Evaluation of Diesel Engine Performance with Intake and Exhaust System Throttling : Volume 2. Appendix 1.

DOT National Transportation Integrated Search

1975-11-01

The appendix to the preceding volume presents the data for the subject diesel engine noise study, including an engine sound power level analysis and sound spectrums showing the effect of intake and exhaust restrictions.

Variable camshaft timing system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butterfield, R.P.; Smith, F.R.

1989-09-05

This patent describes an improvement in a variable camshaft timing system for an internal combustion engine having intake and exhaust valves and a camshaft for each of the intake and exhaust valves, an intake sprocket and an exhaust sprocket keyed to their respective camshaft, only one of the camshafts being directly driven by an engine crankshaft, and a timing chain engaging both sprockets. The improvement comprising a single bracket carrying at least one idler sprocket engaging the timing chain, the bracket being mounted for movement to alter the timing relationship between the intake and exhaust sprockets.

Evaluation of Diesel Engine Performance with Intake and Exhaust System Throttling : Volume 1. Text and Appendixes A through H.

DOT National Transportation Integrated Search

1975-11-01

The diesel engine itself is an important source of diesel powered vehicle noise, and becomes dominant after proper treatment of intake/exhaust and cooling system noise at vehicle speeds below fifty miles per hour. An investigation is reported, in two...

Method and apparatus for reducing cold-phase emissions by utilizing oxygen-enriched intake air

DOEpatents

Poola, Ramesh B.; Sekar, Ramanujam R.; Stork, Kevin C.

1997-01-01

An oxygen-enriched air intake control system for an internal combustion engine includes air directing apparatus to control the air flow into the intake of the engine. During normal operation of the engine, ambient air flowing from an air filter of the engine flows through the air directing apparatus into the intake of the engine. In order to decrease the amount of carbon monoxide (CO) and hydrocarbon (HC) emissions that tend to be produced by the engine during a short period of time after the engine is started, the air directing apparatus diverts for a short period of time following the start up of the engine at least a portion of the ambient air from the air filter through a secondary path. The secondary path includes a selectively permeable membrane through which the diverted portion of the ambient air flows. The selectively permeable membrane separates nitrogen and oxygen from the diverted air so that oxygen enriched air containing from about 23% to 25% oxygen by volume is supplied to the intake of the engine.

30 CFR 36.46 - Explosion tests of intake and exhaust systems.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... 36.46 Section 36.46 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...) Explosion tests shall be made with the engine at rest and with the flammable natural gas-air mixtures in the intake and exhaust systems. In other tests with the flammable mixture in motion, the engine shall be...

30 CFR 36.46 - Explosion tests of intake and exhaust systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... 36.46 Section 36.46 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...) Explosion tests shall be made with the engine at rest and with the flammable natural gas-air mixtures in the intake and exhaust systems. In other tests with the flammable mixture in motion, the engine shall be...

30 CFR 36.46 - Explosion tests of intake and exhaust systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... 36.46 Section 36.46 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...) Explosion tests shall be made with the engine at rest and with the flammable natural gas-air mixtures in the intake and exhaust systems. In other tests with the flammable mixture in motion, the engine shall be...

30 CFR 36.46 - Explosion tests of intake and exhaust systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... 36.46 Section 36.46 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...) Explosion tests shall be made with the engine at rest and with the flammable natural gas-air mixtures in the intake and exhaust systems. In other tests with the flammable mixture in motion, the engine shall be...

30 CFR 36.46 - Explosion tests of intake and exhaust systems.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... 36.46 Section 36.46 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR...) Explosion tests shall be made with the engine at rest and with the flammable natural gas-air mixtures in the intake and exhaust systems. In other tests with the flammable mixture in motion, the engine shall be...

Air Intake Performance of Air Breathing Ion Engines

NASA Astrophysics Data System (ADS)

Fujita, Kazuhisa

The air breathing ion engine (ABIE) is a new type of electric propulsion system which can be used to compensate the aerodynamic drag of the satellite orbiting at extremely low altitudes. In this propulsion system, the low-density atmosphere surrounding the satellite is taken in and used as the propellant of ion engines to reduce the propellant mass for a long operation lifetime. Since feasibility and performance of the ABIE are subject to the compression ratio and the air intake efficiency, a numerical analysis has been conducted by means of the direct-simulation Monte-Carlo method to clarify the characteristics of the air-intake performance in highly rarefied flows. Influences of the flight altitude, the aspect-ratio of the air intake duct, the angle of attack, and the wall conditions are investigated.

The causes of unstable engine idle speed and their solutions

NASA Astrophysics Data System (ADS)

Yang, Fan

2018-06-01

There are many types of engines. The most commonly used engine for automobiles is the internal combustion engine. Internal combustion engines use a four-stroke combustion cycle to convert gasoline into motion. The four-stroke approach, also known as the "Ototo cycle," commemorates Nicklaus Otto, who invented it in 1867. The working cycle of a four-stroke engine consists of four piston strokes, ie, intake stroke, compression stroke, power stroke, and exhaust stroke. This article focuses on the cause of the instability of the four-stroke engine and its solution. There are many reasons for the instability of the engine, so this article will be divided into four areas: intake system, fuel system, ignition system and mechanical structure. Based on the above reasons, the corresponding solution is proposed.

Modeling and Control Systems Design for Air Intake System of Diesel Engines for Improvement of Transient Characteristic

NASA Astrophysics Data System (ADS)

Ejiri, Arata; Sasaki, Jun; Kinoshita, Yusuke; Fujimoto, Junya; Maruyama, Tsugito; Shimotani, Keiji

For the purpose of contributing to global environment protection, several research studies have been conducted involving clean-burning diesel engines. In recent diesel engines with Exhaust Gas Recirculation (EGR) systems and a Variable Nozzle Turbocharger (VNT), mutual interference between EGR and VNT has been noted. Hence, designing and adjusting control of the conventional PID controller is particularly difficult at the transient state in which the engine speed and fuel injection rate change. In this paper, we formulate 1st principal model of air intake system of diesel engines and transform it to control oriented model including an engine steady state model and a transient model. And we propose a model-based control system with the LQR Controller, Saturation Compensator, the Dynamic Feed-forward and Disturbance Observer using a transient model. Using this method, we achieved precise reference tracking and emission reduction in transient mode test with the real engine evaluations.

