of spacing (20 days group) during training and improvement in this group was significantly higher than that of the control group. PMID:24782744

  15. Natural transfer of viable microbes in space.

    PubMed

    Mileikowsky, C; Cucinotta, F A; Wilson, J W; Gladman, B; Horneck, G; Lindegren, L; Melosh, J; Rickman, H; Valtonen, M; Zheng, J Q

    2000-06-01

    The possibility and probability of natural transfer of viable microbes from Mars to Earth and Earth to Mars traveling in meteoroids during the first 0.5 Ga and the following 4 Ga are investigated, including: --radiation protection against the galactic cosmic ray nuclei and the solar rays, dose rates as a function of the meteorite's radial column mass (radius x density), combined with dose rates generated by natural radioactivity within the meteorite; and survival curves for some bacterial species using NASA's HZETRN transport code --other factors affecting microbe survival: vacuum; central meteorite temperatures at launch, orbiting, and arrival; pressure and acceleration at launch; spontaneous DNA decay; metal ion migration --mean sizes and numbers of unshocked meteorites ejected and percentage falling on Earth, using current semiempirical results --viable flight times for the microbe species Bacillus subtilis and Deinococcus radiodurans R1 --the approximate fraction of microbes (with properties like the two species studied) viably arriving on Earth out of those ejected from Mars during the period 4 Ga BP to the present time, and during the 700 Ma from 4.5 to 3.8 Ga. Similarly, from Earth to Mars. The conclusion is that if microbes existed or exist on Mars, viable transfer to Earth is not only possible but also highly probable, due to microbes' impressive resistance to the dangers of space transfer and to the dense traffic of billions of martian meteorites which have fallen on Earth since the dawn of our planetary system. Earth-to-Mars transfer is also possible but at a much lower frequency. PMID:11543506

  16. Natural transfer of viable microbes in space

    NASA Technical Reports Server (NTRS)

    Mileikowsky, C.; Cucinotta, F. A.; Wilson, J. W.; Gladman, B.; Horneck, G.; Lindegren, L.; Melosh, J.; Rickman, H.; Valtonen, M.; Zheng, J. Q.

    2000-01-01

    The possibility and probability of natural transfer of viable microbes from Mars to Earth and Earth to Mars traveling in meteoroids during the first 0.5 Ga and the following 4 Ga are investigated, including: --radiation protection against the galactic cosmic ray nuclei and the solar rays, dose rates as a function of the meteorite's radial column mass (radius x density), combined with dose rates generated by natural radioactivity within the meteorite; and survival curves for some bacterial species using NASA's HZETRN transport code --other factors affecting microbe survival: vacuum; central meteorite temperatures at launch, orbiting, and arrival; pressure and acceleration at launch; spontaneous DNA decay; metal ion migration --mean sizes and numbers of unshocked meteorites ejected and percentage falling on Earth, using current semiempirical results --viable flight times for the microbe species Bacillus subtilis and Deinococcus radiodurans R1 --the approximate fraction of microbes (with properties like the two species studied) viably arriving on Earth out of those ejected from Mars during the period 4 Ga BP to the present time, and during the 700 Ma from 4.5 to 3.8 Ga. Similarly, from Earth to Mars. The conclusion is that if microbes existed or exist on Mars, viable transfer to Earth is not only possible but also highly probable, due to microbes' impressive resistance to the dangers of space transfer and to the dense traffic of billions of martian meteorites which have fallen on Earth since the dawn of our planetary system. Earth-to-Mars transfer is also possible but at a much lower frequency.

  17. Orbital transfer vehicle concept definition and systems analysis study. Volume 11: Study extension 2 results

    NASA Technical Reports Server (NTRS)

    Willcockson, W. H.

    1988-01-01

    Work conducted in the second extension of the Phase A Orbit Transfer Vehicle Concept Definition and Systems Analysis Study is summarized. Four major tasks were identified: (1) define an initial OTV program consistent with near term Civil Space Leadership Initiative missions; (2) develop program evolution to long term advanced missions; (3) investigate the implications of current STS safety policy on an Aft Cargo Carrier based OTV; and (4) expand the analysis of high entry velocity aeroassist. An increased emphasis on the breath of OTV applications was undertaken to show the need for the program on the basis of the expansion of the nation's capabilities in space.

  18. Geometerial description for a proposed aeroassist flight experiment vehicle

    NASA Technical Reports Server (NTRS)

    Cheatwood, F. M.; Dejarnette, F. J.; Hamilton, H. H., II

    1986-01-01

    One geometry currently under consideration for the Aeroassist Flight Experiment (AFE) vehicle is composed of several segments of simple general conics: an ellipsoidal nose tangent to an elliptical cone and a base skirt with the base plane raked relative to the body axis. An analytic representation for the body coordinates and first and second partial derivatives of this configuration has been developed. Equations are given which define the body radius and partial derivatives for a prescribed axial and circumferential position on the vehicle. The results for a sample case are tabulated and presented graphically.

  19. An approximate atmospheric guidance law for aeroassisted plane change maneuvers

    NASA Technical Reports Server (NTRS)

    Speyer, Jason L.; Crues, Edwin Z.

    1988-01-01

    An approximate optimal guidance law for the aeroassisted plane change problem is presented which is based upon an expansion of the Hamilton-Jacobi-Bellman equation with respect to the small parameter of Breakwell et al. (1985). The present law maximizes the final velocity of the reentry vehicle while meeting terminal constraints on altitude, flight path angle, and heading angle. The integrable zeroth-order solution found when the small parameter is set to zero corresponds to a solution of the problem where the aerodynamic forces dominate the inertial forces. Higher order solutions in the expansion are obtained from the solution of linear partial differential equations requiring only quadrature integration.

  20. Space transfer concepts and analysis for exploration missions

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A broad scoped and systematic study was made of space transfer concepts for human Lunar and Mars missions. Relevant space transportation studies were initiated to lead to further detailed activities in the following study period.

  1. Space transfer with ground-based laser/electric propulsion

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Stavnes, Mark; Oleson, Steve; Bozek, John

    1993-01-01

    A new method of providing power to space vehicles consists of using ground-based lasers to beam power to photovoltaic receivers in space. This can be used as a power source for electrically propelled orbital transfer vehicles.

  2. Surface flow and heating distributions on a cylinder in near wake of Aeroassist Flight Experiment (AFE) configuration at incidence in Mach 10 Air

    NASA Technical Reports Server (NTRS)

    Wells, William L.

    1990-01-01

    Experimental heat transfer distributions and surface streamline directions are presented for a cylinder in the near wake of the Aeroassist Flight Experiment forebody configuration. Tests were conducted in air at a nominal free stream Mach number of 10, with post shock Reynolds numbers based on model base height of 6,450 to 50,770, and angles of attack of 5, 0, -5, and -10 degrees. Heat transfer data were obtained with thin film resistance gage and surface streamline directions by the oil flow technique. Comparisons between measured values and predicted values were made by using a Navier-Stokes computer code.

  3. An advanced space rotary power transfer device

    NASA Astrophysics Data System (ADS)

    Jacobson, P. E.

    A new electrical signal and rotary power transfer device has recently evolved from ball-bearing and electrical-transfer technologies. This hybrid device, known as a roll ring, has been tested extensively since the late 1970s and has demonstrated important operational advantages in a wide variety of signal and power transfer configurations. A high power version has been developed and evaluated. This paper describes this latter roll ring configuration. The paper also summarizes test results.

  4. Navigation systems requirement analysis for the Aeroassist Flight Experiment (AFE)

    NASA Technical Reports Server (NTRS)

    Huang, K. H.; Chang, Ho-Pen; Wells, Eugene M.

    1990-01-01

    Navigation requirements for Aeroassist Flight Experiment (AFE) spacecraft passing through the earth's atmosphere have been studied using a 6-DOF dynamics model, an Inertial Measurement Unit model, a baseline AFE aeropass flight guidance logic, and a baseline AFE aeropass control model. The goal of this study is to determine, in a statistical sense, how much flight path angle error can be tolerated at Entry Interface (EI) and still have acceptable delta-V requirements at exit to position the AFE spacecraft for recovery. Assuming there is fuel available to produce 370 ft/sec of delta-V at atmospheric exit, a 3-sigma standard deviation in flight path angle error of 0.04 degree at EI would result in a 98 percent probability of mission success. In addition to the required delta-V at exit, other aeropass parameters such as maximum aeroheating rate, fuel consumption, and the science requirements affecting mission success are also investigated.

  5. Optimal control of aeroassisted plane change maneuver using feedback expansions

    NASA Technical Reports Server (NTRS)

    Mishne, D.; Speyer, J. L.

    1986-01-01

    A guidance law for an aeroassisted plane change maneuver is developed by an asymptotic expansion technique using a small parameter which essentially represents the ratio of the inertial forces to the atmospheric forces. This guidance law minimizes the energy loss while meeting terminal constraints on the altitude, flight path angle, and heading angle. By neglecting the inertial forces, the resulting optimization problem is integrable and can be determined in closed form. This zeroth-order solution is the first term in an asymptotic series solution of the Hamilton-Jacobi-Bellman equation. The remaining terms are determined from the solution of a first-order, linear partial differential equation whose solution requires only quadrature integration. Our initial results in using this guidance scheme are encouraging.

  6. Effect of Transition Aerodynamics on Aeroassist Flight Experiment Trajectories

    NASA Technical Reports Server (NTRS)

    Minier, Elizabeth A.; Suit, William T.

    1988-01-01

    Various transition methods are used here to study the viscous effects encountered in low density, hypersonic flight, through the transition from free molecular to continuum flow. Methods utilizing Viking data, Shuttle Orbiter data, a Potter number parameter, and a Shock Reynolds number were implemented in the Program to Optimize Simulated Trajectories (POST). Simulations of the Aeroassist Flight Experiment (AFE) using open loop guidance were used to assess the aerodynamic performance of the vehicle. A bank angle was found for each transition method that would result in a 200 nautical-mile apogee. Once this was done, the open loop guidance was replaced by the proposed guidance algorithm for the AFE. Simulations were again conducted using that guidance and the different transitions for comparison. For the gains used, the guidance system showed some sensitivity in apogee altitude to the transition method assumed, but the guidance was able to successfully complete the mission.

  7. Transfer of space technology to industry

    NASA Technical Reports Server (NTRS)

    Hamilton, J. T.

    1974-01-01

    Some of the most significant applications of the NASA aerospace technology transfer to industry and other government agencies are briefly outlined. The technology utilization program encompasses computer programs for structural problems, life support systems, fuel cell development, and rechargeable cardiac pacemakers as well as reliability and quality research for oil recovery operations and pollution control.

  8. Transfer of space technologies past and present: the Russian case.

    PubMed

    Pankova, Lyudmila

    2002-12-01

    Since the end of the 1980's transfer of government sponsored high technology space goods and services to other sectors, industry, and eventually non-government use has been a growing concern of the Russian policy makers. Today the real and functional transformation of this field is on the agenda. The paper is organized as follows. The first section analyzes the evolution of the common approach to technology transfer, looks at the main obstacles to this processes as a whole, and in the space sector in particular. The second section examines the Russian space R&D sector from the point of view of its role and place in the Russian scientific and technological base. New mechanisms of technology transfer are then considered. Here, problems of conversion, commercialization, dual-use, and internationalization are examined in the context of space technology transfer. Furthermore, issues of innovation in technology transfer are discussed. The new networks that are forming through which technologies diffuse is considered. The paper then turns to legislative and regulatory problems, including the discussion of the main principles of the Russian space transfer code, which is now being drafted. It is necessary to underline, that in the Russian case, official statistics still do not help analyze the question of technology transfer. PMID:14983845

  9. Dual Use Space Technology Transfer Conference Paper

    NASA Technical Reports Server (NTRS)

    Orndoff, Evelyne

    1994-01-01

    New textile fibers have been developed or modified to meet the complex and constraining criteria of space applications. The most common of these criteria are light weight, nonflammability or flame retardancy, and high strength and durability in both deep space environment and the oxygen enriched crew bay area of the spacecraft. The fibers which successfully pass the tests of flammability and toxicity, and display the desired mechanical properties are selected for space applications. Such advanced fibers developed for the Crew and Thermal Systems Division (CTSD) at the Johnson Space Center include 'Beta' fiber, heat stabilized polybenzimidazole and polyimide, as well as modified aramid Durette(TM), multi-fibrous Ortho(TM) fabric, and flame resistant cotton. The physical, mechanical, and chemical properties of these fibers are briefly discussed. The testing capabilities in the CTSD laboratory to ascertain some of the properties of these and other fibrous materials are also discussed. Most of these materials developed for spacecraft, space suit, and flight equipment applications have found other commercial applications. These advanced textile fibers are used mostly for aircraft, transportation, public buildings, hospitals, and protective clothing applications.

  10. Optimal control of orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Vinh, N. X.

    1983-01-01

    During the past two decades, considerable research effort has been spent to convincingly prove that the use of aerodynamic forces to assist in the orbital transfer can significantly reduce the fuel consumption as compared to the pure propulsive mode. Since in this aeroassisted mode, preliminary maneuvers in the vacuum effect the resulting performance in the atmospheric phase, and vice versa, the two, space and atmospheric maneuvers, are, to a great extent, coupled. This paper summarizes, via optimal control theory, the fundamental results in the problem of orbital transfer using combined propulsive and aerodynamic forces. For the atmospheric phase, the use of Chapman's variables reduced the number of the physical characteristics of the vehicle and the atmosphere to a minimum and hence allows a better generalization of the results. The paper concludes with some illustrative examples.

  11. Orbital transfer of large space structures with nuclear electric rockets

    NASA Technical Reports Server (NTRS)

    Silva, T. H.; Byers, D. C.

    1980-01-01

    This paper discusses the potential application of electric propulsion for orbit transfer of a large spacecraft structure from low earth orbit to geosynchronous altitude in a deployed configuration. The electric power was provided by the spacecraft nuclear reactor space power system on a shared basis during transfer operations. Factors considered with respect to system effectiveness included nuclear power source sizing, electric propulsion thruster concept, spacecraft deployment constraints, and orbital operations and safety. It is shown that the favorable total impulse capability inherent in electric propulsion provides a potential economic advantage over chemical propulsion orbit transfer vehicles by reducing the number of Space Shuttle flights in ground-to-orbit transportation requirements.

  12. Sales Training: Effects of Spaced Practice on Training Transfer

    ERIC Educational Resources Information Center

    Kauffeld, Simone; Lehmann-Willenbrock, Nale

    2010-01-01

    Purpose: The benefits of spaced training over massed training practice are well established in the laboratory setting. In a field study design with sales trainings, the purpose of this paper is to investigate the effects of spaced compared with massed practice on transfer quantity and quality, sales competence, and key figures.…

  13. Space transfer concepts and analysis for exploration missions

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Covered here is the second phase of a broad scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed issues that were raised during Phase 1, developed generic Mars missions profile analysis data, and conducted preliminary analysis of the Mars in-space transportation requirements and implementation from the Stafford Committee Synthesis Report.

  14. Vehicle for Space Transfer and Recovery (VSTAR), volume 1

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The Vehicle Space Transfer and Recovery (VSTAR) system is designed as a manned orbital transfer vehicle (MOTV) with the primary mission of Satellite Launch and Repair (SLR). VSTAR will provide for economic use of high altitude spaceflight for both the public and private sector. VSTAR components will be built and tested using earth based facilities. These components will then be launched using the space shuttle, into low earth orbit (LEO) where it will be constructed on a U.S. built space station. Once in LEO the vehicle components will be assembled in modules which can then be arranged in various configurations to perform the required missions.

  15. Status of advanced propulsion for space based orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.; Scheer, D. D.

    1986-01-01

    A new Orbital Transfer Vehicle (OTV) propulsion system will be required to meet the needs of space missions beyond the mid-1990's. As envisioned, the advanced OTV will be used in conjunction with Earth-to-orbit vehicles, Space Station, and Orbit Maneuvering Vehicle. The OTV will transfer men, large space structures, and conventional payloads between low Earth and higher energy orbits. Space probes carried by the OTV will continue the exploration of the solar system. When lunar bases are established, the OTV will be their transportation link to Earth. NASA is currently funding the development of technology for advanced propulsion concepts for future Orbital Transfer Vehicles. Progress in key areas during 1986 is presented.

  16. Message transfer service for space applications

    NASA Technical Reports Server (NTRS)

    Shames, P.

    2002-01-01

    Spacecraft applications that interact with on-board sensors, effectors, and major components have traditionally used private interfaces which are tightly bound to the interface details of the data links connecting these sub-systems. The latest spacecraft, which often include several powerful processors running real time operating systems, high-speed on-board networks, and intelligent peripherals, can support a more layered networked environment. Use of standard interfaces and networked elements is expected to yield reusable software and hardware components. Within CCSDS Panel 1K we have been developing such on-board interface standards. This paper will present a Message Transfer Service that defines a common API for use within a single spacecraft or among spacecraft flying in a constellation.

  17. Heat transfer from cylinders having closely spaced fins

    NASA Technical Reports Server (NTRS)

    Biermann, Arnold E

    1937-01-01

    The heat-transfer coefficients have been determined for five steel cylinders having fins 1.22 inches wide and the spacing between the fins ranging from 0.022 to 0.131 inch. The cylinders were tested with and without baffles in a wind tunnel; they were also tested enclosed in jackets with the cooling air supplied by a blower. A maximum heat transfer was reached at a fin space of about 0.45 inch for the cylinders tested with each of the three methods of cooling investigated. The rise in temperature of the air passing between the fins and the change in flow pattern were found to be important factors limiting the heat transfer that may be obtained by decreasing the fin space. The use of baffles for directing the air around the cylinders with closely spaced fins proved very effective in increasing the over-all heat-transfer coefficient, provided that the spacing was not appreciably less than that for maximum heat transfer.

  18. High-Temperature Adhesives for Thermally Stable Aero-Assist Technologies

    NASA Technical Reports Server (NTRS)

    Eberts, Kenneth; Ou, Runqing

    2013-01-01

    Aero-assist technologies are used to control the velocity of exploration vehicles (EVs) when entering Earth or other planetary atmospheres. Since entry of EVs in planetary atmospheres results in significant heating, thermally stable aero-assist technologies are required to avoid the high heating rates while maintaining low mass. Polymer adhesives are used in aero-assist structures because of the need for high flexibility and good bonding between layers of polymer films or fabrics. However, current polymer adhesives cannot withstand temperatures above 400 C. This innovation utilizes nanotechnology capabilities to address this need, leading to the development of high-temperature adhesives that exhibit high thermal conductivity in addition to increased thermal decomposition temperature. Enhanced thermal conductivity will help to dissipate heat quickly and effectively to avoid temperature rising to harmful levels. This, together with increased thermal decomposition temperature, will enable the adhesives to sustain transient high-temperature conditions.

  19. Technology transfer and evaluation for Space Station telerobotics

    NASA Technical Reports Server (NTRS)

    Price, Charles R.; Stokes, Lebarian; Diftler, Myron A.

    1994-01-01

    The international space station (SS) must take advantage of advanced telerobotics in order to maximize productivity and safety and to reduce maintenance costs. The Automation and Robotics Division at the NASA Lyndon B. Johnson Space Center (JSC) has designed, developed, and constructed the Automated Robotics Maintenance of Space Station (ARMSS) facility for the purpose of transferring and evaluating robotic technology that will reduce SS operation costs. Additionally, JSC had developed a process for expediting the transfer of technology from NASA research centers and evaluating these technologies in SS applications. Software and hardware system developed at the research centers and NASA sponsored universities are currently being transferred to JSC and integrated into the ARMSS for flight crew personnel testing. These technologies will be assessed relative to the SS baseline, and, after refinements, those technologies that provide significant performance improvements will be recommended as upgrades to the SS. Proximity sensors, vision algorithms, and manipulator controllers are among the systems scheduled for evaluation.

  20. GRAM Series of Atmospheric Models for Aeroentry and Aeroassist

    NASA Technical Reports Server (NTRS)

    Duvall, Aleta; Justus, C. G.; Keller, Vernon W.

    2005-01-01

    The eight destinations in the Solar System with sufficient atmosphere for either aeroentry or aeroassist, including aerocapture, are: Venus, Earth, Mars, Jupiter, Saturn; Uranus. and Neptune, and Saturn's moon Titan. Engineering-level atmospheric models for four of these (Earth, Mars, Titan, and Neptune) have been developed for use in NASA's systems analysis studies of aerocapture applications in potential future missions. Work has recently commenced on development of a similar atmospheric model for Venus. This series of MSFC-sponsored models is identified as the Global Reference Atmosphere Model (GRAM) series. An important capability of all of the models in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Example applications for Earth aeroentry and Mars aerocapture systems analysis studies are presented and illustrated. Current and planned updates to the Earth and Mars atmospheric models, in support of NASA's new exploration vision, are also presented.

  1. Space transfer with ground-based laser/electric propulsion

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Stavnes, Mark; Oleson, Steve; Bozek, John

    1992-01-01

    Ground-based high-power CW lasers can be used to beam power to photovoltaic receivers in space that furnish electricity to space vehicles; this energy can also be used to power electric-propulsion orbital transfer vehicles. An account is presently given of the anticipated requirements for the pulsed FEL lasers, large adaptive optics, photovoltaic receivers, and high specific impulse electrical propulsion. Preliminary system analysis results are presented.

  2. Space technology transfer to developing countries: opportunities and difficulties

    NASA Astrophysics Data System (ADS)

    Leloglu, U. M.; Kocaoglan, E.

    Space technology, with its implications on science, economy and security, is mostly chosen as one of the priority areas for technological development by developing countries. Most nations aspiring to begin playing in the space league prefer technology transfer programs as a first step. Decreasing initial costs by small satellite technology made this affordable for many countries. However, there is a long way from this first step to establishment of a reliable space industry that can both survive in the long term with limited financial support from the government and meet national needs. This is especially difficult when major defense companies of industrialized countries are merging to sustain their competitiveness. The prerequisites for the success are implementation of a well-planned space program and existence of industrialization that can support basic testing and manufacturing activities and supply qualified manpower. In this study, the difficulties to be negotiated and the vicious circles to be broken for latecomers, that is, developing countries that invest on space technologies are discussed. Especially, difficulties in the technology transfer process itself, brain drain from developing countries to industrialized countries, strong competition from big space companies for domestic needs, costs of establishing and maintaining an infrastructure necessary for manufacturing and testing activities, and finally, the impact of export control will be emphasized. We will also try to address how and to what extent collaboration can solve or minimize these problems. In discussing the ideas mentioned above, lessons learned from the BILSAT Project, a technology transfer program from the UK, will be referred.

  3. Midcourse Space Experiment Data Certification and Technology Transfer. Supplement 1

    NASA Technical Reports Server (NTRS)

    Pollock, David B.

    1998-01-01

    The University of Alabama in Huntsville contributes to the Technical Management of the Midcourse Space Experiment Program, to the Certification of the Level 2 data produced by the Midcourse Space Experiment's suite of in-orbit imaging radiometers, imaging spectro-radiometers and an interferometer and to the Transfer of the Midcourse Space Experiment Technology to other Government Programs. The Technical Management of the Midcourse Space Experiment Program is expected to continue through out the spacecraft's useful life time. The Transfer of Midcourse Space Experiment Technology to other government elements is expected to be on a demand basis by the United States Government and other organizations. The University, of Alabama Huntsville' contribution specifically supports the Principal Investigator's Executive Committee, the Deputy Principal Investigator for Data Certification and Technology Transfer team, the nine Ultraviolet Visible Imagers and Spectrographic Imagers (UVISI) and the Pointing and Alignment of all eleven of the science instruments. The science instruments effectively cover the 0.1 to 28 micron spectral region. The Midcourse Space Experiment spacecraft, launched April 24, 1996, is expected to have a 5 year useful lifetime. The cryogenically cooled IR sensor, SPIRIT III, performed through February, 1997 when its cryogen expired. A pre-launch, ground based calibration of the instruments provided a basis for the pre-launch certification of the Level 2 data base these instruments produce. With the spacecraft in-orbit the certification of the instrument's Level 2 data base was extended to the in-orbit environment.

  4. Space transfer concepts and analyses for exploration missions

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon R.

    1992-01-01

    The current technical effort is part of the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed the technical issues relating to the First Lunar Outpost (FLO) habitation vehicle with emphasis in the structure, power, life support system, and radiation environment.

  5. Space transfer concepts and analyses for exploration missions

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The current technical effort is part of the fourth phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addresses the costs of the First Lunar Outpost habitat and alternatives to this habitat.

  6. Design Considerations for Space Transfer Vehicles Using Solar Thermal Propulsion

    NASA Technical Reports Server (NTRS)

    Emrich, William J.

    1995-01-01

    The economical deployment of satellites to high energy earth orbits is crucial to the ultimate success of this nations commerical space ventures and is highly desirable for deep space planetary missions requiring earth escape trajectories. Upper stage space transfer vehicles needed to accomplish this task should ideally be simple, robust, and highly efficient. In this regard, solar thermal propulsion is particularly well suited to those missions where high thrust is not a requirement. The Marshall Space Flight Center is , therefore, currently engaged in defining a transfer vehicle employing solar thermal propulsion capable of transferring a 1000 lb. payload from low Earth orbit (LEO) to a geostationary Earth orbit (GEO) using a Lockheed launch vehicle (LLV3) with three Castors and a large shroud. The current design uses liquid hydrogen as the propellant and employs two inflatable 16 x 24 feet eliptical off-axis parabolic solar collectors to focus sunlight onto a tungsten/rhenium windowless black body type absorber. The concentration factor on this design is projected to be approximately 1800:1 for the primary collector and 2.42:1 for the secondary collector for an overall concentration factor of nearly 4400:1. The engine, which is about twice as efficient as the best currently available chemical engines, produces two pounds of thrust with a specific impulse (Isp) of 860 sec. Transfer times to GEO are projected to be on the order of one month. The launch and deployed configurations of the solar thermal upper stage (STUS) are depicted.

  7. Space transfer concepts and analyses for exploration missions, phase 3

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon R.

    1993-01-01

    This report covers the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed issues that were raised during Phase 2, developed generic Mars missions profile analysis data, and conducted preliminary analysis of the Mars in-space transportation requirements and implementation from Stafford Committee Synthesis Report. The major effort of the study was the development of the first Lunar Outpost (FLO) baseline which evolved from the Space Station Freedom Hab Module. Modifications for the First Lunar Outpost were made to meet mission requirements and technology advancements.

  8. Automated File Transfer and Storage Management Concepts for Space

    NASA Technical Reports Server (NTRS)

    Hogie, Keith; Criscuolo, Ed; Parise, Ron

    2004-01-01

    This presentation will summarize work that has been done to prototype and analyze approaches for automated file transfer and storage management for space missions. The concepts were prototyped in an environment with data files being generated at the target mission rates and stored in onboard files. The space-to-ground link was implemented using a channel simulator to introduce representative mission delays and errors. The system was operated for days with data files building up on the spacecraft and periodically being transferred to ground storage during a limited contact time. Overall performance was measured to identify limits under which the entire data volume could be transferred automatically while still fitting into the mission s limited contact time. The overall concepts, measurements, and results will be presented.

  9. International Space Station (ISS) Water Transfer Hardware Logistics

    NASA Technical Reports Server (NTRS)

    Shkedi, Brienne D.

    2006-01-01

    Water transferred from the Space Shuttle to the International Space Station (ISS) is generated as a by-product from the Shuttle fuel cells, and is generally preferred over the Progress which has to launch water from the ground. However, launch mass and volume are still required for the transfer and storage hardware. Some of these up-mass requirements have been reduced since ISS assembly began due to changes in the storage hardware (CWC). This paper analyzes the launch mass and volume required to transfer water from the Shuttle and analyzes the up-mass savings due to modifications in the CWC. Suggestions for improving the launch mass and volume are also provided.

  10. Visions of tomorrow: a focus on national space transportation issues; Proceedings of the Twenty-fifth Goddard Memorial Symposium, Greenbelt, MD, Mar. 18-20, 1987

    SciTech Connect

    Soffen, G.A.

    1987-01-01

    The present conference on U.S. space transportation systems development discusses opportunities for aerospace students in prospective military, civil, industrial, and scientific programs, current strategic conceptualization and program planning for future U.S. space transportation, the DOD space transportation plan, NASA space transportation plans, medium launch vehicle and commercial space launch services, the capabilities and availability of foreign launch vehicles, and the role of commercial space launch systems. Also discussed are available upper stage systems, future space transportation needs for space science and applications, the trajectory analysis of a low lift/drag-aeroassisted orbit transfer vehicle, possible replacements for the Space Shuttle, LEO to GEO with combined electric/beamed-microwave power from earth, the National Aerospace Plane, laser propulsion to earth orbit, and a performance analysis for a laser-powered SSTO vehicle.

  11. Ariane Transfer Vehicle - Logistic support to Space Station Freedom

    NASA Astrophysics Data System (ADS)

    Cougnet, C.; Ricaud, C.; Deutscher, N.

    The attractiveness of the Ariane 5 and Ariane transfer vehicle (ATV) is described: it avoids the one-sidedness of the National STS, it increases the lift capacity to meet the demands of the Space Station, and it offers a system independent of, but consistent with, the STS in providing backup contingency capability. The Ariane 5/ATV system is able to launch and transfer any cargo module to the Space Station Freedom (SSF) and dispose of it at the end of the mission. Consideration is given to Space Station and SSF logistic support, and ATV operations and design. Diagrams are provided to illustrate the ATV's requirements and capability; an ATV mission toward the SSF; ATV design and components; the ATV's attitude, layout, and the architecture of the main propulsion system and avionic; and the ATV's performance. It is demonstrated that the Ariane 5/ATV system would be an adequate complement to the NSTS for logistic support of the SSF.

  12. Mechanical pumps for superfluid helium transfer in space

    NASA Astrophysics Data System (ADS)

    Izenson, M. G.; Swift, W. L.

    1988-02-01

    Two alternate mechanical pump concepts have been identified for the transfer of superfluid helium in space. Both pumps provide flow at sufficient head and have operating characteristics suitable for the Space Infrared Telescope Facility (SIRTF) refill mission. One pump operates at a relatively low speed and utilizes mechanical roller bearings, while the other operates at a higher rotational speed using either electromagnetic or tilting pad gas-dynamic bearings. The use of gas bearings requires transfer of normal helium so that the gas pressure within the pump casing is high enough to operate the bearings. The operating characteristics of both pumps are predicted, the dimensions are estimated and major technology issues are identified. The major issues for each pump design are cavitation performance and bearing development. Roller bearings require quantified reliability for operation in space while electromagnetic bearings require basic development as well as a complex control system. The low speed pump has significantly poorer hydraulic efficiency than the high speed pump.

  13. Fluid physics, thermodynamics, and heat transfer experiments in space

    NASA Technical Reports Server (NTRS)

    Dodge, F. T.; Abramson, H. N.; Angrist, S. W.; Catton, I.; Churchill, S. W.; Mannheimer, R. J.; Otrach, S.; Schwartz, S. H.; Sengers, J. V.

    1975-01-01

    An overstudy committee was formed to study and recommend fundamental experiments in fluid physics, thermodynamics, and heat transfer for experimentation in orbit, using the space shuttle system and a space laboratory. The space environment, particularly the low-gravity condition, is an indispensable requirement for all the recommended experiments. The experiments fell broadly into five groups: critical-point thermophysical phenomena, fluid surface dynamics and capillarity, convection at reduced gravity, non-heated multiphase mixtures, and multiphase heat transfer. The Committee attempted to assess the effects of g-jitter and other perturbations of the gravitational field on the conduct of the experiments. A series of ground-based experiments are recommended to define some of the phenomena and to develop reliable instrumentation.

  14. Integrated Design System (IDS) Tools for the Spacecraft Aeroassist/Entry Vehicle Design Process

    NASA Technical Reports Server (NTRS)

    Olynick, David; Braun, Robert; Langhoff, Steven R. (Technical Monitor)

    1997-01-01

    The definition of the Integrated Design System technology focus area as presented in the NASA Information Technology center of excellence strategic plan is described. The need for IDS tools in the aeroassist/entry vehicle design process is illustrated. Initial and future plans for spacecraft IDS tool development are discussed.

  15. Midcourse Space Experiment Data Certification and Technology Transfer

    NASA Technical Reports Server (NTRS)

    Pollock, David B.

    1997-01-01

    The University of Alabama in Huntsville contributes to the Technical Management of the Midcourse Space Experiment Program, to the Certification of the Level 2 data produced by the Midcourse Space Experiment's suite of in-orbit imaging radiometers, imaging spectra-radiometers and an interferometer and to the Transfer of the Midcourse Space Experiment Technology to other Government Programs. The Technical Management of the Midcourse Space Experiment Program is expected to continue through out the spacecraft's useful life time, 5 years after its 1996 launch. The Transfer of Midcourse Space Experiment Technology to other government elements is expected to be on a demand basis by the United States Government and other organizations. The University of Alabama Huntsville' contribution specifically supports the nine Ultraviolet Visible Imagers and Spectrographic Imagers (UVISI) and the Pointing and Alignment of all eleven of the science instruments. The science instruments effectively cover the 0.1 to 28 micron spectral region. The Midcourse Space Experiment spacecraft, launched April 24, 1996, is expected to have a 5 year useful lifetime with a 12 month lifetime for the cryogenically cooled IR sensor. A pre-launch, ground based calibration of the instruments provided a basis for the pre-launch certification of the Level 2 data base these instruments produce. With the spacecraft in-orbit the certification of the instruments' Level 2 data base is being extended to the in-orbit environment.

  16. Aerothermal Instrumentation Loads To Implement Aeroassist Technology in Future Robotic and Human Missions to MARS and Other Locations Within the Solar System

    NASA Technical Reports Server (NTRS)

    Parmar, Devendra S.; Shams, Qamar A.

    2002-01-01

    The strategy of NASA to explore space objects in the vicinity of Earth and other planets of the solar system includes robotic and human missions. This strategy requires a road map for technology development that will support the robotic exploration and provide safety for the humans traveling to other celestial bodies. Aeroassist is one of the key elements of technology planning for the success of future robot and human exploration missions to other celestial bodies. Measurement of aerothermodynamic parameters such as temperature, pressure, and acceleration is of prime importance for aeroassist technology implementation and for the safety and affordability of the mission. Instrumentation and methods to measure such parameters have been reviewed in this report in view of past practices, current commercial availability of instrumentation technology, and the prospects of improvement and upgrade according to the requirements. Analysis of the usability of each identified instruments in terms of cost for efficient weight-volume ratio, power requirement, accuracy, sample rates, and other appropriate metrics such as harsh environment survivability has been reported.

  17. Transfer Learning across Feature-Rich Heterogeneous Feature Spaces via Feature-Space Remapping (FSR)

    PubMed Central

    Feuz, Kyle D.; Cook, Diane J.

    2016-01-01

    Transfer learning aims to improve performance on a target task by utilizing previous knowledge learned from source tasks. In this paper we introduce a novel heterogeneous transfer learning technique, Feature- Space Remapping (FSR), which transfers knowledge between domains with different feature spaces. This is accomplished without requiring typical feature-feature, feature instance, or instance-instance co-occurrence data. Instead we relate features in different feature-spaces through the construction of meta-features. We show how these techniques can utilize multiple source datasets to construct an ensemble learner which further improves performance. We apply FSR to an activity recognition problem and a document classification problem. The ensemble technique is able to outperform all other baselines and even performs better than a classifier trained using a large amount of labeled data in the target domain. These problems are especially difficult because in addition to having different feature-spaces, the marginal probability distributions and the class labels are also different. This work extends the state of the art in transfer learning by considering large transfer across dramatically different spaces. PMID:27019767

  18. Composite flexible insulation for thermal protection of space vehicles

    NASA Technical Reports Server (NTRS)

    Kourtides, Demetrius A.; Tran, Huy K.; Chiu, S. Amanda

    1991-01-01

    A composite flexible blanket insulation (CFBI) system considered for use as a thermal protection system for space vehicles is described. This flexible composite insulation system consists of an outer layer of silicon carbide fabric, followed by alumina mat insulation, and alternating layers of aluminized polyimide film and aluminoborosilicate scrim fabric. A potential application of this composite insulation would be as a thermal protection system for the aerobrake of the aeroassist space transfer vehicle (ASTV). It would also apply to other space vehicles subject to high convective and radiative heating during atmospheric entry. The thermal performance of this composite insulation as exposed to a simulated atmospheric entry environment in a plasma arc test facility is described. Other thermophysical properties which affect the thermal response of this composite insulation is included. It shows that this composite insulation is effective as a thermal protection system at total heating rates up to 30.6 W/sq cm.

  19. Research in space commercialization, technology transfer, and communications

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Research and internship programs in technology transfer, space commercialization, and information and communications policy are described. The intern's activities are reviewed. On-campus research involved work on the costs of conventional telephone technology in rural areas, an investigation of the lag between the start of a research and development project and the development of new technology, using NASA patent and patent waiver data, studies of the financial impact and economic prospects of a space operation center, a study of the accuracy of expert forecasts of uncertain quantities and a report on frequency coordination in the fixed and fixed satellite services at 4 and 6 GHz.

  20. Heat Transfer Analysis of a Closed Brayton Cycle Space Radiator

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.

    2007-01-01

    This paper presents a mathematical analysis of the heat transfer processes taking place in a radiator for a closed cycle gas turbine (CCGT), also referred to as a Closed Brayton Cycle (CBC) space power system. The resulting equations and relationships have been incorporated into a radiator sub-routine of a numerical triple objective CCGT optimization program to determine operating conditions yielding maximum cycle efficiency, minimum radiator area and minimum overall systems mass. Study results should be of interest to numerical modeling of closed cycle Brayton space power systems and to the design of fluid cooled radiators in general.

  1. Software Implements a Space-Mission File-Transfer Protocol

    NASA Technical Reports Server (NTRS)

    Rundstrom, Kathleen; Ho, Son Q.; Levesque, Michael; Sanders, Felicia; Burleigh, Scott; Veregge, John

    2004-01-01

    CFDP is a computer program that implements the CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol, which is an international standard for automatic, reliable transfers of files of data between locations on Earth and in outer space. CFDP administers concurrent file transfers in both directions, delivery of data out of transmission order, reliable and unreliable transmission modes, and automatic retransmission of lost or corrupted data by use of one or more of several lost-segment-detection modes. The program also implements several data-integrity measures, including file checksums and optional cyclic redundancy checks for each protocol data unit. The metadata accompanying each file can include messages to users application programs and commands for operating on remote file systems.

  2. Network transfer entropy and metric space for causality inference.

    PubMed

    Banerji, Christopher R S; Severini, Simone; Teschendorff, Andrew E

    2013-05-01

    A measure is derived to quantify directed information transfer between pairs of vertices in a weighted network, over paths of a specified maximal length. Our approach employs a general, probabilistic model of network traffic, from which the informational distance between dynamics on two weighted networks can be naturally expressed as a Jensen Shannon divergence. Our network transfer entropy measure is shown to be able to distinguish and quantify causal relationships between network elements, in applications to simple synthetic networks and a biological signaling network. We conclude with a theoretical extension of our framework, in which the square root of the Jensen Shannon Divergence induces a metric on the space of dynamics on weighted networks. We prove a convergence criterion, demonstrating that a form of convergence in the structure of weighted networks in a family of matrix metric spaces implies convergence of their dynamics with respect to the square root Jensen Shannon divergence metric. PMID:23767591

  3. Space transfer concepts and analysis for exploration missions

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon R.

    1992-01-01

    The current technical effort is part of the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed the technical issues relating to the First Lunar Outpost (FLO) habitation vehicle with emphasis on the structure, power, life support system, and radiation environment for a baseline habitat with specific alternatives for the baseline.

  4. Boundary emphasis transfer function generation based on HSL color space

    NASA Astrophysics Data System (ADS)

    Li, Xiao; Wu, Jianhuang; Luo, Shengzhou; Ma, Xin

    2011-10-01

    Direct volume rendering has been received much attention since it need not to extract geometric primitives for visualization and its performance is generally better than surface rendering. Transfer functions, which are used for mapping scalar field to optical properties, are of vital importance in obtaining a sensible rendering result from volume data. Though traditional color transfer functions are in RGB color space, HSL color space that conveys semantic meanings is more intuitive and user-friendly. In this paper, we present a novel approach aims to emphasize and distinguish strong boundaries between different materials. We achieve it by using data value, gradient magnitude and dimension of the volumetric data to set opacity. Then, through a linear map from data value, gradient magnitude and second derivative to hue, saturation and lightness respectively, a color transfer function is obtained in HSL color space. Experimental tests on real-world datasets indicate that our method could achieve desirable rendering results with revealing important boundaries between different structures and indicating data value's distribution in the volume by using different colors.

  5. Space-to-Space Power Beaming Enabling High Performance Rapid Geocentric Orbit Transfer

    NASA Technical Reports Server (NTRS)

    Dankanich, John W.; Vassallo, Corinne; Tadge, Megan

    2015-01-01

    The use of electric propulsion is more prevalent than ever, with industry pursuing all electric orbit transfers. Electric propulsion provides high mass utilization through efficient propellant transfer. However, the transfer times become detrimental as the delta V transitions from near-impulsive to low-thrust. Increasing power and therefore thrust has diminishing returns as the increasing mass of the power system limits the potential acceleration of the spacecraft. By using space-to-space power beaming, the power system can be decoupled from the spacecraft and allow significantly higher spacecraft alpha (W/kg) and therefore enable significantly higher accelerations while maintaining high performance. This project assesses the efficacy of space-to-space power beaming to enable rapid orbit transfer while maintaining high mass utilization. Concept assessment requires integrated techniques for low-thrust orbit transfer steering laws, efficient large-scale rectenna systems, and satellite constellation configuration optimization. This project includes the development of an integrated tool with implementation of IPOPT, Q-Law, and power-beaming models. The results highlight the viability of the concept, limits and paths to infusion, and comparison to state-of-the-art capabilities. The results indicate the viability of power beaming for what may be the only approach for achieving the desired transit times with high specific impulse.

  6. International data transfer for space very long baseline interferometry

    NASA Astrophysics Data System (ADS)

    Wiercigroch, Alexandria B.

    1994-11-01

    Space very long baseline interferometry (SVLBI) experiments using a TDRSS satellite have successfully demonstrated the capability of using spacecraft to extend the effective baseline length of VLBI observations beyond the diameter of the Earth, thereby improving the resolution for imaging of active galactic nuclei at centimeter wavelengths. As a result, two spacecraft dedicated to SVLBI, VSOP (Japan) and RadioAstron (Russia), are scheduled to be launched into high Earth orbit in 1996 and 1997. The success of these missions depends on the cooperation of the international community in providing support from ground tracking stations, ground radio telescopes, and correlation facilities. The timely exchange and monitoring of data among the participants requires a well-designed and automated international data transfer system. In this paper, we will discuss the design requirements, data types and flows, and the operational responsibilities associated with the SVLBI data transfer system.

  7. International data transfer for space very long baseline interferometry

    NASA Technical Reports Server (NTRS)

    Wiercigroch, Alexandria B.

    1994-01-01

    Space very long baseline interferometry (SVLBI) experiments using a TDRSS satellite have successfully demonstrated the capability of using spacecraft to extend the effective baseline length of VLBI observations beyond the diameter of the Earth, thereby improving the resolution for imaging of active galactic nuclei at centimeter wavelengths. As a result, two spacecraft dedicated to SVLBI, VSOP (Japan) and RadioAstron (Russia), are scheduled to be launched into high Earth orbit in 1996 and 1997. The success of these missions depends on the cooperation of the international community in providing support from ground tracking stations, ground radio telescopes, and correlation facilities. The timely exchange and monitoring of data among the participants requires a well-designed and automated international data transfer system. In this paper, we will discuss the design requirements, data types and flows, and the operational responsibilities associated with the SVLBI data transfer system.

  8. Perspectives on future space systems

    NASA Astrophysics Data System (ADS)

    Noor, Ahmed K.; Venneri, Samuel L.

    1994-02-01

    In response to increasing economic stresses and social concerns, the U.S. space program is being restructured, with a shift in mission strategy for future space activities and a change in design philosophy for space systems. NASA and DOD have established several national technology programs. They include Earth-to-Orbit (ETO) propulsion, the aeroassist flight experiment, telerobotics, space power, thermal management, control/structures interactions, space science sensor programs, and the small spacecraft technology program.

  9. Measured and predicted aerodynamic coefficients and shock shapes for Aeroassist Flight Experiment (AFE) configuration

    NASA Technical Reports Server (NTRS)

    Wells, William L.

    1989-01-01

    Two scaled models of the Aeroassist Flight Experiment (AFE) vehicle were tested in two air wind tunnels and one CF4 tunnel. The tests were to determine the static longitudinal aerodynamic characteristics, and shock shapes for the configuration in hypersonic continuum flow. The tests were conducted with a range of angle of attack to evaluate the effects of Mach number, Reynolds numbers, and normal shock density ratio.

  10. Space transfer vehicle concepts and requirements. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The objectives of the Space Transfer Vehicle (STV) Concepts and Requirements studies were to provide sensitivity data on usage, economics, and technology associated with new space transportation systems. The study was structured to utilize data on the emerging launch vehicles, the latest mission scenarios, and Space Exploration Initiative (SEI) payload manifesting and schedules, to define a flexible, high performance, cost effective, evolutionary space transportation system for NASA. Initial activities were to support the MSFC effort in the preparation of inputs to the 90 Day Report to the National Space Council (NSC). With the results of this study establishing a point-of-departure for continuing the STV studies in 1990, additional options and mission architectures were defined. The continuing studies will update and expand the parametrics, assess new cargo and manned ETO vehicles, determine impacts on the redefined Phase 0 Space Station Freedom, and to develop a design that encompasses adequate configuration flexibility to ensure compliance with on-going NASA study recommendations with major system disconnects. In terms of general requirements, the objectives of the STV system and its mission profiles will address crew safety and mission success through a failure-tolerant and forgiving design approach. These objectives were addressed through the following: engine-out capability for all mission phases; built-in-test for vehicle health monitoring to allow testing of all critical functions such as, verification of lunar landing and ascent engines before initiating the landing sequence; critical subsystems will have multiple strings for redundancy plus adequate supplies of onboard spares for removal and replacement of failed items; crew radiation protection; and trajectories that optimize lunar and Mars performance and flyby abort capabilities.

  11. Abstracting Attribute Space for Transfer Function Exploration and Design.

    PubMed

    Maciejewski, Ross; Jang, Yun; Woo, Insoo; Jänicke, Heike; Gaither, Kelly P; Ebert, David S

    2013-01-01

    Currently, user centered transfer function design begins with the user interacting with a one or two-dimensional histogram of the volumetric attribute space. The attribute space is visualized as a function of the number of voxels, allowing the user to explore the data in terms of the attribute size/magnitude. However, such visualizations provide the user with no information on the relationship between various attribute spaces (e.g., density, temperature, pressure, x, y, z) within the multivariate data. In this work, we propose a modification to the attribute space visualization in which the user is no longer presented with the magnitude of the attribute; instead, the user is presented with an information metric detailing the relationship between attributes of the multivariate volumetric data. In this way, the user can guide their exploration based on the relationship between the attribute magnitude and user selected attribute information as opposed to being constrained by only visualizing the magnitude of the attribute. We refer to this modification to the traditional histogram widget as an abstract attribute space representation. Our system utilizes common one and two-dimensional histogram widgets where the bins of the abstract attribute space now correspond to an attribute relationship in terms of the mean, standard deviation, entropy, or skewness. In this manner, we exploit the relationships and correlations present in the underlying data with respect to the dimension(s) under examination. These relationships are often times key to insight and allow us to guide attribute discovery as opposed to automatic extraction schemes which try to calculate and extract distinct attributes a priori. In this way, our system aids in the knowledge discovery of the interaction of properties within volumetric data. PMID:22508900

  12. Estimates of thermochemical relaxation lengths behind normal shock waves relevant to manned lunar and Mars return missions, the aeroassist flight experiment, and Mars entry

    NASA Technical Reports Server (NTRS)

    Howe, John T.

    1991-01-01

    Thermochemical relaxation distances behind the strong normal shock waves associated with vehicles that enter the Earth atmosphere upon returning from a manned lunar or Mars mission are estimated. The relaxation distances for a Mars entry are estimated as well, in order to highlight the extent of the relaxation phenomena early in currently envisioned space exploration studies. The thermochemical relaxation length for the Aeroassist Flight Experiment is also considered. These estimates provide an indication as to whether finite relaxation needs to be considered in subsequent detailed analyses. For the Mars entry, relaxation phenomena that are fully coupled to the flow field equations are used. The relaxation-distance estimates can be scaled to flight conditions other than those discussed.

  13. Space transfer vehicle concepts and requirements study, phase 2

    NASA Technical Reports Server (NTRS)

    Cannon, Jeffrey H.; Vinopal, Tim; Andrews, Dana; Richards, Bill; Weber, Gary; Paddock, Greg; Maricich, Peter; Bouton, Bruce; Hagen, Jim; Kolesar, Richard

    1992-01-01

    This final report is a compilation of the Phase 1 and Phase 2 study findings and is intended as a Space Transfer Vehicle (STV) 'users guide' rather than an exhaustive explanation of STV design details. It provides a database for design choices in the general areas of basing, reusability, propulsion, and staging; with selection criteria based on cost, performance, available infrastructure, risk, and technology. The report is organized into the following three parts: (1) design guide; (2) STV Phase 1 Concepts and Requirements Study Summary; and (3) STV Phase 2 Concepts and Requirements Study Summary. The overall objectives of the STV study were to: (1) define preferred STV concepts capable of accommodating future exploration missions in a cost-effective manner; (2) determine the level of technology development required to perform these missions in the most cost effective manner; and (3) develop a decision database of programmatic approaches for the development of an STV concept.

  14. Air Leakage and Air Transfer Between Garage and Living Space

    SciTech Connect

    Rudd, A.

    2014-09-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the Baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  15. Technology Transfer--Bridging Space and Society. The Students of the Technology Transfer Design Project Team (ISU Summer Session 1997).

    PubMed

    1997-01-01

    Strategies, policies and methods by which technologies can he cross-fertilized between the space and non-space sectors were examined by students of the design project "Technology Transfer--Bridging Space and Society". This project was undertaken by students attending the 1997 10th Anniversary Summer Session Program of the International Space University. General issues relating to transfer of technology were discussed including definitions and mechanisms (push, pull, interactive and pro-active). As well as looking at case studies and the impact of national policies on space agencies, the design project also sought to look at technology transfer on a country-by-country basis, selecting various countries for scrutiny and reporting on their technology transfer status. The project report shows how transfer of technology varies between nations and when analyzed with the case studies identifies the general strategies, policies and methods in use and how they can he improved. Finally, the report seeks to recommend certain issues to governments, space agencies and industrial organizations to facilitate the transfer of technology. These include the development of a generic metrics system and the implementation of better appropriate procedures and mechanisms for a positive diffusion process between space and non-space sectors. PMID:11541148

  16. Bacterial plasmid transfer under space flight conditions: The Mobilisatsia experience

    NASA Astrophysics Data System (ADS)

    de Boever, P.; Ilyin, V.; Mahillon, J.; Mergeay, M.

    Background Microorganisms are subject to a genetic evolution which may lead to the capacity to colonize new environments and to cause infections Central players in this evolutionary process are mobile genetic elements phages plasmids and transposons The latter help to mobilize and reorganize genes be it within a given genome intragenomic mobility or between bacterial cells intercellular mobility Confined environment and space flight related factors such as microgravity and cosmic radiation may influence the frequency with which mobile genetic elements are exchanged between microorganisms Aim Within the frame of the Mobilisatsia experiment a triparental microbial plasmid transfer was promoted aboard the International Space Station ISS The efficiency of the plasmid exchange process was compared with a synchronously performed ground control experiment An experiment was carried out with well-characterized Gram-negative test strains and one experiment was done with Gram-positive test strains Results The experiment took place during the Soyouz Mission 8 to the ISS from April 19th until April 30th 2004 Liquid cultures of the bacterial strains Cupriavidus metallidurans AE815 final recipient Escherichia coli CM1962 carrying a mobilisable vector with a nickel-resistance marker and E coli CM140 carrying the Broad Host Range plasmid RP4 for the Gram-negative experiment and Bacillus thuringiensis Bti AND931 carrying the conjugative plasmid pXO16 Bti 4Q7 with mobilisable vector pC194 carrying a resistance to chloramphenicol and Bti GBJ002

  17. Reentry heat transfer analysis of the space shuttle orbiter

    NASA Technical Reports Server (NTRS)

    Ko, W. L.; Quinn, R. D.; Gong, L.

    1982-01-01

    A structural performance and resizing finite element thermal analysis computer program was used in the reentry heat transfer analysis of the space shuttle. Two typical wing cross sections and a midfuselage cross section were selected for the analysis. The surface heat inputs to the thermal models were obtained from aerodynamic heating analyses, which assumed a purely turbulent boundary layer, a purely laminar boundary layer, separated flow, and transition from laminar to turbulent flow. The effect of internal radiation was found to be quite significant. With the effect of the internal radiation considered, the wing lower skin temperature became about 39 C (70 F) lower. The results were compared with fight data for space transportation system, trajectory 1. The calculated and measured temperatures compared well for the wing if laminar flow was assumed for the lower surface and bay one upper surface and if separated flow was assumed for the upper surfaces of bays other than bay one. For the fuselage, good agreement between the calculated and measured data was obtained if laminar flow was assumed for the bottom surface. The structural temperatures were found to reach their peak values shortly before touchdown. In addition, the finite element solutions were compared with those obtained from the conventional finite difference solutions.

  18. Reentry heat transfer analysis of the space shuttle orbiter

    NASA Astrophysics Data System (ADS)

    Ko, W. L.; Quinn, R. D.; Gong, L.

    A structural performance and resizing finite element thermal analysis computer program was used in the reentry heat transfer analysis of the space shuttle. Two typical wing cross sections and a midfuselage cross section were selected for the analysis. The surface heat inputs to the thermal models were obtained from aerodynamic heating analyses, which assumed a purely turbulent boundary layer, a purely laminar boundary layer, separated flow, and transition from laminar to turbulent flow. The effect of internal radiation was found to be quite significant. With the effect of the internal radiation considered, the wing lower skin temperature became about 39 C (70 F) lower. The results were compared with fight data for space transportation system, trajectory 1. The calculated and measured temperatures compared well for the wing if laminar flow was assumed for the lower surface and bay one upper surface and if separated flow was assumed for the upper surfaces of bays other than bay one. For the fuselage, good agreement between the calculated and measured data was obtained if laminar flow was assumed for the bottom surface. The structural temperatures were found to reach their peak values shortly before touchdown. In addition, the finite element solutions were compared with those obtained from the conventional finite difference solutions.

  19. Air Leakage and Air Transfer Between Garage and Living Space

    SciTech Connect

    Rudd, Armin

    2014-09-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed.

  20. 33 CFR 127.105 - Layout and spacing of marine transfer area for LNG.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... spacing of marine transfer area for LNG. (a) LNG impounding spaces must be located so that the heat flux... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Layout and spacing of marine transfer area for LNG. 127.105 Section 127.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

  1. 33 CFR 127.105 - Layout and spacing of marine transfer area for LNG.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... spacing of marine transfer area for LNG. (a) LNG impounding spaces must be located so that the heat flux... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Layout and spacing of marine transfer area for LNG. 127.105 Section 127.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

  2. 33 CFR 127.105 - Layout and spacing of marine transfer area for LNG.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... spacing of marine transfer area for LNG. (a) LNG impounding spaces must be located so that the heat flux... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Layout and spacing of marine transfer area for LNG. 127.105 Section 127.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT...

  3. Space transfer vehicle concepts and requirements study. Volume 2, book 1: STV concept definition and evaluation

    NASA Technical Reports Server (NTRS)

    Weber, Gary A.

    1991-01-01

    The topics covered include the following: mission analysis; initial and evolutionary space transfer vehicle (STV) concept definition; configuration and subsystem trade studies; and operations and logistics.

  4. NASA's In-Space Propulsion Technology Program

    NASA Astrophysics Data System (ADS)

    Johnson, L.; Robinson, J.

    2004-11-01

    NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum theoretical efficiencies have almost been reached and they are insufficient to meet needs for many ambitious science missions currently being considered. The In-Space Propulsion Technology Program's technology portfolio includes many advanced propulsion systems. From the next generation ion propulsion system operating in the 5 - 10 kW range, to advanced cryogenic propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called, ``propellantless" because they do not require on-board fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails, electrodynamic and momentum transfer tethers, aeroassist, and aerocapture. This paper will provide an overview of both propellantless and propellant-based advanced propulsion technologies, and NASA's plans for advancing them as part of the \\$60M per year In-Space Propulsion Technology Program. Solar sails and aerocapture are candidates for flight validation as early as 2008 in partnership with NASA's New Millennium Program.

  5. 33 CFR 127.1105 - Layout and spacing of marine transfer area for LHG.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... transfer area for LHG. 127.1105 Section 127.1105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Construction § 127.1105 Layout and spacing of marine transfer area for LHG. Each new waterfront facility handling LHG, and all new construction in the marine transfer area for LHG of each existing facility,...

  6. Helium Evolution from the Transfer of Helium Saturated Propellant in Space

    NASA Technical Reports Server (NTRS)

    Nguyen, Bich N.

    2000-01-01

    Helium evolution from the transfer of helium saturated propellant in space is quantified to determine its impact from creating a two-phase mixture in the transfer line. The transfer line is approximately 1/2 inch in diameter and 2400 inches in length comprised of the Fluid Interconnect System (FICS), the Orbiter Propellant Transfer System (OPTS) and the International Space Station (ISS) Propulsion Module (ISSPM). The propellant transfer rate is approximately two to three gallons per minute, and the supply tank pressure is maintained at approximately 250 psig.

  7. Radiation Heat Transfer Procedures for Space-Related Applications

    NASA Technical Reports Server (NTRS)

    Chai, John C.

    2000-01-01

    Over the last contract year, a numerical procedure for combined conduction-radiation heat transfer using unstructured grids has been developed. As a result of this research, one paper has been published in the Numerical Heat Transfer Journal. One paper has been accepted for presentation at the International Center for Heat and Mass Transfer's International Symposium on Computational Heat Transfer to be held in Australia next year. A journal paper is under review by my NASA's contact. A conference paper for the ASME National Heat Transfer conference is under preparation. In summary, a total of four (4) papers (two journal and two conference) have been published, accepted or are under preparation. There are two (2) to three (3) more papers to be written for the project. In addition to the above publications, one book chapter, one journal paper and six conference papers have been published as a result of this project. Over the last contract year, the research project resulted in one Ph.D. thesis and partially supported another Ph.D. student. My NASA contact and myself have formulated radiation heat transfer procedures for materials with different indices of refraction and for combined conduction-radiation heat transfer. We are trying to find other applications for the procedures developed under this grant.

  8. Research in space commercialization, technology transfer, and communications, volume 2

    NASA Technical Reports Server (NTRS)

    Dunn, D. A.; Agnew, C. E.

    1983-01-01

    Spectrum management, models for evaluating communication systems, the communications regulatory environment, expert prediction and consensus, remote sensing, and manned space operations research are discussed.

  9. High-accuracy global time and frequency transfer with a space-borne hydrogen maser clock

    NASA Technical Reports Server (NTRS)

    Decher, R.; Allan, D. W.; Alley, C. O.; Baugher, C.; Duncan, B. J.; Vessot, R. F. C.; Winkler, G. M. R.

    1983-01-01

    A proposed system for high-accuracy global time and frequency transfer using a hydrogen maser clock in a space vehicle is discussed. Direct frequency transfer with a accuracy of 10 to the minus 14th power and time transfer with an estimated accuracy of 1 nsec are provided by a 3-link microwave system. A short pulse laser system is included for subnanosecond time transfer and system calibration. The results of studies including operational aspects, error sources, data flow, system configuration, and implementation requirements for an initial demonstration experiment using the Space Shuttle are discussed.

  10. Self-lubricating polymer composites and polymer transfer film lubrication for space applications

    NASA Technical Reports Server (NTRS)

    Fusaro, Robert L.

    1990-01-01

    The use of self-lubricating polymers and polymer composites in space is somewhat limited today. In general, they are only used when other methods are inadequate. There is potential, however, for these materials to make a significant impact on future space missions if properly utilized. Some of the different polymers and fillers used to make self-lubricating composites are surveyed. The mechanisms of composite lubrication and wear, the theory behind transfer film lubricating mechanisms, and some factors which affect polymer composite wear and transfer are examined. In addition, some of the current space tribology application areas for self-lubricating polymer composites and polymer transfer are mentioned.

  11. Research in space commercialization, technology transfer and communications, vol. 2

    NASA Technical Reports Server (NTRS)

    Dunn, D. A.; Agnew, C. E.

    1983-01-01

    Spectrum management, models for evaluating communications systems, and implications of communications regulations for NASA are considered as major parts of communications policy. Marketing LANDSAT products in developing countries, a political systems analysis of LANDSAT, and private financing and operation of the space operations center (space station) are discussed. Investment requirements, risks, government support, and other primary business and management considerations are examined.

  12. NASA's In-Space Propulsion Program

    NASA Technical Reports Server (NTRS)

    Johnson, Les

    2003-01-01

    In order to implement the ambitious science and exploration missions planned over the next several decades, improvements in in-space transportation and propulsion technologies must be achieved. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs. Future missions will require 2 to 3 times more total change in velocity over their mission lives than the NASA Solar Electric Technology Application Readiness (NSTAR) demonstration on the Deep Space 1 mission. New opportunities to explore beyond the outer planets and to the stars will require unparalleled technology advancement and innovation. NASA's In-Space Propulsion (ISP) Program is investing in technologies to meet these needs. The ISP technology portfolio includes many advanced propulsion systems. From the next generation ion propulsion system operating in the 5-10 kW range, to advanced cryogenic propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called, propellantless because they do not require on-board fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar and plasma sails, electrodynamic and momentum transfer tethers, and aeroassist and aerocapture. An overview of both propellantless and propellant-based advanced propulsion technologies, and NASA s plans for advancing them, will be provided.

  13. Reliable transfer of data from ground to space

    NASA Technical Reports Server (NTRS)

    Brosi, Fred

    1993-01-01

    This paper describes the problems involved in uplink of data from control centers on the ground to spacecraft, and explores the solutions to those problems, past. present. and future. The evolution of this process, from simple commanding to transfer of large volumes of data and commands is traced. The need for reliable end-to-end protocols for commanding and file transfer is demonstrated, and the shortcomings of both existing telecommand protocols and commercial products to meet this need are discussed. Recent developments in commercial protocols that may be adaptable to the mentioned operations environment are surveyed, and current efforts to develop a suite of protocols for reliable transfer in this environment are presented.

  14. A Compact Remote Heat Transfer Device for Space Cryocoolers

    NASA Astrophysics Data System (ADS)

    Yan, T.; Zhao, Y.; Liang, T.

    In this paper a compact remote heat transfer device (CRHD) for cryocoolers is proposed. This device is especially attractive in cases where cryocoolers are not easy to set near the heat source, generally the infrared sensor. The CRHD is designed on basis of the concept of loop heat pipes, while the primary evaporator is located near the cryocooler cold head and a simple tube-in-tube secondary evaporator is remotely located and thermally connected with the heat source for cooling. With such a device a cooling power of 1 W is achieved across a heat transfer distance of about 2 m. The major problem of this device is the low heat transfer efficiency (1 W of net cooling power at the cost of about 7 W of cooling power from the cryocooler), and in the future a secondary wicked evaporator will be used instead of the tube-in-tube evaporator in order to improve the efficiency.

  15. A computational study of the flowfield surrounding the Aeroassist Flight Experiment vehicle

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.; Greene, Francis A.

    1987-01-01

    A symmetric total variation diminishing (STVD) algorithm has been applied to the solution of the three-dimensional hypersonic flowfield surrounding the Aeroassist Flight Experiment (AFE) vehicle. Both perfect-gas and chemical nonequilibrium models have been used. The perfect-gas flows were computed at two different Reynolds numbers, including a flight trajectory point at maximum dynamic pressure, and on two different grids. Procedures for coupling the solution of the species continuity equations with the Navier-Stokes equations in the presence of chemical nonequilibrium are reviewed and tested on the forebody of the AFE and on the complete flowfield assuming noncatalytic wall and no species diffusion. Problems with the STVD algorithm unique to flows with variable thermodynamic properties (real gas) are identified and algorithm modifications are suggested. A potential heating problem caused by strong flow impingement on the nozzle lip in the near wake at 0-deg angle of attack has been identified.

  16. Free-molecule-flow force and moment coefficients of the aeroassist flight experiment vehicle

    NASA Technical Reports Server (NTRS)

    Blanchard, Robert C.; Hinson, Edwin W.

    1989-01-01

    Calculated results for the aerodynamic coefficients over the range of + or - 90 deg in both pitch and yaw attitude angles for the Aeroassist Flight Experiment (AFE) vehicle in free molecule flow are presented. The AFE body is described by a large number of small flat plate surface elements whose orientations are established in a wind axes coordinate system through the pitch and yaw attitude angles. Lift force, drag force, and three components of aerodynamic moment about a specified point are computed for each element. The elemental forces and moments are integrated over the entire body, and total force and moment coefficients are computed. The coefficients are calculated for the two limiting gas-surface molecular collision conditions, namely, specular and diffuse, which assume zero and full thermal accommodation of the incoming gas molecules with the surface, respectively. The individual contribution of the shear stress and pressure terms are calculated and also presented.

  17. Matched asymptotic expansion of the Hamilton-Jacobi-Bellman equation for aeroassisted plane-change maneuvers

    NASA Technical Reports Server (NTRS)

    Calise, Anthony J.; Melamed, Nahum

    1993-01-01

    In this paper we develop a general procedure for constructing a matched asymptotic expansion of the Hamilton-Jacobi-Bellman equation based on the method of characteristics. The development is for a class of perturbation problems whose solution exhibits two-time-scale behavior. A regular expansion for problems of this type is inappropriate since it is not uniformly valid over a narrow range of the independent variable. Of particular interest here is the manner in which matching and boundary conditions are enforced when the expansion is carried out to first order. Two cases are distinguished - one where the left boundary condition coincides with or lies to the right of the singular region and one where the left boundary condition lies to the left of the singular region. A simple example is used to illustrate the procedure, and its potential application to aeroassisted plane change is described.

  18. Definition of technology development missions for early space station, orbit transfer vehicle servicing, volume 2

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Propellant transfer, storage, and reliquefaction TDM; docking and berthing technology development mission; maintenance technology development mission; OTV/payload integration, space station interface/accommodations; combined TDM conceptual design; programmatic analysis; and TDM equipment usage are discussed.

  19. Characterization of heat transfer in nutrient materials. [space flight feeding

    NASA Technical Reports Server (NTRS)

    Witte, L. C.

    1985-01-01

    The processing and storage of foodstuffs in zero-g environments such as in Skylab and the space shuttle were investigated. Particular attention was given to the efficient heating of foodstuffs. The thermophysical properties of various foods were cataloged and critiqued. The low temperature storage of biological samples as well as foodstuffs during shuttle flights was studied. Research and development requirements related to food preparation and storage on the space station are discussed.

  20. Options for organization and operation of space applications transfer centers

    NASA Technical Reports Server (NTRS)

    Robinson, A. C.; Madigan, J. A.

    1976-01-01

    The benefits of developing regional facilities for transfer of NASA developed technology are discussed. These centers are designed to inform, persuade, and serve users. Included will be equipment for applications and demonstrations of the processes, a library, training facilities, and meeting rooms. The staff will include experts in the various techniques, as well as personnel involved in finding and persuading potential users.

  1. Flexible Visual Statistical Learning: Transfer across Space and Time

    ERIC Educational Resources Information Center

    Turk-Browne, Nicholas B.; Scholl, Brian J.

    2009-01-01

    The environment contains considerable information that is distributed across space and time, and the visual system is remarkably sensitive to such information via the operation of visual statistical learning (VSL). Previous VSL studies have focused on establishing what kinds of statistical relationships can be learned but have not fully explored…

  2. Exploration Challenges: Transferring Ground Repair Techniques to Space Flight Application

    NASA Technical Reports Server (NTRS)

    McLemore, Carole A.; Kennedy, James P.; Rose, Frederick A.; Evans, Brian W.

    2007-01-01

    Fulfilling NASA's Vision for Space Exploration will demand an extended presence in space at distances from our home planet that exceed our current experience in space logistics and maintenance. The ability to perform repairs in lieu of the customary Orbital Replacement Unit (ORU) process where a faulty part is replaced will be elevated from contingency to routine to sustain operations. The use and cost effectiveness of field repairs for ground based operations in industry and the military have advanced with the development of technology in new materials, new repair techniques and new equipment. The unique environments, accessibility constraints and Extra Vehicular Activity (EVA) issues of space operations will require extensive assessment and evolution of these technologies to provide an equivalent and expected level of assurance to mission success. Challenges include the necessity of changes in design philosophy and policy, extremes in thermal cycling, disruptive forces (such as static charge and wind entrainment) on developed methods for control of materials, dramatically increased volatility of chemicals for cleaning and other compounds due to extremely low pressures, the limits imposed on dexterity and maneuverability by current EVA equipment and practices, and the necessity of unique verification methodology. This paper describes these challenges in and discusses the effects on the established ground techniques for repair. The paper also describes the leading repair methodology candidates and their beneficial attributes for resolving these issues with the evolution of technology.

  3. The General Discussion on Thermal Technologies in Advanced Space Transfer Vehicles

    NASA Astrophysics Data System (ADS)

    Qi, Feng; Wang, Guo-hui

    2016-07-01

    In recent years, the boundary of space exploration has been wider and wider. So the demand of new-generation spacecrafts, carriers and transfer vehicles becomes urged. In this article, thermal questions and first-stage counter-measure technical methods and the relative important recent improvements in these methods are discussed about two important types of new conceptive Space Transfer Vehicles (STVs), the nuclear-thermal propelling STV and laser propelled STV, especially on the heat generation, heat collection, heat transfer and heat control. At the end of this article, pieces of advice and several predictions are put forward, generally and principally.

  4. NASA In-Space Propulsion Technology Program: Overview and Update

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Alexander, Leslie; Baggett, Randy M.; Bonometti, Joseph A.; Herrmann, Melody; James, Bonnie F.; Montgomery, Sandy E.

    2004-01-01

    NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum theoretical efficiencies have almost been reached and they are insufficient to meet needs for many ambitious science missions currently being considered. The In-Space Propulsion Technology Program's technology portfolio includes many advanced propulsion systems. From the next-generation ion propulsion system operating in the 5- to 10-kW range to aerocapture and solar sails, substantial advances in - spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called 'propellantless' because they do not require onboard fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails, electrodynamic and momentum transfer.tethers, aeroassist and aerocapture. This paper will provide an overview of both propellantless and propellant-based advanced propulsion technologies, as well as NASA's plans for advancing them as part of the In-Space Propulsion Technology Program.

  5. NASA's In-Space Propulsion Technology Program: Overview and Update

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Alexander, Leslie; Baggett, Randy M.; Bonometti, Joseph A.; Herrmann, Melody; James, Bonnie F.; Montgomery, Sandy E.

    2004-01-01

    NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum theoretical efficiencies have almost been reached and they are insufficient to meet needs for many ambitious science missions currently being considered. The In-Space Propulsion Technology Program s technology portfolio includes many advanced propulsion systems. From the next-generation ion propulsion system operating in the 5- to 10-kW range to aerocapture and solar sails, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals ase the environment of space itself for energy and propulsion and are generically called 'propellantless' because they do not require onboard fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails, electrodynamic and momentum transfer tethers, aeroassist, and aerocapture. This paper will provide an overview of both propellantless and propellant-based advanced propulsion technologies, as well as NASA s plans for advancing them as part of the In-Space Propulsion Technology Program.

  6. NASA's In-Space Propulsion Technology Program: Overview and Status

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Alexander, Leslie; Baggett, Randy; Bonometti, Joe; Herrmann, Melody; James, Bonnie; Montgomery, Sandy

    2004-01-01

    NASA's In-Space Propulsion Technology Program is investing in technologies that have the potential to revolutionize the robotic exploration of deep space. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs and, in some cases, enable missions previously considered impossible. Continued reliance on conventional chemical propulsion alone will not enable the robust exploration of deep space - the maximum theoretical efficiencies have almost been reached and they are insufficient to meet needs for many ambitious science missions currently being considered. The In-Space Propulsion Technology Program s technology portfolio includes many advanced propulsion systems. From the next generation ion propulsion system operating in the 5 - 10 kW range, to advanced cryogenic propulsion, substantial advances in spacecraft propulsion performance are anticipated. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called, 'propellantless' because they do not require onboard fuel to achieve thrust. Propellantless propulsion technologies include scientific innovations such as solar sails, electrodynamic and momentum transfer tethers, aeroassist, and aerocapture. This paper will provide an overview of both propellantless and propellant-based advanced propulsion technologies, and NASA s plans for advancing them as part of the $60M per year In-Space Propulsion Technology Program.

  7. NASA Office of Aeronautics and Space Technology Summer Workshop. Volume 1: Data processing and transfer panel

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The data processing and transfer technology areas that need to be developed and that could benefit from space flight experiments are identified. Factors considered include: user requirements, concepts in 'Outlook for Space', and cost reduction. Major program thrusts formulated are an increase in end-to-end information handling and a reduction in life cycle costs.

  8. Technology for Future NASA Missions: Civil Space Technology Initiative (CSTI) and Pathfinder

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Information is presented in viewgraph form on a number of related topics. Information is given on orbit transfer vehicles, spacecraft instruments, spaceborne experiments, university/industry programs, spacecraft propulsion, life support systems, cryogenics, spacecraft power supplies, human factors engineering, spacecraft construction materials, aeroassist, aerobraking and aerothermodynamics.

  9. OAST space research and technology applications: Technology transfer successes

    NASA Technical Reports Server (NTRS)

    Reck, Gregory M.

    1992-01-01

    The ultimate measure of success in the Space Research and Technology Program is the incorporation of a technology into an operational mission. Charts are presented that describe technology products which OAST has helped support that (1) have been used in a space mission, (2) have been incorporated into the baseline design of a flight system in the development phase, or (3) have been picked up by a commercial or other non-NASA user. We hope that these examples will demonstrate the value of investment in technology. Pictured on the charts are illustrations of the technology product, the mission or user which has incorporated the technology, and where appropriate, results from the mission itself.

  10. Momentum Transfer by Laser Ablation of Irregularly Shaped Space Debris

    SciTech Connect

    Liedahl, D A; Libby, S B; Rubenchik, A

    2010-02-04

    Proposals for ground-based laser remediation of space debris rely on the creation of appropriately directed ablation-driven impulses to either divert the fragment or drive it into an orbit with a perigee allowing atmospheric capture. For a spherical fragment, the ablation impulse is a function of the orbital parameters and the laser engagement angle. If, however, the target is irregularly shaped and arbitrarily oriented, new impulse effects come into play. Here we present an analysis of some of these effects.

  11. Midcourse Space Experiment Data Certification and Technology Transfer

    NASA Technical Reports Server (NTRS)

    Pollock, David B.

    1998-01-01

    The Midcourse Space Experiment spacecraft, launched April 24, 1996, is expected to have a 5 year useful lifetime with a 12 month lifetime for the cryogenically cooled IR sensor. A pre-launch, ground based calibration of the instruments provided a basis for the pre-launch certification of the Level 2 data base these instruments produce. With the spacecraft in-orbit the certification of the instrument's Level 2 data base is being extended to the in-orbit environment.

  12. Momentum Transfer by Laser Ablation of Irregularly Shaped Space Debris

    SciTech Connect

    Liedahl, Duane A.; Libby, Stephen B.; Rubenchik, Alexander

    2010-10-08

    Proposals for ground-based laser remediation of space debris rely on the creation of appropriately directed ablation-driven impulses to either divert the fragment or drive it into an orbit with a perigee allowing atmospheric capture. For a spherical fragment, the ablation impulse is a function of the orbital parameters and the laser engagement angle. If, however, the target is irregularly shaped and arbitrarily oriented, new impulse effects come into play. Here we present an analysis of some of these effects.

  13. Primary propulsion of electrothermal, ion, and chemical systems for space-based radar orbit transfer

    NASA Technical Reports Server (NTRS)

    Wang, S.-Y.; Staiger, P. J.

    1985-01-01

    An orbit transfer mission concept has been studied for a Space-Based Radar (SBR) where 40 kW required for radar operation is assumed available for orbit transfer propulsion. Arcjet, pulsed electrothermal (PET), ion, and storable chemical systems are considered for the primary propulsion. Transferring two SBR per shuttle flight to 1112 km/60 deg using eiectrical propulsion systems offers an increased payload at the expense of increased trip time, up to 2000 kg each, which may be critical for survivability. Trade offs between payload mass, transfer time, launch site, inclination, and height of parking orbits are presented.

  14. Primary propulsion of electrothermal, ion and chemical systems for space-based radar orbit transfer

    NASA Technical Reports Server (NTRS)

    Wang, S. Y.; Staiger, P. J.

    1985-01-01

    An orbit transfer mission concept has been studied for a Space-Based Radar (SBR) where 40 kW required for radar operation is assumed available for orbit transfer propulsion. Arcjet, pulsed electrothermal (PET), ion, and storable chemical systems are considered for the primary propulsion. Transferring two SBR per shuttle flight to 1112 km/60 deg using electrical propulsion systems offers an increased payload at the expense of increased trip time, up to 2000 kg each, which may be critical for survivability. Trade offs between payload mass, transfer time, launch site, inclination, and height of parking orbits are presented.

  15. Millimeter-Wave Wireless Power Transfer Technology for Space Applications

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Goutam; Manohara, Harish; Mojarradi, Mohammad M.; Vo, Tuan A.; Mojarradi, Hadi; Bae, Sam Y.; Marzwell, Neville

    2008-01-01

    In this paper we present a new compact, scalable, and low cost technology for efficient receiving of power using RF waves at 94 GHz. This technology employs a highly innovative array of slot antennas that is integrated on substrate composed of gold (Au), silicon (Si), and silicon dioxide (SiO2) layers. The length of the slots and spacing between them are optimized for a highly efficient beam through a 3-D electromagnetic simulation process. Antenna simulation results shows a good beam profile with very low side lobe levels and better than 93% antenna efficiency.

  16. Heat transfer in space power and propulsion systems

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Simoneau, R. J.; Dunning, J. W., Jr.

    1986-01-01

    NASA's planned Space Station has projected power requirements in the 75-300 kW range; attention is presently given to the range of power system configurations thus far proposed. These are a silicon solar cell system incorporating regenerative fuel cell or battery storage, with a 10-year lifetime, a solar-dynamic power system with phase-change or regenerative fuel cell energy storage, and a combination of these two alternatives. A development status evaluation is also given for the propulsion systems that may be used by next-generation boosters. These include such novel airbreathing systems as turboramjets, air liquefaction cycle rockets, airturboramjet/rockets, and supersonic combustion ramjets.

  17. Generalized transfer matrix method for propagation of surface waves in layered azimuthally anisotropic half-space

    NASA Astrophysics Data System (ADS)

    Liu, Tianyun; Zhao, Chongbin; Duan, Yunling

    2012-08-01

    This paper presents a systematic and efficient method, namely the generalized transfer matrix method, for evaluating the dispersion curves and eigenfunctions of surface waves in multilayered azimuthally anisotropic half-space. Apart from avoiding the well-known numerical difficulties associated with the existing Thomson-Haskell method, the generalized transfer matrix method possesses the robust determination of independent polarization vectors by using the singular value decomposition (SVD) approach, the explicit inversion of the 6 × 6 eigencolumn matrix without any resort to numerical inversion and the efficient computation of eigenfunctions for layered azimuthally anisotropic media. By means of straightforward transformations, the generalized transfer matrix method leads to a twofold recursive algorithm: (1) for the recursive computation of phase velocities it starts from the bottom half-space to the top layer and (2) for the recursive solution of eigenfunctions it starts from the top layer to the bottom half-space. While keeping the simplicity of the Thomson-Haskell transfer matrix method, the generalized transfer matrix method is of unconditional stability and computational efficiency. The related numerical examples demonstrate that the generalized transfer matrix method is a powerful and robust tool for simulating the propagation of elastic surface waves in the layered azimuthally anisotropic half-space.

  18. Heat transfer measurements on biconics at incidence in hypersonic high enthalpy air and nitrogen flows

    NASA Technical Reports Server (NTRS)

    Gai, S. L.; Cain, T.; Joe, W. S.; Sandeman, R. J.; Miller, C. G.

    1988-01-01

    Heat transfer rate measurements have been obtained at 0, 5, 15, and 21 deg angles-of-attack for a straight biconic scale model of an aeroassisted orbital vehicle proposed for planetary probe missions. Heat-transfer distributions were measured using palladium thin-film resistance gauges deposited on a glass-ceramic substrate. The windward heat transfer correlations were based on equilibrium flow in the shock layer of the model, although the flow may depart from equilibrium in the flow-field.

  19. Heat transfer enhancement techniques for Space Station cold plates

    NASA Astrophysics Data System (ADS)

    Peterson, G. P.; Fletcher, L. S.

    1990-01-01

    Two attachment techniques for mounting electronic equipment to Space Station cold plates were analyzed and compared using thin foils of lead, tin, aluminum, and copper to enhance the thermal contact conductance. The two techniques evaluated included a 70 mm x 70 mm bolted attachment technique and an attachment scheme using an inflatable bladder. The results indicate that, even in the presence of the metallic foils, the bolted technique results in large variations in the local thermal contact conductance over the surface of the cold plate, while the pressurized bladder yields more uniform local contact conductance values. In addition, the results indicated that the lead foil provided an enhancement factor of approximately 3, the tin foil an enhancement factor of approximately 1.5, the aluminum an enhancement factor of approximately 1.0, and the copper an enhancement factor of approximately 0.9.

  20. Technology needs for lunar and Mars space transfer systems

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon R.; Cothran, Bradley C.; Donahue, Benjamin; Mcghee, Jerry

    1991-01-01

    The determination of appropriate space transportation technologies and operating modes is discussed with respect to both lunar and Mars missions. Three levels of activity are set forth to examine the sensitivity of transportation preferences including 'minimum,' 'full science,' and 'industrialization and settlement' categories. High-thrust-profile missions for lunar and Mars transportation are considered in terms of their relative advantages, and transportation options are defined in terms of propulsion and braking technologies. Costs and life-cycle cost estimates are prepared for the transportation preferences by using a parametric cost model, and a return-on-investment summary is given. Major technological needs for the programs are listed and include storable propulsion systems; cryogenic engines and fluids management; aerobraking; and nuclear thermal, nuclear electric, electric, and solar electric propulsion technologies.

  1. Dual-Use Space Technology Transfer Conference and Exhibition. Volume 2

    NASA Technical Reports Server (NTRS)

    Krishen, Kumar (Compiler)

    1994-01-01

    This is the second volume of papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools; systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development; perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; and robotics technologies.

  2. Dual-Use Space Technology Transfer Conference and Exhibition. Volume 1

    NASA Technical Reports Server (NTRS)

    Krishen, Kumar (Compiler)

    1994-01-01

    This document contains papers presented at the Dual-Use Space Technology Transfer Conference and Exhibition held at the Johnson Space Center February 1-3, 1994. Possible technology transfers covered during the conference were in the areas of information access; innovative microwave and optical applications; materials and structures; marketing and barriers; intelligent systems; human factors and habitation; communications and data systems; business process and technology transfer; software engineering; biotechnology and advanced bioinstrumentation; communications signal processing and analysis; new ways of doing business; medical care; applications derived from control center data systems; human performance evaluation; technology transfer methods; mathematics, modeling, and simulation; propulsion; software analysis and decision tools systems/processes in human support technology; networks, control centers, and distributed systems; power; rapid development perception and vision technologies; integrated vehicle health management; automation technologies; advanced avionics; ans robotics technologies. More than 77 papers, 20 presentations, and 20 exhibits covering various disciplines were presented b experts from NASA, universities, and industry.

  3. Technology Transfer and the Civil Space Program. Volume 2: Workshop proceedings

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The objectives were to (1) provide a top-level review of the Integrated Technology Plan (ITP) and current civil space technology plans, including planning processes and technologies; (2) discuss and assess technology transfer (TT) experiences across a wide range of participants; (3) identify alternate categories/strategies for TT and define the objectives of transfer processes in each case; (4) identify the roles of various government 'stakeholders', aerospace industry, industries at large, and universities in civil space technology research, development, demonstration, and transfer; (5) identify potential barriers and/or opportunities to successful civil space TT; (6) identify specific needs for innovations in policy, programs, and/or procedures to facilitate TT; and (7) develop a plan of attack for the development of a workshop report. Papers from the workshop are presented.

  4. Space transfer vehicle concepts and requirements, volume 2, book 1

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The objective of the systems engineering task was to develop and implement an approach that would generate the required study products as defined by program directives. This product list included a set of system and subsystem requirements, a complete set of optimized trade studies and analyses resulting in a recommended system configuration, and the definition of an integrated system/technology and advanced development growth path. A primary ingredient in the approach was the TQM philosophy stressing job quality from the inception. Included throughout the Systems Engineering, Programmatics, Concepts, Flight Design, and Technology sections are data supporting the original objectives as well as supplemental information resulting from program activities. The primary result of the analyses and studies was the recommendation of a single propulsion stage Lunar Transportation System (LTS) configuration that supports several different operations scenarios with minor element changes. This concept has the potential to support two additional scenarios with complex element changes. The space based LTS concept consists of three primary configurations--Piloted, Reusable Cargo, and Expendable Cargo.

  5. Vehicle for Space Transfer and Recovery (VSTAR), volume 2: Substantiating analyses and data

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The Vehicle Space Transfer and Recovery (VSTAR) system is designed as a manned orbital transfer vehicle (MOTV) with the primary mission of Satellite Launch and Repair (SLR). Reference materials, calculations and trade studies used in the analysis and selection of VSTAR components. Each major VSTAR system is examined separately. Simple graphs and tables are used to make qualitative comparisons of various VSTAR component candidates. Equations and/or calculations used for a particular analysis are also included where applicable.

  6. Ground-to-space optical power transfer. [using laser propulsion for orbit transfer

    NASA Technical Reports Server (NTRS)

    Mevers, G. E.; Hayes, C. L.; Soohoo, J. F.; Stubbs, R. M.

    1978-01-01

    Using laser radiation as the energy input to a rocket, it is possible to consider the transfer of large payloads economically between low initial orbits and higher energy orbits. In this paper we will discuss the results of an investigation to use a ground-based High Energy Laser (HEL) coupled to an adaptive antenna to transmit multi-megawatts of power to a satellite in low-earth orbit. Our investigation included diffraction effects, atmospheric transmission efficiency, adaptive compensation for atmospheric turbulence effects, including the servo bandwidth requirements for this correction, and the adaptive compensation for thermal blooming. For these evaluations we developed vertical profile models of atmospheric absorption, strength of optical turbulence (CN2), wind, temperature, and other parameters necessary to calculate system performance. Our atmospheric investigations were performed for CO2, 12C18O2 isotope, CO and DF wavelengths. For all of these considerations, output antenna locations of both sea level and mountain top (3.5 km above sea level) were used. Several adaptive system concepts were evaluated with a multiple source phased array concept being selected. This system uses an adaption technique of phase locking independent laser oscillators. When both system losses and atmospheric effects were assessed, the results predicted an overall power transfer efficiency of slightly greater than 50%.

  7. Unmanned, space-based, reusable orbital transfer vehicle, DARVES. Volume 1: Trade analysis and design

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The design of an unmanned, space-based, reusable Orbital Transfer Vehicle (OTV) is presented. This OTV will be utilized for the delivery and retrieval of satellites from geosynchronous Earth orbit (GEO) in conjunction with a space station assumed to be in existence in low Earth orbit (LEO). The trade analysis used to determine the vehicle design is presented, and from this study a vehicle definition is given.

  8. Minimum energy-loss guidance for aero-assisted orbital plane change

    NASA Technical Reports Server (NTRS)

    Hull, D. G.; Giltner, J. M.; Speyer, J. L.; Mapar, J.

    1984-01-01

    Minimum energy-loss guidance for the aero-assisted plane change of an orbiting vehicle is developed and applied to the plane change of a circular orbit. First, trajectories which minimize the fuel required to change the orbital plane are computed for a realistic vehicle. From these trajectories, it is observed that the fuel weight is minimized if the velocity at exit from the atmosphere is maximized. Next, for the atmospheric turn, approximate optimal controls (angle of attack and bank angle) which maximize the exit velocity are derived. Finally, the minimum-fuel problem is resolved using optimal guidance for the atmospheric part of the trajectory, and the optimization problem reduces to a one-dimensional parameter minimization. Successful plane changes up to 40 deg are demonstrated. Optimal guidance requires up to 14 percent more fuel than the 'true' optimum but only 50 percent of the fuel required by the single-impulse maneuver. Finally, the guidance law developed here is implementable because only algebraic manipulations are required.

  9. Review of a code development and calibration program in support of the aeroassist flight experiment

    NASA Technical Reports Server (NTRS)

    Gnoffo, Peter A.

    1989-01-01

    The code development and calibration program for the Langley Aerothermodynamic Upwind Relaxation Algorithm (LAURA) is reviewed, with emphasis directed toward support of the Aeroassist Flight Experiment (AFE). The flight project is designed to obtain data which will be used in the validation of computational fluid dynamic approximation methods. Comparisons between experimental data and numerical simulation focus on perfect-gas tests over a scale model of the AFE and on flight and ground tests which challenge some aspect of the thermochemical nonequilibrium model. In the first case, the gas model is simple, but the grid-related problems of defining the real vehicle are present. In the second case, the vehicle geometries are simple, but thermochemical processes must be modeled correctly in order to compare with the experimental data. These comparisons are described as calibration runs because they test elements of the numerical simulation, but no single data set adequately simulates the full-scale AFE flight conditions. Comparisons between computation and experiment over a broad range of data sets show generally good agreement, though some aspects of the numerical model require further development.