A linear acoustic model for intake wave dynamics in IC engines

NASA Astrophysics Data System (ADS)

Harrison, M. F.; Stanev, P. T.

2004-01-01

In this paper, a linear acoustic model is described that has proven useful in obtaining a better understanding of the nature of acoustic wave dynamics in the intake system of an internal combustion (IC) engine. The model described has been developed alongside a set of measurements made on a Ricardo E6 single cylinder research engine. The simplified linear acoustic model reported here produces a calculation of the pressure time-history in the port of an IC engine that agrees fairly well with measured data obtained on the engine fitted with a simple intake system. The model has proved useful in identifying the role of pipe resonance in the intake process and has led to the development of a simple hypothesis to explain the structure of the intake pressure time history: the early stages of the intake process are governed by the instantaneous values of the piston velocity and the open area under the valve. Thereafter, resonant wave action dominates the process. The depth of the early depression caused by the moving piston governs the intensity of the wave action that follows. A pressure ratio across the valve that is favourable to inflow is maintained and maximized when the open period of the valve is such to allow at least, but no more than, one complete oscillation of the pressure at its resonant frequency to occur while the valve is open.

System and method for controlling engine knock using electro-hydraulic valve actuation

DOEpatents

Brennan, Daniel G

2013-12-10

A control system for an engine includes a knock control module and a valve control module. The knock control module adjusts a period that one or more of an intake valve and an exhaust valve of a cylinder are open based on engine knock corresponding to the cylinder. The valve control module, based on the adjusted period, controls the one or more of the intake valve and the exhaust valve using one or more hydraulic actuators.

Seismic Analysis of Intake Towers

DTIC Science & Technology

1982-10-01

Experiment Station (WES) under the sponsorship of the Directorate of Civil Works of the Office, Chief of Engineers, U. S. Army. The work was funded under...the structural capacity of the intake S,-tower are contained in Engineer Technical Letter (ETL) 1110-2-265 " Civil Systems Incorporated, "Dynamic...Berkeley, Calif. " ___ 1975. "Earthquake Resistant Design of Intake-Outlet Towers," Journal of the Structural Division_ American Society of Civil

Features of the gas dynamics and local heat transfer in intake system of piston engine with supercharging

NASA Astrophysics Data System (ADS)

Plotnikov, L. V.

2017-09-01

Comparison of experimental research results of gas dynamics and instantaneous local heat transfer in the intake pipes for piston internal combustion engines (ICE) without and with supercharging are presented in the article. Studies were conducted on full-scale experimental setups in terms of gas dynamic nonstationarity, which is characteristic of piston engines. It has been established that the turbocharger installation in a gas-air system of piston internal combustion engine leads to significant differences in the patterns of change in gas-dynamic and heat transfer characteristics of flows. These data can be used in a modernization of piston engines due to installation of a turbocharger or in a development of gas-air systems for piston ICE with supercharging.

Modeling and control of fuel distribution in a dual-fuel internal combustion engine leveraging late intake valve closings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kassa, Mateos; Hall, Carrie; Ickes, Andrew

Advanced internal combustion engines, although generally more efficient than conventional combustion engines, often encounter limitations in multi-cylinder applications due to variations in the combustion process encountered across cylinders and between cycles. This study leverages experimental data from an inline 6-cylinder heavy-duty dual fuel engine equipped with exhaust gas recirculation (EGR), a variable geometry turbocharger, and a fully-flexible variable intake valve actuation system to study cylinder-to-cylinder variations in power production and the underlying uneven fuel distribution that causes these variations. The engine is operated with late intake valve closure timings in a dual-fuel combustion mode in which a high reactivity fuelmore » is directly injected into the cylinders and a low reactivity fuel is port injected into the cylinders. Both dual fuel implementation and late intake valve closing (IVC) timings have been shown to improve thermal efficiency. However, experimental data from this study reveal that when late IVC timings are used on a multi-cylinder dual fuel engine a significant variation in IMEP across cylinders results and as such, leads to efficiency losses. The difference in IMEP between the different cylinders ranges from 9% at an IVC of 570°ATDC to 38% at an IVC of 610°ATDC and indicates an increasingly uneven fuel distribution. These experimental observations along with engine simulation models developed using GT-Power have been used to better understand the distribution of the port injected fuel across cylinders under various operating conditions on such dual fuel engines. This study revealed that the fuel distribution across cylinders in this dual fuel application is significantly affected by changes in the effective compression ratio as determined by the intake valve close timing as well as the design of the intake system (specifically the length of the intake runners). Late intake valve closures allow a portion of the trapped air and port injected fuel to flow back out of the cylinders into the intake manifold. The fuel that is pushed back in the intake manifold is then unevenly redistributed across the cylinders largely due to the dominating direction of the flow in the intake manifold. The effects of IVC as well as the impact of intake runner length on fuel distribution were quantitatively analyzed and a model was developed that can be used to accurately predict the fuel distribution of the port injected fuel at different operating conditions with an average estimation error of 1.5% in cylinder-specific fuel flow.« less

Catalog of selected heavy duty transport energy management models

NASA Technical Reports Server (NTRS)

Colello, R. G.; Boghani, A. B.; Gardella, N. C.; Gott, P. G.; Lee, W. D.; Pollak, E. C.; Teagan, W. P.; Thomas, R. G.; Snyder, C. M.; Wilson, R. P., Jr.