  10. Controlling the column spacing in isothermal magnetic advection to enable tunable heat and mass transfer

    NASA Astrophysics Data System (ADS)

    Solis, Kyle J.; Martin, James E.

    2012-11-01

    Isothermal magnetic advection (IMA) is a recently discovered method of inducing highly organized, non-contact flow lattices in suspensions of magnetic particles, using only uniform ac magnetic fields of modest strength. The initiation of these vigorous flows requires neither a thermal gradient nor a gravitational field, and so can be used to transfer heat and mass in circumstances where natural convection does not occur. These advection lattices are comprised of a square lattice of antiparallel flow columns. If the column spacing is sufficiently large compared to the column length and the flow rate within the columns is sufficiently large, then one would expect efficient transfer of both heat and mass. Otherwise, the flow lattice could act as a countercurrent heat exchanger and only mass will be efficiently transferred. Although this latter case might be useful for feeding a reaction front without extracting heat, it is likely that most interest will be focused on using IMA for heat transfer. In this paper, we explore the various experimental parameters of IMA to determine which of these can be used to control the column spacing. These parameters include the field frequency, strength, and phase relation between the two field components, the liquid viscosity, and particle volume fraction. We find that the column spacing can easily be tuned over a wide range to enable the careful control of heat and mass transfer.

  11. High-efficiency pump for space helium transfer. Final Technical Report

    SciTech Connect

    Hasenbein, R.; Izenson, M.G.; Swift, W.L.; Sixsmith, H.

    1991-12-01

    A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project also has application for liquid helium circulation in terrestrial facilities and for transfer of cryogenic rocket propellants in space.

  12. Space transfer concepts and analyses for exploration missions: Technical directive 10

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon R.

    1992-01-01

    The current technical effort is part of the third phase of a broad-scoped and systematic study of space transfer concepts for human lunar and Mars missions. The study addressed issues that were raised during the previous phases but specifically on launch vehicle size trades and MEV options.

  13. 33 CFR 127.105 - Layout and spacing of marine transfer area for LNG.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Layout and spacing of marine transfer area for LNG. 127.105 Section 127.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.105 Layout...

  14. 33 CFR 127.105 - Layout and spacing of marine transfer area for LNG.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Layout and spacing of marine transfer area for LNG. 127.105 Section 127.105 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... AND LIQUEFIED HAZARDOUS GAS Waterfront Facilities Handling Liquefied Natural Gas § 127.105 Layout...

  15. Design study of an integrated aerobraking orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Scott, C. D.; Roberts, B. B.; Nagy, K.; Taylor, P.; Gamble, J. D.; Ceremeli, C. J.; Knoll, K. R.; Li, C. P.; Reid, R. C.

    1985-01-01

    An aerobraking orbital transfer vehicle (AOTV) concept, which has an aerobrake structure that is integrated with the propulsion stage, is discussed. The concept vehicle is to be assembled in space and is space-based. The advantages of aeroassist over an all propulsive vehicle are discussed and it is shown that the vehicle considered is very competitive with inflatable and deployable concepts from mass and performance aspects. The aerobrake geometry is an ellipsoidally blunted, raked-off, elliptical wide-angle cone with a toroidal skirt. Propellant tanks, engines, and subsystems are integrated into a closed, isogrid aerobrake structure which provides rigidity. The vehicle has two side-firing, gimbaled RL-10 type engines and carries 38,000 kg of useable propellant. The trajectory during aerobraking is determined from an adaptive guidance logic, and the heating is determined from engineering correlations as well as 3-D Navier-Stokes solutions. The AOTV is capable of placing 13,500 kg payload into geosynchronous Earth orbit (GEO) or carrying a LEO-GEO-LEO round-trip payload of 7100 kg. A two-stage version considered for lunar missions results in a lunar surface delivery capability of 18,000 kg or a round-trip capability of 6800 kg with 3860 kg delivery-only capability.

  16. Electrical characterization of a Space Station Freedom alpha utility transfer assembly

    NASA Technical Reports Server (NTRS)

    Yenni, Edward J.

    1994-01-01

    Electrical power, command signals and data are transferred across the Space Station Freedom solar alpha rotary joint by roll rings, which are incorporated within the Utility Transfer Assembly (UTA) designed and manufactured by Honeywell Space Systems Operations. A developmental Model of the UTA was tested at the NASA Lewis Research Center using the Power Management and Distribution DC test bed. The objectives of these tests were to obtain data for calibrating system models and to support final design of qualification and flight units. This testing marked the first time the UTA was operated at high power levels and exposed to electrical conditions similar to that which it will encounter on the actual Space Station. Satisfactory UTA system performance was demonstrated within the scope of this testing.

  17. Plant Seeds as Model Vectors for the Transfer of Life Through Space

    NASA Astrophysics Data System (ADS)

    Tepfer, David; Leach, Sydney

    2006-12-01

    We consider plant seeds as terrestrial models for a vectored life form that could protect biological information in space. Seeds consist of maternal tissue surrounding and protecting an embryo. Some seeds resist deleterious conditions found in space: ultra low vacuum, extreme temperatures and radiation, including intense UV light. In a receptive environment, seeds could liberate a viable embryo, viable higher cells or a viable free-living organism (an endosymbiont or endophyte). Even if viability is lost, seeds still contain functional macro and small molecules (DNA, RNA, proteins, amino acids, lipids, etc.) that could provide the chemical basis for starting or modifying life. The possible release of endophytes or endosymbionts from a seed-like space traveler suggests that multiple domains of life, defined in DNA sequence phylogenies, could be disseminated simultaneously from Earth. We consider the possibility of exospermia, the outward transfer of life, as well as introspermia, the inward transfer of life-both as a contemporary and ancient events.

  18. Hypersonic shock tunnel heat transfer tests of the Space Shuttle SILTS pod configuration

    NASA Technical Reports Server (NTRS)

    Wittliff, C. E.

    1983-01-01

    Heat transfer measurements have been made on a 0.0175-scale NASA Space Shuttle orbiter model having a simulated SILTS (Shuttle Infrared Leeside Temperature Sensor) pod on top of the vertical tail. Heat transfer distributions were measured both on the pod and on the vertical tail. The test program covered Mach numbers of 8, 11 and 16 in air, at Reynolds numbers from 100,000 to 18 million, based on model length. The angle of attack ranged from 30 deg to 40 deg at sideslip angles from -2 to +2 deg. Data were obtained with 92 thin film assistance thermometers located on the SILTS pod and on the upper 30 percent of the vertical tail. Heat transfer rates measured on the vertical tail show good agreement with flight data obtained from missions STS-1, -2 and -3. The variation of heat transfer to the pod with Reynolds number, Mach number and angle of attack is discussed.

  19. Optimization of Return Trajectories for Orbital Transfer Vehicle between Earth and Moon

    NASA Technical Reports Server (NTRS)

    Funase, Ryu; Tsuda, Yuichi; Kawaguchi, Jun'ichiro

    2007-01-01

    In this paper, optimum trajectories in Earth Transfer Orbit (ETO) for a lunar transportation system are proposed. This paper aims at improving the payload ratio of the reusable orbital transfer vehicle (OTV), which transports the payload from Low Earth Orbit (LEO) to Lunar Low Orbit (LLO) and returns to LEO. In ETO, we discuss ballistic flight using chemical propulsion, multi-impulse flight using electrical propulsion, and aero-assisted flight using aero-brake. The feasibility of the OTV is considered.

  20. Evaluation of Deep Space Ka-Band Data Transfer using Radiometeorological Forecasts and Radiometer Measurements

    NASA Astrophysics Data System (ADS)

    Montopoli, Mario; Marzano, Frank S.; Biscarini, Marianna; Milani, Luca; Cimini, Domenico; De Sanctis, Klaide; Di Fabio, Saverio

    2016-04-01

    Deep space exploration is aimed at acquiring information about the solar system. In this scenario, telecommunications links between Earth ground receiving stations and extra-terrestrial satellite platforms have to be designed in order to ensure the optimal transfer of the acquired scientific data back to the Earth. A significant communication capacity has to be planned when very large distances, as those characterising deep space links, are involved thus fostering more ambitious scientific mission requirements. At the current state of the art, two microwave channel frequencies are used to perform the deep space data transfer: X band (~ 8.4 GHz) and Ka band (~ 32 GHz) channel. Ka-band transmission can offer an advantage over X-band in terms of antenna performance with the same antenna effective area and an available data transfer bandwidth (50 times higher at Ka band than X band). However, Earth troposphere-related impairments can affects the space-to-Earth carrier signals at frequencies higher than 10 GHz by degrading its integrity and thus reducing the deep space channel temporal availability. Such atmospheric impairments, especially in terms of path attenuation, their statistic and the possibility to forecast them in the next 24H at the Earth's receiving station would allow a more accurate design of the deep space link, promoting the mitigation of the detrimental effects on the link availability. To pursue this aim, meteorological forecast models and in situ measurements need to be considered in order to characterise the troposphere in terms of signal path attenuation at current and future time. In this work, we want to show how the synergistic use of meteorological forecasts, radiative transfer simulations and in situ measurements such as microwave radiometry observations, rain gauges and radiosoundings, can aid the optimisation of a deep space link at Ka band and improve its performance with respect to usual practices. The outcomes of the study are in the

  1. Time and Space Resolved Heat Transfer Measurements Under Nucleate Bubbles with Constant Heat Flux Boundary Conditions

    NASA Technical Reports Server (NTRS)

    Myers, Jerry G.; Hussey, Sam W.; Yee, Glenda F.; Kim, Jungho

    2003-01-01

    Investigations into single bubble pool boiling phenomena are often complicated by the difficulties in obtaining time and space resolved information in the bubble region. This usually occurs because the heaters and diagnostics used to measure heat transfer data are often on the order of, or larger than, the bubble characteristic length or region of influence. This has contributed to the development of many different and sometimes contradictory models of pool boiling phenomena and dominant heat transfer mechanisms. Recent investigations by Yaddanapyddi and Kim and Demiray and Kim have obtained time and space resolved heat transfer information at the bubble/heater interface under constant temperature conditions using a novel micro-heater array (10x10 array, each heater 100 microns on a side) that is semi-transparent and doubles as a measurement sensor. By using active feedback to maintain a state of constant temperature at the heater surface, they showed that the area of influence of bubbles generated in FC-72 was much smaller than predicted by standard models and that micro-conduction/micro-convection due to re-wetting dominated heat transfer effects. This study seeks to expand on the previous work by making time and space resolved measurements under bubbles nucleating on a micro-heater array operated under constant heat flux conditions. In the planned investigation, wall temperature measurements made under a single bubble nucleation site will be synchronized with high-speed video to allow analysis of the bubble energy removal from the wall.

  2. Effects of Pin Detached Space on Heat Transfer and Pin-Fin Arrays

    SciTech Connect

    Siw, Sin C.; Chyu, Minking K.; Shih, Tom I-P.; Alvin, Mary Anne

    2012-08-01

    Heat transfer and pressure characteristics in a rectangular channel with pin-fin arrays of partial detachment from one of the endwalls have been experimentally studied. The overall channel geometry (W = 76.2 mm, E = 25.4 mm) simulates an internal cooling passage of wide aspect ratio (3:1) in a gas turbine airfoil. With a given pin diameter, D = 6.35 mm = ¼E, three different pin-fin height-to-diameter ratios, H/D = 4, 3, and 2, were examined. Each of these three cases corresponds to a specific pin array geometry of detachment spacing (C) between the pin tip and one of the endwalls, i.e., C/D = 0, 1, 2, respectively. The Reynolds number, based on the hydraulic diameter of the unobstructed cross-section and the mean bulk velocity, ranges from 10,000 to 25,000. The experiment employs a hybrid technique based on transient liquid crystal imaging to obtain the distributions of the local heat transfer coefficient over all of the participating surfaces, including the endwalls and all the pin elements. Experimental results reveal that the presence of a detached space between the pin tip and the endwall has a significant effect on the convective heat transfer and pressure loss in the channel. The presence of pin-to-endwall spacing promotes wall-flow interaction, generates additional separated shear layers, and augments turbulent transport. In general, an increase in detached spacing, or C/D, leads to lower heat transfer enhancement and pressure drop. However, C/D = 1, i.e., H/D = 3, of a staggered array configuration exhibits the highest heat transfer enhancement, followed by the cases of C/D = 0 and C/D = 2, i.e., H/D = 4 or 2, respectively.

  3. Definition of technology development missions for early space stations orbit transfer vehicle serving. Phase 2, task 1: Space station support of operational OTV servicing

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Representative space based orbital transfer vehicles (OTV), ground based vehicle turnaround assessment, functional operational requirements and facilities, mission turnaround operations, a comparison of ground based versus space based tasks, activation of servicing facilities prior to IOC, fleet operations requirements, maintenance facilities, OTV servicing facilities, space station support requirements, and packaging for delivery are discussed.

  4. In-space experiment on thermoacoustic convection heat transfer phenomenon-experiment definition

    NASA Technical Reports Server (NTRS)

    Parang, M.; Crocker, D. S.

    1991-01-01

    The definition phase of an in-space experiment in thermoacoustic convection (TAC) heat transfer phenomenon is completed and the results are presented and discussed in some detail. Background information, application and potential importance of TAC in heat transfer processes are discussed with particular focus on application in cryogenic fluid handling and storage in microgravity space environment. Also included are the discussion on TAC space experiment objectives, results of ground support experiments, hardware information, and technical specifications and drawings. The future plans and a schedule for the development of experiment hardware (Phase 1) and flight tests and post-flight analysis (Phase 3/4) are also presented. The specific experimental objectives are rapid heating of a compressible fluid and the measurement of the fluid temperature and pressure and the recording and analysis of the experimental data for the establishment of the importance of TAC heat transfer process. The ground experiments that were completed in support of the experiment definition included fluid temperature measurement by a modified shadowgraph method, surface temperature measurements by thermocouples, and fluid pressure measurements by strain-gage pressure transducers. These experiments verified the feasibility of the TAC in-space experiment, established the relevance and accuracy of the experimental results, and specified the nature of the analysis which will be carried out in the post-flight phase of the report.

  5. Benefits of high aerodynamic efficiency to orbital transfer vehicles

    NASA Technical Reports Server (NTRS)

    Andrews, D. G.; Norris, R. B.; Paris, S. W.

    1984-01-01

    The benefits and costs of high aerodynamic efficiency on aeroassisted orbital transfer vehicles (AOTV) are analyzed. Results show that a high lift to drag (L/D) AOTV can achieve significant velocity savings relative to low L/D aerobraked OTV's when traveling round trip between low Earth orbits (LEO) and alternate orbits as high as geosynchronous Earth orbit (GEO). Trajectory analysis is used to show the impact of thermal protection system technology and the importance of lift loading coefficient on vehicle performance. The possible improvements in AOTV subsystem technologies are assessed and their impact on vehicle inert weight and performance noted. Finally, the performance of high L/D AOTV concepts is compared with the performances of low L/D aeroassisted and all propulsive OTV concepts to assess the benefits of aerodynamic efficiency on this class of vehicle.

  6. High Precision Time Transfer in Space with a Hydrogen Maser on MIR

    NASA Technical Reports Server (NTRS)

    Mattison, Edward M.; Vessot, Robert F. C.

    1996-01-01

    An atomic hydrogen maser clock system designed for long term operation in space will be installed on the Russian space station Mir, in late 1997. The H-maser's frequency stability will be measured using pulsed laser time transfer techniques. Daily time comparisons made with a precision of better than 100 picoseconds will allow an assessment of the long term stability of the space maser at a level on the order of 1 part in 10(sup 15) or better. Laser pulse arrival times at the spacecraft will be recorded with a resolution of 10 picoseconds relative to the space clock's time scale. Cube corner reflectors will reflect the pulses back to the Earth laser station to determine the propagation delay and enable comparison with the Earth-based time scale. Data for relativistic and gravitational frequency corrections will be obtained from a Global Positioning System (GPS) receiver.

  7. Cryogenic Propellant Storage and Transfer Technology Demonstration For Long Duration In-Space Missions

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.; Motil, Susan M.; Kortes, Trudy F.; Taylor, William J.; McRight, Patrick S.

    2012-01-01

    The high specific impulse of cryogenic propellants can provide a significant performance advantage for in-space transfer vehicles. The upper stages of the Saturn V and various commercial expendable launch vehicles have used liquid oxygen and liquid hydrogen propellants; however, the application of cryogenic propellants has been limited to relatively short duration missions due to the propensity of cryogens to absorb environmental heat resulting in fluid losses. Utilizing advanced cryogenic propellant technologies can enable the efficient use of high performance propellants for long duration missions. Crewed mission architectures for beyond low Earth orbit exploration can significantly benefit from this capability by developing realistic launch spacing for multiple launch missions, by prepositioning stages and by staging propellants at an in-space depot. The National Aeronautics and Space Administration through the Office of the Chief Technologist is formulating a Cryogenic Propellant Storage and Transfer Technology Demonstration Mission to mitigate the technical and programmatic risks of infusing these advanced technologies into the development of future cryogenic propellant stages or in-space propellant depots. NASA is seeking an innovative path for human space exploration, which strengthens the capability to extend human and robotic presence throughout the solar system. This mission will test and validate key cryogenic technological capabilities and has the objectives of demonstrating advanced thermal control technologies to minimize propellant loss during loiter, demonstrating robust operation in a microgravity environment, and demonstrating efficient propellant transfer on orbit. The status of the demonstration mission concept development, technology demonstration planning and technology maturation activities in preparation for flight system development are described.

  8. Laser Time-Transfer and Space-Time Reference in Orbit

    NASA Astrophysics Data System (ADS)

    Berceau, P.; Hollberg, L.

    2014-01-01

    A high performance Space-Time Reference in orbit could be realized using a stable atomic clock in a precisely defined orbit and linking that to high accuracy atomic clocks on the ground using a laser based time-transfer link. This would enhance performance of existing systems and provide unique capabilities in navigation, precise timing, earth sciences, geodesy and the same approach could provide a platform for testing fundamental physics in space. Precise laser timeand frequency-transfer from the ground to an orbiting satellite would make it possible to improve upon the current state of the art in timing (about 1 to 30 ns achieved with GPS) by roughly a factor of 1000 to the 1 ps level.

  9. Space transfer vehicle concepts and requirements study. Volume 2, book 3: STV system interfaces

    NASA Technical Reports Server (NTRS)

    Weber, Gary A.

    1991-01-01

    This report presents the results of systems analyses and conceptual design of space transfer vehicles (STV). The missions examined included piloted and unpiloted lunar outpost support and spacecraft servicing, and unpiloted payload delivery to various earth and solar orbits. The study goal was to examine the mission requirements and provide a decision data base for future programmatic development plans. The final lunar transfer vehicles provided a wide range of capabilities and interface requirements while maintaining a constant payload mission model. Launch vehicle and space station sensitivity was examined, with the final vehicles as point design covering the range of possible options. Development programs were defined and technology readiness levels for different options were determined. Volume 1 presents the executive summary, volume 2 provides the study results, and volume 3 the cost and WBS data.

  10. Capillary-Driven Heat Transfer Experiment: Keeping It Cool in Space

    NASA Technical Reports Server (NTRS)

    Lekan, Jack F.; Allen, Jeffrey S.

    1998-01-01

    Capillary-pumped loops (CPL's) are devices that are used to transport heat from one location to another--specifically to transfer heat away from something. In low-gravity applications, such as satellites (and possibly the International Space Station), CPL's are used to transfer heat from electrical devices to space radiators. This is accomplished by evaporating one liquid surface on the hot side of the CPL and condensing the vapor produced onto another liquid surface on the cold side. Capillary action, the phenomenon that causes paper towels to absorb spilled liquids, is used to "pump" the liquid back to the evaporating liquid surface (hot side) to complete the "loop." CPL's require no power to operate and can transfer heat over distances as large as 30 ft or more. Their reliance upon evaporation and condensation to transfer heat makes them much more economical in terms of weight than conventional heat transfer systems. Unfortunately, they have proven to be unreliable in space operations, and the explanation for this unreliability has been elusive. The Capillary-Driven Heat Transfer (CHT) experiment is investigating the fundamental fluid physics phenomena thought to be responsible for the failure of CPL's in low-gravity operations. If the failure mechanism can be identified, then appropriate design modifications can be developed to make capillary phase-change heat-transport devices a more viable option in space applications. CHT was conducted onboard the Space Shuttle Columbia during the first Microgravity Science Laboratory (MSL-1) mission, STS-94, which flew from July 1 to 17, 1997. The CHT glovebox investigation, which was conceived by Dr. Kevin Hallinan and Jeffrey Allen of the University of Dayton, focused on studying the dynamics associated with the heating and cooling at the evaporating meniscus within a capillary phase-change device in a low-gravity environment. The CHT experimental hardware was designed by a small team of engineers from Aerospace Design

  11. The Physics of Imaging with Remote Sensors : Photon State Space & Radiative Transfer

    NASA Technical Reports Server (NTRS)

    Davis, Anthony B.

    2012-01-01

    Standard (mono-pixel/steady-source) retrieval methodology is reaching its fundamental limit with access to multi-angle/multi-spectral photo- polarimetry. Next... Two emerging new classes of retrieval algorithm worth nurturing: multi-pixel time-domain Wave-radiometry transition regimes, and more... Cross-fertilization with bio-medical imaging. Physics-based remote sensing: - What is "photon state space?" - What is "radiative transfer?" - Is "the end" in sight? Two wide-open frontiers! center dot Examples (with variations.

  12. Development of a rotary fluid transfer coupling and support mechanism for space station

    NASA Technical Reports Server (NTRS)

    Bradley, O. H., Jr.; Costulis, J. A.; Porter, A. H.

    1988-01-01

    A design was developed for a rotary fluid coupling to transfer coolant fluids (primarily anhydrous ammonia) across rotating joints of the space station. Development testing using three conceptual designs yielded data which were used to establish the design of a multipass fluid coupling capable of handling three fluid circuits. In addition, a mechanism to support the fluid coupling and allow an astronaut to replace the coupling quickly and easily was designed.

  13. A Piezoelectric Unimorph Deformable Mirror Concept by Wafer Transfer for Ultra Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Yang, Eui-Hyeok; Shcheglov, Kirill

    2002-01-01

    Future concepts of ultra large space telescopes include segmented silicon mirrors and inflatable polymer mirrors. Primary mirrors for these systems cannot meet optical surface figure requirements and are likely to generate over several microns of wavefront errors. In order to correct for these large wavefront errors, high stroke optical quality deformable mirrors are required. JPL has recently developed a new technology for transferring an entire wafer-level mirror membrane from one substrate to another. A thin membrane, 100 mm in diameter, has been successfully transferred without using adhesives or polymers. The measured peak-to-valley surface error of a transferred and patterned membrane (1 mm x 1 mm x 0.016 mm) is only 9 nm. The mirror element actuation principle is based on a piezoelectric unimorph. A voltage applied to the piezoelectric layer induces stress in the longitudinal direction causing the film to deform and pull on the mirror connected to it. The advantage of this approach is that the small longitudinal strains obtainable from a piezoelectric material at modest voltages are thus translated into large vertical displacements. Modeling is performed for a unimorph membrane consisting of clamped rectangular membrane with a PZT layer with variable dimensions. The membrane transfer technology is combined with the piezoelectric bimorph actuator concept to constitute a compact deformable mirror device with a large stroke actuation of a continuous mirror membrane, resulting in a compact A0 systems for use in ultra large space telescopes.

  14. Heat Transfer and Fluid Dynamics Measurements in the Expansion Space of a Stirling Cycle Engine

    NASA Technical Reports Server (NTRS)

    Jiang, Nan; Simon, Terrence W.

    2006-01-01

    The heater (or acceptor) of a Stirling engine, where most of the thermal energy is accepted into the engine by heat transfer, is the hottest part of the engine. Almost as hot is the adjacent expansion space of the engine. In the expansion space, the flow is oscillatory, impinging on a two-dimensional concavely-curved surface. Knowing the heat transfer on the inside surface of the engine head is critical to the engine design for efficiency and reliability. However, the flow in this region is not well understood and support is required to develop the CFD codes needed to design modern Stirling engines of high efficiency and power output. The present project is to experimentally investigate the flow and heat transfer in the heater head region. Flow fields and heat transfer coefficients are measured to characterize the oscillatory flow as well as to supply experimental validation for the CFD Stirling engine design codes. Presented also is a discussion of how these results might be used for heater head and acceptor region design calculations.

  15. Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles

    NASA Astrophysics Data System (ADS)

    Batra, T.; Schaltz, E.

    2015-05-01

    Magnetic fields emitted by wireless power transfer systems are of high importance with respect to human safety and health. Aluminum and ferrite are used in the system to reduce the fields and are termed as passive shielding. In this paper, the influence of these materials on the space profile has been investigated with the help of simulations on Comsol for the four possible geometries—no shielding, ferrite, aluminum, and full shielding. As the reflected impedance varies for the four geometries, the primary current is varied accordingly to maintain constant power transfer to the secondary side. Surrounding magnetic field plots in the vertical direction show that maxima's of the two coils for the no shielding geometry are centered at the respective coils and for the remaining three are displaced closer to each other. This closeness would lead to more effective addition of the two coil fields and an increase in the resultant field from space point of view. This closeness varies with distance in the horizontal direction and vertical gap between the coils and is explained in the paper. This paper provides a better understanding of effect of the passive shielding materials on the space nature of magnetic fields for wireless power transfer for vehicle applications.

  16. Linear perturbation theory of reionization in position space: Cosmological radiative transfer along the light cone

    NASA Astrophysics Data System (ADS)

    Mao, Yi; D'Aloisio, Anson; Wandelt, Benjamin D.; Zhang, Jun; Shapiro, Paul R.

    2015-04-01

    The linear perturbation theory of inhomogeneous reionization (LPTR) has been developed as an analytical tool for predicting the global ionized fraction and large-scale power spectrum of ionized density fluctuations during reionization. In the original formulation of the LPTR, the ionization balance and radiative transfer equations are linearized and solved in Fourier space. However, the LPTR's approximation to the full solution of the radiative transfer equation is not straightforward to interpret, since the latter is most intuitively conceptualized in position space. To bridge the gap between the LPTR and the language of numerical radiative transfer, we present a new, equivalent, position-space formulation of the LPTR that clarifies the approximations it makes and facilitates its interpretation. We offer a comparison between the LPTR and the excursion-set model of reionization (ESMR), and demonstrate the built-in capability of the LPTR to explore a wide range of reionization scenarios, and to go beyond the ESMR in exploring scenarios involving X-rays.

  17. Passive shielding effect on space profile of magnetic field emissions for wireless power transfer to vehicles

    SciTech Connect

    Batra, T. Schaltz, E.

    2015-05-07

    Magnetic fields emitted by wireless power transfer systems are of high importance with respect to human safety and health. Aluminum and ferrite are used in the system to reduce the fields and are termed as passive shielding. In this paper, the influence of these materials on the space profile has been investigated with the help of simulations on Comsol for the four possible geometries—no shielding, ferrite, aluminum, and full shielding. As the reflected impedance varies for the four geometries, the primary current is varied accordingly to maintain constant power transfer to the secondary side. Surrounding magnetic field plots in the vertical direction show that maxima's of the two coils for the no shielding geometry are centered at the respective coils and for the remaining three are displaced closer to each other. This closeness would lead to more effective addition of the two coil fields and an increase in the resultant field from space point of view. This closeness varies with distance in the horizontal direction and vertical gap between the coils and is explained in the paper. This paper provides a better understanding of effect of the passive shielding materials on the space nature of magnetic fields for wireless power transfer for vehicle applications.

  18. Operationally efficient propulsion system study (OEPSS) data book. Volume 6; Space Transfer Propulsion Operational Efficiency Study Task of OEPSS

    NASA Technical Reports Server (NTRS)

    Harmon, Timothy J.

    1992-01-01

    This document is the final report for the Space Transfer Propulsion Operational Efficiency Study Task of the Operationally Efficient Propulsion System Study (OEPSS) conducted by the Rocketdyne Division of Rockwell International. This Study task studied, evaluated and identified design concepts and technologies which minimized launch and in-space operations and optimized in-space vehicle propulsion system operability.

  19. Convective Heat Transfer in the Reusable Solid Rocket Motor of the Space Transportation System

    NASA Technical Reports Server (NTRS)

    Ahmad, Rashid A.; Cash, Stephen F. (Technical Monitor)

    2002-01-01

    This simulation involved a two-dimensional axisymmetric model of a full motor initial grain of the Reusable Solid Rocket Motor (RSRM) of the Space Transportation System (STS). It was conducted with CFD (computational fluid dynamics) commercial code FLUENT. This analysis was performed to: a) maintain continuity with most related previous analyses, b) serve as a non-vectored baseline for any three-dimensional vectored nozzles, c) provide a relatively simple application and checkout for various CFD solution schemes, grid sensitivity studies, turbulence modeling and heat transfer, and d) calculate nozzle convective heat transfer coefficients. The accuracy of the present results and the selection of the numerical schemes and turbulence models were based on matching the rocket ballistic predictions of mass flow rate, head end pressure, vacuum thrust and specific impulse, and measured chamber pressure drop. Matching these ballistic predictions was found to be good. This study was limited to convective heat transfer and the results compared favorably with existing theory. On the other hand, qualitative comparison with backed-out data of the ratio of the convective heat transfer coefficient to the specific heat at constant pressure was made in a relative manner. This backed-out data was devised to match nozzle erosion that was a result of heat transfer (convective, radiative and conductive), chemical (transpirating), and mechanical (shear and particle impingement forces) effects combined.

  20. Files in Space: Management & Transfer Applications and Operations: On-Board Segment & Communications

    NASA Astrophysics Data System (ADS)

    Dellandrea, Brice; De-Ferluc, Regid; Fourtier, Philippe; Soumagne, Raymond

    2013-08-01

    File structures are increasingly used on space missions both for payload science/observation data storage and for platform telecommands and housekeeping telemetries. On current missions, these file structures are specifically designed on a case-by-case basis with adapted communication protocols for Board/Ground file transfer and handling. Two studies on that field have been undergone by Thales Alenia Space for CNES on the last two years: a study in 2011/2012 on the file transfer systems (state of the art, trade-off and prototyping), and a second in 2012/2013 on the file management systems (specification and prototyping). The second study is still on-going, aiming at designing a generic file management system to suite general file implementations, compatible with the current file transfer protocols and covering the current and anticipated needs. This presentation provides some of the results of these studies and highlights the impact of file operations on board/ground communication sessions and on-board avionics & flight software.

  1. Note: Space qualified photon counting detector for laser time transfer with picosecond precision and stability

    NASA Astrophysics Data System (ADS)

    Prochazka, Ivan; Kodet, Jan; Blazej, Josef

    2016-05-01

    The laser time transfer link is under construction for the European Space Agency in the frame of Atomic Clock Ensemble in Space. We have developed and tested the flying unit of the photon counting detector optimized for this space mission. The results are summarized in this Note. An extreme challenge was to build a detector package, which is rugged, small and which provides long term detection delay stability on picosecond level. The device passed successfully all the tests required for space missions on the low Earth orbits. The detector is extremely rugged and compact. Its long term detection delay stability is excellent, it is better than ±1 ps/day, in a sense of time deviation it is better than 0.5 ps for averaging times of 2000 s to several hours. The device is capable to operate in a temperature range of -55 °C up to +60 °C, the change of the detection delay with temperature is +0.5 ps/K. The device is ready for integration into the space structure now.

  2. Note: Space qualified photon counting detector for laser time transfer with picosecond precision and stability.

    PubMed

    Prochazka, Ivan; Kodet, Jan; Blazej, Josef

    2016-05-01

    The laser time transfer link is under construction for the European Space Agency in the frame of Atomic Clock Ensemble in Space. We have developed and tested the flying unit of the photon counting detector optimized for this space mission. The results are summarized in this Note. An extreme challenge was to build a detector package, which is rugged, small and which provides long term detection delay stability on picosecond level. The device passed successfully all the tests required for space missions on the low Earth orbits. The detector is extremely rugged and compact. Its long term detection delay stability is excellent, it is better than ±1 ps/day, in a sense of time deviation it is better than 0.5 ps for averaging times of 2000 s to several hours. The device is capable to operate in a temperature range of -55 °C up to +60 °C, the change of the detection delay with temperature is +0.5 ps/K. The device is ready for integration into the space structure now. PMID:27250477

  3. Transferring of speech movements from video to 3D face space.

    PubMed

    Pei, Yuru; Zha, Hongbin

    2007-01-01

    We present a novel method for transferring speech animation recorded in low quality videos to high resolution 3D face models. The basic idea is to synthesize the animated faces by an interpolation based on a small set of 3D key face shapes which span a 3D face space. The 3D key shapes are extracted by an unsupervised learning process in 2D video space to form a set of 2D visemes which are then mapped to the 3D face space. The learning process consists of two main phases: 1) Isomap-based nonlinear dimensionality reduction to embed the video speech movements into a low-dimensional manifold and 2) K-means clustering in the low-dimensional space to extract 2D key viseme frames. Our main contribution is that we use the Isomap-based learning method to extract intrinsic geometry of the speech video space and thus to make it possible to define the 3D key viseme shapes. To do so, we need only to capture a limited number of 3D key face models by using a general 3D scanner. Moreover, we also develop a skull movement recovery method based on simple anatomical structures to enhance 3D realism in local mouth movements. Experimental results show that our method can achieve realistic 3D animation effects with a small number of 3D key face models. PMID:17093336

  4. A model of head-related transfer functions based on a state-space analysis

    NASA Astrophysics Data System (ADS)

    Adams, Norman Herkamp

    This dissertation develops and validates a novel state-space method for binaural auditory display. Binaural displays seek to immerse a listener in a 3D virtual auditory scene with a pair of headphones. The challenge for any binaural display is to compute the two signals to supply to the headphones. The present work considers a general framework capable of synthesizing a wide variety of auditory scenes. The framework models collections of head-related transfer functions (HRTFs) simultaneously. This framework improves the flexibility of contemporary displays, but it also compounds the steep computational cost of the display. The cost is reduced dramatically by formulating the collection of HRTFs in the state-space and employing order-reduction techniques to design efficient approximants. Order-reduction techniques based on the Hankel-operator are found to yield accurate low-cost approximants. However, the inter-aural time difference (ITD) of the HRTFs degrades the time-domain response of the approximants. Fortunately, this problem can be circumvented by employing a state-space architecture that allows the ITD to be modeled outside of the state-space. Accordingly, three state-space architectures are considered. Overall, a multiple-input, single-output (MISO) architecture yields the best compromise between performance and flexibility. The state-space approximants are evaluated both empirically and psychoacoustically. An array of truncated FIR filters is used as a pragmatic reference system for comparison. For a fixed cost bound, the state-space systems yield lower approximation error than FIR arrays for D>10, where D is the number of directions in the HRTF collection. A series of headphone listening tests are also performed to validate the state-space approach, and to estimate the minimum order N of indiscriminable approximants. For D = 50, the state-space systems yield order thresholds less than half those of the FIR arrays. Depending upon the stimulus uncertainty, a

  5. Space transfer vehicle concepts and requirements study. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Weber, Gary A.

    1991-01-01

    A description of the study in terms of background, objectives, and issues is provided. NASA is currently studying new initiatives of space exploration involving both piloted and unpiloted missions to destinations throughout the solar system. Many of these missions require substantial improvements in launch vehicle and upper stage capabilities. This study provides a focused examination of the Space Transfer Vehicles (STV) required to perform these missions using the emerging national launch vehicle definition, the Space Station Freedom (SSF) definition, and the latest mission scenario requirements. The study objectives are to define preferred STV concepts capable of accommodating future exploration missions in a cost-effective manner, determine the technology development (if any) required to perform these missions, and develop a decision database of various programmatic approaches for the development of the STV family of vehicles. Special emphasis was given to examining space basing (stationing reusable vehicles at a space station), examining the piloted lunar mission as a primary design mission, and restricting trade studies to the high-performance, near-term cryogenics (LO2/LH2) as vehicle propellant. The study progressed through three distinct 6-month phases. The first phase concentrated on supporting a NASA 3 month definition of exploration requirements (the '90-day study') and during this phase developed and optimized the space-based point-of-departure (POD) 2.5-stage lunar vehicle. The second phase developed a broad decision database of 95 different vehicle options and transportation architectures. The final phase chose the three most cost-effective architectures and developed point designs to carry to the end of the study. These reference vehicle designs are mutually exclusive and correspond to different national choices about launch vehicles and in-space reusability. There is, however, potential for evolution between concepts.

  6. Heat flux and shock shape measurements on an Aeroassist Flight Experiment model in a high enthalpy free piston shock tunnel

    NASA Technical Reports Server (NTRS)

    Gai, S. L.; Mudford, N. R.; Hackett, C.

    1992-01-01

    This paper describes measurements of heat flux and shock shapes made on a 2.08 percent scale model of the proposed Aeroassist Flight Experiment model in a high enthalpy free piston shock tunnel T3 at the Australian National University in Canberra, Australia. The enthalpy and Reynolds number range covered were 7.5 MJ/kg to 20 MJ/kg and 150,000 to 270,000 per meter respectively. The test Mach number varied between 7.5 and 8. Two test gases, air and nitrogen, were used and the model angle of attack varied from -10 deg to +10 deg to the free stream. The results are discussed and compared to the Mach 10 cold hypersonic air data as obtained in the Langley 31 inch Mach 10 Facility as well as the perfect gas CFD calculations of NASA LaRC.

  7. Conjugating binary systems for spacecraft thermal control. Appendix C: Aeroassist Flight Experiment Carrier Vehicle preliminary stress analysis

    NASA Technical Reports Server (NTRS)

    Ingram, J. E.; Murray, T. O.

    1989-01-01

    An assessment of the static strength of the Aeroassist Flight Experiment (AFE) Carrier Vehicle is presented. The Carrier Vehicle is the structural component which provides the mounting platform for the experiments, on-board computers, batteries, and other black boxes. In addition, the Solid Rocket Motor (SRM), the Thrusters, and the Aerobrake are all attached directly to the Carrier Vehicle. The basic approach in this analysis was to develop a NASTRAN Finite Element Model as a parallel effort to the preliminary design, and to use the internal loads from this model to perform the stress analysis. The NASTRAN method of Inertial Relief was employed. This method involves either specifying a set of CG (center of gravity) accelerations or applying forces at the CG and representing the Carrier Vehicle and all its mounted devices with the proper stiffness and mass properties.

  8. Propellantless Propulsion Technologies for In-Space Transportation

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Cook, Stephen (Technical Monitor)

    2001-01-01

    In order to implement the ambitious science and exploration missions planned over the next several decades, improvements in in-space transportation and propulsion technologies must be achieved. For robotic exploration and science missions, increased efficiencies of future propulsion systems are critical to reduce overall life-cycle costs. Future missions will require 2 to 3 times more total change in velocity over their mission lives than the NASA Solar Electric Technology Application Readiness (NSTAR) demonstration on the Deep Space 1 mission. Rendezvous and return missions will require similar investments in in-space propulsion systems. New opportunities to explore beyond the outer planets and to the stars will require unparalleled technology advancement and innovation. The Advanced Space Transportation Program (ASTP) is investing in technologies to achieve a factor of 10 reduction in the cost of Earth orbital transportation and a factor of 2 or 3 reduction in propulsion system mass and travel time for planetary missions within the next 15 years. Since more than 70% of projected launches over the next 10 years will require propulsion systems capable of attaining destinations beyond Low Earth Orbit, investment in in-space technologies will benefit a large percentage of future missions. Some of the most promising technologies for achieving these goals use the environment of space itself for energy and propulsion and are generically called, "propellantless" because they do not require on-board fuel to achieve thrust. An overview of the state-of-the-art in propellantless propulsion technologies such as solar and plasma sails, electrodynamic and momentum transfer tethers, and aeroassist and aerocapture will be described. Results of recent earth-based technology demonstrations and space tests will also be discussed.

  9. Tunable Real Space Transfer Oscillator by Delayed Feedback Control of Chaos

    NASA Astrophysics Data System (ADS)

    Cooper, D. P.; Schöll, E.

    1995-03-01

    It is demonstrated numerically that by using Pyragas' method of chaos self-control a stable semiconductor oscillator can be designed based on driven real-space transfer oscillations in a modulation-doped heterostructure. By application of a small time-continuous delayed feedback voltage control signal, different unstable periodic orbits embedded in the chaotic attractor can be stabilized. Thus different modes of self-generated periodic voltage oscillations can be selected by choosing an appropriate delay time. This provides tunability to different discrete frequencies.

  10. Finite-element reentry heat-transfer analysis of space shuttle Orbiter

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Quinn, Robert D.; Gong, Leslie

    1986-01-01

    A structural performance and resizing (SPAR) finite-element thermal analysis computer program was used in the heat-transfer analysis of the space shuttle orbiter subjected to reentry aerodynamic heating. Three wing cross sections and one midfuselage cross section were selected for the thermal analysis. The predicted thermal protection system temperatures were found to agree well with flight-measured temperatures. The calculated aluminum structural temperatures also agreed reasonably well with the flight data from reentry to touchdown. The effects of internal radiation and of internal convection were found to be significant. The SPAR finite-element solutions agreed reasonably well with those obtained from the conventional finite-difference method.

  11. Space transfer vehicle concepts and requirements. Volume 3: Program cost estimates

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The Space Transfer Vehicle (STV) Concepts and Requirements Study has been an eighteen-month study effort to develop and analyze concepts for a family of vehicles to evolve from an initial STV system into a Lunar Transportation System (LTS) for use with the Heavy Lift Launch Vehicle (HLLV). The study defined vehicle configurations, facility concepts, and ground and flight operations concepts. This volume reports the program cost estimates results for this portion of the study. The STV Reference Concept described within this document provides a complete LTS system that performs both cargo and piloted Lunar missions.

  12. Definition of technology development missions for early space station, orbit transfer vehicle servicing. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Orbital Transfer Vehicle (OTV) servicing study scope, propellant transfer, storage and reliquefaction technology development missions (TDM), docking and berthing TDM, maintenance TDM, OTV/payload integration TDM, combined TDMS design, summary space station accomodations, programmatic analysis, and TDM equipment operational usage are discussed.

  13. Heating of foods in space-vehicle environments. [by conductive heat transfer

    NASA Technical Reports Server (NTRS)

    Bannerot, R. B.; Cox, J. E.; Chen, C. K.; Heidelbaugh, N. D.

    1973-01-01

    In extended space missions, foods will be heated to enhance the psychological as well as the physiological well-being of the crew. In the low-gravity space environment natural convection is essentially absent so that the heat transfer within the food is by conduction alone. To prevent boiling in reduced pressure environments the maximum temperature of the heating system is severely limited. The Skylab food-heating system utilizes a tray with receptables for the food containers. The walls of the receptacles are lined with thermally controlled, electrical-resistance, blanket-type heating elements. A finite difference model is employed to perform parametric studies on the food-heating system. The effects on heating time of the (1) thermophysical properties of the food, (2) heater power level, (3) initial food temperatures, (4) container geometry, and (5) heater control temperature are presented graphically. The optimal heater power level and container geometry are determined.

  14. The importance of operations, risk, and cost assessment to space transfer systems design

    NASA Technical Reports Server (NTRS)

    Ball, J. M.; Komerska, R. J.; Rowell, L. F.

    1992-01-01

    This paper examines several methodologies which contribute to comprehensive subsystem cost estimation. The example of a space-based lunar space transfer vehicle (STV) design is used to illustrate how including both primary and secondary factors into cost affects the decision of whether to use aerobraking or propulsion for earth orbit capture upon lunar return. The expected dominant cost factor in this decision is earth-to-orbit launch cost driven by STV mass. However, to quantify other significant cost factors, this cost comparison included a risk analysis to identify development and testing costs, a Taguchi design of experiments to determine a minimum mass aerobrake design, and a detailed operations analysis. As a result, the predicted cost advantage of aerobraking, while still positive, was subsequently reduced by about 30 percent compared to the simpler mass-based cost estimates.