1983-01-01

A catalog of energy management models for heavy duty transport systems powered by diesel engines is presented. The catalog results from a literature survey, supplemented by telephone interviews and mailed questionnaires to discover the major computer models currently used in the transportation industry in the following categories: heavy duty transport systems, which consist of highway (vehicle simulation), marine (ship simulation), rail (locomotive simulation), and pipeline (pumping station simulation); and heavy duty diesel engines, which involve models that match the intake/exhaust system to the engine, fuel efficiency, emissions, combustion chamber shape, fuel injection system, heat transfer, intake/exhaust system, operating performance, and waste heat utilization devices, i.e., turbocharger, bottoming cycle.

30 CFR 7.96 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... diesel engine with an intake system, exhaust system, and a safety shutdown system installed. Dry exhaust.... A system connected to the outlet of the diesel engine which includes, but is not limited to, the... constructed that flame or sparks from the diesel engine cannot propagate an explosion of a flammable mixture...

30 CFR 7.96 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... diesel engine with an intake system, exhaust system, and a safety shutdown system installed. Dry exhaust.... A system connected to the outlet of the diesel engine which includes, but is not limited to, the... constructed that flame or sparks from the diesel engine cannot propagate an explosion of a flammable mixture...

Influence of the single EGR valve usability on development of the charge directed to individual cylinders of an internal combustion engine

NASA Astrophysics Data System (ADS)

Krakowian, Konrad; Kaźmierczak, Andrzej; Górniak, Aleksander; Wróbel, Radosław

2017-11-01

Exhaust gas recirculation systems (EGR), aside to a catalytic converters, are nowadays widely used in piston internal combustion engines to reduce nitrogen oxides (NOx) in the exhaust gas. They are characterized in that a portion of exhaust gases from the exhaust manifold is recirculated (via a condenser), and directed to a particular valve. The valve, depending on the current engine load and speed, doses the appropriate amount of exhaust gas into the exhaust manifold. Moreover, its location has a significant impact on the diverse formation of nitrogen oxides and fumes smokiness from the individual cylinders of the engine, which is a result of uneven propagation of exhaust gas into the channels of the intake manifold. This article contains the results of numerical characterized charges formed in symmetrical intake manifold with a centrally-placed EGR valve. Simulations were performed for the original intake system derived from the two-liter, turbocharged VW diesel engine.

Variable oxygen/nitrogen enriched intake air system for internal combustion engine applications

DOEpatents

Poola, Ramesh B.; Sekar, Ramanujam R.; Cole, Roger L.

1997-01-01

An air supply control system for selectively supplying ambient air, oxygen enriched air and nitrogen enriched air to an intake of an internal combustion engine includes an air mixing chamber that is in fluid communication with the air intake. At least a portion of the ambient air flowing to the mixing chamber is selectively diverted through a secondary path that includes a selectively permeable air separating membrane device due a differential pressure established across the air separating membrane. The permeable membrane device separates a portion of the nitrogen in the ambient air so that oxygen enriched air (permeate) and nitrogen enriched air (retentate) are produced. The oxygen enriched air and the nitrogen enriched air can be selectively supplied to the mixing chamber or expelled to atmosphere. Alternatively, a portion of the nitrogen enriched air can be supplied through another control valve to a monatomic-nitrogen plasma generator device so that atomic nitrogen produced from the nitrogen enriched air can be then injected into the exhaust of the engine. The oxygen enriched air or the nitrogen enriched air becomes mixed with the ambient air in the mixing chamber and then the mixed air is supplied to the intake of the engine. As a result, the air being supplied to the intake of the engine can be regulated with respect to the concentration of oxygen and/or nitrogen.

System and method for engine combustion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sczomak, David P.; Gallon, Robert J.; Solomon, Arun S.

A combustion system for use with one or more cylinder bores of an internal combustion engine includes at least one cylinder head defining first and second intake ports in fluid communication with the one or more cylinder bores. A flap is adjustably connected to the at least one cylinder head. The flap includes a first flap portion cooperating with the first intake port extending from an arm and a second flap portion cooperating with the second intake port extending from the arm and disposed adjacent the first flap portion. A controller in electrical communication with an actuator monitors the conditionmore » of the engine and actuates the flap to position the first and second flap portions between first and second positions to create a first combustion condition and a second combustion condition.« less

Ammonia producing engine utilizing oxygen separation

DOEpatents

Easley, Jr., William Lanier; Coleman, Gerald Nelson [Petersborough, GB; Robel, Wade James [Peoria, IL

2008-12-16

A power system is provided having a power source, a first power source section with a first intake passage and a first exhaust passage, a second power source section with a second intake passage and a second exhaust passage, and an oxygen separator. The second intake passage may be fluidly isolated from the first intake passage.

Afterburning control of internal combustion engine exhaust gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakajima, Y.; Hayashi, Y.; Nagumo, S.I.

1976-08-17

Flow of secondary air into the exhaust system is regulated by diaphragm assembly controlled valves between an air supply and the exhaust system. The diaphragm assemblies respond to vacuum in the intake air system of the engine.

Air intake side secondary air supply system for an internal combustion engine with a duty ratio control operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawanabe, T.; Asakura, M.; Shina, T.

1987-09-01

An air intake side secondary air supply system is described for an internal combustion engine having an air intake passage with a carburetor and an exhaust passage, comprising: an air intake side secondary air supply passage communicating with the air intake passage on the downstream side of the carburetor; an open/close valve disposed in the air intake side secondary air supply passage; an oxygen concentration sensor disposed in the exhaust passage; and detection and control means for detecting whether an air-fuel ratio of mixture to be supplied to the engine is leaner or richer with respect to a target air-fuelmore » ratio through a level of an output signal of the oxygen concentration sensor and for periodically actuating the open/close valve, the detection and control means decreasing a valve open period of the open/close valve within each cyclic period by a first predetermined amount when a detected air-fuel ratio of mixture is leaner than the target air-fuel ratio and increasing the valve open period by a second predetermined amount when the detected air-fuel ratio of mixture is richer than the target air-fuel ratio. The second predetermined amount is different from the first predetermined amount.« less

Optimal hydrojet systems

NASA Astrophysics Data System (ADS)

Ivchenko, V. M.; Prikhodko, N. A.; Grigorev, V. A.