  15. A state-space analysis of mechanical energy generation, absorption, and transfer during pedaling.

    PubMed

    Fregly, B J; Zajac, F E

    1996-01-01

    Seated ergometer pedaling is a motor task ideal for studying basic mechanisms of human bipedal coordination because, in contrast to standing and walking, fewer degrees of freedom are being controlled and upright balance is not a factor. As a step toward understanding how individual muscles coordinate pedaling, we investigated how individual net muscle joint torques and non-muscular (e.g. centripetal, coriolis, and gravity) forces of the lower limbs generate, absorb, and transfer mechanical energy in order to propel the crank and recover the limb. This was accomplished using a mechanical power analysis derived entirely from the closed-form state-space dynamical equations of a two-legged pedaling model that accounted for both the limb segmental and crank load dynamics. Based on a pedaling simulation that reproduced experimental kinematic and kinetic trajectories, we found that the net ankle and hip extensor joint torques function 'synergistically' to deliver energy to the crank during the downstroke. The net hip extensor joint torque generates energy to the limb, while the net ankle extensor joint torque transfers this energy from the limb to the crank. In contrast, net knee extensor and flexor joint torques function 'independently' by generating energy to the crank through the top and bottom of the stroke, respectively. The net ankle joint torque transfers and the net knee joint torque generates energy to the crank by contributing to the driving component of the pedal reaction force. During the upstroke, net ankle extensor joint torque transfers energy from the crank to the limb to restore the potential energy of the limb. In both halves of the crank cycle, gravity forces augment the crank-limb energy transfer performed by the net ankle extensor joint torque. PMID:8839020

  16. Higher-order processes of excitation energy transfer in supramolecular complexes: Liouville space analysis of bridge molecule mediated transfer and direct photon exchange.

    PubMed

    May, Volkhard

    2008-09-21

    Long-range electronic excitation energy transfer is studied in the framework of a generalized master equation approach, which offers a systematic account for higher-order processes. Bridge molecule mediated transfer is confronted with the direct excitation energy exchange via photon emission and absorption. It is the central aim of this paper to present a systematic study of fourth-order rates, which describe both types of transfer processes characterized by the presence of intermediate states. While such a Liouville space formulation of rates is known from bridge mediated transfer, it is new for the case of photon mediated processes. In the former case, however, a novel approach to account for intermediate state relaxation is introduced. Finally and for illustration, some estimates are offered for the length dependence of the various discussed transfer rates. PMID:19044952

  17. Transfer of uncertainty of space-borne high resolution rainfall products at ungauged regions

    NASA Astrophysics Data System (ADS)

    Tang, Ling

    Hydrologically relevant characteristics of high resolution (˜ 0.25 degree, 3 hourly) satellite rainfall uncertainty were derived as a function of season and location using a six year (2002-2007) archive of National Aeronautics and Space Administration (NASA)'s Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) precipitation data. The Next Generation Radar (NEXRAD) Stage IV rainfall data over the continental United States was used as ground validation (GV) data. A geostatistical mapping scheme was developed and tested for transfer (i.e., spatial interpolation) of uncertainty information from GV regions to the vast non-GV regions by leveraging the error characterization work carried out in the earlier step. The open question explored here was, "If 'error' is defined on the basis of independent ground validation (GV) data, how are error metrics estimated for a satellite rainfall data product without the need for much extensive GV data?" After a quantitative analysis of the spatial and temporal structure of the satellite rainfall uncertainty, a proof-of-concept geostatistical mapping scheme (based on the kriging method) was evaluated. The idea was to understand how realistic the idea of 'transfer' is for the GPM era. It was found that it was indeed technically possible to transfer error metrics from a gauged to an ungauged location for certain error metrics and that a regionalized error metric scheme for GPM may be possible. The uncertainty transfer scheme based on a commonly used kriging method (ordinary kriging) was then assessed further at various timescales (climatologic, seasonal, monthly and weekly), and as a function of the density of GV coverage. The results indicated that if a transfer scheme for estimating uncertainty metrics was finer than seasonal scale (ranging from 3-6 hourly to weekly-monthly), the effectiveness for uncertainty transfer worsened significantly. Next, a comprehensive assessment of different kriging

  18. An Iterative Phase-Space Explicit Discontinuous Galerkin Method for Stellar Radiative Transfer in Extended Atmospheres

    SciTech Connect

    de Almeida, V.F.

    2004-01-28

    A phase-space discontinuous Galerkin (PSDG) method is presented for the solution of stellar radiative transfer problems. It allows for greater adaptivity than competing methods without sacrificing generality. The method is extensively tested on a spherically symmetric, static, inverse-power-law scattering atmosphere. Results for different sizes of atmospheres and intensities of scattering agreed with asymptotic values. The exponentially decaying behavior of the radiative field in the diffusive-transparent transition region and the forward peaking behavior at the surface of extended atmospheres were accurately captured. The integrodifferential equation of radiation transfer is solved iteratively by alternating between the radiative pressure equation and the original equation with the integral term treated as an energy density source term. In each iteration, the equations are solved via an explicit, flux-conserving, discontinuous Galerkin method. Finite elements are ordered in wave fronts perpendicularly to the characteristic curves so that elemental linear algebraic systems are solved quickly by sweeping the phase space element by element. Two implementations of a diffusive boundary condition at the origin are demonstrated wherein the finite discontinuity in the radiative intensity is accurately captured by the proposed method. This allows for a consistent mechanism to preserve photon luminosity. The method was proved to be robust and fast, and a case is made for the adequacy of parallel processing. In addition to classical two-dimensional plots, results of normalized radiative intensity were mapped onto a log-polar surface exhibiting all distinguishing features of the problem studied.

  19. Development of a Novel Wireless Electric Power Transfer System for Space Applications

    NASA Technical Reports Server (NTRS)

    VazquezRamos, Gabriel; Yuan, Jiann-Shiun

    2011-01-01

    This paper will introduce a new implementation for wireless electric power transfer systems: space applications. Due to the risks that constitute the use of electrical connector for some space missions/applications, a simple wireless power system design approach will be evaluated as an alternative for the use of electrical connectors. This approach takes into consideration the overall system performance by designing the magnetic resonance elements and by verifying the overall system electrical behavior. System characterization is accomplished by executing circuit and analytical simulations using Matlab(TradeMark) and LTSpiceIV(TradeMark) software packages. The design methodology was validated by two different experiments: frequency consideration (design of three magnetic elements) and a small scale proof-ofconcept prototype. Experiment results shows successful wireless power transfer for all the cases studied. The proof-of-concept prototype provided approx.4 W of wireless power to the load (light bulb) at a separation of 3 cm from the source. In addition. a resonant circuit was designed and installed to the battery terminals of a handheld radio without batteries, making it tum on at a separation of approx.5 cm or less from the source. It was also demonstrated by prototype experimentation that multiple loads can be powered wirelessly at the same time with a single electric power source.

  20. Effects of Pin Detached Space on Heat Transfer in a Rib Roughened Channel

    SciTech Connect

    Siw, Sin Chien; Chyu, Minking K.; Alvin, Mary Anne

    2013-03-01

    An experimental study is performed to investigate the heat transfer characteristics and frictional losses in a rib roughened channel combined with detached pin-fins. The overall channel geometry (W = 76.2 mm, E = 25.4 mm) simulates an internal cooling passage of wide aspect ratio (3:1) in a gas turbine airfoil. With a given pin diameter, D = 6.35 mm = [1/4]E, three different pin-fin height-to-diameter ratios, H/D = 4, 3, and 2, were examined. Each of these three cases corresponds to a specific pin array geometry of detachment spacing (C) between the pin-tip and one of the endwalls, i.e., C/D = 0, 1, 2, respectively. The rib height-to-channel height ratio is 0.0625. Two newly proposed cross ribs, namely the broken rib and full rib are evaluated in this effort. The broken ribs are positioned in between two consecutive rows of pin-fins, while the full ribs are fully extended adjacent to the pin-fins. The Reynolds number, based on the hydraulic diameter of the unobstructed cross section and the mean bulk velocity, ranges from 10,000 to 25,000. The experiment employs a hybrid technique based on transient liquid crystal imaging to obtain distributions of the local heat transfer coefficient over all of the participating surfaces, including the endwalls and all pin elements. The presence of ribs enhances local heat transfer coefficient on the endwall substantially by approximately 20% to 50% as compared to the neighboring endwall. In addition, affected by the rib geometry, which is a relatively low profile as compared to the overall height of the channel, the pressure loss seems to be insensitive to the presence of the ribs. However, from the overall heat transfer enhancement standpoint, the baseline cases (without ribs) outperform cases with broken ribs or full ribs.

  1. Finite-thrust optimization of interplanetary transfers of space vehicle with bimodal nuclear thermal propulsion

    NASA Astrophysics Data System (ADS)

    Kharytonov, Oleksii M.; Kiforenko, Boris M.

    2011-08-01

    The nuclear thermal rocket (NTR) propulsion is one of the leading promising technologies for primary space propulsion for manned exploration of the solar system due to its high specific impulse capability and sufficiently high thrust-to-weight ratio. Another benefit of NTR is its possible bimodal design, when nuclear reactor is used for generation of a jet thrust in a high-thrust mode and (with an appropriate power conversion system) as a source of electric power to supply the payload and the electric engines in a low-thrust mode. The model of the NTR thrust control was developed considering high-thrust NTR as a propulsion system of limited power and exhaust velocity. For the proposed model the control of the thrust value is accomplished by the regulation of reactor thermal power and propellant mass flow rate. The problem of joint optimization of the combination of high- and low-thrust arcs and the parameters of bimodal NTR (BNTR) propulsion system is considered for the interplanetary transfers. The interplanetary trajectory of the space vehicle is formed by the high-thrust NTR burns, which define planet-centric maneuvers and by the low-thrust heliocentric arcs where the nuclear electric propulsion (NEP) is used. The high-thrust arcs are analyzed using finite-thrust approach. The motion of the corresponding dynamical system is realized in three phase spaces concerning the departure planet-centric maneuver by means of high-thrust NTR propulsion, the low-thrust NEP heliocentric maneuver and the approach high-thrust NTR planet-centric maneuver. The phase coordinates are related at the time instants of the change of the phase spaces due to the relations between the space vehicle masses. The optimal control analysis is performed using Pontryagin's maximum principle. The numerical results are analyzed for Earth-Mars "sprint" transfer. The optimal values of the parameters that define the masses of NTR and NEP subsystems have been evaluated. It is shown that the low

  2. Space transfer vehicle concepts and requirements study. Volume 2, book 4: Integrated advanced technology development

    NASA Technical Reports Server (NTRS)

    Weber, Gary A.

    1991-01-01

    The Space Transfer Vehicle (STV) program provides both an opportunity and a requirement to increase our upper stage capabilities with the development and applications of new technologies. Issues such as man rating, space basing, reusability, and long lunar surface storage times drive the need for new technology developments and applications. In addition, satisfaction of mission requirements such as lunar cargo delivery capability and lunar landing either require new technology development or can be achieved in a more cost-effective manner with judicious applications of advanced technology. During the STV study, advanced technology development requirements and plans have been addressed by the Technology/Advanced Development Working Group composed of NASA and contractor representatives. This report discusses the results to date of this working group. The first section gives an overview of the technologies that have potential or required applications for the STV and identifies those technologies baselined for the STV. Figures are provided that list the technology categories and show the priority placed on those technology categories for either the space-based or ground-based options. The second section covers the plans and schedules for incorporating the technologies into the STV program.

  3. Heat transfer from combustion gases to a single row of closely spaced tubes in a swirl crossflow Stirling engine heater

    NASA Technical Reports Server (NTRS)

    Bankston, C. P.; Back, L. H.

    1982-01-01

    This paper describes an experimental program to determine the heat-transfer characteristics of a combustor and heat-exchanger system in a hybrid solar receiver which utilizes a Stirling engine. The system consists of a swirl combustor with a crossflow heat exchanger composed of a single row of 48 closely spaced curved tubes. In the present study, heat-transfer characteristics of the combustor/heat-exchanger system without a Stirling engine have been studied over a range of operating conditions and output levels using water as the working fluid. Nondimensional heat-transfer coefficients based on total heat transfer have been obtained and are compared with available literature data. The results show significantly enhanced heat transfer for the present geometry and test conditions. Also, heat transfer along the length of the tubes is found to vary, the effect depending upon test condition.

  4. Transfer of perceptual adaptation to space sickness: What enhances an individual's ability to adapt?

    NASA Technical Reports Server (NTRS)

    1993-01-01

    The objectives of this project were to explore systematically the determiners of transfer of perceptual adaptation as these principles might apply to the space adaptation syndrome. The perceptual experience of an astronaut exposed to the altered gravitational forces involved in spaceflight shares much with that of the subject exposed in laboratory experiments to optically induced visual rearrangement with tilt and dynamic motion illusions such as vection; and experiences and symptoms reported by the trainee who is exposed to the compellingly realistic visual imagery of flight simulators and virtual reality systems. In both of these cases the observer is confronted with a variety of inter- and intrasensory conflicts that initially disrupt perception, as well as behavior, and also produce symptoms of motion sickness.

  5. Concept Design of Cryogenic Propellant Storage and Transfer for Space Exploration

    NASA Technical Reports Server (NTRS)

    Free, James M.; Motil, Susan M.; Kortes, Trudy F.; Meyer, Michael L.; taylor, William J.

    2012-01-01

    NASA is in the planning and investigation process of developing innovative paths for human space exploration that strengthen the capability to extend human and robotic presence beyond low Earth orbit and throughout the solar system. NASA is establishing the foundations to enable humans to safely reach multiple potential destinations, including the Moon, asteroids, Lagrange points, and Mars and its environs through technology and capability development. To achieve access to these destinations within a reasonable flight time will require the use of high performance cryogenic propulsion systems. Therefore NASA is examining mission concepts for a Cryogenic Propellant Storage and Transfer (CPST) Flight Demonstration which will test and validate key capabilities and technologies required for future exploration elements such as large cryogenic propulsion stages and propellant depots. The CPST project will perform key ground testing in fiscal year 2012 and execute project formulation and implementation leading to a flight demonstration in 2017.

  6. Instantaneous heat transfer coefficient based upon two-dimensional analyses of Stirling space engine components

    NASA Technical Reports Server (NTRS)

    Ibrahim, Mounir; Kannapareddy, Mohan; Tew, Roy C.; Dudenhoefer, James E.

    1991-01-01

    Twelve different cases of multidimensional models of Stirling engine components for space applications have been numerically investigated for oscillating, incompressible laminar flow with heat transfer. The cases studied covered wide ranges of Valensi number (from 44 to 700), Re(max) number (from 8250 to 60,000), and relative amplitude of fluid motion of 0.686 and 1.32. The Nusselt numbers obtained from the present study indicate a very complex shape with respect to time and axial location in the channel. The results indicate that three parameters can be used to define the local Nusselt number variation, namely: time average, amplitude, and phase angle. These parameters could be correlated respectively using: Re(max), Va and Re(max), and the relative amplitude of fluid motion.

  7. Numerical Study of the Generation of Linear Energy Transfer Spectra for Space Radiation Applications

    NASA Technical Reports Server (NTRS)

    Badavi, Francis F.; Wilson, John W.; Hunter, Abigail

    2005-01-01

    In analyzing charged particle spectra in space due to galactic cosmic rays (GCR) and solar particle events (SPE), the conversion of particle energy spectra into linear energy transfer (LET) distributions is a convenient guide in assessing biologically significant components of these spectra. The mapping of LET to energy is triple valued and can be defined only on open energy subintervals where the derivative of LET with respect to energy is not zero. Presented here is a well-defined numerical procedure which allows for the generation of LET spectra on the open energy subintervals that are integrable in spite of their singular nature. The efficiency and accuracy of the numerical procedures is demonstrated by providing examples of computed differential and integral LET spectra and their equilibrium components for historically large SPEs and 1977 solar minimum GCR environments. Due to the biological significance of tissue, all simulations are done with tissue as the target material.

  8. Optical space weathering on Vesta: Radiative-transfer models and Dawn observations

    NASA Astrophysics Data System (ADS)

    Blewett, David T.; Denevi, Brett W.; Le Corre, Lucille; Reddy, Vishnu; Schröder, Stefan E.; Pieters, Carle M.; Tosi, Federico; Zambon, Francesca; De Sanctis, Maria Cristina; Ammannito, Eleonora; Roatsch, Thomas; Raymond, Carol A.; Russell, Christopher T.

    2016-02-01

    Exposure to ion and micrometeoroid bombardment in the space environment causes physical and chemical changes in the surface of an airless planetary body. These changes, called space weathering, can strongly influence a surface's optical characteristics, and hence complicate interpretation of composition from reflectance spectroscopy. Prior work using data from the Dawn spacecraft (Pieters, C.M. et al. [2012]. Nature 491, 79-82) found that accumulation of nanophase metallic iron (npFe0), which is a key space-weathering product on the Moon, does not appear to be important on Vesta, and instead regolith evolution is dominated by mixing with carbonaceous chondrite (CC) material delivered by impacts. In order to gain further insight into the nature of space weathering on Vesta, we constructed model reflectance spectra using Hapke's radiative-transfer theory and used them as an aid to understanding multispectral observations obtained by Dawn's Framing Cameras (FC). The model spectra, for a howardite mineral assemblage, include both the effects of npFe0 and that of a mixed CC component. We found that a plot of the 438-nm/555-nm ratio vs. the 555-nm reflectance for the model spectra helps to separate the effects of lunar-style space weathering (LSSW) from those of CC-mixing. We then constructed ratio-reflectance pixel scatterplots using FC images for four areas of contrasting composition: a eucritic area at Vibidia crater, a diogenitic area near Antonia crater, olivine-bearing material within Bellicia crater, and a light mantle unit (referred to as an "orange patch" in some previous studies, based on steep spectral slope in the visible) northeast of Oppia crater. In these four cases the observed spectral trends are those expected from CC-mixing, with no evidence for weathering dominated by production of npFe0. In order to survey a wider range of surfaces, we also defined a spectral parameter that is a function of the change in 438-nm/555-nm ratio and the 555-nm reflectance

  9. Technology Solutions Case Study: Air Leakage and Air Transfer Between Garage and Living Space, Waldorf, Maryland

    SciTech Connect

    2014-11-01

    In this project, Building Science Corporation worked with production homebuilder K. Hovnanian to evaluate air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multipoint fan pressurization tests and additional zone pressure diagnostic testing measured the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  10. Laser ranging application to time transfer using geodetic satellite and to other Japanese space programs

    NASA Technical Reports Server (NTRS)

    Kunimori, Hiroo; Takahashi, Fujinobu; Itabe, Toshikazu; Yamamoto, Atsushi

    1993-01-01

    Communications Research Laboratory (CRL) has been developing a laser time transfer system using a satellite laser ranging (SLR) system. We propose Japanese geodetic satellite 'AJISAI', launched in 1986 as a target satellite. The surface is covered not only with corner cube reflectors but also with mirrors. The mirrors are originally designed for observation of flushing solar light reflected by the separate mirrors while the satellite is spinning. In the experiment, synchronized laser pulses are transferred via specified mirror from one station to another while the satellite is up on the horizon to both stations. The system is based on the epoch timing ranging system with 40 ps ranging precision, connected together with UTC(CRL). Simulation study indicates that two stations at thousands of km distance from each other can be linked with signal strength of more than 10 photons and the distributed images of laser beam from AJISAI mirrors give many chances for two stations to link each other during a single AJISAI pass. Retro-reflector In Space for Advanced Earth Observation Satellite (ADEOS) and RendDezVous docking mission of Experimental Technology Satellite-7 (ETS-7) are briefly presented.

  11. An improved model of charge transfer inefficiency and correction algorithm for the Hubble Space Telescope

    NASA Astrophysics Data System (ADS)

    Massey, Richard; Schrabback, Tim; Cordes, Oliver; Marggraf, Ole; Israel, Holger; Miller, Lance; Hall, David; Cropper, Mark; Prod'homme, Thibaut; Niemi, Sami-Matias

    2014-03-01

    Charge-coupled device (CCD) detectors, widely used to obtain digital imaging, can be damaged by high energy radiation. Degraded images appear blurred, because of an effect known as Charge Transfer Inefficiency (CTI), which trails bright objects as the image is read out. It is often possible to correct most of the trailing during post-processing, by moving flux back to where it belongs. We compare several popular algorithms for this: quantifying the effect of their physical assumptions and tradeoffs between speed and accuracy. We combine their best elements to construct a more accurate model of damaged CCDs in the Hubble Space Telescope's Advanced Camera for Surveys/Wide Field Channel, and update it using data up to early 2013. Our algorithm now corrects 98 per cent of CTI trailing in science exposures, a substantial improvement over previous work. Further progress will be fundamentally limited by the presence of read noise. Read noise is added after charge transfer so does not get trailed - but it is incorrectly untrailed during post-processing.

  12. Space-based laser-powered orbital transfer vehicle (Project SLICK)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The project SLICK (Space Laser Interorbital Cargo Kite) involves conceptual designs of reusable space-based laser-powered orbital transfer vehicle (LOTV) for ferrying 16,000 kg cargo primarily between low Earth orbit (LEO) and geosynchronous earth orbit (GEO). The power of LOTV is beamed by a single 32-MW solar-pumped iodide laser orbiting the Earth at an altitude of one Earth radius. The laser engine selected for the LOTV is based on a continuous-wave, steady-state propulsion scheme and uses an array of seven discrete plasmas in a flow of hydrogen propellant. Both all-propulsive and aerobraked LOTV configurations were analyzed and developed. The all-propulsive vehicle uses a rigid 11.5-m aperture primary mirror and its engine produces a thrust of 2000 N at a specific impulse of 1500 sec. For the LEO-to-GEO trip, the payload ratio, m(sub payload/m(sub propellant)+m(sub dry vehicle) = 1.19 and the trip time is about 6 days. The aerobraked version uses a lightweight, retractable wrapped-rib primary mirror which is folded for aerobraking and a 20-m-diameter inflatable-ballute aeroshield which is jettisoned after aeromaneuver. Lifecycle cost analysis shows that the aerobraked configuration may have an economic advantage over the all-propulsive configuration as long as the cost of launching the propellant to LEO is higher than about $500/kg in current dollars.

  13. The development and technology transfer of software engineering technology at NASA. Johnson Space Center

    NASA Technical Reports Server (NTRS)

    Pitman, C. L.; Erb, D. M.; Izygon, M. E.; Fridge, E. M., III; Roush, G. B.; Braley, D. M.; Savely, R. T.

    1992-01-01

    The United State's big space projects of the next decades, such as Space Station and the Human Exploration Initiative, will need the development of many millions of lines of mission critical software. NASA-Johnson (JSC) is identifying and developing some of the Computer Aided Software Engineering (CASE) technology that NASA will need to build these future software systems. The goal is to improve the quality and the productivity of large software development projects. New trends are outlined in CASE technology and how the Software Technology Branch (STB) at JSC is endeavoring to provide some of these CASE solutions for NASA is described. Key software technology components include knowledge-based systems, software reusability, user interface technology, reengineering environments, management systems for the software development process, software cost models, repository technology, and open, integrated CASE environment frameworks. The paper presents the status and long-term expectations for CASE products. The STB's Reengineering Application Project (REAP), Advanced Software Development Workstation (ASDW) project, and software development cost model (COSTMODL) project are then discussed. Some of the general difficulties of technology transfer are introduced, and a process developed by STB for CASE technology insertion is described.

  14. Generation of multiple optical frequencies referenced to a frequency comb for precision free-space frequency transfer

    NASA Astrophysics Data System (ADS)

    Chun, Byung Jae; Kang, Hyun Jay; Kim, Young-Jin; Kim, Seung-Woo

    2016-03-01

    Generating multiple optical frequencies referenced to the frequency standard is an important task in optical clock dissemination and optical communication. An apparatus for frequency-comb-referenced generation of multiple optical frequencies is demonstrated for high-precision free-space transfer of multiple optical frequencies. The relative linewidth and frequency instability at each channel corresponds to sub-1 Hz and 1.06×10-15 at 10 s averaging time, respectively. During the free-space transfer, the refractive index change of transmission media caused by atmospheric turbulences induces phase and frequency noise on optical frequencies. These phase and frequency noise causes induced linewidth broadening and frequency shift in optical frequencies which can disturb the accurate frequency transfer. The proposed feedback loop with acousto-optic modulator can monitor and compensate phase/frequency noise on optical frequencies. As a result, a frequency-comb-referenced single optical mode is compensated with a high signal to noise ratio (SNR) of 80 dB. By sharing the same optical paths, this feedback loop is confirmed to be successfully transferred to the neighboring wavelength channels (a 100 GHz spaced channel). This result confirms our proposed system can transfer optical frequencies to the remote site in free-space without performance degradation.

  15. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 6: Lunar systems

    NASA Technical Reports Server (NTRS)

    1991-01-01

    NASA's two Office of Space Flight (Code M) Space Transfer Vehicle (STV) contractors supported development of Space Exploration Initiative (SEI) lunar transportation concepts. This work treated lunar SEI missions as the far end of a more near-term STV program, most of whose missions were satellite delivery and servicing requirements derived from Civil Needs Data Base (CNDB) projections. Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) began to address the complete design of a lunar transportation system. The following challenges were addressed: (1) the geometry of aerobraking; (2) accommodation of mixed payloads; (3) cryogenic propellant transfer in Low Lunar Orbit (LLO); (4) fully re-usable design; and (5) growth capability. The leveled requirements, derived requirements, and assumptions applied to the lunar transportation system design are discussed. The mission operations section includes data on mission analysis studies and performance parametrics as well as the operating modes and performance evaluations which include the STCAEM recommendations. Element descriptions for the lunar transportation family included are a listing of the lunar transfer vehicle/lunar excursion vehicle (LTV/LEV) components; trade studies and mass analyses of the transfer and excursion modules; advanced crew recovery vehicle (ACRV) (modified crew recovery vehicle (MCRV)) modifications required to fulfill lunar operations; the aerobrake shape and L/D to be used; and some costing methods and results. Commonality and evolution issues are also discussed.

  16. Space transfer vehicle concepts and requirements study. Volume 3: Program cost estimates. Book 2: WBS and dictionary

    NASA Technical Reports Server (NTRS)

    Peffley, A. F.

    1991-01-01

    This document describes the products and services to be developed, tested, produced, and operated for the Space Transfer Vehicle (STV) Program. The Work Breakdown Structure (WBS) and WBS Dictionary are program management tools used to catalog, account by task, and summarize work packages of a space system program. The products or services to be delivered or accomplished during the STV C/D phase are the primary focus of this work breakdown structure document.

  17. Improved time-space method for 3-D heat transfer problems including global warming

    SciTech Connect

    Saitoh, T.S.; Wakashima, Shinichiro

    1999-07-01

    In this paper, the Time-Space Method (TSM) which has been proposed for solving general heat transfer and fluid flow problems was improved in order to cover global and urban warming. The TSM is effective in almost all-transient heat transfer and fluid flow problems, and has been already applied to the 2-D melting problems (or moving boundary problems). The computer running time will be reduced to only 1/100th--1/1000th of the existing schemes for 2-D and 3-D problems. However, in order to apply to much larger-scale problems, for example, global warming, urban warming and general ocean circulation, the SOR method (or other iterative methods) in four dimensions is somewhat tedious and provokingly slow. Motivated by the above situation, the authors improved the speed of iteration of the previous TSM by introducing the following ideas: (1) Timewise chopping: Time domain is chopped into small peaches to save memory requirement; (2) Adaptive iteration: Converged region is eliminated for further iteration; (3) Internal selective iteration: Equation with slow iteration speed in iterative procedure is selectively iterated to accelerate entire convergence; and (4) False transient integration: False transient term is added to the Poisson-type equation and the relevant solution is regarded as a parabolic equation. By adopting the above improvements, the higher-order finite different schemes and the hybrid mesh, the computer running time for the TSM is reduced to some 1/4600th of the conventional explicit method for a typical 3-D natural convection problem in a closed cavity. The proposed TSM will be more efficacious for large-scale environmental problems, such as global warming, urban warming and general ocean circulation, in which a tremendous computing time would be required.

  18. Space-based laser-powered orbital transfer vehicle (Project SLICK)

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A conceptual design study of a laser-powered orbital transfer vehicle (LOTV) is presented. The LOTV, nicknamed SLICK (Space Laser Interorbital Cargo Kite), will be utilized for the transfer of 16000 kg of cargo between Low Earth Orbit (LEO) and either Geosynchronous Earth Orbit (GEO) or Low Lunar Orbit (LLO). This design concentrates primarily on the LEO/GEO scenario, which will have typical LEO-to-GEO trip time of 6 days and two return versions. One version uses an all propulsive return while the other utilizes a ballute aerobrake for the return trip. Furthermore, three return cargo options of 16000 kg, 5000 kg (standard option), and 1600 kg are considered for this scenario. The LEO/LLO scenario uses only a standard, aerobraked version. The basic concept behind the LOTV is that the power for the propulsion system is supplied by a source separate from the LOTV itself. For the LEO/GEO scenario the LOTV utilizes a direct solar-pumped iodide laser and possibly two relay stations, all orbiting at an altitude of one Earth radius and zero inclination. An additional nuclear-powered laser is placed on the Moon for the LEO/LLO scenario. The propulsion system of the LOTV consists of a single engine fueled with liquid hydrogen. The laser beam is captured and directed by a four mirror optical system through a window in the thrust chamber of the engine. There, seven plasmas are created to convert the laser beam energy into thermal energy at an efficiency of at least 50 percent. For the LEO/LLO scenario the laser propulsion is supplemented by LH2/LOX chemical thrusters.

  19. Nonequilibrium radiative heating prediction method for aeroassist flowfields with coupling to flowfield solvers. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Hartung, Lin C.

    1991-01-01

    A method for predicting radiation adsorption and emission coefficients in thermochemical nonequilibrium flows is developed. The method is called the Langley optimized radiative nonequilibrium code (LORAN). It applies the smeared band approximation for molecular radiation to produce moderately detailed results and is intended to fill the gap between detailed but costly prediction methods and very fast but highly approximate methods. The optimization of the method to provide efficient solutions allowing coupling to flowfield solvers is discussed. Representative results are obtained and compared to previous nonequilibrium radiation methods, as well as to ground- and flight-measured data. Reasonable agreement is found in all cases. A multidimensional radiative transport method is also developed for axisymmetric flows. Its predictions for wall radiative flux are 20 to 25 percent lower than those of the tangent slab transport method, as expected, though additional investigation of the symmetry and outflow boundary conditions is indicated. The method was applied to the peak heating condition of the aeroassist flight experiment (AFE) trajectory, with results comparable to predictions from other methods. The LORAN method was also applied in conjunction with the computational fluid dynamics (CFD) code LAURA to study the sensitivity of the radiative heating prediction to various models used in nonequilibrium CFD. This study suggests that radiation measurements can provide diagnostic information about the detailed processes occurring in a nonequilibrium flowfield because radiation phenomena are very sensitive to these processes.

  20. Autonomous rendezvous and docking operations of unmanned expendable cargo transfer vehicles (e.g. Centaur) with Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Emmet, Brian R.

    1991-01-01

    This paper describes the results of the feasibility study using Centaur or other CTV's to deliver payloads to the Space Station Freedom (SSF). During this study was examined the requirements upon unmanned cargo transfer stages (including Centaur) for phasing, rendezvous, proximity operations and docking/berthing (capture).

  1. Experimental determination of convective heat transfer coefficients in the separated flow region of the Space Shuttle Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    Whitesides, R. Harold; Majumdar, Alok K.; Jenkins, Susan L.; Bacchus, David L.

    1990-01-01

    A series of cold flow heat transfer tests was conducted with a 7.5-percent scale model of the Space Shuttle Rocket Motor (SRM) to measure the heat transfer coefficients in the separated flow region around the nose of the submerged nozzle. Modifications were made to an existing 7.5 percent scale model of the internal geometry of the aft end of the SRM, including the gimballed nozzle in order to accomplish the measurements. The model nozzle nose was fitted with a stainless steel shell with numerous thermocouples welded to the backside of the thin wall. A transient 'thin skin' experimental technique was used to measure the local heat transfer coefficients. The effects of Reynolds number, nozzle gimbal angle, and model location were correlated with a Stanton number versus Reynolds number correlation which may be used to determine the convective heating rates for the full scale Space Shuttle Solid Rocket Motor nozzle.

  2. Measurement of Linear Energy Transfer Spectra of High-LET Space Radiation Inside the International Space Station Modules (2013-2014)

    NASA Astrophysics Data System (ADS)

    Inozemtsev, K. O.; Kushin, V. V.; Maklyaev, E. F.; Shurshakov, V. A.

    The field of space radiation in low-Earth orbit is extremely complicated due to many reasons. It is formed mainly of galactic cosmic rays (GCR), solar particles and trapped particles in the south Atlantic anomaly region. In addition radiation field is affected by shielding and scattering of incident primary particles by surrounding material. The contribution of short - range particles produced in the nuclear interactions in the shielding and contents of the spacecraft to the total radiation field is comparable to the primary component at high values of dE/dx. Preliminary linear energy transfer (LET) spectra of high-LET space radiation were measured in different compartments of the Russian segment of International Space Station (ISS) by means of plastic nuclear track detectors (PNTD) CR-39 TASTRACK. Measurements were carried out during ISS-37/38/39 expeditions in MATROSHKA-R space experiment. The comparison of experimental spectra with simulated one was made in order of data verification.

  3. International two-way satellite time transfers using INTELSAT space segment and small Earth stations

    NASA Astrophysics Data System (ADS)

    Veenstra, Lester B.

    1990-05-01

    The satellite operated by the International Telecommunications Satellite Organization (INTELSAT) provides new and unique capabilities for the coordinates of international time scales on a world wide basis using the two-way technique. A network of coordinated clocks using small earth stations collocated with the scales is possible. Antennas as small as 1.8 m at K-band and 3 m at C-band transmitting powers of less than 1 W will provide signals with time jitters of less than 1 ns existing spread spectrum modems. One way time broadcasting is also possible, under the INTELSAT INTELNET system, possibly using existing international data distribution (press and financial) systems that are already operating spread spectrum systems. The technical details of the satellite and requirements on satellite earth stations are given. The resources required for a regular operational international time transfer service are analyzed with respect to the existing international digital service offerings of the INTELSAT Business Service (IBS) and INTELNET. Coverage areas, typical link budgets, and a summary of previous domestic and international work using this technique are provided. Administrative procedures for gaining access to the space segment are outlined. Contact information for local INTELSAT signatories is listed.

  4. Space transfer vehicle concepts and requirements study. Volume 3, book 1: Program cost estimates

    NASA Astrophysics Data System (ADS)

    Peffley, Al F.

    1991-04-01

    The Space Transfer Vehicle (STV) Concepts and Requirements Study cost estimate and program planning analysis is presented. The cost estimating technique used to support STV system, subsystem, and component cost analysis is a mixture of parametric cost estimating and selective cost analogy approaches. The parametric cost analysis is aimed at developing cost-effective aerobrake, crew module, tank module, and lander designs with the parametric cost estimates data. This is accomplished using cost as a design parameter in an iterative process with conceptual design input information. The parametric estimating approach segregates costs by major program life cycle phase (development, production, integration, and launch support). These phases are further broken out into major hardware subsystems, software functions, and tasks according to the STV preliminary program work breakdown structure (WBS). The WBS is defined to a low enough level of detail by the study team to highlight STV system cost drivers. This level of cost visibility provided the basis for cost sensitivity analysis against various design approaches aimed at achieving a cost-effective design. The cost approach, methodology, and rationale are described. A chronological record of the interim review material relating to cost analysis is included along with a brief summary of the study contract tasks accomplished during that period of review and the key conclusions or observations identified that relate to STV program cost estimates. The STV life cycle costs are estimated on the proprietary parametric cost model (PCM) with inputs organized by a project WBS. Preliminary life cycle schedules are also included.

  5. International two-way satellite time transfers using INTELSAT space segment and small Earth stations

    NASA Technical Reports Server (NTRS)

    Veenstra, Lester B.

    1990-01-01

    The satellite operated by the International Telecommunications Satellite Organization (INTELSAT) provides new and unique capabilities for the coordinates of international time scales on a world wide basis using the two-way technique. A network of coordinated clocks using small earth stations collocated with the scales is possible. Antennas as small as 1.8 m at K-band and 3 m at C-band transmitting powers of less than 1 W will provide signals with time jitters of less than 1 ns existing spread spectrum modems. One way time broadcasting is also possible, under the INTELSAT INTELNET system, possibly using existing international data distribution (press and financial) systems that are already operating spread spectrum systems. The technical details of the satellite and requirements on satellite earth stations are given. The resources required for a regular operational international time transfer service are analyzed with respect to the existing international digital service offerings of the INTELSAT Business Service (IBS) and INTELNET. Coverage areas, typical link budgets, and a summary of previous domestic and international work using this technique are provided. Administrative procedures for gaining access to the space segment are outlined. Contact information for local INTELSAT signatories is listed.

  6. Space transfer vehicle concepts and requirements study. Volume 3, book 1: Program cost estimates

    NASA Technical Reports Server (NTRS)

    Peffley, Al F.

    1991-01-01

    The Space Transfer Vehicle (STV) Concepts and Requirements Study cost estimate and program planning analysis is presented. The cost estimating technique used to support STV system, subsystem, and component cost analysis is a mixture of parametric cost estimating and selective cost analogy approaches. The parametric cost analysis is aimed at developing cost-effective aerobrake, crew module, tank module, and lander designs with the parametric cost estimates data. This is accomplished using cost as a design parameter in an iterative process with conceptual design input information. The parametric estimating approach segregates costs by major program life cycle phase (development, production, integration, and launch support). These phases are further broken out into major hardware subsystems, software functions, and tasks according to the STV preliminary program work breakdown structure (WBS). The WBS is defined to a low enough level of detail by the study team to highlight STV system cost drivers. This level of cost visibility provided the basis for cost sensitivity analysis against various design approaches aimed at achieving a cost-effective design. The cost approach, methodology, and rationale are described. A chronological record of the interim review material relating to cost analysis is included along with a brief summary of the study contract tasks accomplished during that period of review and the key conclusions or observations identified that relate to STV program cost estimates. The STV life cycle costs are estimated on the proprietary parametric cost model (PCM) with inputs organized by a project WBS. Preliminary life cycle schedules are also included.

  7. James Webb Space Telescope segment phasing using differential optical transfer functions

    PubMed Central

    Codona, Johanan L.; Doble, Nathan

    2015-01-01

    Differential optical transfer function (dOTF) is an image-based, noniterative wavefront sensing method that uses two star images with a single small change in the pupil. We describe two possible methods for introducing the required pupil modification to the James Webb Space Telescope, one using a small (<λ/4) displacement of a single segment's actuator and another that uses small misalignments of the NIRCam's filter wheel. While both methods should work with NIRCam, the actuator method will allow both MIRI and NIRISS to be used for segment phasing, which is a new functionality. Since the actuator method requires only small displacements, it should provide a fast and safe phasing alternative that reduces the mission risk and can be performed frequently for alignment monitoring and maintenance. Since a single actuator modification can be seen by all three cameras, it should be possible to calibrate the non-common-path aberrations between them. Large segment discontinuities can be measured using dOTFs in two filter bands. Using two images of a star field, aberrations along multiple lines of sight through the telescope can be measured simultaneously. Also, since dOTF gives the pupil field amplitude as well as the phase, it could provide a first approximation or constraint to the planned iterative phase retrieval algorithms. PMID:27042684

  8. James Webb Space Telescope segment phasing using differential optical transfer functions

    NASA Astrophysics Data System (ADS)

    Codona, Johanan L.; Doble, Nathan

    2015-04-01

    Differential optical transfer function (dOTF) is an image-based, noniterative wavefront sensing method that uses two star images with a single small change in the pupil. We describe two possible methods for introducing the required pupil modification to the James Webb Space Telescope, one using a small (<λ/4) displacement of a single segment's actuator and another that uses small misalignments of the NIRCam's filter wheel. While both methods should work with NIRCam, the actuator method will allow both MIRI and NIRISS to be used for segment phasing, which is a new functionality. Since the actuator method requires only small displacements, it should provide a fast and safe phasing alternative that reduces the mission risk and can be performed frequently for alignment monitoring and maintenance. Since a single actuator modification can be seen by all three cameras, it should be possible to calibrate the non-common-path aberrations between them. Large segment discontinuities can be measured using dOTFs in two filter bands. Using two images of a star field, aberrations along multiple lines of sight through the telescope can be measured simultaneously. Also, since dOTF gives the pupil field amplitude as well as the phase, it could provide a first approximation or constraint to the planned iterative phase retrieval algorithms.

  9. Orbital transfer vehicle concept definition and system analysis study. Volume 4, Appendix A: Space station accommodations. Revision 1

    NASA Technical Reports Server (NTRS)

    Randall, Roger M.

    1987-01-01

    Orbit Transfer Vehicle (OTV) processing at the space station is divided into two major categories: OTV processing and assembly operations, and support operations. These categories are further subdivided into major functional areas to allow development of detailed OTV processing procedures and timelines. These procedures and timelines are used to derive the specific space station accommodations necessary to support OTV activities. The overall objective is to limit impact on OTV processing requirements on space station operations, involvement of crew, and associated crew training and skill requirements. The operational concept maximizes use of automated and robotic systems to perform all required OTV servicing and maintenance tasks. Only potentially critical activities would require direct crew involvement or supervision. EVA operations are considered to be strictly contingency back-up to failure of the automated and robotic systems, with the exception of the initial assembly of Space-Based OTV accommodations at the space station, which will require manned involvement.

  10. Effect of mineral dust on ocean color retrievals from space: A radiative transfer simulation study

    NASA Astrophysics Data System (ADS)

    Ahmad, Z.; Franz, B. A.

    2014-12-01

    Mineral aerosols (dust) are one of the major components of all aerosols found in the Earth's atmosphere. They are mainly soil particles that originate from arid and semiarid regions of the world that can be carried by winds for thousands of kilometers. They are a major impediment in the remote sensing of the ocean color (spectral water-leaving reflectance), because they absorb solar radiation in the UV and visible part of the spectrum and their micro-physical and optical properties are highly variable. Further, there are no reliable working algorithms to detect their presence from spaceborne ocean color observations alone, when they are present in small amount (optical thickness < 0.2). In this paper we examine effect of mineral dust on ocean color retrieval from space. We use Ahmad-Fraser's vector radiative transfer (RT) code (v3.0) for ocean-atmosphere system to simulate the pseudo observations (top of atmosphere radiance) for models containing different types of aerosols (absorbing and non-absorbing) in the atmosphere. We consider the mineral aerosols as consisting of an external mixture of illite, kaolinite, montmorillonite, quartz, and calcite with a small amount of hematite (as an internal mixture), which provide the spectral dependence of single scattering albedo consistent with the values reported in the literature. We also vary the aerosol layer height in the atmosphere and amount of chlorophyll in the ocean. The simulated pseudo observations were processed through standard NASA algorithms to determine the ocean color (spectral water-leaving reflectance) and derived chlorophyll in the ocean. Results of the RT simulation study for different Sun-satellite viewing geometry, aerosol layer height and chlorophyll amount in the ocean is presented.

  11. Improving Sensorimotor Adaptation Following Long Duration Space Flight by Enhancing Vestibular Information Transfer

    NASA Technical Reports Server (NTRS)

    Mulavara, A. P.; Kofman, I. S.; De Dios, Y. E; Galvan, R.; Goel, R.; Miller, C.; Peters, B.; Cohen, H. S.; Jeevarajan, J.; Reschke, M.; Wood, S.; Bergquist, F.; Seidler, R. D.; Bloomberg, J. J.

    2014-01-01

    Crewmember adapted to the microgravity state may need to egress the vehicle within a few minutes for safety and operational reasons after gravitational transitions. The transition from one sensorimotor state to another consists of two main mechanisms: strategic and plastic-adaptive and have been demonstrated in astronauts returning after long duration space flight. Strategic modifications represent "early adaptation" - immediate and transitory changes in control that are employed to deal with short-term changes in the environment. If these modifications are prolonged then plastic-adaptive changes are evoked that modify central nervous system function, automating new behavioral responses. More importantly, this longer term adaptive recovery mechanism was significantly associated with their strategic ability to recover on the first day after return to Earth G. We are developing a method based on stochastic resonance to enhance information transfer by improving the brain's ability to detect vestibular signals (Vestibular Stochastic Resonance, VSR) especially when combined with balance training exercises such as sensorimotor adaptability (SA) training for rapid improvement in functional skill, for standing and mobility. This countermeasure to improve detection of vestibular signals is a stimulus delivery system that is wearable/portable providing low imperceptible levels of white noise based binaural bipolar electrical stimulation of the vestibular system (stochastic vestibular stimulation). To determine efficacy of vestibular stimulation on physiological and perceptual responses during otolith-canal conflicts and dynamic perturbations we have conducted a series of studies: We have shown that imperceptible binaural bipolar electrical stimulation of the vestibular system across the mastoids enhances balance performance in the mediolateral (ML) plane while standing on an unstable surface. We have followed up on the previous study showing VSR stimulation improved balance

  12. Radiative transfer to space through a precipitating cloud at multiple microwave frequencies. I - Model description. II - Results and analysis

    NASA Technical Reports Server (NTRS)

    Mugnai, Alberto; Smith, Eric A.

    1988-01-01

    The impact of time-dependent cloud microphysical structure on the transfer to space of passive microwave radiation is studied at several frequencies across the EHF and lower SHF portions of the microwave spectrum. The feasibility of using multichannel passive-microwave retrieval techniques to estimate precipitation from space-based platforms is examined. The model is described, and the results are assessed in conjunction with a Nimbus-7 SMMR case study of precipitation in an intense tropical Pacific storm. It is concluded that the effects of cloud liquid water content must be considered to obtain a realistic estimation and distribution of rainrates.