1985-12-01

Problems associated with the development of optimal hydrojet engines and hydrojet systems with minimal irreversible losses are reviewed in the light of recent theoretical and experimental studies. In particular, attention is given to the theory of hydrojet propulsion, the hydrodynamics of supercavitating hydrojet engines, hydrojet engines with distributed water intake, and water-gas ramjets. The discussion also covers water-steam jet engines, experimental equipment and methods for testing hydrojet systems, and the principal applications of hydrojet engines.

HVAC--the importance of clean intake section and dry air filter in cold climate.

PubMed

Hanssen, S O

2004-01-01

HVAC systems, if properly designed, installed, operated and maintained, will improve thermal conditions and air quality indoors. However, the success strongly depends on the design of the system and the quality of the components we use in our HVAC installations. Regrettably, several investigations have revealed that many HVAC installations have a lot of operational and maintenance problems, especially related to moisture, rain and snow entrainment. In short, it seems that too little attention is placed on the design of the intake section, despite the fact that there exists a large number of national and international guidelines and recommendations. This is a serious problem because the air intake is the initial component of the ventilation plant and as such the first line of defense against debris and other outdoor air pollutants. Unfortunately, the design is often an argued compromise between the architect, the civil engineer and the HVAC engineer. In the future, the technical, hygienic and microbiological feature of air intakes must be better ensured in order to avoid the air intake becoming a risk component as regards contamination and indoor air quality. Further, it seems that the magnitude of the problem is not well known, or recognized, by the building designers, engineers and professionals involved in the construction and operation of buildings. This fact needs to be addressed more seriously, because obviously there is a big difference between the idealistic architectonic design, engineering intentions and the real life situation. Several practical recommendations for design and operation of HVAC systems are presented. Following the recommendations will result in less pollution from the HVAC-system and increased indoor environmental quality.

30 CFR 250.610 - Diesel engine air intakes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Diesel engine air intakes. 250.610 Section 250... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines...

30 CFR 250.610 - Diesel engine air intakes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Diesel engine air intakes. 250.610 Section 250... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines...

40 CFR 89.325 - Engine intake air temperature measurement.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made either...

40 CFR 89.325 - Engine intake air temperature measurement.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made either...

40 CFR 89.325 - Engine intake air temperature measurement.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made either...

40 CFR 89.325 - Engine intake air temperature measurement.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 122 cm of the engine. The measurement location must be made either...

The influence of mixture preparation in the intake port on the performance of a spark-ignited four-stroke engine

NASA Astrophysics Data System (ADS)

Daniels, Charles Howard

An experimental technique is developed for evaluating the influence of mixture preparation in the intake port on the performance of a spark ignited engine. The preparation components studied are fuel vapor, droplets, and liquid streams. The fuel in these three distinct forms are produced and varied in a specially designed mixture preparation system, which delivers an air/fuel mixture to a test cylinder of an engine. Incorporated in the preparation system are devices for measuring the flow rates of fuel in these forms. A method of estimating the vapor concentration of a gasoline in the preparation channel by the use of simple temperature measurements is also presented. The effect of these fuel forms on in-cylinder pressure performance and exhaust gas concentrations are investigated in a 1.9 L Ford engine. A matrix of engine operations are studied along with two gasolines of different volatilities. The results of this investigation show that the operation of the engine at low speeds and low manifold absolute pressures is most susceptible to the effects mixture preparation. For those engine operating conditions affected, the results show that by increasing the amount of fuel in liquid stream form, the performance of the engine is generally diminished. In addition, 'equivalent' mixtures resulting from a conventional injector and a pneumatic atomizer in the intake port are identified relative to engine performance.

46 CFR 58.10-5 - Gasoline engine installations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 2 2011-10-01 2011-10-01 false Gasoline engine installations. 58.10-5 Section 58.10-5... MACHINERY AND RELATED SYSTEMS Internal Combustion Engine Installations § 58.10-5 Gasoline engine... drained by a device for automatic return of all drip to engine air intakes. (2) All gasoline engines must...

46 CFR 58.10-5 - Gasoline engine installations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 2 2012-10-01 2012-10-01 false Gasoline engine installations. 58.10-5 Section 58.10-5... MACHINERY AND RELATED SYSTEMS Internal Combustion Engine Installations § 58.10-5 Gasoline engine... drained by a device for automatic return of all drip to engine air intakes. (2) All gasoline engines must...

46 CFR 58.10-5 - Gasoline engine installations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 2 2013-10-01 2013-10-01 false Gasoline engine installations. 58.10-5 Section 58.10-5... MACHINERY AND RELATED SYSTEMS Internal Combustion Engine Installations § 58.10-5 Gasoline engine... drained by a device for automatic return of all drip to engine air intakes. (2) All gasoline engines must...

46 CFR 58.10-5 - Gasoline engine installations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 2 2014-10-01 2014-10-01 false Gasoline engine installations. 58.10-5 Section 58.10-5... MACHINERY AND RELATED SYSTEMS Internal Combustion Engine Installations § 58.10-5 Gasoline engine... drained by a device for automatic return of all drip to engine air intakes. (2) All gasoline engines must...

Mathematical modeling and characteristic analysis for over-under turbine based combined cycle engine

NASA Astrophysics Data System (ADS)

Ma, Jingxue; Chang, Juntao; Ma, Jicheng; Bao, Wen; Yu, Daren

2018-07-01

The turbine based combined cycle engine has become the most promising hypersonic airbreathing propulsion system for its superiority of ground self-starting, wide flight envelop and reusability. The simulation model of the turbine based combined cycle engine plays an important role in the research of performance analysis and control system design. In this paper, a turbine based combined cycle engine mathematical model is built on the Simulink platform, including a dual-channel air intake system, a turbojet engine and a ramjet. It should be noted that the model of the air intake system is built based on computational fluid dynamics calculation, which provides valuable raw data for modeling of the turbine based combined cycle engine. The aerodynamic characteristics of turbine based combined cycle engine in turbojet mode, ramjet mode and mode transition process are studied by the mathematical model, and the influence of dominant variables on performance and safety of the turbine based combined cycle engine is analyzed. According to the stability requirement of thrust output and the safety in the working process of turbine based combined cycle engine, a control law is proposed that could guarantee the steady output of thrust by controlling the control variables of the turbine based combined cycle engine in the whole working process.

40 CFR 1065.125 - Engine intake air.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Engine intake air. 1065.125 Section 1065.125 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.125 Engine intake air. (a) Use the intake-air...

40 CFR 1065.125 - Engine intake air.

Code of Federal Regulations, 2010 CFR

2010-07-01

... engines with multiple intakes with separate humidity measurements at each intake, use a flow-weighted average humidity for NOX corrections. If individual flows of each intake are not measured, use good engineering judgment to estimate a flow-weighted average humidity. (3) Temperature. Good engineering judgment...

30 CFR 250.610 - Diesel engine air intakes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Diesel engine air intakes. 250.610 Section 250... Well-Workover Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway...

40 CFR 89.325 - Engine intake air temperature measurement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 89.325 Section 89.325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air...

Engine with pulse-suppressed dedicated exhaust gas recirculation

DOEpatents

Keating, Edward J.; Baker, Rodney E.

2016-06-07

An engine assembly includes an intake assembly, a spark-ignited internal combustion engine, and an exhaust assembly. The intake assembly includes a charge air cooler disposed between an exhaust gas recirculation (EGR) mixer and a backpressure valve. The charge air cooler has both an inlet and an outlet, and the back pressure valve is configured to maintain a minimum pressure difference between the inlet of the charge air cooler and an outlet of the backpressure valve. A dedicated exhaust gas recirculation system is provided in fluid communication with at least one cylinder and with the EGR mixer. The dedicated exhaust gas recirculation system is configured to route all of the exhaust gas from the at least one cylinder to the EGR mixer for recirculation back to the engine.

30 CFR 250.610 - Diesel engine air intakes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Diesel engine air intakes. 250.610 Section 250.610 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR... Operations § 250.610 Diesel engine air intakes. No later than May 31, 1989, diesel engine air intakes shall...

30 CFR 250.510 - Diesel engine air intakes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Diesel engine air intakes. 250.510 Section 250.510 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT, REGULATION, AND ENFORCEMENT, DEPARTMENT OF... Well-Completion Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be...

30 CFR 250.510 - Diesel engine air intakes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Diesel engine air intakes. 250.510 Section 250.510 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to...

30 CFR 250.510 - Diesel engine air intakes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Diesel engine air intakes. 250.510 Section 250.510 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to...

30 CFR 250.510 - Diesel engine air intakes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Diesel engine air intakes. 250.510 Section 250.510 Mineral Resources BUREAU OF SAFETY AND ENVIRONMENTAL ENFORCEMENT, DEPARTMENT OF THE INTERIOR... Operations § 250.510 Diesel engine air intakes. Diesel engine air intakes must be equipped with a device to...

40 CFR 91.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... measurement. 91.309 Section 91.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 100 cm of the air-intake of the engine. The measurement location must be either in...

40 CFR 90.310 - Engine intake air humidity measurement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a) Humidity...

14 CFR 27.1121 - General.

Code of Federal Regulations, 2013 CFR

2013-01-01

... prevent local hot spots; (c) Exhaust gases must discharge clear of the engine air intake, fuel system... after the failure of an attempted engine start; (g) Each exhaust heat exchanger must incorporate means...

14 CFR 27.1121 - General.

Code of Federal Regulations, 2012 CFR

2012-01-01

... prevent local hot spots; (c) Exhaust gases must discharge clear of the engine air intake, fuel system... after the failure of an attempted engine start; (g) Each exhaust heat exchanger must incorporate means...

14 CFR 27.1121 - General.

Code of Federal Regulations, 2014 CFR

2014-01-01

... prevent local hot spots; (c) Exhaust gases must discharge clear of the engine air intake, fuel system... after the failure of an attempted engine start; (g) Each exhaust heat exchanger must incorporate means...

14 CFR 27.1121 - General.

Code of Federal Regulations, 2010 CFR

2010-01-01

... prevent local hot spots; (c) Exhaust gases must discharge clear of the engine air intake, fuel system... after the failure of an attempted engine start; (g) Each exhaust heat exchanger must incorporate means...

14 CFR 27.1121 - General.

Code of Federal Regulations, 2011 CFR

2011-01-01

... prevent local hot spots; (c) Exhaust gases must discharge clear of the engine air intake, fuel system... after the failure of an attempted engine start; (g) Each exhaust heat exchanger must incorporate means...

30 CFR 250.610 - Diesel engine air intakes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.610 Section 250.610 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND... engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device...

30 CFR 250.510 - Diesel engine air intakes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.510 Section 250.510 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND... engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel...

Decreasing carbon monoxide in the diving air of artisanal fishermen in the Yucatán peninsula by separation of engine exhaust from compressor intake.