  13. Space transfer concepts and analyses for exploration missions. Technical directive 12: Beamed power systems study

    NASA Technical Reports Server (NTRS)

    Eder, D.

    1992-01-01

    Parametric models were constructed for Earth-based laser powered electric orbit transfer from low Earth orbit to geosynchronous orbit. These models were used to carry out performance, cost/benefit, and sensitivity analyses of laser-powered transfer systems including end-to-end life cycle cost analyses for complete systems. Comparisons with conventional orbit transfer systems were made indicating large potential cost savings for laser-powered transfer. Approximate optimization was done to determine best parameter values for the systems. Orbit transfer flights simulations were conducted to explore effects of parameters not practical to model with a spreadsheet. The simulations considered view factors that determine when power can be transferred from ground stations to an orbit transfer vehicle and conducted sensitivity analyses for numbers of ground stations, Isp including dual-Isp transfers, and plane change profiles. Optimal steering laws were used for simultaneous altitude and plane change. Viewing geometry and low-thrust orbit raising were simultaneously simulated. A very preliminary investigation of relay mirrors was made.

  14. Future directions in two-phase flow and heat transfer in space

    NASA Technical Reports Server (NTRS)

    Bankoff, S. George

    1994-01-01

    Some areas of opportunity for future research in microgravity two-phase flow and heat transfer are pointed out. These satisfy the dual requirements of relevance to current and future needs, and scientific/engineering interest.

  15. Ion-atom charge-transfer reactions and a hot intercloud medium. [in interstellar space

    NASA Technical Reports Server (NTRS)

    Steigman, G.

    1975-01-01

    An investigation is conducted concerning the ionization equilibrium of carbon in a hot intercloud medium (ICM), taking into account various charge-transfer reactions. Attention is given to problems related to observations of carbon along the lines of sight to several unreddened stars. It is pointed out that the observed underabundance of C III and overabundance of C I can be consistent with the presence of a hot, partially ionized ICM, provided that two of the charge-transfer reactions considered are rapid at thermal energies.

  16. Plant architecture, growth and radiative transfer for terrestrial and space environments

    NASA Technical Reports Server (NTRS)

    Norman, John M.; Goel, Narendra S.

    1993-01-01

    The overall objective of this research was to develop a hardware implemented model that would incorporate realistic and dynamic descriptions of canopy architecture in physiologically based models of plant growth and functioning, with an emphasis on radiative transfer while accommodating other environmental constraints. The general approach has five parts: a realistic mathematical treatment of canopy architecture, a methodology for combining this general canopy architectural description with a general radiative transfer model, the inclusion of physiological and environmental aspects of plant growth, inclusion of plant phenology, and integration.

  17. Pressure and heat transfer investigation of a modified NASP baseline configuration at M = 6. [National Aero-Space Plane

    NASA Technical Reports Server (NTRS)

    Reubush, David E.; Omar, M. Emmett

    1989-01-01

    A cooperative NASA Langley-Boeing investigation was conducted in the Langley eight-Foot High Temperature Tunnel to obtain hypersonic pressure and heat transfer data. In this investigation a large scale (1/20), modified version of the National Aero-Space Plane configuration known as the 'Government Baseline' was tested at a nominal Mach number of 6; at two Reynolds numbers (0.6 and 1.6 million per foot); and at angles of attack from about 0 to 15 deg. There were several purposes for the investigation: to provide a windward and leeward pressure and heat transfer data base for a realistic configuration for verification of computational methods, to provide these data for a large-scale model, and to provide these data for true temperature conditions because of concern about data from low temperature tunnels.

  18. Pioneering space research in the ussr and mathematical modelling of large problem of radiation transfer

    NASA Astrophysics Data System (ADS)

    Sushkevich, T. A.

    2011-09-01

    This review is to recall to scientists of the older generation about some historical pages of our memory and about many famous researchers, teachers and colleagues. As to the younger researchers and foreign colleagues, it will be useful for them to get to know about pioneer advancements of the Soviet scientists in the field of information and mathematical supply for cosmonautic problems on the eve of the space era. Main attention is paid down to the scientific experiments conducted on the piloted space vehicles and the research collectives who created the information and mathematical tools for the first space projects. The role of Mstislav Vsevolodovich Keldysh, the Major Theoretician of cosmonautics, is in particular emphasized, who determined in the most degree the basic directions of development of space research and remote sensing of the Earth and planets that are shortly called as REMOTE SENSING.

  19. Development and construction of the photon counting receiver for the European laser time transfer space mission

    NASA Astrophysics Data System (ADS)

    Prochazka, Ivan; Blazej, Josef; Kodet, Jan; Brinek, Jan

    2011-06-01

    We are presenting the work progress and recent results in the development and construction of the photon counting receiver, which is prepared for the European Laser Timing experiment in space. It is an optical link prepared in the frame of the ESA mission Atomic Clock Ensemble in Space. The ultra short laser pulses will be used to synchronize the time scales ground to space with picosecond precision. To minimize the timing biases the photon counting concept of the space born receiver was selected. The requirements put on the photon counting receiver are quite challenging in terms of the long term detection delay stability, wide operation temperature range, extremely high background photon flux and others. Recently, the bread board version of the detector has been constructed and is under extensive test in our labs. The concept and construction will be presented along with the achieved device parameters.

  20. RendezVous sensor for automatic guidance of transfer vehicles to the International Space Station

    NASA Astrophysics Data System (ADS)

    Kolk, Karl-Hermann; Moebius, Bettina G.

    2000-10-01

    Based on a Predevelopment Program, initiated by the European Space Agency, an automatically operating RendezVous Sensor (RVS) is currently developed. This paper describes in more detail the RVS concept emphasizing the electro-optical elements of the sensor.

  1. Space transfer vehicle concepts and requirements. Volume 2, book 2: Appendix

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This appendix describes the work that was performed to define the Lunar transfer vehicle and Lunar excursion vehicle which were part of the 'Report of the 90-Day Study on Human Exploration of the Moon and Mars.' A detailed concept definition of both vehicles including overall dimensions, mass properties, subsystem definition, and operational flight sequences is included.

  2. Timation 3 satellite. [artificial satellite for navigation, space radiation, and time transfer applications

    NASA Technical Reports Server (NTRS)

    Bartholomew, C. A.

    1972-01-01

    The characteristics of the Timation 3 satellite are discussed. A diagram of the basic structure is provide to show the solar panels, navigation and telemetry antennas, gravity gradient booms, and solar cell experiments. The specific application of the satellite for time management or time transfer for navigation purposes is reported. Various measurements and experiments conducted by the satellite are described.

  3. Cryogenic Propellant Storage and Transfer (CPST) Technology Demonstration For Long Duration In-Space Missions

    NASA Technical Reports Server (NTRS)

    Meyer, Michael L.; Motil, Susan M.; Kortes, Trudy F.; Taylor, William J.; McRight, Patrick S.

    2012-01-01

    (1) Store cryogenic propellants in a manner that maximizes their availability for use regardless of mission duration; (2) Efficiently transfer conditioned cryogenic propellant to an engine or tank situated in a microgravity environment; and (3) Accurately monitor and gauge cryogenic propellants situated in a microgravity environment

  4. The Interaction of Study Materials and Spaced Review on Transfer and Relational Learning.

    ERIC Educational Resources Information Center

    Katayama, Andrew D.; Robinson, Daniel H.; Devaney, Thomas; Dubois, Nelson F.

    In two experiments, researchers investigated whether the advantages of studying graphic organizers over outlines for learning text structure and transfer from a chapter-length text are restricted to study sequences that use delayed, rather than immediate, review. In the first of these studies, reported here, 89 undergraduates studied 1 of 3 sets…

  5. Multi-Reflex Propulsion Systems for Space and Air Vehicles and Energy Transfer for Long Distance

    NASA Astrophysics Data System (ADS)

    Bolonkin, A.

    The purpose of this article is to call attention to the revolutionary idea of light multi-reflection. This idea allows the design of new engines, space and air propulsion systems, storage (of a beam and solar energy), transmitters of energy (to millions of kilometers), creation of new weapons, etc. This method and the main innovations were offered by the author in 1983 in the former USSR. Now the author shows in a series of articles the immense possibilities of this idea in many fields of engineering - astronautics, aviation, energy, optics, direct converter of light (laser beam) energy to mechanical energy (light engine), to name a few. This article considers the multi-reflex propulsion systems for space and air vehicles and energy transmitter for long distances in space.

  6. Through-space transfer of chiral information mediated by a plasmonic nanomaterial

    NASA Astrophysics Data System (ADS)

    Ostovar Pour, Saeideh; Rocks, Louise; Faulds, Karen; Graham, Duncan; Parchaňský, Václav; Bouř, Petr; Blanch, Ewan W.

    2015-07-01

    The ability to detect chirality gives stereochemically attuned nanosensors the potential to revolutionize the study of biomolecular processes. Such devices may structurally characterize the mechanisms of protein-ligand binding, the intermediates of amyloidogenic diseases and the effects of phosphorylation and glycosylation. We demonstrate that single nanoparticle plasmonic reporters, or nanotags, can enable a stereochemical response to be transmitted from a chiral analyte to an achiral benzotriazole dye molecule in the vicinity of a plasmon resonance from an achiral metallic nanostructure. The transfer of chirality was verified by the measurement of mirror image surface enhanced resonance Raman optical activity spectra for the two enantiomers of both ribose and tryptophan. Computational modelling confirms these observations and reveals the novel chirality transfer mechanism responsible. This is the first report of colloidal metal nanoparticles in the form of single plasmonic substrates displaying an intrinsic chiral sensitivity once attached to a chiral molecule.

  7. A study of the generation of linear energy transfer spectra for space radiations

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Badavi, Francis F.

    1992-01-01

    The conversion of particle-energy spectra into a linear energy transfer (LET) distribution is a guide in assessing biologically significant components. The mapping of LET to energy is triple valued and can be defined only on open subintervals. A well-defined numerical procedure is found to allow generation of LET spectra on the open subintervals that are integrable in spite of their singular nature.

  8. Space Station based operations and maintenance support to spacecraft, platforms, and orbit transfer vehicle (OTV)

    NASA Technical Reports Server (NTRS)

    Steincamp, J. W.; Mulqueen, J. A.; Maloney, J. W.

    1984-01-01

    The orbital servicing concepts developed for several existing and planned spacecraft are reviewed to illustrate the evolution and capabilities of Shuttle-based support services, and the potential range of future services are categorized by several criteria including transportation systems requirements, supporting facilities and equipment options, and servicing locations. Implications of Space Station-basing the services are described, along with possible implementing systems. In particular, the technique of 'formation flying' by means of which spacecraft may be physically isolated from each other while maintaining reasonable propellant requirements for maneuvers between them is explored by representative examples. OTV mission support is described as an evolutionary augmentation of the basic Space Station services.

  9. Docking Offset Between the Space Shuttle and the International Space Station and Resulting Impacts to the Transfer of Attitude Reference and Control

    NASA Technical Reports Server (NTRS)

    Helms, W. Jason; Pohlkamp, Kara M.

    2011-01-01

    The Space Shuttle does not dock at an exact 90 degrees to the International Space Station (ISS) x-body axis. This offset from 90 degrees, along with error sources within their respective attitude knowledge, causes the two vehicles to never completely agree on their attitude, even though they operate as a single, mated stack while docked. The docking offset can be measured in flight when both vehicles have good attitude reference and is a critical component in calculations to transfer attitude reference from one vehicle to another. This paper will describe how the docking offset and attitude reference errors between both vehicles are measured and how this information would be used to recover Shuttle attitude reference from ISS in the event of multiple failures. During STS-117, ISS on-board Guidance, Navigation and Control (GNC) computers began having problems and after several continuous restarts, the systems failed. The failure took the ability for ISS to maintain attitude knowledge. This paper will also demonstrate how with knowledge of the docking offset, the contingency procedure to recover Shuttle attitude reference from ISS was reversed in order to provide ISS an attitude reference from Shuttle. Finally, this paper will show how knowledge of the docking offset can be used to speed up attitude control handovers from Shuttle to ISS momentum management. By taking into account the docking offset, Shuttle can be commanded to hold a more precise attitude which better agrees with the ISS commanded attitude such that start up transients with the ISS momentum management controllers are reduced. By reducing start-up transients, attitude control can be transferred from Shuttle to ISS without the use of ISS thrusters saving precious on-board propellant, crew time and minimizing loads placed upon the mated stack.

  10. A study of LC-39 cryogenic systems. Part 1: A study of the vacuum insulated transfer lines at Kennedy Space Center. Part 2: Cooldown pressure surges

    NASA Technical Reports Server (NTRS)

    Ludtke, P. R.; Voth, R. O.

    1971-01-01

    The vacuum liquid hydrogen and liquid oxygen transfer lines at Kennedy Space Center were studied to evaluate the feasibility of using a condensing gas such as CO2 inside the vacuum spaces to achieve a condensing-vacuum. The study indicates that at ambient temperature, a maximum vacuum hyphen space pressure of 4000 microns is acceptable for the LH2 transfer lines. In addition, the cooldown procedures for the 14-inch cross-country liquid oxygen line was studied using a simplified mathematical model. Preliminary cooldown times are presented for various heat leak rates to the line and for two vent configurations.

  11. Large File Transfers from Space Using Multiple Ground Terminals and Delay-Tolerant Networking

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Paulsen, Phillip; Stewart, Dave; Eddy, Wesley; McKim, James; Taylor, John; Lynch, Scott; Heberle, Jay; Northam, James; Jackson, Chris; Wood, Lloyd

    2010-01-01

    We use Delay-Tolerant Networking (DTN) to break control loops between space-ground communication links and ground-ground communication links to increase overall file delivery efficiency, as well as to enable large files to be proactively fragmented and received across multiple ground stations. DTN proactive fragmentation and reactive fragmentation were demonstrated from the UK-DMC satellite using two independent ground stations. The files were reassembled at a bundle agent, located at Glenn Research Center in Cleveland Ohio. The first space-based demonstration of this occurred on September 30 and October 1, 2009. This paper details those experiments. Communication, delay-tolerant networking, DTN, satellite, Internet, protocols, bundle, IP, TCP.

  12. Performance Characterization of Digital Optical Data Transfer Systems for Use in the Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Reed, Robert A.; Ladbury, Ray L.; Day, John H. (Technical Monitor)

    2000-01-01

    Radiation effects in photonic and microelectronic components can impact the performance of high-speed digital optical data link in a variety of ways. This segment of the short course focuses on radiation effects in digital optical data links operating in the MHz to GHz regime. (Some of the information is applicable to frequencies above and below this regime) The three basic component level effects that should be considered are Total Ionizing Dose (TID), Displacement Damage Dose (DDD) and Single Event Effects (SEE). In some cases the system performance degradation can be quantified from component level tests, while in others a more holistic characterization approach must be taken. In Section 2.0 of this segment of the Short Course we will give a brief overview of the space radiation environment follow by a summary of the basic space radiation effects important for microelectronics and photonics listed above. The last part of this section will give an example of a typical mission radiation environment requirements. Section 3.0 gives an overview of intra-satellite digital optical data link systems. It contains a discussion of the digital optical data link and it's components. Also, we discuss some of the important system performance metrics that are impacted by radiation effects degradation of optical and optoelectronic component performance. Section 4.0 discusses radiation effects in optical and optoelectronic components. While each component effect will be discussed, the focus of this section is on degradation of passive optical components and SEE in photodiodes (other mechanisms are covered in segment II of this short course entitled "Photonic Devices with Complex and Multiple Failure Modes"). Section 5.0 will focus on optical data link system response to the space radiation environment. System level SEE ground testing will be discussed. Then we give a discussion of system level assessment of data link performance when operating in the space radiation environment.

  13. Thermal-Flow Code for Modeling Gas Dynamics and Heat Transfer in Space Shuttle Solid Rocket Motor Joints

    NASA Technical Reports Server (NTRS)

    Wang, Qunzhen; Mathias, Edward C.; Heman, Joe R.; Smith, Cory W.

    2000-01-01

    A new, thermal-flow simulation code, called SFLOW. has been developed to model the gas dynamics, heat transfer, as well as O-ring and flow path erosion inside the space shuttle solid rocket motor joints by combining SINDA/Glo, a commercial thermal analyzer. and SHARPO, a general-purpose CFD code developed at Thiokol Propulsion. SHARP was modified so that friction, heat transfer, mass addition, as well as minor losses in one-dimensional flow can be taken into account. The pressure, temperature and velocity of the combustion gas in the leak paths are calculated in SHARP by solving the time-dependent Navier-Stokes equations while the heat conduction in the solid is modeled by SINDA/G. The two codes are coupled by the heat flux at the solid-gas interface. A few test cases are presented and the results from SFLOW agree very well with the exact solutions or experimental data. These cases include Fanno flow where friction is important, Rayleigh flow where heat transfer between gas and solid is important, flow with mass addition due to the erosion of the solid wall, a transient volume venting process, as well as some transient one-dimensional flows with analytical solutions. In addition, SFLOW is applied to model the RSRM nozzle joint 4 subscale hot-flow tests and the predicted pressures, temperatures (both gas and solid), and O-ring erosions agree well with the experimental data. It was also found that the heat transfer between gas and solid has a major effect on the pressures and temperatures of the fill bottles in the RSRM nozzle joint 4 configuration No. 8 test.

  14. A Computational Fluid Dynamic and Heat Transfer Model for Gaseous Core and Gas Cooled Space Power and Propulsion Reactors

    NASA Technical Reports Server (NTRS)

    Anghaie, S.; Chen, G.

    1996-01-01

    A computational model based on the axisymmetric, thin-layer Navier-Stokes equations is developed to predict the convective, radiation and conductive heat transfer in high temperature space nuclear reactors. An implicit-explicit, finite volume, MacCormack method in conjunction with the Gauss-Seidel line iteration procedure is utilized to solve the thermal and fluid governing equations. Simulation of coolant and propellant flows in these reactors involves the subsonic and supersonic flows of hydrogen, helium and uranium tetrafluoride under variable boundary conditions. An enthalpy-rebalancing scheme is developed and implemented to enhance and accelerate the rate of convergence when a wall heat flux boundary condition is used. The model also incorporated the Baldwin and Lomax two-layer algebraic turbulence scheme for the calculation of the turbulent kinetic energy and eddy diffusivity of energy. The Rosseland diffusion approximation is used to simulate the radiative energy transfer in the optically thick environment of gas core reactors. The computational model is benchmarked with experimental data on flow separation angle and drag force acting on a suspended sphere in a cylindrical tube. The heat transfer is validated by comparing the computed results with the standard heat transfer correlations predictions. The model is used to simulate flow and heat transfer under a variety of design conditions. The effect of internal heat generation on the heat transfer in the gas core reactors is examined for a variety of power densities, 100 W/cc, 500 W/cc and 1000 W/cc. The maximum temperature, corresponding with the heat generation rates, are 2150 K, 2750 K and 3550 K, respectively. This analysis shows that the maximum temperature is strongly dependent on the value of heat generation rate. It also indicates that a heat generation rate higher than 1000 W/cc is necessary to maintain the gas temperature at about 3500 K, which is typical design temperature required to achieve high

  15. [MEASUREMENT OF SPACE RADIATION DOSES AND LINEAR ENERGY TRANSFER SPECTRA INSIDE BIOLOGICAL SATELLITE BION-M1].

    PubMed

    Inozemtsev, K O; Kushin, V V; Tolochek, R V; Shurshakov, V A

    2015-01-01

    The paper presents the results of measuring biologically significant characteristics of space radiation (spectra of linear energy transfer (LET), absorbed and equivalent doses and averaged quality factors) inside the descend capsule of biosatellite Bion-M1 in space experiment Bioradiation. Measurements combined the use of thermoluminescent detectors DTG-4 (TDL) and solid state nuclear track detectors CR-39 (Tastrak) (SSNTD). Differential and integral LET spectra of high-LET space radiation were determined in 4 points inside spacecraft using passive detectors assembles (PDA). Total absorbed dose rates for PDA boxes No 1-4 made up 2.4 ± 0.2; 1.1 ± 0.1; 1.6 ± 0.2; 2.0 ± 0.1 mGy/d respectively, whereas total equivalent dose rates estimated based on ICRP Publication 60 recommendations made up 3.4 ± 0.2; 2.0 ± 0.1; 2.6 ± 0.2; 3.1 ± 0.1 mSv/d respectively. Values of the averaged quality factor for different PDSs were in the range between 1.4 and 1.8. PMID:26087582

  16. Response of Silicon-Based Linear Energy Transfer Spectrometers: Implication for Radiation Risk Assessment in Space Flights

    NASA Technical Reports Server (NTRS)

    Badhwar, G. D.; O'Neill, P. M.

    2001-01-01

    There is considerable interest in developing silicon-based telescopes because of their compactness and low power requirements. Three such telescopes have been flown on board the Space Shuttle to measure the linear energy transfer spectra of trapped, galactic cosmic ray, and solar energetic particles. Dosimeters based on single silicon detectors have also been flown on the Mir orbital station. A comparison of the absorbed dose and radiation quality factors calculated from these telescopes with that estimated from measurements made with a tissue equivalent proportional counter show differences which need to be fully understood if these telescopes are to be used for astronaut radiation risk assessments. Instrument performance is complicated by a variety of factors. A Monte Carlo-based technique was developed to model the behavior of both single element detectors in a proton beam, and the performance of a two-element, wide-angle telescope, in the trapped belt proton field inside the Space Shuttle. The technique is based on: (1) radiation transport intranuclear-evaporation model that takes into account the charge and angular distribution of target fragments, (2) Landau-Vavilov distribution of energy deposition allowing for electron escape, (3) true detector geometry of the telescope, (4) coincidence and discriminator settings, (5) spacecraft shielding geometry, and (6) the external space radiation environment, including albedo protons. The value of such detailed modeling and its implications in astronaut risk assessment is addressed. c2001 Elsevier Science B.V. All rights reserved.

  17. Response of silicon-based linear energy transfer spectrometers: implication for radiation risk assessment in space flights.

    PubMed

    Badhwar, G D; O'Neill, P M

    2001-07-11

    There is considerable interest in developing silicon-based telescopes because of their compactness and low power requirements. Three such telescopes have been flown on board the Space Shuttle to measure the linear energy transfer spectra of trapped, galactic cosmic ray, and solar energetic particles. Dosimeters based on single silicon detectors have also been flown on the Mir orbital station. A comparison of the absorbed dose and radiation quality factors calculated from these telescopes with that estimated from measurements made with a tissue equivalent proportional counter show differences which need to be fully understood if these telescopes are to be used for astronaut radiation risk assessments. Instrument performance is complicated by a variety of factors. A Monte Carlo-based technique was developed to model the behavior of both single element detectors in a proton beam, and the performance of a two-element, wide-angle telescope, in the trapped belt proton field inside the Space Shuttle. The technique is based on: (1) radiation transport intranuclear-evaporation model that takes into account the charge and angular distribution of target fragments, (2) Landau-Vavilov distribution of energy deposition allowing for electron escape, (3) true detector geometry of the telescope, (4) coincidence and discriminator settings, (5) spacecraft shielding geometry, and (6) the external space radiation environment, including albedo protons. The value of such detailed modeling and its implications in astronaut risk assessment is addressed. PMID:11858255

  18. The Electric Propulsion Space Experiment (ESEX)-A demonstration of high power arcjets for orbit transfer applications

    NASA Astrophysics Data System (ADS)

    Bromaghim, D. R.; Salasovich, R. M.; Leduc, J. R.; Johnson, L. K.

    1998-01-01

    The Electric Propulsion Space Experiment (ESEX) is a high power (30 kW) ammonia arcjet space demonstration sponsored by the Propulsion Directorate of the Phillips Laboratory with TRW as the prime contractor. ESEX is one of nine experiments being launched in early 1998 on board the Advanced Research and Global Observation Satellite (ARGOS). ESEX will demonstrate the feasibility of using a high power arcjet for orbit transfer. ESEX is instrumented with various sensors to address all of the expected interactions with ARGOS including electromagnetic interference, contamination, and radiated thermal loading. The performance of the arcjet will also be measured using ground tracking, an on-board GPS receiver, and on-board accelerometer. In addition to the performance and spacecraft interaction studies, ground-based spectroscopic and radiometric measurements will be performed to observe plume species as well as determine the effect of the arcjet firing on the space environment. ESEX is currently undergoing integrated testing with the spacecraft bus and the eight other experiments to verify the full operability of ARGOS while on-orbit. These tests include basic functionality of the system in addition to the normal suite of environmental tests including electromagnetic interference and compatibility, acoustic and pyroshock testing, and thermal vacuum tests.

  19. Response of silicon-based linear energy transfer spectrometers: implication for radiation risk assessment in space flights

    NASA Astrophysics Data System (ADS)

    Badhwar, G. D.; O'Neill, P. M.

    2001-07-01

    There is considerable interest in developing silicon-based telescopes because of their compactness and low power requirements. Three such telescopes have been flown on board the Space Shuttle to measure the linear energy transfer spectra of trapped, galactic cosmic ray, and solar energetic particles. Dosimeters based on single silicon detectors have also been flown on the Mir orbital station. A comparison of the absorbed dose and radiation quality factors calculated from these telescopes with that estimated from measurements made with a tissue equivalent proportional counter show differences which need to be fully understood if these telescopes are to be used for astronaut radiation risk assessments. Instrument performance is complicated by a variety of factors. A Monte Carlo-based technique was developed to model the behavior of both single element detectors in a proton beam, and the performance of a two-element, wide-angle telescope, in the trapped belt proton field inside the Space Shuttle. The technique is based on: (1) radiation transport intranuclear-evaporation model that takes into account the charge and angular distribution of target fragments, (2) Landau-Vavilov distribution of energy deposition allowing for electron escape, (3) true detector geometry of the telescope, (4) coincidence and discriminator settings, (5) spacecraft shielding geometry, and (6) the external space radiation environment, including albedo protons. The value of such detailed modeling and its implications in astronaut risk assessment is addressed.

  20. Technology transfer from space to earth - The NASA Firefighter's Breathing System

    NASA Technical Reports Server (NTRS)

    Mclaughlan, P. B.; Anuskiewicz, T.; Keune, F. A.

    1976-01-01

    Responding to the recent demand of fire services for a better equipment, NASA has prepared two improved versions of Firefighter's Breathing System (FBS) by taking advantage of the spacesuit design. In the new FBS, the conventional oxygen tube is replaced by a 40% lighter air tube with twice as much pressure. The load is attached to a wide waist belt and distributed on the hips instead of the shoulder, thus making it easier to carry. The two versions of the FBS are essentially the same, the only difference being the capacities of the air tubes. Also the face mask used is smaller, lighter and provides better vision and mobility. The FBS had a notable impact, with the fire departments reporting improved efficiency. Unlike other technology transfer cases, the FBS concept is commercially successful in finding diverse fields of application.

  1. Thermodynamic analysis and subscale modeling of space-based orbit transfer vehicle cryogenic propellant resupply

    NASA Technical Reports Server (NTRS)

    Defelice, David M.; Aydelott, John C.

    1987-01-01

    The resupply of the cryogenic propellants is an enabling technology for spacebased orbit transfer vehicles. As part of the NASA Lewis ongoing efforts in microgravity fluid management, thermodynamic analysis and subscale modeling techniques were developed to support an on-orbit test bed for cryogenic fluid management technologies. Analytical results have shown that subscale experimental modeling of liquid resupply can be used to validate analytical models when the appropriate target temperature is selected to relate the model to its prototype system. Further analyses were used to develop a thermodynamic model of the tank chilldown process which is required prior to the no-vent fill operation. These efforts were incorporated into two FORTRAN programs which were used to present preliminary analyticl results.

  2. A modified Finite Element-Transfer Matrix for control design of space structures

    NASA Technical Reports Server (NTRS)

    Tan, T.-M.; Yousuff, A.; Bahar, L. Y.; Konstandinidis, M.

    1990-01-01

    The Finite Element-Transfer Matrix (FETM) method was developed for reducing the computational efforts involved in structural analysis. While being widely used by structural analysts, this method does, however, have certain limitations, particularly when used for the control design of large flexible structures. In this paper, a new formulation based on the FETM method is presented. The new method effectively overcomes the limitations in the original FETM method, and also allows an easy construction of reduced models that are tailored for the control design. Other advantages of this new method include the ability to extract open loop frequencies and mode shapes with less computation, and simplification of the design procedures for output feedback, constrained compensation, and decentralized control. The development of this new method and the procedures for generating reduced models using this method are described in detail and the role of the reduced models in control design is discussed through an illustrative example.

  3. Orbital angular momentum (OAM) multiplexing in free-space optical data transfer

    NASA Astrophysics Data System (ADS)

    Lin, Jiao; Yuan, Xiao-Cong; Tao, Shaohua

    2006-08-01

    In the optical wireless communication systems proposed by Gibson, et al, the information is encoded as states of orbital angular momentum (OAM) of light and the transmitter unit can produce laser beam with single OAM-state in a time-slot. Recently we have proved that it is possible to generate multiple OAM-states simultaneously by single spatial light modulator. This method is adopted in our free-space optical wireless communication system and these OAM-states can be detected in the receiving unit by a computer-generated hologram. Hence, the transmission capacity is enhanced significantly without increasing the complexity of system.

  4. Transfer of perceptual-motor training and the space adaptation syndrome

    NASA Technical Reports Server (NTRS)

    Kennedy, R. S.; Berbaum, K. S.; Williams, M. C.; Brannan, J.; Welch, R. B.

    1987-01-01

    Perceptual cue conflict may be the basis for the symptoms which are experienced by space travelers in microgravity conditions. Recovery has been suggested to take place after perceptual modification or reinterpretation. To elucidate this process, 10 subjects who repeatedly experienced a visual/vestibular conflict over trials and days, were tested in a similar but not identical perceptual situation (pseudo-Coriolis) to determine whether any savings in perceptual adaptation had occurred as compared to an unpracticed control group (N = 40). The practiced subjects experienced lessening dizziness and ataxia within and over sessions.

  5. The effects of inlet turbulence and rotor/stator interactions on the aerodynamics and heat transfer of a large-scale rotating turbine model. Volume 3: Heat transfer data tabulation 65 percent axial spacing

    NASA Technical Reports Server (NTRS)

    Dring, R. P.; Blair, M. F.; Joslyn, H. D.

    1986-01-01

    This is Volume 3 - Heat Transfer Data Tabulation (65 percent Axial Spacing) of a combined experimental and analytical program which was conducted to examine the effects of inlet turbulence on airfoil heat transfer. The experimental portion of the study was conducted in a large-scale (approximately 5X engine), ambient temperature, rotating turbine model configured in both single stage and stage-and-a-half arrangements. Heat transfer measurements were obtained using low-conductivity airfoils with miniature thermocouples welded to a thin, electrically heated surface skin. Heat transfer data were acquired for various combinations of low or high inlet turbulence intensity, flow coefficient, first-stator/rotor axial spacing, Reynolds number and relative circumferential position of the first and second stators.

  6. Energy efficient rateless codes for high speed data transfer over free space optical channels

    NASA Astrophysics Data System (ADS)

    Prakash, Geetha; Kulkarni, Muralidhar; Acharya, U. S.

    2015-03-01

    Terrestrial Free Space Optical (FSO) links transmit information by using the atmosphere (free space) as a medium. In this paper, we have investigated the use of Luby Transform (LT) codes as a means to mitigate the effects of data corruption induced by imperfect channel which usually takes the form of lost or corrupted packets. LT codes, which are a class of Fountain codes, can be used independent of the channel rate and as many code words as required can be generated to recover all the message bits irrespective of the channel performance. Achieving error free high data rates with limited energy resources is possible with FSO systems if error correction codes with minimal overheads on the power can be used. We also employ a combination of Binary Phase Shift Keying (BPSK) with provision for modification of threshold and optimized LT codes with belief propagation for decoding. These techniques provide additional protection even under strong turbulence regimes. Automatic Repeat Request (ARQ) is another method of improving link reliability. Performance of ARQ is limited by the number of retransmissions and the corresponding time delay. We prove through theoretical computations and simulations that LT codes consume less energy per bit. We validate the feasibility of using energy efficient LT codes over ARQ for FSO links to be used in optical wireless sensor networks within the eye safety limits.

  7. A discrete pathway for the transfer of intermembrane space proteins across the outer membrane of mitochondria.

    PubMed

    Gornicka, Agnieszka; Bragoszewski, Piotr; Chroscicki, Piotr; Wenz, Lena-Sophie; Schulz, Christian; Rehling, Peter; Chacinska, Agnieszka

    2014-12-15

    Mitochondrial proteins are synthesized on cytosolic ribosomes and imported into mitochondria with the help of protein translocases. For the majority of precursor proteins, the role of the translocase of the outer membrane (TOM) and mechanisms of their transport across the outer mitochondrial membrane are well recognized. However, little is known about the mode of membrane translocation for proteins that are targeted to the intermembrane space via the redox-driven mitochondrial intermembrane space import and assembly (MIA) pathway. On the basis of the results obtained from an in organello competition import assay, we hypothesized that MIA-dependent precursor proteins use an alternative pathway to cross the outer mitochondrial membrane. Here we demonstrate that this alternative pathway involves the protein channel formed by Tom40. We sought a translocation intermediate by expressing tagged versions of MIA-dependent proteins in vivo. We identified a transient interaction between our model substrates and Tom40. Of interest, outer membrane translocation did not directly involve other core components of the TOM complex, including Tom22. Thus MIA-dependent proteins take another route across the outer mitochondrial membrane that involves Tom40 in a form that is different from the canonical TOM complex. PMID:25318675

  8. A discrete pathway for the transfer of intermembrane space proteins across the outer membrane of mitochondria

    PubMed Central

    Gornicka, Agnieszka; Bragoszewski, Piotr; Chroscicki, Piotr; Wenz, Lena-Sophie; Schulz, Christian; Rehling, Peter; Chacinska, Agnieszka

    2014-01-01

    Mitochondrial proteins are synthesized on cytosolic ribosomes and imported into mitochondria with the help of protein translocases. For the majority of precursor proteins, the role of the translocase of the outer membrane (TOM) and mechanisms of their transport across the outer mitochondrial membrane are well recognized. However, little is known about the mode of membrane translocation for proteins that are targeted to the intermembrane space via the redox-driven mitochondrial intermembrane space import and assembly (MIA) pathway. On the basis of the results obtained from an in organello competition import assay, we hypothesized that MIA-dependent precursor proteins use an alternative pathway to cross the outer mitochondrial membrane. Here we demonstrate that this alternative pathway involves the protein channel formed by Tom40. We sought a translocation intermediate by expressing tagged versions of MIA-dependent proteins in vivo. We identified a transient interaction between our model substrates and Tom40. Of interest, outer membrane translocation did not directly involve other core components of the TOM complex, including Tom22. Thus MIA-dependent proteins take another route across the outer mitochondrial membrane that involves Tom40 in a form that is different from the canonical TOM complex. PMID:25318675

  9. Radiative transfer to space through a precipitating cloud at multiple microwave frequencies. III - Influence of large ice particles

    NASA Technical Reports Server (NTRS)

    Smith, Eric A.; Mugnai, Alberto

    1989-01-01

    The time-dependent influence of large ice particles on the brightness temperatures, T(B)s, that would be observed from space above severe thunderstorms is investigated using a vertically and angularly detailed plane-parallel microwave radiative transfer model. The impact of large ice particles on passive microwave T(B)s over an evolving model rain cloud was examined at ten separate frequencies in the EHF/SHF spectrum. It is shown that the frequency-dependent vertically distributed generalized emission/scattering weighting functions, introduced in this simulation to vertically resolve the contributions by individual cloud and precipitation layers to the T(B)s, can be used to identify the specific layers responsible for regulating the magnitude of top-of-atmoshere T(B)s.

  10. Low thrust chemical propulsion for orbit transfer of large space structures

    NASA Technical Reports Server (NTRS)

    Shoji, J. M.

    1981-01-01

    For transporting Large Space Structures (LSS) from Low Earth Orbit (LEO) to Geosynchronous Equatorial Orbit (GEO), a variety of low thrust engine cycles have been evaluated for oxygen/hydrogen and oxygen/hydrocarbon propellants. The engine cycles included conventional propellant turbine drives (gas generator, expander, and staged-combustion cycles), turboalternator/electric motor pump drive, and fuel-cell/electric motor pump drive, as well as pressure-fed engines. The thrust chamber cooling limits and the engine cycle limits were established for a range of thrust levels. The candidate engine cycles were analyzed, screened, rated, and two engine cycle/configurations were selected for preliminary engine design. Preliminary engine designs for these two engines were formulated and engine design layouts prepared and parametric engine data generated.

  11. Transfer of electrical space charge from corona between ground and thundercloud: Measurements and modeling

    NASA Technical Reports Server (NTRS)

    Soula, Serge

    1994-01-01

    The evolution of the vertical electric field profile deduced from simultaneous field measurements at several levels below a thundercloud shows the development of a space charge layer at least up to 600 m. The average charge density in the whole layer from 0 m to 600 m can reach about 1 nC m(exp -3). The ions are generated at the ground by corona effect and the production rate is evaluated with a new method from the comparison of field evolutions at the ground and at altitude after a lightning flash. The modeling of the relevant processes shows tht ground corona accounts for the observed field evolutions and that the aerosol particles concentration has a very large effect on the evolution of corona ions. However, with a realistic value for this concentration a large amount of ground corona ions reach the level of 600 m.

  12. Space network scheduling benchmark: A proof-of-concept process for technology transfer

    NASA Technical Reports Server (NTRS)

    Moe, Karen; Happell, Nadine; Hayden, B. J.; Barclay, Cathy

    1993-01-01

    This paper describes a detailed proof-of-concept activity to evaluate flexible scheduling technology as implemented in the Request Oriented Scheduling Engine (ROSE) and applied to Space Network (SN) scheduling. The criteria developed for an operational evaluation of a reusable scheduling system is addressed including a methodology to prove that the proposed system performs at least as well as the current system in function and performance. The improvement of the new technology must be demonstrated and evaluated against the cost of making changes. Finally, there is a need to show significant improvement in SN operational procedures. Successful completion of a proof-of-concept would eventually lead to an operational concept and implementation transition plan, which is outside the scope of this paper. However, a high-fidelity benchmark using actual SN scheduling requests has been designed to test the ROSE scheduling tool. The benchmark evaluation methodology, scheduling data, and preliminary results are described.

  13. Transferring Knowledge from a Bird's-Eye View - Earth Observation and Space Travels in Schools

    NASA Astrophysics Data System (ADS)

    Rienow, Andreas; Hodam, Henryk; Menz, Gunter; Voß, Kerstin

    2014-05-01

    In spring 2014, four commercial cameras will be transported by a Dragon spacecraft to the International Space Station (ISS) and mounted to the ESA Columbus laboratory. The cameras will deliver live earth observation data from different angles. The "Columbus-Eye"* project aims at distributing the video and image data produced by those cameras through a web portal. It should primary serve as learning portal for pupils comprising teaching material around the ISS earth observation imagery. The pupils should be motivated to work with the images in order to learn about curriculum relevant topics of natural sciences. The material will be prepared based on the experiences of the FIS* (German abbreviation for "Remote Sensing in Schools") project and its learning portal. Recognizing that in-depth use of satellite imagery can only be achieved by the means of computer aided learning methods, a sizeable number of e-Learning contents in German and English have been created throughout the last 5 years since FIS' kickoff. The talk presents the educational valorization of remote sensing data as well as their interactive implementation for teachers and pupils in both learning portals. It will be shown which possibilities the topic of remote sensing holds ready for teaching the regular curricula of Geography, Biology, Physics, Math and Informatics. Beside the sequenced implementation into digital and interactive teaching units, examples of a richly illustrated encyclopedia as well as easy-to-use image processing tools are given. The presentation finally addresses the question of how synergies of space travels can be used to enhance the fascination of earth observation imagery in the light of problem-based learning in everyday school lessons.

  14. Building America Case Study: Air Leakage and Air Transfer Between Garage and Living Space, Waldorf, Maryland (Fact Sheet)

    SciTech Connect

    Not Available

    2014-11-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the Baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  15. Survivability of bare, individual Bacillus subtilis spores to high-velocity surface impact: Implications for microbial transfer through space

    NASA Astrophysics Data System (ADS)

    Barney, Brandon L.; Pratt, Sara N.; Austin, Daniel E.

    2016-06-01

    Laboratory experiments show that endospores of Bacillus subtilis survive impact against a solid surface at velocities as high as 299 ±28 m/s. During impact, spores experience and survive accelerations of at least 1010 m/s2. The spores were introduced into a vacuum chamber using an electrospray source and accelerated to a narrow velocity distribution by entrainment in a differentially pumped gas flow. Different velocity ranges were studied by modifying the gas flow parameters. The spores were electrically charged, allowing direct measurement of the velocity of each spore as it passed through an image charge detector prior to surface impact. Spores impacted a glass surface and were collected for subsequent analysis by culturing. Most spores survived impact at all measured velocities. These experiments differ fundamentally from other studies that show either shock or impact survivability of bacteria embedded within or on the surface of a projectile. Bacteria in the present experiments undergo a single interaction with a solid surface at the full impact velocity, in the absence of any other effects such as cushioning due to microbe agglomerations, deceleration due to air or vapor, or transfer of impact shock through solid or liquid media. During these full-velocity impact events, the spores experience extremely high decelerations. This study is the first reported instance of accelerations of this magnitude experienced during a bacteria impact event. These results are discussed in the context of potential transfer of viable microbes in space and other scenarios involving surface impacts at high velocities.

  16. Space transfer vehicle concepts and requirements. Volume 4: Summary of special studies

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Our final report for Phase 1 addressed the future space transportation needs and requirements based on the current assets, at the time, and their evolution through technology/advanced development using a path and schedule that supported the world leadership role of the United States in a responsible and realistic financial forecast. Always, and foremost, the recommendations placed high values on the safety and success of missions both manned and unmanned through a total quality management philosophy at Martin Marietta. The second phase of the STV contract involved the use of Technical Directives (TD) to provide short-term support for specialized tasks as required by the COTR. Three of these tasks were performed in parallel with Phase 1. These tasks were the Liquid Acquisition Experiment (LACE), Liquid Reorientation Experiment (LIRE), and Expert System for Design, Operation, and Technology Studies (ESDOTS). The results of these TD's were reported in conjunction with the Phase 1 Final Report. Cost analysis of existing launch systems has demonstrated a need for a new upper stage that will increase America's competitiveness in the global launch services market. To provide a growth path of future exploration class STV's, near-term low-cost upper stages featuring modularity, portability, scalability, and evolvability must be developed. These recommendations define a program that: leverages ongoing activities to establish a new development environment, develop technologies that benefit the entire life cycle of a system, and result in a scalable hardware platform that provides a growth path to future upper stages.

  17. Space transfer vehicle concepts and requirements. Volume 4: Summary of special studies

    NASA Astrophysics Data System (ADS)

    1993-09-01

    Our final report for Phase 1 addressed the future space transportation needs and requirements based on the current assets, at the time, and their evolution through technology/advanced development using a path and schedule that supported the world leadership role of the United States in a responsible and realistic financial forecast. Always, and foremost, the recommendations placed high values on the safety and success of missions both manned and unmanned through a total quality management philosophy at Martin Marietta. The second phase of the STV contract involved the use of Technical Directives (TD) to provide short-term support for specialized tasks as required by the COTR. Three of these tasks were performed in parallel with Phase 1. These tasks were the Liquid Acquisition Experiment (LACE), Liquid Reorientation Experiment (LIRE), and Expert System for Design, Operation, and Technology Studies (ESDOTS). The results of these TD's were reported in conjunction with the Phase 1 Final Report. Cost analysis of existing launch systems has demonstrated a need for a new upper stage that will increase America's competitiveness in the global launch services market. To provide a growth path of future exploration class STV's, near-term low-cost upper stages featuring modularity, portability, scalability, and evolvability must be developed. These recommendations define a program that: leverages ongoing activities to establish a new development environment, develop technologies that benefit the entire life cycle of a system, and result in a scalable hardware platform that provides a growth path to future upper stages.

  18. Evaluation of reusable surface insulation for space shuttle over a range of heat-transfer rate and surface temperature

    NASA Technical Reports Server (NTRS)

    Chapman, A. J.

    1973-01-01

    Reusable surface insulation materials, which were developed as heat shields for the space shuttle, were tested over a range of conditions including heat-transfer rates between 160 and 620 kW/sq m. The lowest of these heating rates was in a range predicted for the space shuttle during reentry, and the highest was more than twice the predicted entry heating on shuttle areas where reusable surface insulation would be used. Individual specimens were tested repeatedly at increasingly severe conditions to determine the maximum heating rate and temperature capability. A silica-base material experienced only minimal degradation during repeated tests which included conditions twice as severe as predicted shuttle entry and withstood cumulative exposures three times longer than the best mullite material. Mullite-base materials cracked and experienced incipient melting at conditions within the range predicted for shuttle entry. Neither silica nor mullite materials consistently survived the test series with unbroken waterproof surfaces. Surface temperatures for a silica and a mullite material followed a trend expected for noncatalytic surfaces, whereas surface temperatures for a second mullite material appeared to follow a trend expected for a catalytic surface.