PubMed

Chin, Walter; Huchim-Lara, Oswaldo; Salas, Silvia

2016-01-01

Artisanal fishermen in the Yucatán Peninsula utilize hookah dive systems (HDS). The air compressors in these HDS are not filtered, and the intake is near the engine exhaust. This proximity allows carbon monoxide (CO) from the exhaust to directly enter the HDS volume tank and contaminate the fishermen diver's air supply. Conservative safety standards permit a diver's air supply to contain 10 parts per million (ppm) of CO. This study quantified the levels of CO in the diver's air supply both before and after physical separation of the engine exhaust from the compressor intake. CO levels in seven volume tanks were analyzed before and after a 1-inch hose was attached to the compressor intake and elevated 5 feet above the engine exhaust. The tanks were drained and refilled before collecting each set of pre- and post-intervention gas samples. Four CO measurements were collected before and after the intervention from each volume tank. A C-Squared© CO Analyzer (± 1 ppm), calibrated with a Praxair 70 ppm CON2 gas (± 5%), was used to analyze the gas samples. A paired samples t-test shows a statistically significant difference in average CO values before and after the intervention (t = 6.8674, df: 27; p⟨0.0001). The physical separation of the engine exhaust from the compressor intake reduced the CO contamination of the diver air supply by 72%. This intervention could be applied to the hookah systems in the rest of the fishing cooperative to reduce the divers' risk of CO poisoning. Copyright© Undersea and Hyperbaric Medical Society.

Dedicated EGR engine with dynamic load control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hayman, Alan W.; McAlpine, Robert S.; Keating, Edward J.

An internal combustion engine comprises a first engine bank and a second engine bank. A first intake valve is disposed in an intake port of a cylinder of the first engine bank, and is configured for metering the first flow of combustion air by periodically opening and closing according to a first intake valve lift and duration characteristic. A variable valve train control mechanism is configured for affecting the first intake valve lift and duration characteristic. Either a lift or duration of the first intake valve is modulated so as to satisfy an EGR control criterion.

Modification and performance evaluation of a mono-valve engine

NASA Astrophysics Data System (ADS)

Behrens, Justin W.

A four-stroke engine utilizing one tappet valve for both the intake and exhaust gas exchange processes has been built and evaluated. The engine operates under its own power, but has a reduced power capacity than the conventional 2-valve engine. The reduction in power is traced to higher than expected amounts of exhaust gases flowing back into the intake system. Design changes to the cylinder head will fix the back flow problems, but the future capacity of mono-valve engine technology cannot be estimated. The back flow of exhaust gases increases the exhaust gas recirculation (EGR) rate and deteriorates combustion. Intake pressure data shows the mono-valve engine requires an advanced intake valve closing (IVC) time to prevent back flow of charge air. A single actuation camshaft with advanced IVC was tested in the mono-valve engine, and was found to improve exhaust scavenging at TDC and nearly eliminated all charge air back flow at IVC. The optimum IVC timing is shown to be approximately 30 crank angle degrees after BDC. The mono-valve cylinder head utilizes a rotary valve positioned above the tappet valve. The open spaces inside the rotary valveand between the rotary valve and tappet valve represent a common volume that needs to be reduced in order to reduce the base EGR rate. Multiple rotary valve configurations were tested, and the size of the common volume was found to have no effect on back flow but a direct effect on the EGR rate and engine performance. The position of the rotary valve with respect to crank angle has a direct effect on the scavenging process. Optimum scavenging occurs when the intake port is opened just after TDC.

Idle speed and fuel vapor recovery control system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orzel, D.V.

1993-06-01

A method for controlling idling speed of an engine via bypass throttle connected in parallel to a primary engine throttle and for controlling purge flow through a vapor recovery system into an air/fuel intake of the engine is described, comprising the steps of: positioning the bypass throttle to decrease any difference between a desired engine idle speed and actual engine idle speed; and decreasing the purge flow when said bypass throttle position is less than a preselected fraction of a maximum bypass throttle position.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Furuya, K.; Yago, T.

A system is disclosed for rapidly warming up a catalytic converter provided to an automotive internal combustion engine to purify the exhaust gas. The system includes a vacuum-operated device to increase the opening degree of the throttle valve by a predetermined degree to thereby increase the quantity of the exhaust gas and another vacuum-operated device to retard the ignition timing of the engine to a predetermined extent to thereby raise the temperature of the exhaust gas. The two devices are connected by a vacuum passage to the intake passage of the engine at a section downstream of the throttle valvemore » in series, and an electromagnetic valve renders the vacuum passage effective to thereby actuate the vacuum-operated devices only when the engine is idling under cold condition. Because of the series connection of the two devices, an intake vacuum is applied to the two devices in desirable sequence.« less

Preventive Maintenance. FMO: Fundamentals of Machine Operation. Third Edition.

ERIC Educational Resources Information Center

Hathaway, Louis

This text is intended to provide students with basic information on conducting preventive maintenance on agricultural machinery. The following topics are covered in the individual chapters: the importance of preventive maintenance and recommended service intervals; engine intake and exhaust systems (air cleaners, turbochargers, intake and exhaust…

40 CFR 91.310 - Engine intake air humidity measurement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply. Air...

14 CFR 23.1091 - Air induction system.

Code of Federal Regulations, 2010 CFR

2010-01-01

... and their accessories must supply the air required by that engine and auxiliary power unit and their... cowling if the emergence of backfire flames will result in a hazard. (3) The supplying of air to the engine through the alternate air intake system may not result in a loss of excessive power in addition to...