  19. The Hybrid Propellant Module (HPM): A New Concept for Space Transfer in the Earth's Neighborhood and Beyond

    NASA Technical Reports Server (NTRS)

    Mankins, John C.; Mazanek, Daniel D.

    2001-01-01

    The safe, affordable and effective transfer of ever-larger payloads and eventually personnel beyond Low Earth Orbit (LEO) is a major challenge facing future commercial development and human exploration of space. Without reusable systems, sustained exploration or large scale development beyond LEO appears to be economically non-viable. However, reusable systems must be capable of both good fuel efficiency and "high utilization of capacity", or else economic costs will remain unacceptably high. Various options exist that can provide high fuel efficiency - for example, Solar Electric Propulsion Systems (SEPS) - but only at the cost of low thrust and concomitant long transit times. Chemical propulsion systems offer the potential for high thrust and short transit times - including both cryogenic and non-cryogenic options - but only at the cost of relatively low specific impulse (Isp). Nuclear thermal propulsion systems offer relatively good thrust-to-weight and Isp - but involve public concerns that may be insurmountable for all except the most-critical of public purposes. Fixed infrastructures have been suggested as one approach to solving this challenge; for example, rotating tether approaches. However, these systems tend to suffer from high initial costs or unacceptable operational constraints. A new concept has been identified - the Hybrid Propellant Module (HPM) - that integrates the best features of both chemical and solar electric transportation architectures. The HPM approach appears to hold promise of solving the issues associated with other approaches, opening a new family of capabilities for future space exploration and development of near-Earth space and beyond. This paper provides a summary overview of the challenge of Earth neighborhood transportation and discusses how various systems concepts might be applied to meet the needs of these architectures. The paper describes a new approach, the HPM, and illustrates the application of the concept for a typical

  20. Demonstration of pattern transfer into sub-100 nm polysilicon line/space features patterned with extreme ultraviolet lithography

    SciTech Connect

    Cardinale, G. F.; Henderson, C. C.; Goldsmith, J. E. M.; Mangat, P. J. S.; Cobb, J.; Hector, S. D.

    1999-11-01

    In two separate experiments, we have successfully demonstrated the transfer of dense- and loose-pitch line/space (L/S) photoresist features, patterned with extreme ultraviolet (EUV) lithography, into an underlying hard mask material. In both experiments, a deep-UV photoresist ({approx}90 nm thick) was spin cast in bilayer format onto a hard mask (50-90 nm thick) and was subsequently exposed to EUV radiation using a 10x reduction EUV exposure system. The EUV reticle was fabricated at Motorola (Tempe, AZ) using a subtractive process with Ta-based absorbers on Mo/Si multilayer mask blanks. In the first set of experiments, following the EUV exposures, the L/S patterns were transferred first into a SiO{sub 2} hard mask (60 nm thick) using a reactive ion etch (RIE), and then into polysilicon (350 nm thick) using a triode-coupled plasma RIE etcher at the University of California, Berkeley, microfabrication facilities. The latter etch process, which produced steep (>85 degree sign ) sidewalls, employed a HBr/Cl chemistry with a large (>10:1) etch selectivity of polysilicon to silicon dioxide. In the second set of experiments, hard mask films of SiON (50 nm thick) and SiO{sub 2} (87 nm thick) were used. A RIE was performed at Motorola using a halogen gas chemistry that resulted in a hard mask-to-photoresist etch selectivity >3:1 and sidewall profile angles {>=}85 degree sign . Line edge roughness (LER) and linewidth critical dimension (CD) measurements were performed using Sandia's GORA(c) CD digital image analysis software. Low LER values (6-9 nm, 3{sigma}, one side) and good CD linearity (better than 10%) were demonstrated for the final pattern-transferred dense polysilicon L/S features from 80 to 175 nm. In addition, pattern transfer (into polysilicon) of loose-pitch (1:2) L/S features with CDs{>=}60 nm was demonstrated. (c) 1999 American Vacuum Society.

  1. Space benefits: The secondary application of aerospace technology in other sectors of the economy. [(information dissemination and technology transfer from NASA programs)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Space Benefits is a publication that has been prepared for the NASA Technology Utilization Office by the Denver Research Institute's Program for Transfer Research and Impact Studies, to provide the Agency with accurate, convenient, and integrated resource information on the transfer of aerospace technology to other sectors of the U.S. economy. The technological innovations derived from NASA space programs and their current applications in the following areas are considered: (1) manufacturing consumer products, (2) manufacturing capital goods, (3) new consumer products and retailing, (4) electric utilities, (5) environmental quality, (6) food production and processing, (7) government, (8) petroleum and gas, (9) construction, (10) law enforcement, and (11) highway transportation.

  2. Effect of wall to total temperature ratio variation on heat transfer to the leeside of a space shuttle configuration at M equals 10.3

    NASA Technical Reports Server (NTRS)

    Dunavant, J. C.

    1974-01-01

    An experimental study has been conducted of the influence of wall to total temperature ratio on the heat transfer to the leeside of a 040A space shuttle configuration. The heat transfer tests were made at a Mach number of 10 and a Reynolds number of one million per foot for angles of attack from 0 deg to 30 deg. Range of wall to total temperature ratio was from 0.16 to 0.43. Where the heat transfer was relatively high and the laminar boundary layer attached, the local heat transfer decreased by about 20 percent as the wall to total temperature ratio was increased from the minimum to the maximum test value. On regions of separated flow and vortex reattachment, very low heating rates were measured at some conditions and indicate significant changes are occurring in the leeside flow field. No single trend of heat transfer variation with wall to total temperature ratio could be observed.

  3. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 5: Nuclear electric propulsion vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The nuclear electric propulsion (NEP) concept design developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study is presented. The evolution of the NEP concept is described along with the requirements, guidelines, and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities and costs.

  4. Evolution of the Deep-space Galactic Cosmic Ray Lineal Energy Transfer Spectrum through Tissue Equivalent Plastic

    NASA Astrophysics Data System (ADS)

    Case, A. W.; Kasper, J. C.; Spence, H. E.; Golightly, M. J.; Schwadron, N. A.; Mazur, J. E.; Blake, J. B.; Looper, M. D.; Townsend, L.; Zeitlin, C. J.

    2011-12-01

    The Cosmic Ray Telescope for the Effects of Radiation is an energetic particle telescope that resides on the Lunar Reconnaissance Orbiter spacecraft, currently in a 50 km circular lunar polar orbit. The telescope consists of 6 silicon semi-conductor detectors placed in pairs that surround two pieces of Tissue Equivalent Plastic (TEP), which serve to absorb energy from particles as they transit through the instrument. Particles with energies greater than 12 MeV/nucleon can penetrate the outermost shield and be measured by the instrument. The primary measurement made by the instrument is of the Linear Energy Transfer (LET) of energetic particles as they transit through the telescope. CRaTER measures the LET spectrum with unprecedented energy resolution and has done so during a period of historically low solar activity that led to record high intensities of Galactic Cosmic Rays (GCR). These LET spectra are used to study changes in the properties of the incoming particles, and to make detailed measurements of the radiation doses human explorers will experience in deep space on missions to the moon, to asteroids, or to Mars. We present LET spectra accumulated during 2009 and 2010. We show how the LET spectrum evolves through the instrument as the GCR interact with the TEP. Due to the importance of these measurements for human effects, our extensive absolute calibration procedures are presented. Of particular note is a significant reduction in the flux of particles with LET greater than 10 keV/um for detectors that lie deeper within the telescope stack, due to the attenuation of high LET particles within the TEP. By measuring this attenuation we can estimate the depth in human tissue where the highest LET particles that are most likely to cause genetic damage pose the greatest threat to humans in space.

  5. Space transfer vehicle concepts and requirements study. Volume 2, book 2: System and program requirements trade studies

    NASA Astrophysics Data System (ADS)

    Weber, Gary A.; Richards, Bill; Paddock, Greg; Maricich, Peter; Bouton, Bruce; Hagen, Jim; Kolesar, Richard; Hosking, Craig; Dishman, George; Furlong, Mike

    1991-04-01

    During the 90-day study, support was provided to NASA in defining a point-of-departure space transfer vehicle (STV). The resulting STV concept was performance optimized with a two-stage LTV/LEV configuration. Appendix A reports on the effort during this period of the study. From the end of the 90-day study until the March Interim Review, effort was placed on optimizing the two-stage vehicle approach identified in the 90-day effort. After the March Interim Review, the effort was expanded to perform a full architectural trade study with the intent of developing a decision database to support STV system decisions in response to changing SEI infrastructure concepts. Several of the architecture trade studies were combined in a System Architecture Trade Study. In addition to this trade, system optimization/definition trades and analyses were completed and some special topics were addressed. Program- and system-level trade study and analyses methodologies and results are presented in this section. Trades and analyses covered in this section are: (1) a system architecture trade study; (2) evolution; (3) safety and abort considerations; (4) STV as a launch vehicle upper stage; and (5) optimum crew and cargo split.

  6. Concept for a Lunar Transfer Vehicle for Small Satellite Delivery to the Moon from the International Space Station

    NASA Technical Reports Server (NTRS)

    Elliott, John; Alkalai, Leon

    2010-01-01

    The International Space Station (ISS) has developed as a very capable center for scientific research in Lower Earth Orbit. An additional potential of the ISS that has not thus far been exploited, is the use of this orbiting plat-form for the assembly and launching of vehicles that could be sent to more distant destinations. This paper reports the results of a recent study that looked at an architecture and conceptual flight system design for a lunar transfer vehicle (LTV) that could be delivered to the ISS in segments, assembled, loaded with payload and launched from the ISS with the objective of delivering multiple small and micro satellites to lunar orbit. The design of the LTV was optimized for low cost and high payload capability, as well as ease of assembly. The resulting design would use solar electric propulsion (SEP) to carry a total payload mass of 250 kg from the ISS to a 100 km lunar orbit. A preliminary concept of operations was developed considering currently available delivery options and ISS capabili-ties that should prove flexible enough to accommodate a variety of payloads and missions. This paper will present an overview of the study, including key trades, mission and flight system design, and notional operational concept.

  7. Space Transfer Vehicle Concepts and Requirements Study. Volume 2, Book 2: System and Program Requirements Trade Studies

    NASA Technical Reports Server (NTRS)

    Weber, Gary A.; Richards, Bill; Paddock, Greg; Maricich, Peter; Bouton, Bruce; Hagen, Jim; Kolesar, Richard; Hosking, Craig; Dishman, George; Furlong, Mike

    1991-01-01

    During the 90-day study, support was provided to NASA in defining a point-of-departure space transfer vehicle (STV). The resulting STV concept was performance optimized with a two-stage LTV/LEV configuration. Appendix A reports on the effort during this period of the study. From the end of the 90-day study until the March Interim Review, effort was placed on optimizing the two-stage vehicle approach identified in the 90-day effort. After the March Interim Review, the effort was expanded to perform a full architectural trade study with the intent of developing a decision database to support STV system decisions in response to changing SEI infrastructure concepts. Several of the architecture trade studies were combined in a System Architecture Trade Study. In addition to this trade, system optimization/definition trades and analyses were completed and some special topics were addressed. Program- and system-level trade study and analyses methodologies and results are presented in this section. Trades and analyses covered in this section are: (1) a system architecture trade study; (2) evolution; (3) safety and abort considerations; (4) STV as a launch vehicle upper stage; and (5) optimum crew and cargo split.

  8. The effects of inlet turbulence and rotor/stator interactions on the aerodynamics and heat transfer of a large-scale rotating turbine model. Volume 2: Heat transfer data tabulation. 15 percent axial spacing

    NASA Technical Reports Server (NTRS)

    Dring, R. P.; Blair, M. F.; Joslyn, H. D.

    1986-01-01

    A combined experimental and analytical program was conducted to examine the effects of inlet turbulence on airfoil heat transfer. The experimental portion of the study was conducted in a large-scale (approx 5X engine), ambient temperature, rotating turbine model configured in both single stage and stage-and-a-half arrangements. Heat transfer measurements were obtained using low-conductivity airfoils with miniature thermcouples welded to a thin, electrically heated surface skin. Heat transfer data were acquired for various combinations of low or high inlet turbulence intensity, flow coefficient, first-stator/rotor axial spacing, Reynolds number and relative circumferential position of the first and second stators. Aerodynamic measurements obtained as part of the program include distributions of the mean and fluctuating velocities at the turbine inlet and, for each airfoil row, midspan airfoil surface pressures and circumferential distributions of the downstream steady state pressures and fluctuating velocities. Analytical results include airfoil heat transfer predictions produced using existing 2-D boundary layer computation schemes and an examination of solutions of the unsteady boundary layer equations. The results are reported in four separate volumes, of which this is Volume 2: Heat Transfer Data Tabulation; 15 Percent Axial Spacing.

  9. Space.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2001

    2001-01-01

    This annotated subject guide to Web sites and additional resources focuses on space and astronomy. Specifies age levels for resources that include Web sites, CD-ROMS and software, videos, books, audios, and magazines; offers professional resources; and presents a relevant class activity. (LRW)

  10. Orbital transfer vehicle - An overview

    NASA Astrophysics Data System (ADS)

    Caluori, V. A.; Saxton, D. R.

    1981-05-01

    A summary is given of the concept definition phase of NASA's Orbital Transfer Vehicle (OTV) program. The mission requirements are threefold: (1) the ability to deliver payloads well beyond the capability of any current system at low acceleration levels, (2) the extension of the cost effectiveness from reusability and operational flexibility provided by the Shuttle at LEO to the geosynchronous altitude, and (3) the provision of the round trip capability needed to service and maintain this expanded and more valuable resource at GEO. The initial Shuttle-matched, reusable OTV is shown to be cost effective with low development cost, relatively short development period and high projected reliability. The performance enhancement provided by aero-assist is discussed, which will enable the difficult round trip to be flown in a single Shuttle launch. Two methods of reducing vehicle velocity are available: (1) aeromaneuvering, which uses vehicle lift to climb or descend and thereby correct for density variations, and (2) aerobraking which varies vehicle drag directly to correct for density.

  11. Effect of a surface-to-gap temperature discontinuity on the heat transfer to reusable surface insulation tile gaps. [of the space shuttle

    NASA Technical Reports Server (NTRS)

    Throckmorton, D. A.

    1976-01-01

    An experimental investigation is presented that was performed to determine the effect of a surface-to-gap wall temperature discontinuity on the heat transfer within space shuttle, reusable surface insulation, tile gaps submerged in a thick turbulent boundary layer. Heat-transfer measurements were obtained on a flat-plate, single-gap model submerged in a turbulent tunnel wall boundary layer at a nominal free-stream Mach number of 10.3 and free-stream Reynolds numbers per meter of 1.5 million, 3.3 million and 7.8 million. Surface-to-gap wall temperature discontinuities of varying degree were created by heating the surface of the model upstream of the instrumented gap. The sweep angle of the gap was varied between 0 deg and 60 deg; gap width and depth were held constant. A surface-to-gap wall temperature discontinuity (surface temperature greater than gap wall temperature) results in increased heat transfer to the near-surface portion of the gap, as compared with the heat transfer under isothermal conditions, while decreasing the heat transfer to the deeper portions of the gap. The nondimensionalized heat transfer to the near-surface portion of the gap is shown to decrease with increasing Reynolds number; in the deeper portion of the gap, the heat transfer increases with Reynolds number.

  12. TARGET/CRYOCHIL - THERMODYNAMIC ANALYSIS AND SUBSCALE MODELING OF SPACE-BASED ORBIT TRANSFER VEHICLE CRYOGENIC PROPELLANT RESUPPLY

    NASA Technical Reports Server (NTRS)

    Defelice, D. M.

    1994-01-01

    The resupply of the cryogenic propellants is an enabling technology for space-based transfer vehicles. As part of NASA Lewis's ongoing efforts in micro-gravity fluid management, thermodynamic analysis and subscale modeling techniques have been developed to support an on-orbit test bed for cryogenic fluid management technologies. These efforts have been incorporated into two FORTRAN programs, TARGET and CRYOCHIL. The TARGET code is used to determine the maximum temperature at which the filling of a given tank can be initiated and subsequently filled to a specified pressure and fill level without venting. The main process is the transfer of the energy stored in the thermal mass of the tank walls into the inflowing liquid. This process is modeled by examining the end state of the no-vent fill process. This state is assumed to be at thermal equilibrium between the tank and the fluid which is well mixed and saturated at the tank pressure. No specific assumptions are made as to the processes or the intermediate thermodynamic states during the filling. It is only assumed that the maximum tank pressure occurs at the final state. This assumption implies that, during the initial phases of the filling, the injected liquid must pass through the bulk vapor in such a way that it absorbs a sufficient amount of its superheat so that moderate tank pressures can be maintained. It is believed that this is an achievable design goal for liquid injection systems. TARGET can be run with any fluid for which the user has a properties data base. Currently it will only run for hydrogen, oxygen, and nitrogen since pressure-enthalpy data sets have been included for these fluids only. CRYOCHIL's primary function is to predict the optimum liquid charge to be injected for each of a series of charge-hold-vent chilldown cycles. This information can then be used with specified mass flow rates and valve response times to control a liquid injection system for tank chilldown operations. This will

  13. Systemically transferred hematopoietic stem cells home to the subretinal space and express RPE-65 in a mouse model of retinal pigment epithelium damage.

    PubMed

    Atmaca-Sonmez, Pelin; Li, Yang; Yamauchi, Yasuyuki; Schanie, Carrie L; Ildstad, Suzanne T; Kaplan, Henry J; Enzmann, Volker

    2006-11-01

    Stem cell regeneration of damaged tissue has recently been reported in many different organs. Since the loss of retinal pigment epithelium (RPE) in the eye is associated with a major cause of visual loss - specifically, age-related macular degeneration - we investigated whether hematopoietic stem cells (HSC) given systemically can home to the damaged subretinal space and express markers of RPE lineage. Green fluorescent protein (GFP) cells of bone marrow origin were used in a sodium iodate (NaIO(3)) model of RPE damage in the mouse. The optimal time for adoptive transfer of bone marrow-derived stem cells relative to the time of injury and the optimal cell type [whole bone marrow, mobilized peripheral blood, HSC, facilitating cells (FC)] were determined by counting the number of GFP(+) cells in whole eye flat mounts. Immunocytochemistry was performed to identify the bone marrow origin of the cells in the RPE using antibodies for CD45, Sca-1, and c-kit, as well as the expression of the RPE-specific marker, RPE-65. The time at which bone marrow-derived cells were adoptively transferred relative to the time of NaIO(3) injection did not significantly influence the number of cells that homed to the subretinal space. At both one and two weeks after intravenous (i.v.) injection, GFP(+) cells of bone marrow origin were observed in the damaged subretinal space, at sites of RPE loss, but not in the normal subretinal space. The combined transplantation of HSC+FC cells appeared to favor the survival of the homed stem cells at two weeks, and RPE-65 was expressed by adoptively transferred HSC by four weeks. We have shown that systemically injected HSC homed to the subretinal space in the presence of RPE damage and that FC promoted survival of these cells. Furthermore, the RPE-specific marker RPE-65 was expressed on adoptively transferred HSC in the denuded areas. PMID:16949576

  14. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document. Volume 1: Major trades. Book 1: Draft final

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This document presents trade studies and reference concept designs accomplished during a study of Space Transfer Concepts and Analyses for Exploration Missions (STCAEM). This volume contains the major top level trades, level 2 trades conducted in support of NASA's Lunar/Mars Exploration Program Office, and a synopsis of the vehicles for different propulsion systems under trade consideration. The vehicles are presented in more detail in other volumes of this report. Book 1 of Volume 1 covers the following analyses: lunar/Mars commonality trades, lunar/Mars mission operations, and Mars transfer systems.

  15. Space-based retrievals of air-sea gas transfer velocities using altimeters: Calibration for dimethyl sulfide

    NASA Astrophysics Data System (ADS)

    Goddijn-Murphy, Lonneke; Woolf, David K.; Marandino, Christa

    2012-08-01

    This study is the first to directly correlate gas transfer velocity, measured at sea using the eddy-correlation (EC) technique, and satellite altimeter backscattering. During eight research cruises in different parts of the world, gas transfer velocity of dimethyl sulfide (DMS) was measured. The sample times and locations were compared with overpass times and locations of remote sensing satellites carrying Ku-band altimeters: ERS-1, ERS-2, TOPEX, POSEIDON, GEOSAT Follow-On, JASON-1, JASON-2 and ENVISAT. The result was 179 pairs of gas transfer velocity measurements and backscattering coefficients. An inter-calibration of the different altimeters significantly reduced data scatter. The inter-calibrated data was best fitted to a quadratic relation between the inverse of the backscattering coefficients and the gas transfer velocity measurements. A gas transfer parameterization based on backscattering, corresponding with sea surface roughness, might be expected to perform better than wind speed-based parameterizations. Our results, however, did not show improvement compared to direct correlation of shipboard wind speeds. The relationship of gas transfer velocity to satellite-derived backscatter, or wind speed, is useful to provide retrieval algorithms. Gas transfer velocity (cm/hr), corrected to a Schmidt number of 660, is proportional to wind speed (m/s). The measured gas transfer velocity is controlled by both the individual water-side and air-side gas transfer velocities. We calculated the latter using a numerical scheme, to derive water-side gas transfer velocity. DMS is sufficiently soluble to neglect bubble-mediated gas transfer, thus, the DMS transfer velocities could be applied to estimate water-side gas transfer velocities through the unbroken surface of any other gas.

  16. Statistical analysis of the polar electrojet influence on geomagnetic transfer functions estimates over wide time and space scales.

    NASA Astrophysics Data System (ADS)

    Rizzello, Daniele; Armadillo, Egidio; Manzella, Adele

    2013-04-01

    Statistical analysis of the polar electrojet influence on geomagnetic transfer functions estimates over wide time and space scales. D.Rizzello(1),E.Armadillo(1),A.Manzella(2) 1)DISTAV - University of Genoa,Italy. 2)Institute of Geosciences and Earth Resources - CNR, Pisa, Italy. Magnetotelluric (MT) and magnetovariational (MV) investigations can provide original information and constraints on the electrical conductivity, thermal state and structure of the crust and mantle at the base of the polar ice sheets. These methods provide depth resolution, lacking in potential field methods, and can reach high investigation depth, an invaluable advantage where very difficult logistic conditions prevent or limit the use of active methods such as seismic surveys. However, MT/MV surveys have not been applied extensively in polar areas mainly because electromagnetic data could be biased by the polar electrojet current systems (PEJ) occurring at high geomagnetic latitude. In fact, close to the auroral oval, the electromagnetic fields at ground may violate the uniform plane wave assumption at the base of standard MT/MV data processing, resulting in possible erroneous interpretations of the Earth's deep conductivity structure. It has been shown that a careful selection of events to be analyzed may decrease bias, and different robust techniques have been developed and applied. Even if the source currents flow in complex 3D systems that change from event to event in an unpredictable way, some general rules have been observed. Violations of uniform plane wave source assumption are enhanced during higher geomagnetic activity induced by high solar activity, because PEJ equivalent geometry becomes more complicated, affecting also EM field at lower latitudes. Differences in the degree of source distortions have also been reported between day/night and seasonal observations. The ISEE (Ice Sheet Electromagnetic Experiment) project, founded by the Italian National Antarctic Research

  17. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 3: Nuclear thermal rocket vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This document presents the nuclear thermal rocket (NTR) concept design developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study. The evolution of the NTR concept is described along with the requirements, guidelines and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities and costs.

  18. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 4: Solar electric propulsion vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This document presents the solar electric propulsion (SEP) concept design developed as part of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study. The evolution of the SEP concept is described along with the requirements, guidelines and assumptions for the design. Operating modes and options are defined and a systems description of the vehicle is presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities, and costs.

  19. Space transfer concepts and analysis for exploration missions. Implementation plan and element description document (draft final). Volume 2: Cryo/aerobrake vehicle

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The cryogenic/aerobrake (CAB) and the cryogenic all-propulsive (CAP) concept designs developed in support of the Space Transfer Concepts and Analysis for Exploration Missions (STCAEM) study are presented. The evolution of the CAB and CAP concepts is described along with the requirements, guidelines and assumptions for the designs. Operating modes and options are defined and systems descriptions of the vehicles are presented. Artificial gravity configuration options and space and ground support systems are discussed. Finally, an implementation plan is presented which addresses technology needs, schedules, facilities, and costs.

  20. Heat transfer tests of the NASA-MSC space shuttle configuration at the Langley Research Center Mach 8 Variable Density Facility

    NASA Technical Reports Server (NTRS)

    Connor, L. E.; Sparks, V. W.; Bhadsavle, A. G.

    1971-01-01

    The experimental investigations performed on the NASA-Manned Spacecraft Center Space Shuttle orbiter and booster configurations at a Mach 8 variable density facility are presented. The test program was a series of aerothermodynamic wind tunnel tests that were run over a range of angles of attack, yaw angles, and Reynolds numbers. Objectives of the test program were to obtain heat transfer data over the NASA-Manned Spacecraft Center Space Shuttle orbiter, booster, and launch configurations for a range of angles of attack from - 20 to + 30 deg, yaw angles of 0 and + or - 6 deg, and Reynolds numbers of 0.6, 2.0, and 3.7 x one million. The phase-change coating technique was used to obtain heat transfer data. Information received from these tests will be instrumental in performing thermal protection systems studies and vehicle aerodynamic design.

  1. Effect of element size on the solution accuracies of finite-element heat transfer and thermal stress analyses of space shuttle orbiter

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Olona, Timothy

    1987-01-01

    The effect of element size on the solution accuracies of finite-element heat transfer and thermal stress analyses of space shuttle orbiter was investigated. Several structural performance and resizing (SPAR) thermal models and NASA structural analysis (NASTRAN) structural models were set up for the orbiter wing midspan bay 3. The thermal model was found to be the one that determines the limit of finite-element fineness because of the limitation of computational core space required for the radiation view factor calculations. The thermal stresses were found to be extremely sensitive to a slight variation of structural temperature distributions. The minimum degree of element fineness required for the thermal model to yield reasonably accurate solutions was established. The radiation view factor computation time was found to be insignificant compared with the total computer time required for the SPAR transient heat transfer analysis.

  2. Experimental and analytical derivation of arc-heater scaling laws for simulating high-enthalpy environments for Aeroassisted Orbital Transfer Vehicle application

    NASA Technical Reports Server (NTRS)

    Winovich, W.; Balboni, J.; Balakrishnan, A.

    1985-01-01

    The computer code ARCFLO II was used as a guide to increase the performance of the Interaction Heating Facility at Ames Research Center. A closed-form scaling law relation was derived that provides an understanding of the factors that affect enthalpy in the constricted-arc heater. From a study of this scaling law, it is concluded that at constant pressure, enthalpy is proportional to current density raised to the 0.60 power for current densities from 80 to 150 A/sq cm. At constant current density, enthalpy is inversely proportional to pressure to the nth power, where n varies from 0.14 to 0.43, depending on the current density. Radiative heat losses are responsible for the falloff in performance at combinations of high current density and high pressure. An analytical, closed form scaling law based on a constant-temperature arc-core model agrees qualitatively with the scaling law deduced from ARCFLO II.

  3. Natural convection mass transfer at a vertical array of closely-spaced horizontal cylinders with special reference to electrochemical reactor design

    SciTech Connect

    Sedahmed, G.H.; Nirdosh, I.

    1995-06-01

    Many industrial electrochemical processes such as electrowinning of metals, electrochemical pollution control, and electroorganic and electroinorganic syntheses are diffusion-controlled processes whose rates depend on the geometry of the working electrode as well as the prevailing hydrodynamic conditions. Recently much work has been done to develop new electrochemical reactors which are more efficient than the traditional parallel plate electrochemical reactor used in conducting such processes. In line with this, the object of the present work was to study the natural convection mass transfer behavior of a new electrode geometry, namely an array of closely-spaced horizontal tubes. Natural convection mass transfer at a vertical array of closely-spaced horizontal cylinders was studied by an electrochemical technique involving the measurement of the limiting current of the cathodic deposition of copper from acidified copper sulfate solution. Various combinations of solution concentration, cylinder diameter, and number of cylinders per array were used including experiments on single cylinders. The mass transfer coefficient at the array was found to decrease with increasing number of cylinders, pass through a minimum, and then increase with further increase in the number of cylinders per array; the mass transfer coefficient increased with increasing cylinder diameter in the array. Mass transfer data for different arrays were correlated for the range 6.3 {times} 10{sup 9} < ScGr < 3.63 {times} 10{sup 10} by the equation Sh = 0.455(ScGr){sup 0.25} and for the range 6.3 {times} 10{sup 10} < ScGr < 3.63 {times} 10{sup 12} by the equation Sh = 0.0064(ScGr){sup 0.42}. The characteristic length used in the above correlations was obtained by dividing the array area by the perimeter projected onto a horizontal plane. Practical implications of the present results in designing electrochemical reactors with heat transfer facilities are highlighted.

  4. Heat and moisture transfer in gaps between sweating imitation skin and nonwoven cloth: effect of gap space and alignment of skin and clothing on the moisture transfer

    NASA Astrophysics Data System (ADS)

    Morozumi, Yoshio; Akaki, Kenichi; Tanabe, Naomasa

    2012-07-01

    This study investigates heat and moisture transfer between a sweating film and a nonwoven sheet both experimentally and numerically. A mathematical model based on heat conduction and moisture diffusion in both the air gap and cloth is presented. The evaporation rate and surface temperature of the sweating film are well predicted under various conditions such as air gap height, heating conditions, and sweating film orientation by evaluating the effective thermal conductivity and diffusion coefficient from the empirical equations of the Nusselt number for a fluid layer, even though the air gap height is sufficiently large to cause natural convections.

  5. Heat transfer in space systems; Proceedings of the Symposium, AIAA/ASME Thermophysics and Heat Transfer Conference, Seattle, WA, June 18-20, 1990

    NASA Astrophysics Data System (ADS)

    Chan, S. H.; Anderson, E. E.; Simoneau, R. J.; Chan, C. K.; Pepper, D. W.

    Theoretical and experimental studies of heat-tranfer in a space environment are discussed in reviews and reports. Topics addressed include a small-scale two-phase thermosiphon to cool high-power electronics, a low-pressure-drop heat exchanger with integral heat pipe, an analysis of the thermal performance of heat-pipe radiators, measurements of temperature and concentration fields in a rectangular heat pipe, and a simplified aerothermal heating method for axisymmetric blunt bodies. Consideration is given to entropy production in a shock wave, bubble-slug transition in a two-phase liquid-gas flow under microgravity, plasma arc welding under normal and zero gravity, the Microgravity Thaw Experiment, the flow of a thin film on stationary and rotating disks, an advanced ceramic fabric body-mounted radiator for Space Station Freedom phase 0 design, and lunar radiators with specular reflectors.

  6. Heat transfer in space systems; Proceedings of the Symposium, AIAA/ASME Thermophysics and Heat Transfer Conference, Seattle, WA, June 18-20, 1990

    NASA Technical Reports Server (NTRS)

    Chan, S. H. (Editor); Anderson, E. E. (Editor); Simoneau, R. J. (Editor); Chan, C. K. (Editor); Pepper, D. W. (Editor)

    1990-01-01

    Theoretical and experimental studies of heat-tranfer in a space environment are discussed in reviews and reports. Topics addressed include a small-scale two-phase thermosiphon to cool high-power electronics, a low-pressure-drop heat exchanger with integral heat pipe, an analysis of the thermal performance of heat-pipe radiators, measurements of temperature and concentration fields in a rectangular heat pipe, and a simplified aerothermal heating method for axisymmetric blunt bodies. Consideration is given to entropy production in a shock wave, bubble-slug transition in a two-phase liquid-gas flow under microgravity, plasma arc welding under normal and zero gravity, the Microgravity Thaw Experiment, the flow of a thin film on stationary and rotating disks, an advanced ceramic fabric body-mounted radiator for Space Station Freedom phase 0 design, and lunar radiators with specular reflectors.

  7. DNA Strand Breaks, Photoproducts, and Repair in Analog Space and Mars Environments: Implications for Microbial Interplanetary Transfer

    NASA Astrophysics Data System (ADS)

    Nicholson, W. L.; Möller, R.; Douki, T.; Robles, J.; Bruno, G.; Fajardo-Cavazos, P.; Schuerger, A. C.

    2008-03-01

    Bacterial spores are considered good candidates for interplanetary transport by natural impacts or human spaceflight. In this work we consider the mechanisms of DNA damage and repair in spores subjected to a hypothetical Earth-to-Mars transfer.

  8. Free transfer of a large sensory flap from the first web space and dorsum of the foot including the second toe for reconstruction of a mutilated hand.

    PubMed

    Rose, E H; Buncke, H J

    1981-03-01

    A 19-year-old man sustained a mutilating crush injury in August, 1978, in an 80-ton punch press. The injury resulted in transmetacarpal amputations of the index through little fingers. The thumb was revascularized by microvascular anastomoses. The replanted index to the little finger position failed. A free transfer of the patient's second toe to the fifth metacarpal was done to provide a post to oppose the thumb. The first web space of the toe was used in expanding the contracted single cleft of the hand. The innervated dorsal foot flap provided coverage for the dorsal surface of the hand. Anatomically, the entire composite transfer was supported by the dorsalis pedis artery anastomosed to the radial artery. The nerve sutures were between the plantar digital nerves and sensory fascicles of the median nerve and the deep peroneal to the dorsal branch of the radial. The extensor and flexor tendons were also repaired. This procedure differs from the neurovascular island transfer of the first web described by Strauch and Tsur by inclusion of the second toe in the free transfer. PMID:7229297

  9. Development of Flow and Heat Transfer Models for the Carbon Fiber Rope in Nozzle Joints of the Space Shuttle Reusable Solid Rocket Motor

    NASA Technical Reports Server (NTRS)

    Wang, Q.; Ewing, M. E.; Mathias, E. C.; Heman, J.; Smith, C.; McCool, Alex (Technical Monitor)

    2001-01-01

    Methodologies have been developed for modeling both gas dynamics and heat transfer inside the carbon fiber rope (CFR) for applications in the space shuttle reusable solid rocket motor joints. Specifically, the CFR is modeled using an equivalent rectangular duct with a cross-section area, friction factor and heat transfer coefficient such that this duct has the same amount of mass flow rate, pressure drop, and heat transfer rate as the CFR. An equation for the friction factor is derived based on the Darcy-Forschheimer law and the heat transfer coefficient is obtained from pipe flow correlations. The pressure, temperature and velocity of the gas inside the CFR are calculated using the one-dimensional Navier-Stokes equations. Various subscale tests, both cold flow and hot flow, have been carried out to validate and refine this CFR model. In particular, the following three types of testing were used: (1) cold flow in a RSRM nozzle-to-case joint geometry, (2) cold flow in a RSRM nozzle joint No. 2 geometry, and (3) hot flow in a RSRM nozzle joint environment simulator. The predicted pressure and temperature history are compared with experimental measurements. The effects of various input parameters for the model are discussed in detail.

  10. Future space transportation systems analysis study. Phase 1: Technical report, appendices. [a discussion of orbit transfer vehicles, lunar transport vehicles, space shuttles, and reusable spacecraft

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The transportation mass requirements developed for each mission and transportation mode were based on vehicle systems sized to fit the exact needs of each mission (i.e. rubber vehicles). The parametric data used to derive the mass requirements for each mission and transportation mode are presented to enable accommodation of possible changes in mode options or payload definitions. The vehicle sizing and functional requirements used to derive the parametric data will form the basis for conceptual configurations of the transportation elements in a later phase of study. An investigation of the weight growth approach to future space transportation systems analysis is presented. Parameters which affect weight growth, past weight histories, and the current state of future space-mission design are discussed. Weight growth factors of from 10 percent to 41 percent were derived for various missions or vehicles.

  11. Hot-electron real-space transfer and longitudinal transport in dual AlGaN/AlN/{AlGaN/GaN} channels

    NASA Astrophysics Data System (ADS)

    Šermukšnis, E.; Liberis, J.; Matulionis, A.; Avrutin, V.; Ferreyra, R.; Özgür, Ü.; Morkoç, H.

    2015-03-01

    Real-space transfer of hot electrons is studied in dual-channel GaN-based heterostructure operated at or near plasmon-optical phonon resonance in order to attain a high electron drift velocity at high current densities. For this study, pulsed electric field is applied in the channel plane of a nominally undoped Al0.3Ga0.7N/AlN/{Al0.15Ga0.85N/GaN} structure with a composite channel of Al0.15Ga0.85N/GaN, where the electrons with a sheet density of 1.4 × 1013 cm-2, estimated from the Hall effect measurements, are confined. The equilibrium electrons are situated predominantly in the Al0.15Ga0.85N layer as confirmed by capacitance-voltage experiment and Schrödinger-Poisson modelling. The main peak of the electron density per unit volume decreases as more electrons occupy the GaN layer at high electric fields. The associated decrease in the plasma frequency induces the plasmon-assisted decay of non-equilibrium optical phonons (hot phonons) confirmed by the decrease in the measured hot-phonon lifetime from 0.95 ps at low electric fields down below 200 fs at fields of E \\gt 4 kV cm-1 as the plasmon-optical phonon resonance is approached. The onset of real-space transfer is resolved from microwave noise measurements: this source of noise dominates for E \\gt 8 kV cm-1. In this range of fields, the longitudinal current exceeds the values measured for a mono channel reference Al0.3Ga0.7N/AlN/GaN structure. The results are explained in terms of the ultrafast decay of hot phonons and reduced alloy scattering caused by the real-space transfer in the composite channel.

  12. Simulation of a turbulent supersonic underexpanded jet flowing into a submerged space with the help of a shear stress transfer model

    NASA Astrophysics Data System (ADS)

    Isaev, S. A.; Lipnitskii, Yu. M.; Baranov, P. A.; Panasenko, A. V.; Usachov, A. E.

    2012-11-01

    We have calculated the flow of an axisymmetric turbulent supersonic underexpanded jet into a submerged space with the help of the VP2/3 package as part of the generalized pressure correction procedure. The shear stress transfer model modified with account for the curvature of streamlines has been verified on the basis of comparison with V. I. Zapryagaev's data obtained at the S. A. Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch of the Russian Academy of Sciences. The influence of the generated vortex viscosity on the shock-wave structure of the jet, the field of flow parameters, and the turbulence characteristics has been analyzed.

  13. Transfer impedance measurements of the space shuttle Solid Rocket Motor (SRM) joints, wire meshes and a carbon graphite motor case

    NASA Technical Reports Server (NTRS)

    Papazian, Peter B.; Perala, Rodney A.; Curry, John D.; Lankford, Alan B.; Keller, J. David

    1988-01-01

    Using three different current injection methods and a simple voltage probe, transfer impedances for Solid Rocket Motor (SRM) joints, wire meshes, aluminum foil, Thorstrand and a graphite composite motor case were measured. In all cases, the surface current distribution for the particular current injection device was calculated analytically or by finite difference methods. The results of these calculations were used to generate a geometric factor which was the ratio of total injected current to surface current density. The results were validated in several ways. For wire mesh measurements, results showed good agreement with calculated results for a 14 by 18 Al screen. SRM joint impedances were independently verified. The filiment wound case measurement results were validated only to the extent that their curve shape agrees with the expected form of transfer impedance for a homogeneous slab excited by a plane wave source.

  14. Optimum configuration of high-lift aeromaneuvering orbital transfer vehicles in viscous flow

    NASA Technical Reports Server (NTRS)

    Davies, C. B.; Park, C.

    1985-01-01

    The results of an analysis to determine the geometrical configuration of an aeroassisted transfer vehicle with a high lift-to-drag ratio (L/D) are described and the constraints imposed on this type of entry vehicle are considered. The aerodynamic characteristics of three configurations, a flat-plate delta wing, a truncated straight cone, and a truncated bent biconic are compared. The effect of viscosity is included in the analysis which examines the rounding of the sharp leading edges. It is shown that, under the constraints of carrying a given volume in the dead air region, the values of L/D are similar for each configuration and that a small blunt leading edge only slightly affects each vehicle's aerodynamic performance, causing less than a 5 percent drop in L/D. The truncated bent biconic is found to be the only configuration that provides the necessary stabilizing moments.

  15. Long-Range Reduced Predictive Information Transfers of Autistic Youths in EEG Sensor-Space During Face Processing.

    PubMed

    Khadem, Ali; Hossein-Zadeh, Gholam-Ali; Khorrami, Anahita

    2016-03-01

    The majority of previous functional/effective connectivity studies conducted on the autistic patients converged to the underconnectivity theory of ASD: "long-range underconnectivity and sometimes short-rang overconnectivity". However, to the best of our knowledge the total (linear and nonlinear) predictive information transfers (PITs) of autistic patients have not been investigated yet. Also, EEG data have rarely been used for exploring the information processing deficits in autistic subjects. This study is aimed at comparing the total (linear and nonlinear) PITs of autistic and typically developing healthy youths during human face processing by using EEG data. The ERPs of 12 autistic youths and 19 age-matched healthy control (HC) subjects were recorded while they were watching upright and inverted human face images. The PITs among EEG channels were quantified using two measures separately: transfer entropy with self-prediction optimality (TESPO), and modified transfer entropy with self-prediction optimality (MTESPO). Afterwards, the directed differential connectivity graphs (dDCGs) were constructed to characterize the significant changes in the estimated PITs of autistic subjects compared with HC ones. By using both TESPO and MTESPO, long-range reduction of PITs of ASD group during face processing was revealed (particularly from frontal channels to right temporal channels). Also, it seemed the orientation of face images (upright or upside down) did not modulate the binary pattern of PIT-based dDCGs, significantly. Moreover, compared with TESPO, the results of MTESPO were more compatible with the underconnectivity theory of ASD in the sense that MTESPO showed no long-range increase in PIT. It is also noteworthy that to the best of our knowledge it is the first time that a version of MTE is applied for patients (here ASD) and it is also its first use for EEG data analysis. PMID:26433373

  16. Subject-to-subject transfer for CSP based BCIs: feature space transformation and decision-level fusion.

    PubMed

    Heger, Dominic; Putze, Felix; Herff, Christian; Schultz, Tanja

    2013-01-01

    Modern Brain Computer Interfaces (BCIs) usually require a calibration session to train a machine learning system before each usage. In general, such trained systems are highly specialized to the subject's characteristic activation patterns and cannot be used for other sessions or subjects. This paper presents a feature space transformation that transforms features generated using subject-specific spatial filters into a subject-independent feature space. The transformation can be estimated from little adaptation data of the subject. Furthermore, we combine three different Common Spatial Pattern based feature extraction approaches using decision-level fusion, which enables BCI use when little calibration data is available, but also outperformed the subject-dependent reference approaches for larger amounts of training data. PMID:24111010

  17. Half space albedo problem for the nonconservative vector equation of transfer with a combination of Rayleigh and isotropic scattering

    NASA Astrophysics Data System (ADS)

    Şenyiğit, M.

    2016-09-01

    The half-space albedo problem has been solved for a combination of Rayleigh and isotropic scattering using HN method which is developed for the neutron transport studies. The numerical results are compared with exact values obtained using variational method and Chandrasekhar's equation for the {H}-matrix. The analytical solutions of HN method are easy to handle in comparison with the other methods. The numerical results are in good agreement with previous works in literature.

  18. Development of precise tuning method of inter-dot spacing and resonant energy transfer between Au clusters

    NASA Astrophysics Data System (ADS)

    Inada, Mitsuru; Yoshihara, Yoshihiro; Kawasaki, Hideya; Iwasaki, Yasuhiko; Saitoh, Tadashi; Umezu, Ikurou; Sugimura, Akira

    2011-09-01

    A device to control strength of interactions between adjacent nanostructures, namely Precise Interaction Control System for Nanostructures (PICSN) is developed. The PICSN is operated by combinations of DC motor and capacitancepositioning sensor. In this system, nanostructures are deposited on a flexible substrate and the strength of interactions can be controlled by changing a distance between adjacent nanostructures, stretching or shrinking the flexible substrate. Using the PICSN, we investigate photoluminescence of Au nanoclusters (NCs), which include at least Au5, Au8 and Au13 NCs, deposited on poly(dimethylsiloxane) substrate. We observed a blue shift of PL peak position with increasing interdot distance. Considering the relationship between absorption and emission energies of Au NCs, the blue shift is thought to be a result of fluorescent resonant energy transfer from smaller sized Au NCs to larger ones.

  19. The Successful Transfer of Space Derived Convergent Spray: An Application for Industrial Roof Coatings and Interstate Bridge Repair

    NASA Technical Reports Server (NTRS)

    McMillan, Vernotto C.