Submarine Construction (Unterseebootsbau)

DTIC Science & Technology

1972-08-01

PIPE FOR THE SNORKEL EXHAUST MAST 11 AIR EXIT (GENERALLY TO MAIN AIR INDUCTION LINE) 12 EXHAUST GAS INLET FROM EXHAUST GAS LINE SIDE VIEW (MAST...Electric Engine 76 Diesel Engines 79 Air Intake and Gas Exhaust Systems for the Diesel Engines 79 Diesel Fuel and Pressurized Water System 82...Lines of a Submarine ■. 31 Figure 6 - Lines of a Submersible 31 Figure 7 - Twin- Screw Stern Configurations 34 Figure 8 - Single- Screw Stern

Controlling exhaust gas recirculation

DOEpatents

Zurlo, James Richard [Madison, WI; Konkle, Kevin Paul [West Bend, WI; May, Andrew [Milwaukee, WI

2012-01-31

In controlling an engine, an amount of an intake charge provided, during operation of the engine, to a combustion chamber of the engine is determined. The intake charge includes an air component, a fuel component and a diluent component. An amount of the air component of the intake charge is determined. An amount of the diluent component of the intake charge is determined utilizing the amount of the intake charge, the amount of the air component and, in some instances, the amount of the fuel component. An amount of a diluent supplied to the intake charge is adjusted based at least in part on the determined amount of diluent component of the intake charge.

Investigation of the Behavior of Fuel in the Intake Manifold and its Relation to S. I. Engines, 1980-1983

NASA Astrophysics Data System (ADS)

Servati, Hamid Beyragh

A liquid fuel film formation on the walls of an intake manifold adversely affects the engine performance and alters the overall air/fuel ratio from that scheduled by a fuel injector or carburetor and leads to adverse effects in vehicle driveability, exhaust emissions, and fuel economy. In this dissertation, the intake manifold is simulated by a horizontal circular duct. A model is provided to predict the rate of deposition and evaporation of the droplets in the intake manifold. The liquid fuel flow rate into the cylinders, mean film velocity and film thickness are determined as functions of engine parameters for both steady and transient operating conditions of the engine. A mathematical engine model is presented to simulate the dynamic interactions of the various engine components such as the air/fuel inlet element, intake manifold, combustion, dynamics and exhaust emissions. Inputs of the engine model are the intake manifold pressure and temperature, throttle angle, and air/fuel ratio. The observed parameters are the histories of fuel film thickness and velocity, fuel consumption, engine speed, engine speed hesitation time, and histories of CO, CO(,2), NO(,x), CH(,n), and O(,2). The effects of different air/fuel ratio control strategies on engine performance and observed parameters are also shown.

40 CFR 1065.101 - Overview.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Overview. 1065.101 Section 1065.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING... equipment includes three broad categories-dynamometers, engine fluid systems (such as fuel and intake-air...

40 CFR 1065.101 - Overview.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Overview. 1065.101 Section 1065.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING... equipment includes three broad categories-dynamometers, engine fluid systems (such as fuel and intake-air...

40 CFR 1065.101 - Overview.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Overview. 1065.101 Section 1065.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING... equipment includes three broad categories-dynamometers, engine fluid systems (such as fuel and intake-air...

40 CFR 1065.101 - Overview.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Overview. 1065.101 Section 1065.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING... equipment includes three broad categories-dynamometers, engine fluid systems (such as fuel and intake-air...

40 CFR 1065.101 - Overview.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Overview. 1065.101 Section 1065.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING... equipment includes three broad categories-dynamometers, engine fluid systems (such as fuel and intake-air...

40 CFR 90.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C. ...

40 CFR 90.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C. ...

40 CFR 90.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C. ...

40 CFR 90.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air temperature... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...) The temperature measurements must be accurate to within ±2 °C. ...

Design Definition Study Report. Full Crew Interaction Simulator-Laboratory Model (FCIS-LM) (Device X17B7). Volume I. Problem Analysis.

DTIC Science & Technology

1978-06-01

and Sound Levels. Tank sound characteris- tics can be categorized by four areas of tank operation. These are: engine starting and running, mobility or...the use of the ballistic computer system. The indirect sighting and fire control system consists of the elevation quadrant M13A3, a control light source...in low ambient 2-22 temperatures. No controls or indicators are provided for the engine air intake system. The exhaust system has four engine

40 CFR 90.309 - Engine intake air temperature measurement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 90.309 Section 90.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...

Increasing the volumetric efficiency of Diesel engines by intake pipes

NASA Technical Reports Server (NTRS)

List, Hans

1933-01-01

Development of a method for calculating the volumetric efficiency of piston engines with intake pipes. Application of this method to the scavenging pumps of two-stroke-cycle engines with crankcase scavenging and to four-stroke-cycle engines. The utility of the method is demonstrated by volumetric-efficiency tests of the two-stroke-cycle engines with crankcase scavenging. Its practical application to the calculation of intake pipes is illustrated by example.

Assessing the Challenges Associated with Developing an Integrated Modeling Approach for Predicting and Managing Water Quality and Quantity from the Watershed through the Drinking Water Treatment System

EPA Science Inventory

Natural and Engineered water systems interact throughout watersheds (e.g., at water intakes, wastewater outfalls and water pipe breaks of all kinds), and while there is clearly a link between watershed activities and the quality of water entering the engineered environment, surfa...

Rotary engine cooling system

NASA Technical Reports Server (NTRS)

Jones, Charles (Inventor); Gigon, Richard M. (Inventor); Blum, Edward J. (Inventor)

1985-01-01

A rotary engine has a substantially trochoidal-shaped housing cavity in which a rotor planetates. A cooling system for the engine directs coolant along a single series path consisting of series connected groups of passages. Coolant enters near the intake port, passes downwardly and axially through the cooler regions of the engine, then passes upwardly and axially through the hotter regions. By first flowing through the coolest regions, coolant pressure is reduced, thus reducing the saturation temperature of the coolant and thereby enhancing the nucleate boiling heat transfer mechanism which predominates in the high heat flux region of the engine during high power level operation.

Integration of air separation membrane and coalescing filter for use on an inlet air system of an engine

DOEpatents

Moncelle, Michael E.