    1998-01-01

    A partnership was formed between the National Aeronautics and Space Administration (NASA), the Environmental Protection Agency (EPA), and United Technologies USBI Company to develop, demonstrate, and evaluate a technology that uses a solventless spray process for depositing a lightweight, highly filled roof coating on low-sloped commercial roofs. Although the levels of volatile organic compound (VOC) emissions from industrial roof coating's and paint operations have been reduced in recent years, this partnership,was an effort to further reduce VOC emission levels and to also demonstrate the use of reclaimed automobile tire rubber as a filler material in roof coating systems. Different materials and coatings were evaluated and tested before the final selection used to coat the roofs of two small buildings at NASA's Marshall Space Flight Center during fiscal year 1997. The project successfully leveraged the investment of EPA, NASA and private sector resources to demonstrate a pre-commercial roofing coating process. This process utilizes the Convergent Spray Technologies process, which was initially developed by USBI to apply highly-filled, thermal protection coatings to the Space Shuttle Solid Rocket Boosters. A second partnership between the NASA, Federal Highway Administration, Alabama Department of Transportation and USBI Company was formed to develop and demonstrate the Convergent Spray Technology as a method of applying a skid resistant coating to interstate roads and concrete bridge decking's. Again, different materials and coatings were evaluated and tested before the final selection of ground flint and resin. Two field demonstrations were performed during fiscal year 1997 for the purpose of evaluating the coating system under actual highway conditions. These coatings were applied on Interstate 65 near Huntsville Alabama, and in the Mobile Bankhead tunnel. The system performed this task without the use of harmful solvents, and accomplished the process in a

  20. Concept of contrast transfer function for edge illumination x-ray phase-contrast imaging and its comparison with the free-space propagation technique.

    PubMed

    Diemoz, Paul C; Vittoria, Fabio A; Olivo, Alessandro

    2016-05-16

    Previous studies on edge illumination (EI) X-ray phase-contrast imaging (XPCi) have investigated the nature and amplitude of the signal provided by this technique. However, the response of the imaging system to different object spatial frequencies was never explicitly considered and studied. This is required in order to predict the performance of a given EI setup for different classes of objects. To this scope, in the present work we derive analytical expressions for the contrast transfer function of an EI imaging system, using the approximation of near-field regime, and study its dependence upon the main experimental parameters. We then exploit these results to compare the frequency response of an EI system with respect of that of a free-space propagation XPCi one. The results achieved in this work can be useful for predicting the signals obtainable for different types of objects and also as a basis for new retrieval methods. PMID:27409946

  1. Heat-transfer tests on the Rockwell International space shuttle orbiter with and without simulated protuberances. [wind tunnel tests of scale models at hypersonic flow

    NASA Technical Reports Server (NTRS)

    Carter, L. D.; Kaul, C. E.

    1975-01-01

    Aerothermodynamic tests on the forward half of the Rockwell International Space Shuttle Orbiter Configuration 140C were conducted at Mach number 8. The phase-change paint and thin-skin thermocouple techniques were used to determine the aerodynamic heating rates on the Orbiter models during simulated atmospheric reentry. Smooth 0.04-scale models and models with scaled protuberances and indentations which simulated the windshields, cargo bay door hinges, vents, and thruster nozzles were tested over an angle-of-attack range from 20 to 45 deg at yaw angles from -5 to 5 deg and at Reynolds numbers, based on the total Orbiter scaled length, from 2.15 to 15.9 million. Comparisons of the model heat-transfer rates obtained with a smooth surface and with scaled protuberances are presented.

  2. Electron transfer through a molecular wire: Consideration of electron-vibrational coupling within the Liouville space pathway technique

    NASA Astrophysics Data System (ADS)

    May, V.

    2002-12-01

    To fully account for electron-vibrational coupling and vibrational relaxation in the course of electron motion through a molecular wire a density operator approach is utilized. If combined with a particular projection operator technique a generalized master equation can be derived which governs the populations of the electronic wire states. The respective memory kernels are determined beyond any perturbation theory with respect to the electron-vibrational coupling and can be classified via so-called Liouville space pathways. An ordering of the different contributions to the current-voltage characteristics becomes possible by introducing an electron transmission coefficient which describes ballistic as well as inelastic electron transport through the wire. The general derivations are illustrated by numerical calculations which demonstrate the drastic influence of the electron-vibrational coupling on the wire transmission coefficient as well as on the current-voltage characteristics.

  3. Assessment of the ultraviolet radiation field in ocean waters from space-based measurements and full radiative-transfer calculations.

    PubMed

    Vasilkov, Alexander P; Herman, Jay R; Ahmad, Ziauddin; Kahru, Mati; Mitchell, B Greg

    2005-05-10

    Quantitative assessment of the UV effects on aquatic ecosystems requires an estimate of the in-water radiation field. Actual ocean UV reflectances are needed for improving the total ozone retrievals from the total ozone mapping spectrometer (TOMS) and the ozone monitoring instrument (OMI) flown on NASA's Aura satellite. The estimate of underwater UV radiation can be done on the basis of measurements from the TOMS/OMI and full models of radiative transfer (RT) in the atmosphere-ocean system. The Hydrolight code, modified for extension to the UV, is used for the generation of look-up tables for in-water irradiances. A look-up table for surface radiances generated with a full RT code is input for the Hydrolight simulations. A model of seawater inherent optical properties (IOPs) is an extension of the Case 1 water model to the UV. A new element of the IOP model is parameterization of particulate matter absorption based on recent in situ data. A chlorophyll product from ocean color sensors is input for the IOP model. Verification of the in-water computational scheme shows that the calculated diffuse attenuation coefficient Kd is in good agreement with the measured Kd. PMID:15943340

  4. A study of boiling heat transfer as applied to the cooling of ball bearings in the high pressure oxygen turbopump of the space shuttle main engine

    NASA Technical Reports Server (NTRS)

    Schreiber, Will

    1986-01-01

    Two sets of ball bearings support the main shaft within the High Pressure Oxygen Turbopump (HPOTP) in the Space Shuttle Main Engine (SSME). In operation, these bearings are cooled and lubricated with high pressure liquid oxygen (LOX) flowing axially through the bearing assembly. Currently, modifications in the assembly design are being contemplated in order to enhance the lifetime of the bearings and to allow the HPOTP to operate under larger loads. An understanding of the fluid dynamics and heat transfer characteristics of the flowing LOX is necessary for the implementation of these design changes. The proposed computational model of the LOX fluid dynamics, in addition to dealing with a turbulent flow in a complex geometry, must address the complication associated with boiling and two-phase flow. The feasibility of and possible methods for modeling boiling heat transfer are considered. The theory of boiling as pertains to this particular problem is reviewed. Recommendations are given for experiments which would be necessary to establish validity for correlations needed to model boiling.

  5. Exploring the Parameter Space of the Coarse-Grained UNRES Force Field by Random Search: Selecting a Transferable Medium-Resolution Force Field

    PubMed Central

    HE, YI; XIAO, YI; LIWO, ADAM; SCHERAGA, HAROLD A.

    2009-01-01

    We explored the energy-parameter space of our coarse-grained UNRES force field for large-scale ab initio simulations of protein folding, to obtain good initial approximations for hierarchical optimization of the force field with new virtual-bond-angle bending and side-chain-rotamer potentials which we recently introduced to replace the statistical potentials. 100 sets of energy-term weights were generated randomly, and good sets were selected by carrying out replica-exchange molecular dynamics simulations of two peptides with a minimal α-helical and a minimal β-hairpin fold, respectively: the tryptophan cage (PDB code: 1L2Y) and tryptophan zipper (PDB code: 1LE1). Eight sets of parameters produced native-like structures of these two peptides. These eight sets were tested on two larger proteins: the engrailed homeodomain (PDB code: 1ENH) and FBP WW domain (PDB code: 1E0L); two sets were found to produce native-like conformations of these proteins. These two sets were tested further on a larger set of nine proteins with α or α + β structure and found to locate native-like structures of most of them. These results demonstrate that, in addition to finding reasonable initial starting points for optimization, an extensive search of parameter space is a powerful method to produce a transferable force field. PMID:19242966

  6. Characterization of dynamic thermal control schemes and heat transfer pathways for incorporating variable emissivity electrochromic materials into a space suit heat rejection system

    NASA Astrophysics Data System (ADS)

    Massina, Christopher James

    The feasibility of conducting long duration human spaceflight missions is largely dependent on the provision of consumables such as oxygen, water, and food. In addition to meeting crew metabolic needs, water sublimation has long served as the primary heat rejection mechanism in space suits during extravehicular activity (EVA). During a single eight hour EVA, approximately 3.6 kg (8 lbm) of water is lost from the current suit. Reducing the amount of expended water during EVA is a long standing goal of space suit life support systems designers; but to date, no alternate thermal control mechanism has demonstrated the ability to completely eliminate the loss. One proposed concept is to convert the majority of a space suit's surface area into a radiator such that the local environment can be used as a radiative thermal sink for rejecting heat without mass loss. Due to natural variations in both internal (metabolic) loads and external (environmental) sink temperatures, radiative transport must be actively modulated in order to maintain an acceptable thermal balance. Here, variable emissivity electrochromic devices are examined as the primary mechanism for enabling variable heat rejection. This dissertation focuses on theoretical and empirical evaluations performed to determine the feasibility of using a full suit, variable emissivity radiator architecture for space suit thermal control. Operational envelopes are described that show where a given environment and/or metabolic load combination may or may not be supported by the evaluated thermal architecture. Key integration considerations and guidelines include determining allowable thermal environments, defining skin-to-radiator heat transfer properties, and evaluating required electrochromic performance properties. Analysis also considered the impacts of dynamic environmental changes and the architecture's extensibility to EVA on the Martian surface. At the conclusion of this work, the full suit, variable emissivity

  7. Hydrogen maser clocks in space for solid-Earth research and time-transfer applications: Experiment overview and evaluation of Russian miniature sapphire loaded cavity

    NASA Technical Reports Server (NTRS)

    Busca, G.; Bernier, L. G.; Silvestrin, P.; Feltham, S.; Gaygerov, B. A.; Tatarenkov, V. M.

    1994-01-01

    The Observatoire Cantonal de Neuchatel (ON) is developing for ESTEC a compact H-maser for space use based upon a miniature sapphire loaded microwave cavity, a technique pioneered at VNIIFTRI. Various contacts between West-European parties, headed by ESA, and the Russian parties, headed by ESA, led to the proposal for flying two H-masers on Meteor 3M, a Russian meteorology satellite in low polar orbit. The experiment will include two masers, one provided by ON and the other by VNIIFTRI. T/F transfer and precise positioning will be performed by both a microwave link, using PRARE equipment, and an optical link, using LASSO-like equipment. The main objectives of the experiment are precise orbit determination and point positioning for geodetic/geophysical research, ultra-accurate time comparison and dissemination as well as in-orbit demonstration of operation and performance of H-masers. Within the scope of a preliminary space H-maser development phase performed for ESTEC at ON in preparation to the joint experiment, a Russian miniature sapphire loaded microwave cavity, on loan from VNIIFTRI, was evaluated in a full-size EFOS hydrogen maser built by ON. The experimental evaluation confirmed the theoretical expectation that with a hydrogen storage volume of only 0.65 liter an atomic quality factor of 1.5 x 10(exp 9) can be obtained for a -105 dBm output power. This represents a theoretical Allan deviation of 1.7 x 10(exp -15) averaged on a 1000 s time interval. From a full-size design to a compact one, therefore, the sacrifice in performance due to the reduction of the storage volume is very small.

  8. Transfer of Learning in the Learning Society: How Can the Barriers between Different Learning Spaces Be Surmounted, and How Can the Gap between Learning inside and outside Schools Be Bridged?

    ERIC Educational Resources Information Center

    Illeris, Knud

    2009-01-01

    For more than a century learning psychology has dealt with the so-called transfer problem: that what has been learned in one context often can be difficult to recall and apply in a different context. This article, building on many years' theoretical and practical work in the field, starts by defining five main learning spaces in contemporary…

  9. Results of heat transfer tests of an 0.0175-scale space shuttle vehicle model 22 OTS in the NASA-Ames 3.5-foot hypersonic wind tunnel (IH3), volume 3

    NASA Technical Reports Server (NTRS)

    Foster, T. F.; Lockman, W. K.

    1975-01-01

    Heat-transfer data for the 0.0175-scale space shuttle vehicle 3 are presented, and interference heating effects were investigated by a model build-up technique of the orbiter. The test program was conducted at Mach 5.3 for nominal free-stream Reynolds number per foot values of 1,500,000 and 5,000,000.

  10. State space approach to unsteady magnetohydrodynamics natural convection heat and mass transfer through a porous medium saturated with a viscoelastic fluid

    NASA Astrophysics Data System (ADS)

    Ezzat, M. A.; El-Bary, A. A.; Hatem, A. S.

    2014-07-01

    A technique of the state space approach and the inversion of the Laplace transform method are applied to dimensionless equations of an unsteady one-dimensional boundary-layer flow due to heat and mass transfer through a porous medium saturated with a viscoelastic fluid bounded by an infinite vertical plate in the presence of a uniform magnetic field is described. Complete analytical solutions for the temperature, concentration, velocity, and induced magnetic and electric fields are presented. The inversion of the Laplace transforms is carried out by using a numerical approach. The proposed method is used to solve two problems: boundary-layer flow in a viscoelastic fluid near a vertical wall subjected to the initial conditions of a stepwise temperature and concentration and viscoelastic fluid flow between two vertical walls. The solutions are found to be dependent on the governing parameters including the Prandtl number, the Schmidt number, the Grashof number, reaction rate coefficient, viscoelastic parameter, and permeability of the porous medium. Effects of these major parameters on the transport behavior are investigated methodically, and typical results are illustrated to reveal the tendency of the solutions. Representative results are presented for the velocity, temperature, concentration, and induced magnetic and electric field distributions, as well as the local skin-friction coefficient and the local Nusselt and Sherwood numbers.

  11. Dark signal correction for a lukecold frame-transfer CCD. New method and application to the solar imager of the PICARD space mission

    NASA Astrophysics Data System (ADS)

    Hochedez, J.-F.; Timmermans, C.; Hauchecorne, A.; Meftah, M.

    2014-01-01

    Context. Astrophysical observations must be corrected for their imperfections of instrumental origin. When charge-coupled devices (CCDs) are used, their dark signal is one such hindrance. In their pristine state, most CCD pixels are cool, that is, they exhibit a low quasi-uniform dark current, which can be estimated and corrected for. In space, after having been hit by an energetic particle, pixels can turn hot, viz. they start delivering excessive, less predictable, dark current. The hot pixels therefore need to be flagged so that a subsequent analysis may ignore them. Aims: The image data of the PICARD-SODISM solar telescope require dark signal correction and hot pixel identification. Its E2V 42-80 CCD operates at -7.2 °C and has a frame-transfer architecture. Both image and memory zones thus accumulate dark current during integration and readout time, respectively. These two components must be separated in order to estimate the dark signal for any given observation. This is the main purpose of the dark signal model presented in this paper. Methods: The dark signal time-series of every pixel was processed by the unbalanced Haar technique to timestamp when its dark signal changed significantly. In-between these instants, the two components were assumed to be constant, and a robust linear regression, with respect to integration time, provides first estimates and a quality coefficient. The latter serves to assign definitive estimates for this pixel and that period. Results: Our model is part of the SODISM Level 1 data production scheme. To confirm its reliability, we verified on dark frames that it leaves a negligible residual bias (5 e-) and generates a small rms error (25 e- rms). We also examined the distribution of the image zone dark current. The cool pixel level is found to be 4.0 e- pxl-1 s-1, in agreement with the predicted value. The emergence rate of hot pixels was investigated as well. It yields a threshold criterion at 50 e- pxl-1 s-1. The growth rate

  12. Space America's commercial space program

    NASA Technical Reports Server (NTRS)

    Macleod, N. H.

    1984-01-01

    Space America prepared a private sector land observing space system which includes a sensor system with eight spectral channels configured for stereoscopic data acquisition of four stereo pairs, a spacecraft bus with active three-axis stabilization, a ground station for data acquisition, preprocessing and retransmission. The land observing system is a component of Space America's end-to-end system for Earth resources management, monitoring and exploration. In the context of the Federal Government's program of commercialization of the US land remote sensing program, Space America's space system is characteristic of US industry's use of advanced technology and of commercial, entrepreneurial management. Well before the issuance of the Request for Proposals for Transfer of the United States Land Remote Sensing Program to the Private Sector by the US Department of Commerce, Space Services, Inc., the managing venturer of Space America, used private funds to develop and manage its sub-orbital launch of its Conestoga launch vehicle.

  13. Heat transfer tests of a 0.006-scale thin skin space shuttle model (50-0, 41-T) in the Langley Research Center nitrogen tunnel at Mach 19 (IH19)

    NASA Technical Reports Server (NTRS)

    Walstad, D. G.

    1975-01-01

    Data are presented from heat transfer tests on an 0.0006-scale space shuttle vehicle in the Langley Research Center Nitrogen Tunnel. The purpose of this test was to obtain ascent heating data at a high hypersonic Mach number. Configurations tested were integrated orbiter and external tank, orbiter alone, and external tank alone. All configurations were tested with and without boundary layer transition. Testing was conducted at a Mach number of 19, a Reynolds number of 0.5 million per foot, and angles of attack of 0, + or - 5, and + or - 10 degrees. Heat transfer data was obtained from 77 orbiter and 90 external tank iron-constantan thermocouples.

  14. Technology transfer within the government

    NASA Technical Reports Server (NTRS)

    Christensen, Carissa Bryce

    1992-01-01

    The report of a workshop panel concerned with technology transfer within the government is presented. The suggested subtopics for the panel were as follows: (1) transfer from non-NASA U.S. government technology developers to NASA space missions/programs; and (2) transfer from NASA to other U.S. government civil space mission programs. Two presentations were made to the panel: Roles/Value of Early Strategic Planning Within the Space Exploration Initiative (SEI) to Facilitate Later Technology Transfer To and From Industry; and NOAA Satellite Programs and Technology Requirements. The panel discussion addresses the following major issues: DOD/NASA cooperation; alternative mechanisms for interagency communication and interactions; current technology transfer relationships among federal research agencies, and strategies for improving this transfer; technology transfer mechanisms appropriate to intragovernment transfer; the importance of industry as a technology transfer conduit; and measures of merit.

  15. Heat transfer system

    DOEpatents

    McGuire, Joseph C.

    1982-01-01

    A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  16. Heat transfer system

    DOEpatents

    Not Available

    1980-03-07

    A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

  17. Heat transfer tests of an 0.006-scale thin skin space shuttle thermocouple model (41-0) in the Langley Research Center variable density tunnel at M equals 8 (OH13)

    NASA Technical Reports Server (NTRS)

    Walstad, D. G.

    1974-01-01

    Orbiter entry heating distributions were obtained, and phase change paint data was correlated with thermocouple data during a program of heat transfer testing on a 0.006 scale space shuttle orbiter vehicle. The orbiter was tested at 0, 30, and 35 degrees angle of attack at Reynolds numbers of 1, 2, 3, 4, and 6 million per foot. Temperature data were obtained from a total of 57 thermocouples.

  18. Data report for tests on the heat transfer effects of the 0.0175-scale Rockwell International Space Shuttle Vehicle model 22-OT in the AEDC 50-inch B wind tunnel (OH4B), volume 3

    NASA Technical Reports Server (NTRS)

    Foster, T. F.; Grifall, W. J.; Martindale, W.

    1975-01-01

    Results of wind tunnel heat transfer tests of 0.0175-scale Rockwell International Space Shuttle Vehicle configurations for orbiter alone, tank alone, and orbiter plus external tank are presented. Body flap shielding of SSME's during simulated entry was also investigated. The tests were conducted at Mach 8 for thirteen Reynolds number per foot values ranging from 0.5 million to 3.72 million.

  19. Results of heat transfer tests of an 0.0175-scale space shuttle vehicle model 22 OTS in the NASA-Ames 3.5 foot hypersonic wind tunnel (IH3), volume 1

    NASA Technical Reports Server (NTRS)

    Foster, T. F.; Lockman, W. K.

    1975-01-01

    Heat transfer data for the 0.0175-scale space shuttle vehicle 3 are presented. Interference heating effects were investigated by a model build-up technique of orbiter alone, tank alone, second, and first stage configurations. The test program was conducted in the NASA-Ames 3.5-foot hypersonic wind tunnel at Mach 5.3 for nominal free stream Reynolds number per foot values of 1.5, and 5.0 million.

  20. Space Commercialization

    NASA Technical Reports Server (NTRS)

    Martin, Gary L.

    2011-01-01

    A robust and competitive commercial space sector is vital to continued progress in space. The United States is committed to encouraging and facilitating the growth of a U.S. commercial space sector that supports U.S. needs, is globally competitive, and advances U.S. leadership in the generation of new markets and innovation-driven entrepreneurship. Energize competitive domestic industries to participate in global markets and advance the development of: satellite manufacturing; satellite-based services; space launch; terrestrial applications; and increased entrepreneurship. Purchase and use commercial space capabilities and services to the maximum practical extent Actively explore the use of inventive, nontraditional arrangements for acquiring commercial space goods and services to meet United States Government requirements, including measures such as public-private partnerships, . Refrain from conducting United States Government space activities that preclude, discourage, or compete with U.S. commercial space activities. Pursue potential opportunities for transferring routine, operational space functions to the commercial space sector where beneficial and cost-effective.

  1. Space shuttle: Heat transfer investigation of the McDonnell-Douglas delta wing orbiter at a nominal Mach number of 10.5

    NASA Technical Reports Server (NTRS)

    Eaves, R. H.; Buchanan, T. D.

    1972-01-01

    Heat transfer tests for the delta wing orbiter were conducted in a hypervelocity wind tunnel. A 1.1 percent scale model was tested at a Mach number of approximately 10.5 over an angle of attack range from 10 to 60 degrees over a length Reynolds number range from 5 times 10 to the 6th power to 24 times 10 to the 6th power. Heat transfer results were obtained from model surface heat gage measurements and thermographic phosphor paint. Limited pressure measurements were obtained.

  2. Shock interference heat transfer to tank configurations mated to a straight-wing space shuttle orbiter at Mach number 10.3. [investigated in a Langley hypersonic wind tunnel

    NASA Technical Reports Server (NTRS)

    Crawford, D. H.

    1976-01-01

    Heat transfer was measured on a space shuttle-tank configuration with no mated orbiter in place and with the orbiter in 10 different mated positions. The orbiter-tank combination was tested at angles of attack of 0 deg and 5 deg, at a Mach number of 10.3, and at a free-stream Reynolds number of one million based on the length of the tank. Comparison of interference heat transfer with no-interference heat transfer shows that shock interference can increase the heat transfer to the tank by two orders of magnitude along the ray adjacent to the orbiter and can cause high temperature gradients along the tank skin. The relative axial location of the two mated vehicles determined the location of the sharp peaks of extreme heating as well as their magnitude. The other control variables (the angle of attack, the gap, and the cross-section shape) had significant effects that were not as consistent or as extreme.

  3. Space Microbiology

    PubMed Central

    Horneck, Gerda; Klaus, David M.; Mancinelli, Rocco L.

    2010-01-01

    Summary: The responses of microorganisms (viruses, bacterial cells, bacterial and fungal spores, and lichens) to selected factors of space (microgravity, galactic cosmic radiation, solar UV radiation, and space vacuum) were determined in space and laboratory simulation experiments. In general, microorganisms tend to thrive in the space flight environment in terms of enhanced growth parameters and a demonstrated ability to proliferate in the presence of normally inhibitory levels of antibiotics. The mechanisms responsible for the observed biological responses, however, are not yet fully understood. A hypothesized interaction of microgravity with radiation-induced DNA repair processes was experimentally refuted. The survival of microorganisms in outer space was investigated to tackle questions on the upper boundary of the biosphere and on the likelihood of interplanetary transport of microorganisms. It was found that extraterrestrial solar UV radiation was the most deleterious factor of space. Among all organisms tested, only lichens (Rhizocarpon geographicum and Xanthoria elegans) maintained full viability after 2 weeks in outer space, whereas all other test systems were inactivated by orders of magnitude. Using optical filters and spores of Bacillus subtilis as a biological UV dosimeter, it was found that the current ozone layer reduces the biological effectiveness of solar UV by 3 orders of magnitude. If shielded against solar UV, spores of B. subtilis were capable of surviving in space for up to 6 years, especially if embedded in clay or meteorite powder (artificial meteorites). The data support the likelihood of interplanetary transfer of microorganisms within meteorites, the so-called lithopanspermia hypothesis. PMID:20197502

  4. Heat transfer tests of an 0.006-scale thin-skin space shuttle model (41-OTS) in the Ames 3.5-foot HWT at M equals 5.3 (IH15)

    NASA Technical Reports Server (NTRS)

    Walstad, D. G.; Lockman, W. K.

    1974-01-01

    Data obtained from heat transfer tests of an 0.006-scale space shuttle vehicle in a 3.5-foot hypersonic wind tunnel are presented. The purpose of these tests was to parametrically investigate the ascent heating of the integrated vehicle. Configurations tested were complete for integrated vehicle, orbiter alone, external tank alone, and SRB alone. All configurations were tested with and without transition grit. Testing was conducted at a Mach number of 5.3, and at Reynolds numbers of 2 and 5 million per foot. The angle of attack range varied from 0 to minus 5 degress, execpt for SRB alone, which was tested from minus 5 to 90 degrees. Heat transfer data were obtained from 223 iron-constantan thermocouples attached to thin-skin stainless steel inserts.

  5. Heat transfer tests of an 0.006-scale thin-skin space shuttle thermocouple model (41-OTS) in the Langley Research Center unitary plan wind tunnel at M equals 3.7 (IH16)

    NASA Technical Reports Server (NTRS)

    Walstad, D. G.

    1975-01-01

    The results are presented of supersonic heat transfer tests performed on the .006 scale space shuttle vehicle model (41-OTS) in the Langley Research Center Unitary Plan Wind Tunnel. These tests were conducted to parametrically investigate ascent heating of the integrated vehicle and its components. The tests were conducted at a nominal Mach number of 3.7 and Reynolds numbers per foot of 2 and 5 million. The model configurations investigated were the integrated vehicle and each component alone (i.e. orbiter, tank and SRB). All the configurations were run with and without transition strips and through an angle of attack range of 0 deg to minus 5 deg with the exception of the SRB which was tested through an angle of attack range of minus 5 deg to 90 deg. The heat transfer data were obtained from 223 iron constantan thermocouples attached to stainless steel thin-skin areas of the model.

  6. Technology transfer within the government

    NASA Technical Reports Server (NTRS)

    Russell, John

    1992-01-01

    The report of a workshop panel concerned with technology transfer within the government is presented. The presentation is made in vugraph form. The assigned subtopic for this panel are as follows: (1) transfer from non-NASA US government technology developers to NASA space missions/programs; and (2) transfer from NASA to other US government space mission programs. A specific area of inquiry was Technology Maturation Milestones. Three areas were investigated: technology development; advanced development; and flight hardware development.

  7. Results of heat transfer tests of an 0.0175-scale space shuttle vehicle model 22 OTS in the NASA-Ames 3.5-foot hypersonic wind tunnel (IH3), volume 4

    NASA Technical Reports Server (NTRS)

    Foster, T. F.; Lockman, W. K.

    1975-01-01

    Heat-transfer data for the 0.0175-scale Space Shuttle Vehicle 3 are presented. Interference heating effects were investigated by a model build-up technique of Orbiter alone, tank alone, second, and first stage configurations. The test program was conducted in the NASA-Ames 3.5-Foot Hypersonic Wind Tunnel at Mach 5.3 for nominal free-stream Reynolds number per foot values of 1.5 x 1,000,000 and 5.0 x 1,000,000.

  8. Base pressure and heat transfer tests of the 0.0225-scale space shuttle plume simulation model (19-OTS) in yawed flight conditions in the NASA-Lewis 10x10-foot supersonic wind tunnel (test IH83)

    NASA Technical Reports Server (NTRS)

    Foust, J. W.

    1979-01-01

    Wind tunnel tests were performed to determine pressures, heat transfer rates, and gas recovery temperatures in the base region of a rocket firing model of the space shuttle integrated vehicle during simulated yawed flight conditions. First and second stage flight of the space shuttle were simulated by firing the main engines in conjunction with the SRB rocket motors or only the SSME's into the continuous tunnel airstream. For the correct rocket plume environment, the simulated altitude pressures were halved to maintain the rocket chamber/altitude pressure ratio. Tunnel freestream Mach numbers from 2.2 to 3.5 were simulated over an altitude range of 60 to 130 thousand feet with varying angle of attack, yaw angle, nozzle gimbal angle and SRB chamber pressure. Gas recovery temperature data derived from nine gas temperature probe runs are presented. The model configuration, instrumentation, test procedures, and data reduction are described.

  9. Station Robotics Testing at Johnson Space Center

    NASA Video Gallery

    At the Space Vehicle Mockup Facility at Johnson Space Center, NASA tests the Japanese Experiment Module ORU Transfer Interface, or JOTI. This device would allow astronauts to transfer orbital repla...

  10. Orbital Fluid Transfer System

    NASA Technical Reports Server (NTRS)

    Johnston, A. S., (Nick); Ryder, Mel; Tyler, Tony R.

    1998-01-01

    An automated fluid and power interface system needs to be developed for future space missions which require on orbit consumable replenishment. Current method of fluid transfer require manned vehicles and extravehicular activity. Currently the US does not have an automated capability for consumable transfer on-orbit. This technology would benefit both Space Station and long duration satellites. In order to provide this technology the Automated Fluid Interface System (AFIS) was developed. The AFIS project was an advanced development program aimed at developing a prototype satellite servicer for future space operations. This mechanism could transfer propellants, cryogens, fluids, gasses, electrical power, and communications from a tanker unit to the orbiting satellite. The development of this unit was a cooperative effort between Marshall Space Flight Center in Huntsville, Alabama, and Moog, Inc. in East Aurora, New York. An engineering model was built and underwent substantial development testing at Marshall Space Flight Center (MSFC). While the AFIS is not suitable for spaceflight, testing and evaluation of the AFIS provided significant experience which would be beneficial in building a flight unit. The lessons learned from testing the AFIS provided the foundation for the next generation fluid transfer mechanism, the Orbital Fluid Transfer System (OFTS). The OFTS project was a study contract with MSFC and Moog, Inc. The OFTS was designed for the International Space Station (ISS), but its flexible design could used for long duration satellite missions and other applications. The OFTS was designed to be used after docking. The primary function was to transfer bipropellants and high pressure gases. The other items addressed by this task included propellant storage, hardware integration, safety and control system issues. A new concept for high pressure couplings was also developed. The results of the AFIS testing provided an excellent basis for the OFTS design. The OFTS

  11. Study of methods for applying and enhancing transfer film coatings of polytetrafluoroethylene (PTEE) to Space Shuttle Main Engine (SSME) High Pressure Oxygen Turbo Pump (HPOTP) bearings

    NASA Technical Reports Server (NTRS)

    Kannel, J. W.; Dufrane, K. F.; Zugaro, F. F.

    1981-01-01

    Machines were constructed and evaluated for burnishing polytetrafluoroethylene on balls for use in the high pressure oxygen turbopump (HPOTP). The most positive performance was obtained with single-ball burnishing, but one technique for burnishing three balls simultaneously holds promise. Evaluations of the coatings in a HPOTP bearing of earlier design (employed smaller diameter balls) showed very little life enhancement before high torque and ball and race wear initiated. Other coating techniques, such as molybdenum disulfide combined with PTFE transfer films, hold promise for providing the more durable quantities of solid lubricant needed for the bearings.

  12. In-Space technology experiments program. A high efficiency thermal interface (using condensation heat transfer) between a 2-phase fluid loop and heatpipe radiator: Experiment definition phase

    NASA Astrophysics Data System (ADS)

    Pohner, John A.; Dempsey, Brian P.; Herold, Leroy M.

    1990-07-01

    Space Station elements and advanced military spacecraft will require rejection of tens of kilowatts of waste heat. Large space radiators and two-phase heat transport loops will be required. To minimize radiator size and weight, it is critical to minimize the temperature drop between the heat source and sink. Under an Air Force contract, a unique, high-performance heat exchanger is developed for coupling the radiator to the transport loop. Since fluid flow through the heat exchanger is driven by capillary forces which are easily dominated by gravity forces in ground testing, it is necessary to perform microgravity thermal testing to verify the design. This contract consists of an experiment definition phase leading to a preliminary design and cost estimate for a shuttle-based flight experiment of this heat exchanger design. This program will utilize modified hardware from a ground test program for the heat exchanger.

  13. In-Space technology experiments program. A high efficiency thermal interface (using condensation heat transfer) between a 2-phase fluid loop and heatpipe radiator: Experiment definition phase

    NASA Technical Reports Server (NTRS)

    Pohner, John A.; Dempsey, Brian P.; Herold, Leroy M.

    1990-01-01

    Space Station elements and advanced military spacecraft will require rejection of tens of kilowatts of waste heat. Large space radiators and two-phase heat transport loops will be required. To minimize radiator size and weight, it is critical to minimize the temperature drop between the heat source and sink. Under an Air Force contract, a unique, high-performance heat exchanger is developed for coupling the radiator to the transport loop. Since fluid flow through the heat exchanger is driven by capillary forces which are easily dominated by gravity forces in ground testing, it is necessary to perform microgravity thermal testing to verify the design. This contract consists of an experiment definition phase leading to a preliminary design and cost estimate for a shuttle-based flight experiment of this heat exchanger design. This program will utilize modified hardware from a ground test program for the heat exchanger.

  14. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Entanglement Properties Between Two Spatially Separated Atoms with Cascade Configuration in Free Space

    NASA Astrophysics Data System (ADS)

    Yang, Guo-Hui; Zhang, Jun-Feng; Miao, Xiang-Yang; Zhou, Ling

    2010-03-01

    We investigate the entanglement properties between two identical atoms with cascade configuration through the retarded dipole-dipole interaction in free space when their spatial separation is on the order of radiation wavelength or less. We analyze the function of Hamiltonian induced by dipole-dipole interaction. By solving master equation, we show that the spontaneous emission induce entanglement and destroy entanglement too. We also show the long life time of entanglement within cascade configuration.

  15. Implementation and extension of the impulse transfer function method for future application to the space shuttle project. Volume 2: Program description and user's guide

    NASA Technical Reports Server (NTRS)

    Patterson, G.

    1973-01-01

    The data processing procedures and the computer programs were developed to predict structural responses using the Impulse Transfer Function (ITF) method. There are three major steps in the process: (1) analog-to-digital (A-D) conversion of the test data to produce Phase I digital tapes (2) processing of the Phase I digital tapes to extract ITF's and storing them in a permanent data bank, and (3) predicting structural responses to a set of applied loads. The analog to digital conversion is performed by a standard package which will be described later in terms of the contents of the resulting Phase I digital tape. Two separate computer programs have been developed to perform the digital processing.

  16. ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS: Conformal Invariance and Noether Symmetry, Lie Symmetry of Birkhoffian Systems in Event Space

    NASA Astrophysics Data System (ADS)

    Zhang, Yi

    2010-01-01

    This paper focuses on studying a conformal invariance and a Noether symmetry, a Lie symmetry for a Birkhoffian system in event space. The definitions of the conformal invariance of the system are given. By investigation on the relations between the conformal invariance and the Noether symmetry, the conformal invariance and the Lie symmetry, the expressions of conformal factors of the system under these circumstances are obtained. The Noether conserved quantities and the Hojman conserved quantities directly derived from the conformal invariance are given. Two examples are given to illustrate the application of the results.

  17. Technology Transfer

    NASA Technical Reports Server (NTRS)

    Bullock, Kimberly R.

    1995-01-01

    The development and application of new technologies in the United States has always been important to the economic well being of the country. The National Aeronautics and Space Administration (NASA) has been an important source of these new technologies for almost four decades. Recently, increasing global competition has emphasized the importance of fully utilizing federally funded technologies. Today NASA must meet its mission goals while at the same time, conduct research and development that contributes to securing US economic growth. NASA technologies must be quickly and effectively transferred into commercial products. In order to accomplish this task, NASA has formulated a new way of doing business with the private sector. Emphasis is placed on forming mutually beneficial partnerships between NASA and US industry. New standards have been set in response to the process that increase effectiveness, efficiency, and timely customer response. This summer I have identified potential markets for two NASA inventions: including the Radially Focused Eddy Current Sensor for Characterization of Flaws in Metallic Tubing and the Radiographic Moire. I have also worked to establish a cooperative program with TAG, private industry, and a university known as the TAG/Industry/Academia Program.

  18. Cryogenic transfer options for exploration missions

    NASA Technical Reports Server (NTRS)

    Chato, David J.

    1991-01-01

    The literature of in-space cryogenic transfer is reviewed in order to propose transportation concepts to support the Space Exploration Initiative (SEI). Forty-nine references are listed and key findings are synopsized. An assessment of the current maturity of cryogenic transfer system technology is made. Although the settled transfer technique is the most mature technology, the No-Vent Fill technology is maturing rapidly. Future options for development of cryogenic transfer technology are also discussed.

  19. NASP technology transfer

    NASA Technical Reports Server (NTRS)

    Morris, Charles

    1992-01-01

    It is the stated goal of this program, the National AeroSpace Plane (NASP) program, to develop and then demonstrate the technologies for single-stage-to-orbit flight and hypersonic cruise with airbreathing primary propulsion and horizontal takeoff and landing. This presentation is concerned with technology transfer in the context of the NASP program.

  20. The Successful Transfer of Space Derived Convergent Spray Technology(TM): An Application for Industrial Roof Coatings and Interstate Bridge Repair

    NASA Technical Reports Server (NTRS)

    McMillan, Vernotto

    1999-01-01

    Although the levels of volatile organic compound (VOC) emissions from industrial roof coatings and paint operations have been reduced in recent years, the roof coating partnership was an effort to further reduce VOC emission levels and to also demonstrate the use of reclaimed automobile tire rubber as a filler material in roof coating systems. Different materials and coatings were evaluated and tested before the final selection was used to coat the roofs of two small buildings at NASA's MSFC (Marshall Space Flight Center) during fiscal year 1997. The primary objective of the Bridge repair partnership was to strategically leverage public and private sector funds for the purpose of developing a bridge repair process that was cheaper, better, and faster than conventional methods. It was also, imperative that this process be environmentally friendly and capable of performing under extreme conditions for a period of not less than 2 years.

  1. Implementation and extension of the impulse transfer function method for future application to the space shuttle project. Volume 1: Analysis and correlation studies

    NASA Technical Reports Server (NTRS)

    Mantus, M.; Pardo, H.

    1973-01-01

    Computer programming, data processing, and a correlation study that employed data collected in the first phase test were used to demonstrate that standard test procedures and equipment could be used to collect a significant number of transfer functions from tests of the Lunar Module test article LTA-11. The testing consisted of suspending the vehicle from the apex fittings of the outrigger trusses through a set of air springs to simulate the free-free state. Impulsive loadings were delivered, one at a time, at each of the landing gear's attachment points, in three mutually perpendicular directions; thus a total of 36 impulses were applied to the vehicle. Time histories of each pulse were recorded on magnetic tape along with 40 channels of strain gage response and 28 channels of accelerometer response. Since an automated data processing system was not available, oscillograph playbacks were made of all 2400 time histories as a check on the validity of the data taken. In addition, one channel of instrumentation was processed to determine its response to a set of forcing functions from a prior LTA-11 drop test. This prediction was compared with drop test results as a first measure of accuracy.

  2. Pragmatic Transfer.

    ERIC Educational Resources Information Center

    Kasper, Gabriele

    1992-01-01

    Attempting to clarify the concept of pragmatic transfer, this article proposes as a basic distinction Leech/Thomas' dichotomy of sociopragmatics versus pragmalinguistics, presenting evidence for transfer at both levels. Issues discussed include pragmatic universals in speech act realization, conditions for pragmatic transfer, communicative…

  3. Technology transfer from the viewpoint of a NASA prime contractor

    NASA Technical Reports Server (NTRS)

    Dyer, Gordon

    1992-01-01

    Viewgraphs on technology transfer from the viewpoint of a NASA prime contractor are provided. Technology Transfer Program for Manned Space Systems and the Technology Transfer Program status are addressed.

  4. Simultaneous determination of benzene and phenol in heat transfer fluid by head-space gas chromatography hyphenated with ion mobility spectrometry.

    PubMed

    Criado-García, L; Garrido-Delgado, R; Arce, L; López, F; Peón, R; Valcárcel, M

    2015-11-01

    The quantitative determination of some compounds such as benzene and phenol in a complex matrix by ion mobility spectrometry (IMS) can be a difficult task, due to the influence of other components present in the matrix and the chemical properties of both compounds, such as their high volatility and low proton affinity. Monitoring of these compounds in a heat transfer fluid (HTF) is essential to check the correct working of a thermosolar plant and for safety and environmental reasons. Benzene and phenol, among other compounds, are produced when HTF is exposed to high temperatures in continuous cycles and their presence can decrease the efficiency of HTF. For the first time, a headspace module coupled to a gas chromatography column in combination with an IMS (with a tritium ionization source) has been optimized and fully validated to simultaneously quantify benzene and phenol in HTF. The limit of detection (LOD) and limit of quantification (LOQ) achieved with the method proposed were 0.011 and 0.038 g L(-1) and 0.004 and 0.014 g L(-1) for benzene and phenol respectively. The precision of the method was evaluated in terms of repeatability and reproducibility with all values lower than 9.2% and 13.3%, respectively. Results demonstrated that benzene and phenol were generated in the HTF heating process, and its concentration increased with heating time (approximately 483 h). The average concentration values for benzene and phenol in degraded HTF samples were not significantly different to values obtained using a gas chromatography-flame ionization detector instrument. Therefore, IMS is a promising technique for in-field quality control of HTF in a thermosolar plant due to its speed, versatility, sensitivity and selectivity to quantify these degradation compounds. PMID:26452912

  5. Technology transfer

    NASA Technical Reports Server (NTRS)

    Handley, Thomas

    1992-01-01

    The requirements for a successful technology transfer program and what such a program would look like are discussed. In particular, the issues associated with technology transfer in general, and within the Jet Propulsion Laboratory (JPL) environment specifically are addressed. The section on background sets the stage, identifies the barriers to successful technology transfer, and suggests actions to address the barriers either generally or specifically. The section on technology transfer presents a process with its supporting management plan that is required to ensure a smooth transfer process. Viewgraphs are also included.

  6. Influence of Non-MHD Flutes on the Efficiency of Energy Transfer from the Laser-Produced, ICF and Space Exploding Plasmas to Magnetic Field

    SciTech Connect

    Zakharov, Yuri P.; Antonov, Vladimir M.; Boyarintsev, Eduard L.; Melekhov, Alexandr V.; Posukh, Vitaliy G.; Shaikhislamov, Ildar F.; Nakashima, Hideki; Vchivkov, Konstantin V

    2005-01-15

    The results of <> experiment with quasispherical Laser-produced Plasma Clouds (LPC) expanding into strong (B{sub 0} {approx}10 kG) and uniform magnetic field at KI-1 facility of ILP are presented. Main characteristics and the influence of non-MHD flute instability onto effectiveness of plasma-field interaction were studied especially for the purpose of plasma confinement and the direct conversion of its kinetic energy into magnetic and electric ones (of pick-up coils). A new model of enhanced field penetration into plasma due to Hall-effect in its flutes and under conditions of finite ion Larmor radius is discussed. The data obtained on the current generation by LPC in short-circuited surrounding coils (with total conversion efficiency up to {approx}10%) are compared with the models of ILP and last results of relevant 3D/PIC calculations done at KU. All these results show the opportunities of LPC-experiments to simulate both space exploding plasmas (AMPTE) and MHD-effects of ICF micro-explosions in planned NIF experiments for study Laser Fusion Rocket like a VISTA.

  7. The Pathfinder Chemical Transfer Propulsion Program

    NASA Technical Reports Server (NTRS)

    Hannum, Ned P.; Berkopec, Frank D.; Zurawski, Robert L.

    1989-01-01

    Pathfinder is a research and technology initiative by the National Aeronautics and Space Administration (NASA) intended to strengthen the technology base of the United States civil space program in preparation for future space exploration missions. Pathfinder begins in FY-89. One of the four major thrusts is the Chemical Transfer Propulsion program which will provide the propulsion technology for high performance, liquid oxygen/liquid hydrogen expander cycle engines which are expected to be operated and maintained in space. These advanced engines will enhance or enable a variety of future space exploration missions. The goals and objectives, management, technical plan, and technology transfer for the Chemical Transfer Propulsion element of Pathfinder are described.

  8. System requirements. [Space systems

    SciTech Connect

    Austin, R.E.

    1982-06-01

    Requirements of future space systems, including large space systems, that operate beyond the space shuttle are discussed. Typical functions required of propulsion systems in this operational regime include payload placement, retrieval, observation, servicing, space debris control and support to large space systems. These functional requirements are discussed in conjunction with two classes of propulsion systems: (1) primary or orbit transfer vehicle (OTV) and (2) secondary or systems that generally operate within or relatively near an operational base orbit. Three propulsion system types are described in relation to these requirements: cryogenic OTV, teleoperator maneuvering system and a solar electric OTV.

  9. Multipurpose Cargo Transfer Bag

    NASA Technical Reports Server (NTRS)

    Broyan, James; Baccus, Shelley

    2014-01-01

    The Logistics Reduction (LR) project within the Advanced Exploration Systems (AES) program is tasked with reducing logistical mass and repurposing logistical items. Multipurpose Cargo Transfer Bags (MCTB) have been designed such that they can serve the same purpose as a Cargo Transfer Bag, the suitcase-shaped common logistics carrying bag for Shuttle and the International Space Station. After use as a cargo carrier, a regular CTB becomes trash, whereas the MCTB can be unzipped, unsnapped, and unfolded to be reused. Reuse ideas that have been investigated include partitions, crew quarters, solar radiation storm shelters, acoustic blankets, and forward osmosis water processing.

  10. Transferring Technology to Industry

    NASA Technical Reports Server (NTRS)

    Wolfenbarger, J. Ken

    2006-01-01

    This slide presentation reviews the technology transfer processes in which JPL has been involved to assist in transferring the technology derived from aerospace research and development to industry. California Institute of Technology (CalTech), the organization that runs JPL, is the leading institute in patents for all U.S. universities. There are several mechanisms that are available to JPL to inform industry of these technological advances: (1) a dedicated organization at JPL, National Space Technology Applications (NSTA), (2) Tech Brief Magazine, (3) Spinoff magazine, and (4) JPL publications. There have also been many start-up organizations and businesses from CalTech.

  11. Transportation concepts for space industrialization

    NASA Technical Reports Server (NTRS)

    Murphy, J. T.

    1977-01-01

    Space shuttle and heavy lift launch vehicle concepts are described with attention to transportation cost trends. Chemical (LOX/LH2), nuclear, and electric propulsion systems are considered. Suggested space shuttle projects include the support of manned geosynchronous missions and the transfer of bulk cargo and large-delicate space structures from fabrication/assembly orbits to their operational locations. It is thought that development of the space shuttle will stimulate interest in space industrialization.

  12. Technology transfer

    NASA Technical Reports Server (NTRS)

    Penaranda, Frank E.

    1992-01-01

    The topics are presented in viewgraph form and include the following: international comparison of R&D expenditures in 1989; NASA Technology Transfer Program; NASA Technology Utilization Program thrusts for FY 1992 and FY 1993; National Technology Transfer Network; and NTTC roles.

  13. Autonomous Data Transfer Operations for Missions

    NASA Technical Reports Server (NTRS)

    Repaci, Max; Baker, Paul; Brosi, Fred

    2000-01-01

    Automating the data transfer operation can significantly reduce the cost of moving data from a spacecraft to a location on Earth. Automated data transfer methods have been developed for the terrestrial Internet. However, they often do not apply to the space environment, since in general they are based on assumptions about connectivity that are true on the Internet but not on space links. Automated file transfer protocols have been developed for use over space links that transfer data via store-and-forward of files or segments of files. This paper investigates some of the operational concepts made possible by these protocols.

  14. 14 CFR 21.47 - Transferability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Transferability. 21.47 Section 21.47... transfer, notify in writing the appropriate aircraft certification office. This notification must include... office before such a transfer in a form and manner acceptable to the FAA. This notification must...

  15. Technology Transfer Report

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Since its inception, Goddard has pursued a commitment to technology transfer and commercialization. For every space technology developed, Goddard strives to identify secondary applications. Goddard then provides the technologies, as well as NASA expertise and facilities, to U.S. companies, universities, and government agencies. These efforts are based in Goddard's Technology Commercialization Office. This report presents new technologies, commercialization success stories, and other Technology Commercialization Office activities in 1999.

  16. Space Suit Thermal Dynamics

    NASA Technical Reports Server (NTRS)

    Campbell, Anthony B.; Nair, Satish S.; Miles, John B.; Iovine, John V.; Lin, Chin H.

    1998-01-01

    The present NASA space suit (the Shuttle EMU) is a self-contained environmental control system, providing life support, environmental protection, earth-like mobility, and communications. This study considers the thermal dynamics of the space suit as they relate to astronaut thermal comfort control. A detailed dynamic lumped capacitance thermal model of the present space suit is used to analyze the thermal dynamics of the suit with observations verified using experimental and flight data. Prior to using the model to define performance characteristics and limitations for the space suit, the model is first evaluated and improved. This evaluation includes determining the effect of various model parameters on model performance and quantifying various temperature prediction errors in terms of heat transfer and heat storage. The observations from this study are being utilized in two future design efforts, automatic thermal comfort control design for the present space suit and design of future space suit systems for Space Station, Lunar, and Martian missions.

  17. Pure transfer

    NASA Astrophysics Data System (ADS)

    2014-03-01

    Spectral purity can now be transferred from one laser to another with a very different wavelength at an order of magnitude better than previously achievable. Yann Le Coq spoke to Nature Photonics about the new development.

  18. Space transfer vehicle avionics advanced development needs

    NASA Technical Reports Server (NTRS)

    Huffaker, C. F.

    1990-01-01

    The assessment of preliminary transportation program options for the exploration initiative is underway. The exploration initiative for the Moon and Mars is outlined by mission phases. A typical lunar/Mars outpost technology/advanced development schedule is provided. An aggressive and focused technology development program is needed as early as possible to successfully support these new initiatives. The avionics advanced development needs, plans, laboratory facilities, and benefits from an early start are described.

  19. 14 CFR 414.29 - Safety approval transfer.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 414.29 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION... safety approval or the prospective transferee may request a safety approval transfer. (c) Both the holder and prospective transferee must agree to the transfer. (d) The person requesting the transfer...

  20. Technology Transfer

    NASA Technical Reports Server (NTRS)

    Smith, Nanette R.

    1995-01-01

    The objective of this summer's work was to attempt to enhance Technology Application Group (TAG) ability to measure the outcomes of its efforts to transfer NASA technology. By reviewing existing literature, by explaining the economic principles involved in evaluating the economic impact of technology transfer, and by investigating the LaRC processes our William & Mary team has been able to lead this important discussion. In reviewing the existing literature, we identified many of the metrics that are currently being used in the area of technology transfer. Learning about the LaRC technology transfer processes and the metrics currently used to track the transfer process enabled us to compare other R&D facilities to LaRC. We discuss and diagram impacts of technology transfer in the short run and the long run. Significantly, it serves as the basis for analysis and provides guidance in thinking about what the measurement objectives ought to be. By focusing on the SBIR Program, valuable information regarding the strengths and weaknesses of this LaRC program are to be gained. A survey was developed to ask probing questions regarding SBIR contractors' experience with the program. Specifically we are interested in finding out whether the SBIR Program is accomplishing its mission, if the SBIR companies are providing the needed innovations specified by NASA and to what extent those innovations have led to commercial success. We also developed a survey to ask COTR's, who are NASA employees acting as technical advisors to the SBIR contractors, the same type of questions, evaluating the successes and problems with the SBIR Program as they see it. This survey was developed to be implemented interactively on computer. It is our hope that the statistical and econometric studies that can be done on the data collected from all of these sources will provide insight regarding the direction to take in developing systematic evaluations of programs like the SBIR Program so that they can

  1. In-Space Transportation for Geo Space Solar Satellites

    NASA Technical Reports Server (NTRS)

    Martin, James A.; Donahue, Benjamin B.; Lawrence, Schuyler C.; McClanahan, James A.; Carrington, Connie (Technical Monitor)

    2000-01-01

    Space solar power satellites have the potential to provide abundant quantities of electricity for use on Earth. One concept, the Sun Tower, can be assembled in geostationary orbit from pieces transferred from Earth. The cost of transportation from Earth is one of the major hurdles to space solar power. This study found that a two-stage rocket launch vehicle with autonomous solar-electric transfer can provide the transportation at prices close to the goal of $800/kg

  2. Space technology research plans

    NASA Technical Reports Server (NTRS)

    Hook, W. Ray

    1992-01-01

    Development of new technologies is the primary purpose of the Office of Aeronautics and Space Technology (OAST). OAST's mission includes the following two goals: (1) to conduct research to provide fundamental understanding, develop advanced technology and promote technology transfer to assure U.S. preeminence in aeronautics and to enhance and/or enable future civil space missions: and (2) to provide unique facilities and technical expertise to support national aerospace needs. OAST includes both NASA Headquarters operations as well as programmatic and institutional management of the Ames Research Center, the Langley Research Center and the Lewis Research Center. In addition. a considerable portion of OAST's Space R&T Program is conducted through the flight and science program field centers of NASA. Within OAST, the Space Technology Directorate is responsible for the planning and implementation of the NASA Space Research and Technology Program. The Space Technology Directorate's mission is 'to assure that OAST shall provide technology for future civil space missions and provide a base of research and technology capabilities to serve all national space goals.' Accomplishing this mission entails the following objectives: y Identify, develop, validate and transfer technology to: (1) increase mission safety and reliability; (2) reduce flight program development and operations costs; (3) enhance mission performance; and (4) enable new missions. Provide the capability to: (1) advance technology in critical disciplines; and (2) respond to unanticipated mission needs. In-space experiments are an integral part of OAST's program and provides for experimental studies, development and support for in-space flight research and validation of advanced space technologies. Conducting technology experiments in space is a valuable and cost effective way to introduce advanced technologies into flight programs. These flight experiments support both the R&T base and the focussed programs

  3. [Technology Transfer.

    ERIC Educational Resources Information Center

    Latker, Norman J.

    Some authorities on technolgoy transfer feel that industry is not fully capitalizing on the inventive output of universities and nonprofit organizations. From the point of view of the government, the stakes are high. The magnitude of federal support of research and development in these organizations demands evidence of useful results if it is to…

  4. 14 CFR 435.13 - Transfer of a reentry license.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Transfer of a reentry license. 435.13 Section 435.13 Aeronautics and Space COMMERCIAL SPACE TRANSPORTATION, FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION LICENSING REENTRY OF A REENTRY VEHICLE OTHER THAN A REUSABLE LAUNCH VEHICLE (RLV) General § 435.13 Transfer of a...

  5. Comprehensive report of aeropropulsion, space propulsion, space power, and space science applications of the Lewis Research Center

    NASA Technical Reports Server (NTRS)

    1988-01-01

    The research activities of the Lewis Research Center for 1988 are summarized. The projects included are within basic and applied technical disciplines essential to aeropropulsion, space propulsion, space power, and space science/applications. These disciplines are materials science and technology, structural mechanics, life prediction, internal computational fluid mechanics, heat transfer, instruments and controls, and space electronics.

  6. Space biosynthesis systems

    NASA Technical Reports Server (NTRS)

    Nyiri, L. K.; Toth, G. M.

    1976-01-01

    Model reactions based on chemical, enzymatic or cellular conversion of D glucose into d gluconic acid are designed to unequivocally define the advantages of microgravity on reaction mechanisms, mass-transfers and separation of organic chemicals and to serve as procedures to test the performance characteristics of space bioprocessing equipment.

  7. Orbital transfer vehicle concept definition and system analysis study. Volume 10: Aerocapture for manned Mars missions

    NASA Technical Reports Server (NTRS)

    Willcockson, W. H.

    1988-01-01

    A manned expedition to Mars has been under consideration as a potential mission for the early 21st century. The necessarily large vehicle requirements have sparked interest in aerocapture as a means of reducing propellant usage. This volume summarizes the work performed to establish concepts and feasibility of such a mission which makes maximum use of aeroassist maneuvers.

  8. Results from a convective heat transfer rate distribution test on a 0.0175 scale model (22-0) of the Rockwell International vehicle 4 space shuttle configuration in the AEDC-VKF tunnel B (OH49B), volume 1

    NASA Technical Reports Server (NTRS)

    Herrera, B. J.

    1976-01-01

    The tests were conducted in a hypersonic wind tunnel at Mach number 8 to investigate reentry mode convective heat--transfer rates to the vehicle 4 shuttle orbiter. The thin skin thermocouple technique was used to obtain the heat transfer rate measurements. A complete set of tabulated data is presented.

  9. Computational fluid dynamics and aerothermodynamics

    NASA Technical Reports Server (NTRS)

    Carlson, Leland A.

    1989-01-01

    The primary objective was the development of nonequilibrium radiation and chemistry models suitable for engineering applications associated with the flow fields about aeroassisted orbital transfer vehicles (AOTVs), the aero-assisted flight experiment vehicle (AFE), and other vehicles operating at superorbital velocities and very high attitudes.

  10. Transfer functions

    NASA Technical Reports Server (NTRS)

    Taback, I.

    1979-01-01

    The vulnerability of electronic equipment to carbon fibers is studied. The effectiveness of interfaces, such as filters, doors, window screens, and cabinets, which affect the concentration, exposure, or deposition of carbon fibers on both (internal and external) sides of the interface is examined. The transfer function of multilayer aluminum mesh, wet and dry, polyurethane foam, and window screen are determined as a function of air velocity. FIlters installed in typical traffic control boxes and air conditioners are also considered.

  11. Thermal flux transfer system

    NASA Technical Reports Server (NTRS)

    Freggens, R. A. (Inventor)

    1973-01-01

    A thermal flux transfer system for use in maintaining the thrust chamber of an operative reaction motor at given temperatures is described. The system is characterized by an hermetically sealed chamber surrounding a thrust chamber to be cooled, with a plurality of parallel, longitudinally spaced, disk-shaped wick members formed of a metallic mesh and employed in delivering a working fluid, in its liquid state, radially toward the thrust chamber and delivering the working fluid, in its vapor state, away from the nozzle for effecting a cooling of the nozzle, in accordance with known principles of an operating heat pipe.

  12. Olympic torch transfer

    NASA Technical Reports Server (NTRS)

    1996-01-01

    KSC Shuttle Operations Manager Loren J. Shriver (right) transfers the Olympic flame to KSC runner Joanne Maceo's torch at the top of Launch Pad 39A after he carried the Olympic torch to the top of the pad as his contribution to the July 7, 1996 KSC Olympic torch relay effort. Jon Granston of the Atlanta Committee for the Olympic Games (center) witnesses the exchange. Maceo then carried her lit torch down the concrete hard stand of the pad to pass the flame to another of the 20-member KSC runner team that participated in the KSC relay effort. The Olympic torch arrived at KSC at 1:40 p.m. and traveled a 20-mile course to the pad and then out to the KSC visitor Center. The Space Shuttle Atlantis is behind the trio, poised for the STS-79 mission, with will feature the fourth docking of the shuttle with the Russian Mir space station.

  13. Aerobraking orbital transfer vehicle

    NASA Technical Reports Server (NTRS)

    Scott, Carl D. (Inventor); Nagy, Kornel (Inventor); Roberts, Barney B. (Inventor); Ried, Robert C. (Inventor); Kroll, Kenneth R. (Inventor); Gamble, Joe (Inventor)

    1989-01-01

    An aerobraking orbital transfer vehicle which includes an aerobraking device which also serves as a heat shield in the shape of a raked-off elliptic or circular cone with a circular or elliptical base, and with an ellipsoid or other blunt shape nose. The aerobraking device is fitted with a toroid-like skirt and is integral with the support structure of the propulsion system and other systems of the space vehicle. The vehicle is intended to be transported in components to a space station in lower earth orbit where it is assembled for use as a transportation system from low earth orbit to geosynchronous earth orbit and return. Conventional guidance means are included for autonomous flight.

  14. NASA's Chemical Transfer Propulsion Program for Pathfinder

    NASA Technical Reports Server (NTRS)

    Hannum, Ned P.; Berkopec, Frank D.; Zurawski, Robert L.

    1989-01-01

    Pathfinder is a research and technology project, with specific deliverables, initiated by the National Aeronautics and Space Administration (NASA) which will strengthen the technology base of the United States civil space program in preparation for future space exploration missions. Pathfinder begins in Fiscal Year 1989, and is to advance a collection of critical technologies for these missions and ensure technology readiness for future national decisions regarding exploration of the solar system. The four major thrusts of Pathfinder are: surface exploration, in-space operations, humans-in-space, and space transfer. The space transfer thrust will provide the critical technologies needed for transportation to, and return from, the Moon, Mars, and other planets in the solar system, as well as for reliable and cost-effective Earth-orbit operations. A key element of this thrust is the Chemical Transfer Propulsion program which will provide the propulsion technology for high performance, liquid oxygen/liquid hydrogen expander cycle engines which may be operated and maintained in space. Described here are the program overview including the goals and objectives, management, technical plan, and technology transfer for the Chemical Transfer Propulsion element of Pathfinder.

  15. Space Discovery.

    ERIC Educational Resources Information Center

    Blackman, Joan

    1998-01-01

    Describes one teacher's experience taking Space Discovery courses that were sponsored by the United States Space Foundation (USSF). These courses examine the history of space science, theory of orbits and rocketry, the effects of living in outer space on humans, and space weather. (DDR)

  16. Space Shuttle

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The space shuttle flight system and mission profile are briefly described. Emphasis is placed on the economic and social benefits of the space transportation system. The space shuttle vehicle is described in detail.

  17. Technology transfer to the broader economy

    NASA Technical Reports Server (NTRS)

    Dyer, Gordon; Clark, Robert

    1992-01-01

    Approaches to the transfer of government-funded civil space technology to the broader commercial economy were addressed by Working Panel no. 4. Some of the problems related to current strategies for technology transfer and recommendations for new approaches are described in outline form.

  18. Energy transfer mechanisms between molecules

    NASA Technical Reports Server (NTRS)

    Meador, W. E.

    1985-01-01

    Reliable rate coefficients for energy transfer and relaxation phenomena are needed in order to do the theoretical modeling which is necessary for accomplishing the following objectives: understanding and justifying proposed laser systems, determining limitations, identifying control parameters, and scaling to space-power requirements. Modeling also establishes the criteria to be followed for lasant selection. Lack of knowledge of rate coefficients is invariably the biggest obstacle to successful modeling. Existing theoretical methods are discussed, sources of error are identified, and transfer laser criteria suggested by the theory are listed. The emphasis is on vibrational-vibrational (V-V) energy transfer caused by both short range and long range interactions between molecules. Special attention is given to the importance of near-resonant collisional and dipole-dipole transfer. A technique is proposed for significantly improving the theoretical predictions of rate coefficients.

  19. Space Station

    NASA Technical Reports Server (NTRS)

    Anderton, D. A.

    1985-01-01

    The official start of a bold new space program, essential to maintain the United States' leadership in space was signaled by a Presidential directive to move aggressively again into space by proceeding with the development of a space station. Development concepts for a permanently manned space station are discussed. Reasons for establishing an inhabited space station are given. Cost estimates and timetables are also cited.

  20. Technology transfer initiatives

    NASA Technical Reports Server (NTRS)

    Mccain, Wayne; Schroer, Bernard J.; Ziemke, M. Carl

    1994-01-01

    This report summarizes the University of Alabama in Huntsville (UAH) technology transfer activities with the Marshall Space Flight Center (MSFC) for the period of April 1993 through December 1993. Early in 1993, the MSFC/TUO and UAH conceived of the concept of developing stand-alone, integrated data packages on MSFC technology that would serve industrial needs previously determined to be critical. Furthermore, after reviewing over 500 problem statements received by MSFC, it became obvious that many of these requests could be satisfied by a standard type of response. As a result, UAH has developed two critical area response (CAR) packages: CFC (chlorofluorocarbon) replacements and modular manufacturing and simulation. Publicity included news releases, seminars, articles and conference papers. The Huntsville Chamber of Commerce established the Technology Transfer Subcommittee with the charge to identify approaches for the Chamber to assist its members, as well as non-members, access to the technologies at the federal laboratories in North Alabama. The Birmingham Chamber of Commerce has expressed interest in establishing a similar technology transfer program. This report concludes with a section containing a tabulation of the problem statements, including CAR packages, submitted to MSFC from January 1992 through December 1993.

  1. Space station

    NASA Technical Reports Server (NTRS)

    Stewart, Donald F.; Hayes, Judith

    1989-01-01

    The history of American space flight indicates that a space station is the next logical step in the scientific pursuit of greater knowledge of the universe. The Space Station and its complement of space vehicles, developed by NASA, will add new dimensions to an already extensive space program in the United States. The Space Station offers extraordinary benefits for a comparatively modest investment (currently estimated at one-ninth the cost of the Apollo Program). The station will provide a permanent multipurpose facility in orbit necessary for the expansion of space science and technology. It will enable significant advancements in life sciences research, satellite communications, astronomy, and materials processing. Eventually, the station will function in support of the commercialization and industrialization of space. Also, as a prerequisite to manned interplanetary exploration, the long-duration space flights typical of Space Station missions will provide the essential life sciences research to allow progressively longer human staytime in space.

  2. Space Power

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Appropriate directions for the applied research and technology programs that will develop space power systems for U.S. future space missions beyond 1995 are explored. Spacecraft power supplies; space stations, space power reactors, solar arrays, thermoelectric generators, energy storage, and communication satellites are among the topics discussed.

  3. Themed Space

    ERIC Educational Resources Information Center

    Lynch, Christopher O.

    2010-01-01

    This article presents a classroom activity that introduces students to the concept of themed space. Students learn to think critically about the spaces they encounter on a regular basis by analyzing existing spaces and by working in groups to create their own themed space. This exercise gives students the chance to see the relevance of critical…

  4. Space colonization.

    PubMed

    2002-12-01

    NASA interest in colonization encompasses space tourism; space exploration; space bases in orbit, at L1, on the Moon, or on Mars; in-situ resource utilization; and planetary terraforming. Activities progressed during 2002 in areas such as Mars colonies, hoppers, and biomass; space elevators and construction; and in-situ consumables. PMID:12506926

  5. Manrating orbital transfer vehicle propulsion

    NASA Technical Reports Server (NTRS)

    Cooper, L. P.

    1985-01-01

    The expended capabilities for Orbital Transfer Vehicles (OTV) which will be needed to meet increased payload requirements for transporting materials and men to geosynchronous orbit are discussed. The requirement to provide manrating offers challenges and opportunities to the propulsion system designers. The propulsion approaches utilized in previous manned space vehicles of the United States are reviewed. The principals of reliability analysis are applied to the Orbit Transfer Vehicle. Propulsion system options are characterized in terms of the test requirements to demonstrate reliability goals and are compared to earlier vehicle approaches.

  6. Radiative transfer in spherical atmospheres

    NASA Technical Reports Server (NTRS)

    Kalkofen, W.; Wehrse, R.

    1984-01-01

    A method for defining spherical model atmospheres in radiative/convective and hydrostatic equilibrium is presented. A finite difference form is found for the transfer equation and a matrix operator is developed as the discrete space analog (in curvilinear coordinates) of a formal integral in plane geometry. Pressure is treated as a function of temperature. Flux conservation is maintained within the energy equation, although the correct luminosity transport must be assigned for any given level of the atmosphere. A perturbed integral operator is used in a complete linearization of the transfer and constraint equations. Finally, techniques for generating stable solutions in economical computer time are discussed.

  7. Space Station fluid resupply

    NASA Technical Reports Server (NTRS)

    Winters, AL

    1990-01-01

    Viewgraphs on space station fluid resupply are presented. Space Station Freedom is resupplied with supercritical O2 and N2 for the ECLSS and USL on a 180 day resupply cycle. Resupply fluids are stored in the subcarriers on station between resupply cycles and transferred to the users as required. ECLSS contingency fluids (O2 and N2) are supplied and stored on station in a gaseous state. Efficiency and flexibility are major design considerations. Subcarrier approach allows multiple manifest combinations. Growth is achieved by adding modular subcarriers.

  8. Protection from space radiation

    SciTech Connect

    Tripathi, R.K.; Wilson, J.W.; Shinn, J.L.

    2000-07-01

    The exposures anticipated for astronauts in the anticipated human exploration and development of space will be significantly higher (both annual and carrier) than for any other occupational group. In addition, the exposures in deep space result largely from galactic cosmic rays for which there is as yet little experience. Some evidence exists indicating that conventional linear energy transfer defined protection quantities (quality factors) may not be appropriate. The authors evaluate their current understanding of radiation protection with laboratory and flight experimental data and discuss recent improvements in interaction models and transport methods.

  9. Protection from Space Radiation

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.; Shinn, J. L.; Singleterry, R. C.; Clowdsley, M. S.; Cucinotta, F. A.; Badhwar, G. D.; Kim, M. Y.; Badavi, F. F.; Heinbockel, J. H.

    2000-01-01

    The exposures anticipated for our astronauts in the anticipated Human Exploration and Development of Space (HEDS) will be significantly higher (both annual and carrier) than any other occupational group. In addition, the exposures in deep space result largely from the Galactic Cosmic Rays (GCR) for which there is as yet little experience. Some evidence exists indicating that conventional linear energy transfer (LET) defined protection quantities (quality factors) may not be appropriate [1,2]. The purpose of this presentation is to evaluate our current understanding of radiation protection with laboratory and flight experimental data and to discuss recent improvements in interaction models and transport methods.

  10. Space prospects. [european space programs

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A strategy for keeping the Common Market's space effort independent of and competitive with NASA and the space shuttle is discussed. Limited financing is the chief obstacle to this. Proposals include an outer space materials processing project and further development of the Ariane rocket. A manned space program is excluded for the foreseeable future.

  11. Frontier orbital symmetry control of intermolecular electron transfer. Final report, September 15, 1988--December 31, 1994

    SciTech Connect

    Stevens, B.

    1997-07-01

    This report discusses the following topics: the recovery of intermolecular transfer parameters from fluorescence quenching in liquids; photoinduced intramolecular electron transfer in flexible donor/space/acceptor systems containing an extended unsaturated spacer; electron transfer sensitized reaction; the recovery of solute and fractal dimensions from electron transfer quenching data; and frontier orbital symmetry control of back electron transfer.

  12. Heat transfer test of an 0.006-scale thin-skin thermocouple space shuttle model (50-0, 41-T) in the NASA-Ames Research Center 3.5-foot hypersonic wind tunnel at Mach 5.3 (IH28), volume 1

    NASA Technical Reports Server (NTRS)

    Cummings, J. W.; Foster, T. F.; Lockman, W. K.

    1976-01-01

    Data obtained from a heat transfer test conducted on an 0.006-scale space shuttle orbiter and external tank in the NASA-Ames Research Center 3.5-foot Hypersonic Wind Tunnel are presented. The purpose of this test was to obtain data under simulated return-to-launch-site abort conditions. Configurations tested were integrated orbiter and external tank, orbiter alone, and external tank alone at angles of attack of 0, + or - 30, + or - 60, + or - 90, and + or - 120 degrees. Runs were conducted at Mach numbers of 5.2 and 5.3 for Reynolds numbers of 1.0 and 4.0 million per foot, respectively. Heat transfer data were obtained from 75 orbiter and 75 external tank iron-constantan thermocouples.

  13. To Preserve the Sense of Earth from Space. A Report of the Panel on the Information Policy Implications of Archiving Satellite Data, regarding the Archiving Requirements of the Proposed Transfer to the Private Section of the U. S. Civil Space Remote-Sensing Satellite Systems.

    ERIC Educational Resources Information Center

    National Commission on Libraries and Information Science, Washington, DC.

    This report presents the results of a 3-month effort to assess the archiving requirements that should be imposed in the event of a transfer of the United States land remote-sensing satellite systems to the private sector. The emphasis is not on judging the desirability of the proposed transfer, but on recommending the requirements that should be…

  14. Space Radar Laboratory photos taken at Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    1994-01-01

    The Space Radar Laboratory-1 (SRL-1) is being transferred from the payload canister transporter into the payload bay of the Space Shuttle Endeavour. It is to be flown on the STS-59 mission. The Kennedy Space Center alternative photo number is KSC-94PC-323 (30392); In the south Level IV stand of the Operations and Checkout Building low bay, the SRL-1 antenna is being placed atop a pallet which holds the antenna electronics. The Kennedy Space Center alternative photo number is KSC-93PC-1493 (30393).

  15. Twin classics: research that always inspires/Twin studies: elder twin relationships; Superfecundated twinning in chimpanzees; Conjoined twinning and embryo transfer; Reduced frequency of in vitro multiples/Professional and human interest: first identical twin renal transplant; Identical triplet wedding; Spanakos twins: boxers; Twins in space; Political twins.

    PubMed

    Segal, Nancy L

    2015-08-01

    Ten classic works in twin research are described. These volumes are rich in data, interpretation, and impact, and contain life history material that adds depth and dimension to the quantitative findings. Next, research on social relationships in older twins, superfecundated twinning in chimpanzees; effects of embryo transfer on conjoined twinning and the reduced frequency of in vitro multiples is reviewed. Finally, there has been considerable public interest surrounding the first identical twin renal transplant, an identical triplet wedding; identical twin boxers, a twin living in space, and a politically active twin pair. PMID:26148718

  16. 14 CFR 1260.69 - Electronic funds transfer payment methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS General Special Conditions § 1260.69 Electronic funds transfer payment methods. Electronic Funds Transfer Payment Methods October 2000 (a) Payments under this grant will be made by...

  17. 14 CFR 1274.931 - Electronic funds transfer payment methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 5 2011-01-01 2010-01-01 true Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS WITH COMMERCIAL FIRMS Other Provisions and Special Conditions § 1274.931 Electronic funds transfer payment methods. Electronic Funds Transfer Payment Methods July 2002 Payments under...

  18. 14 CFR 1260.69 - Electronic funds transfer payment methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS General Special Conditions § 1260.69 Electronic funds transfer payment methods. Electronic Funds Transfer Payment Methods October 2000 (a) Payments under this grant will be made by...

  19. 14 CFR 1274.931 - Electronic funds transfer payment methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Electronic funds transfer payment methods... COOPERATIVE AGREEMENTS WITH COMMERCIAL FIRMS Other Provisions and Special Conditions § 1274.931 Electronic funds transfer payment methods. Electronic Funds Transfer Payment Methods July 2002 Payments under...

  20. Liquid metal heat transfer issues

    SciTech Connect

    Hoffman, H.W.; Yoder, G.L.

    1984-01-01

    An alkali liquid metal cooled nuclear reactor coupled with an alkali metal Rankine cycle provides a practicable option for space systems/missions requiring power in the 1 to 100 MW(e) range. Thermal issues relative to the use of alkali liquid metals for this purpose are identified as these result from the nature of the alkali metal fluid itself, from uncertainties in the available heat transfer correlations, and from design and performance requirements for system components operating in the earth orbital microgravity environment. It is noted that, while these issues require further attention to achieve optimum system performance, none are of such magnitude as to invalidate this particular space power concept.

  1. Shuttle derived atmospheric density model. Part 1: Comparisons of the various ambient atmospheric source data with derived parameters from the first twelve STS entry flights, a data package for AOTV atmospheric development

    NASA Technical Reports Server (NTRS)

    Findlay, J. T.; Kelly, G. M.; Troutman, P. A.

    1984-01-01

    The ambient atmospheric parameter comparisons versus derived values from the first twelve Space Shuttle Orbiter entry flights are presented. Available flights, flight data products, and data sources utilized are reviewed. Comparisons are presented based on remote meteorological measurements as well as two comprehensive models which incorporate latitudinal and seasonal effects. These are the Air Force 1978 Reference Atmosphere and the Marshall Space Flight Center Global Reference Model (GRAM). Atmospheric structure sensible in the Shuttle flight data is shown and discussed. A model for consideration in Aero-assisted Orbital Transfer Vehicle (AOTV) trajectory analysis, proposed to modify the GRAM data to emulate Shuttle experiments.

  2. Heat transfer measurements for Stirling machine cylinders

    NASA Technical Reports Server (NTRS)

    Kornhauser, Alan A.; Kafka, B. C.; Finkbeiner, D. L.; Cantelmi, F. C.

    1994-01-01

    The primary purpose of this study was to measure the effects of inflow-produced heat turbulence on heat transfer in Stirling machine cylinders. A secondary purpose was to provide new experimental information on heat transfer in gas springs without inflow. The apparatus for the experiment consisted of a varying-volume piston-cylinder space connected to a fixed volume space by an orifice. The orifice size could be varied to adjust the level of inflow-produced turbulence, or the orifice plate could be removed completely so as to merge the two spaces into a single gas spring space. Speed, cycle mean pressure, overall volume ratio, and varying volume space clearance ratio could also be adjusted. Volume, pressure in both spaces, and local heat flux at two locations were measured. The pressure and volume measurements were used to calculate area averaged heat flux, heat transfer hysteresis loss, and other heat transfer-related effects. Experiments in the one space arrangement extended the range of previous gas spring tests to lower volume ratio and higher nondimensional speed. The tests corroborated previous results and showed that analytic models for heat transfer and loss based on volume ratio approaching 1 were valid for volume ratios ranging from 1 to 2, a range covering most gas springs in Stirling machines. Data from experiments in the two space arrangement were first analyzed based on lumping the two spaces together and examining total loss and averaged heat transfer as a function of overall nondimensional parameter. Heat transfer and loss were found to be significantly increased by inflow-produced turbulence. These increases could be modeled by appropriate adjustment of empirical coefficients in an existing semi-analytic model. An attempt was made to use an inverse, parameter optimization procedure to find the heat transfer in each of the two spaces. This procedure was successful in retrieving this information from simulated pressure-volume data with artificially

  3. Heat transfer in aerospace propulsion

    NASA Technical Reports Server (NTRS)

    Simoneau, Robert J.; Hendricks, Robert C.; Gladden, Herbert J.

    1988-01-01

    Presented is an overview of heat transfer related research in support of aerospace propulsion, particularly as seen from the perspective of the NASA Lewis Research Center. Aerospace propulsion is defined to cover the full spectrum from conventional aircraft power plants through the Aerospace Plane to space propulsion. The conventional subsonic/supersonic aircraft arena, whether commercial or military, relies on the turbine engine. A key characteristic of turbine engines is that they involve fundamentally unsteady flows which must be properly treated. Space propulsion is characterized by very demanding performance requirements which frequently push systems to their limits and demand tailored designs. The hypersonic flight propulsion systems are subject to severe heat loads and the engine and airframe are truly one entity. The impact of the special demands of each of these aerospace propulsion systems on heat transfer is explored.

  4. Space Shuttle.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The plans for utilizing reusable space shuttles which could replace almost all present expendable launch vehicles are briefly described. Many illustrations are included showing the artists' concepts of various configurations proposed for space shuttles. (PR)

  5. Space Basics

    NASA Technical Reports Server (NTRS)

    Herbert, Dexter (Editor)

    1991-01-01

    In this education video series, 'Liftoff to Learning', astronauts (Bruce Melnick, Thomas Akers, William Shepherd, Robert Cabana, and Richard Richards) describe the historical beginnings of space exploration from the time of Robert H. Goddard (considered the Father of Rocketry), who, in 1929, invented the first propellant rocket, the prototype of modern liquid propellant rockets, up to the modern Space Shuttles. The questions - where is space, what is space, and how do astronauts get to, stay in, and come back from space are answered through historical footage, computer graphics, and animation. The space environment effects, temperature effects, and gravitational effects on the launching, orbiting, and descent of the Shuttles are discussed. Included is historical still photos and film footage of past space programs and space vehicles.

  6. Heat transfer probe

    DOEpatents

    Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff

    2006-10-10

    Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.

  7. Space medicine

    NASA Technical Reports Server (NTRS)

    Johnson, P. C., Jr.

    1984-01-01

    The medical aspects of space flight are briefly discussed. The problems of space adaptation syndrome, commonly known as space sickness, are described, and its cause is shown. The adaptation of the cardiovascular system to weightlessness, the problems of radiation in space, atrophy of bones and muscles, and loss of blood volume are addressed. The difficulties associated with the reexperience of gravity on return to earth are briefly considered.

  8. Space Construction

    NASA Technical Reports Server (NTRS)

    Hagaman, Jane A. (Editor)

    1987-01-01

    The purpose was to present to the aerospace community an in-depth review of Experimental Assembly of Structures on EVA (EASE)/Assembly Concept for Construction of Erectable Space Structures (ACCESS) space flight experiments and to present the status of activities regarding future space flight experiments and accompanying technology developments that will demonstrate the capability of on-orbit construction required for the Space Station.

  9. Generic Propellants Transfer Unit (GPTU)

    NASA Technical Reports Server (NTRS)

    Cook, Christopher A.

    1992-01-01

    The Generic Propellants Transfer Unit (GPTU) is being designed to support spacecraft liquid propellant operations at the Kennedy Space Center (KSC) and Eastern Test Range (ETR). The GPTU will have a 500 gallon capacity and be Department Of Transportation (DOT) approved for over-the-road transportation of hypergolic propellants. The use of these containers will allow the users to increase efficiency and reduce the following costs: design/construction, transportation (to/from the launch site), propellant transfer operations, and decontamination operations. The user also acquires the flexibility of transporting to an offsite location for processing or storage without obtaining special exemptions or permits. These containers will incorporate their own quantity gaging and temperature sensing systems, and be integrated onto a transport trailer which contains work platforms and a fluid transfer system.

  10. Multipurpose Spaces

    ERIC Educational Resources Information Center

    Gordon, Douglas

    2010-01-01

    The concept of multipurpose spaces in schools is certainly not new. Especially in elementary schools, the combination of cafeteria and auditorium (and sometimes indoor physical activity space as well) is a well-established approach to maximizing the use of school space and a school district's budget. Nonetheless, there continue to be refinements…

  11. Space Law

    NASA Astrophysics Data System (ADS)

    Hermida, Julian

    2006-01-01

    This chapter examines the salient characteristics of Space Law. It analyzes the origins and evolution of Space Law, its main international principles, and some current topics of interest to the scientific community: the delimitation of airspace and outer space, intellectual property, and criminal responsibility.

  12. Space Weather

    NASA Technical Reports Server (NTRS)

    Gallagher, Dennis L.

    2010-01-01

    This video provides a narrated exploration of the history and affects of space weather. It includes information the earth's magnetic field, solar radiation, magnetic storms, and how solar winds affect electronics on earth, with specific information on how space weather affects space exploration in the future.

  13. Trends in Technology Transfer.

    ERIC Educational Resources Information Center

    Starnick, Jurgen

    1988-01-01

    Various forms of technology transfer in Europe and North America are discussed including research contracts, cooperative research centers, and personnel transfer. Examples of approaches to technology transfer are given and the establishment of personnel transfer is discussed. Preconditions for successful technology transfer in the future are…

  14. Mars transfer vehicle studies

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon

    1993-01-01

    Earth-to-Mars distances vary from 60 to 400 million kilometers over a 14-year cycle. This complicates Mars mission design as a function of calendar time. Stay times at Mars are also strongly driven by opportunities for a return flight path which are within the limits of delta-V associated with practical space vehicles. The biggest difference between Mars and lunar transfer missions is mission time, which grows from a few days for the moon, to as much as a few hundred days for Mars missions. As a result, modules for similarly sized crews must be much larger for Mars missions that for transfer to lunar orbit. Technology challenges for one Mars mission scenario analyzed by Boeing include aerobrakes, propulsion, and life support systems. Mission performance is very sensitive to aerobrake weight fraction and, as a result, there is an incentive to use high performance materials such as advanced composites and thermal protection systems. Lander aerobrake would be used twice (for both planetary capture and descent to the Mars surface), and it would need to survive temperatures up to 3500 degrees.

  15. Mars transfer vehicle studies

    NASA Astrophysics Data System (ADS)

    Woodcock, Gordon

    1993-02-01

    Earth-to-Mars distances vary from 60 to 400 million kilometers over a 14-year cycle. This complicates Mars mission design as a function of calendar time. Stay times at Mars are also strongly driven by opportunities for a return flight path which are within the limits of delta-V associated with practical space vehicles. The biggest difference between Mars and lunar transfer missions is mission time, which grows from a few days for the moon, to as much as a few hundred days for Mars missions. As a result, modules for similarly sized crews must be much larger for Mars missions that for transfer to lunar orbit. Technology challenges for one Mars mission scenario analyzed by Boeing include aerobrakes, propulsion, and life support systems. Mission performance is very sensitive to aerobrake weight fraction and, as a result, there is an incentive to use high performance materials such as advanced composites and thermal protection systems. Lander aerobrake would be used twice (for both planetary capture and descent to the Mars surface), and it would need to survive temperatures up to 3500 degrees.

  16. Spectroradiometry with space telescopes

    NASA Astrophysics Data System (ADS)

    Pauluhn, Anuschka; Huber, Martin C. E.; Smith, Peter L.; Colina, Luis

    2015-12-01

    Radiometry, i.e. measuring the power of electromagnetic radiation—hitherto often referred to as "photometry"—is of fundamental importance in astronomy. We provide an overview of how to achieve a valid laboratory calibration of space telescopes and discuss ways to reliably extend this calibration to the spectroscopic telescope's performance in space. A lot of effort has been, and still is going into radiometric "calibration" of telescopes once they are in space; these methods use celestial primary and transfer standards and are based in part on stellar models. The history of the calibration of the Hubble Space Telescope serves as a platform to review these methods. However, we insist that a true calibration of spectroscopic space telescopes must directly be based on and traceable to laboratory standards, and thus be independent of the observations. This has recently become a well-supported aim, following the discovery of the acceleration of the cosmic expansion by use of type-Ia supernovae, and has led to plans for launching calibration rockets for the visible and infrared spectral range. This is timely, too, because an adequate exploitation of data from present space missions, such as Gaia, and from many current astronomical projects like Euclid and WFIRST demands higher radiometric accuracy than is generally available today. A survey of the calibration of instruments observing from the X-ray to the infrared spectral domains that include instrument- or mission-specific estimates of radiometric accuracies rounds off this review.

  17. Mir Space Station

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This is a view of the Russian Mir Space Station photographed by a crewmember of the second Shuttle/Mir docking mission, STS-74. The image shows: top - Progress supply vehicle, Kvant-1 module, and the Core module; middle left - Spektr module; middle center - Kristall module and Docking module; middle right - Kvant-2 module; and bottom - Soyuz. The Progress was an unmarned, automated version of the Soyuz crew transfer vehicle, designed to resupply the Mir. The Kvant-1 provided research in the physics of galaxies, quasars, and neutron stars by measuring electromagnetic spectra and x-ray emissions. The Core module served as the heart of the space station and contained the primary living and working areas, life support, and power, as well as the main computer, communications, and control equipment. The Spektr module provided Earth observation. It also supported research into biotechnology, life sciences, materials science, and space technologies. American astronauts used the Spektr as their living quarters. A main purpose of the Kristall module was to develop biological and materials production technologies in the space environment. The Docking module made it possible for the Space Shuttle to dock easily with the Mir. Kvant-2 was a scientific and airlock module, providing biological research, Earth observations, and EVA (extravehicular activity) capability. The Soyuz typically ferried three crewmembers to and from the Mir. The journey of the 15-year-old Russian Mir Space Station ended March 23, 2001, as the Mir re-entered the Earth's atmosphere and fell into the south Pacific Ocean.

  18. Heat transfer tests on a 0.01-scale Rockwell configuration 3 space shuttle orbiter and tank (37-OT) in the Calspan 48-inch hypersonic shock tunnel (OH12/IH21), volume 1

    NASA Technical Reports Server (NTRS)

    Kotch, M.

    1975-01-01

    Model information and data are presented from wind tunnel tests conducted on 0.01-scale models of the space shuttle orbiter and external tank. These tests were conducted in a hypersonic shock tunnel to determine heating rates on ascent and reentry configurations at various Reynolds numbers, Mach numbers, and angles of attack.

  19. Creating Unique Research Experiences for two-year College faculty And Students (URECAS): An integrated research and transfer program for two-year college students in the Earth and space sciences

    NASA Astrophysics Data System (ADS)

    Asher, P. M.; Adamec, B.

    2012-12-01

    Nationwide, approximately 17% of all two-year colleges offer geoscience degrees, and the two-year college population is growing rapidly. Although 33% of two-year college students are members of underrepresented minorities, this group earned only 12% of geoscience associate's degrees in 2008. Thus, engaging with two-year colleges represents both a potential rich source of diversity for the field and an area where much work remains to be done. Through the National Science Foundation's Opportunities for Enhancing Diversity in the Geosciences Program, we conducted a workshop at the American Geophysical Union's (AGU) Headquarters in Washington DC in July, 2012. This workshop gathered over fifty participants including two-year college Earth and space science faculty who conduct research with their students, as some of their four-year college partners, members of other scientific organizations, and federal employees working to support Earth and space science education. Our workshop provided the opportunity for two-year college faculty to increase their awareness of existing and successful research programs in the Earth and space sciences, and helped to identify relevant challenges to participation for both students and faculty. Additionally, faculty from four-year Earth and space science programs who have successfully transitioned two-year college students into their programs sparked a discussion of the issues and barriers involved in that process. Outcomes from this workshop include dissemination of best practices for doing student-faculty research in Earth and space sciences at two-year colleges, at nearby four-year campuses, and national summer research programs. Our workshop built on previous efforts to coalesce a community of practice made up of two-year college faculty who conduct research in the Earth and space sciences with their students and those who are interested in partnering with or supporting them. Finally, the planning workshop helped to define the path

  20. Water Innovations and Lessons Learned From Water Recycling in Space

    NASA Technical Reports Server (NTRS)

    Flynn, Michael

    2013-01-01

    This Presentation will cover technology and knowledge transfers from space exploration to earth and the tourism industry, for example, water and air preservation, green buildings and sustainable cities.