2003-01-01

An intake air separation system suitable for combustion air of an internal combustion engine. An air separation device of the system includes a plurality of fibers, each fiber having a tube with a permeation barrier layer on the outer surface thereof and a coalescing layer on the inner surface thereof, to restrict fluid droplets from contacting the permeation barrier layer.

Intake port

DOEpatents

Mendler, Edward Charles

2005-02-01

The volumetric efficiency and power of internal combustion engines is improved with an intake port having an intake nozzle, a venturi, and a surge chamber. The venturi is located almost halfway upstream the intake port between the intake valves and the intake plenum enabling the venturi throat diameter to be exceptionally small for providing an exceptionally high ram velocity and an exceptionally long and in turn high efficiency diffuser flowing into the surge chamber. The intake port includes an exceptionally large surge chamber volume for blow down of the intake air into the working cylinder of the engine.

40 CFR 91.416 - Intake air flow measurement specifications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Intake air flow measurement... Procedures § 91.416 Intake air flow measurement specifications. (a) If used, the engine intake air flow measurement method used must have a range large enough to accurately measure the air flow over the engine...

Active Aircraft Pylon Noise Control System

NASA Technical Reports Server (NTRS)

Thomas, Russell H. (Inventor); Czech, Michael J (Inventor); Elmiligui, Alaa A. (Inventor)

2015-01-01

An active pylon noise control system for an aircraft includes a pylon structure connecting an engine system with an airframe surface of the aircraft and having at least one aperture to supply a gas or fluid therethrough, an intake portion attached to the pylon structure to intake a gas or fluid, a regulator connected with the intake portion via a plurality of pipes, to regulate a pressure of the gas or fluid, a plenum chamber formed within the pylon structure and connected with the regulator, and configured to receive the gas or fluid as regulated by the regulator, and a plurality of injectors in communication with the plenum chamber to actively inject the gas or fluid through the plurality of apertures of the pylon structure.

Active Aircraft Pylon Noise Control System

NASA Technical Reports Server (NTRS)

Thomas, Russell H. (Inventor); Czech, Michael J. (Inventor); Elmiligui, Alaa A. (Inventor)

2017-01-01

An active pylon noise control system for an aircraft includes a pylon structure connecting an engine system with an airframe surface of the aircraft and having at least one aperture to supply a gas or fluid therethrough, an intake portion attached to the pylon structure to intake a gas or fluid, a regulator connected with the intake portion via a plurality of pipes, to regulate a pressure of the gas or fluid, a plenum chamber formed within the pylon structure and connected with the regulator, and configured to receive the gas or fluid as regulated by the regulator, and a plurality of injectors in communication with the plenum chamber to actively inject the gas or fluid through the plurality of apertures of the pylon structure.

Design and development of the Waukesha Custom Engine Control Air/Fuel Module

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moss, D.W.

1996-12-31

The Waukesha Custom Engine Control Air/Fuel Module (AFM) is designed to control the air-fuel ratio for all Waukesha carbureted, gaseous fueled, industrial engine. The AFM is programmed with a personal computer to run in one of four control modes: catalyst, best power, best economy, or lean-burn. One system can control naturally aspirated, turbocharged, in-line or vee engines. The basic system consists of an oxygen sensing system, intake manifold pressure transducer, electronic control module, actuator and exhaust thermocouple. The system permits correct operation of Waukesha engines in spite of changes in fuel pressure or temperature, engine load or speed, and fuelmore » composition. The system utilizes closed loop control and is centered about oxygen sensing technology. An innovative approach to applying oxygen sensors to industrial engines provides very good performance, greatly prolongs sensor life, and maintains sensor accuracy. Design considerations and operating results are given for application of the system to stationary, industrial engines operating on fuel gases of greatly varying composition.« less

A Method for Turbocharging Four-Stroke Single Cylinder Engines

NASA Astrophysics Data System (ADS)

Buchman, Michael; Winter, Amos

2014-11-01

Turbocharging is not conventionally used with single cylinder engines due to the timing mismatch between when the turbo is powered and when it can deliver air to the cylinder. The proposed solution involves a fixed, pressurized volume - which we call an air capacitor - on the intake side of the engine between the turbocharger and intake valves. The capacitor acts as a buffer and would be implemented as a new style of intake manifold with a larger volume than traditional systems. This talk will present the flow analysis used to determine the optimal size for the capacitor, which was found to be four to five times the engine capacity, as well as its anticipated contributions to engine performance. For a capacitor sized for a one-liter engine, the time to reach operating pressure was found to be approximately two seconds, which would be acceptable for slowly accelerating applications and steady state applications. The air density increase that could be achieved, compared to ambient air, was found to vary between fifty percent for adiabatic compression and no heat transfer from the capacitor, to eighty percent for perfect heat transfer. These increases in density are proportional to, to first order, the anticipated power increases that could be realized. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1122374.

Engine Air Intake Manifold Having Built In Intercooler

DOEpatents

Freese, V, Charles E.

2000-09-12

A turbocharged V type engine can be equipped with an exhaust gas recirculation cooler integrated into the intake manifold, so as to achieve efficiency, cost reductions and space economization improvements. The cooler can take the form of a tube-shell heat exchanger that utilizes a cylindrical chamber in the air intake manifold as the heat exchanger housing. The intake manifold depends into the central space formed by the two banks of cylinders on the V type engine, such that the central space is effectively utilized for containing the manifold and cooler.

Design and development of a probe-based multiplexed multi-species absorption spectroscopy sensor for characterizing transient gas-parameter distributions in the intake systems of I.C. engines

DOE PAGES

Jatana, Gurneesh; Geckler, Sam; Koeberlein, David; ...

2016-09-01

We designed and developed a 4-probe multiplexed multi-species absorption spectroscopy sensor system for gas property measurements on the intake side of commercial multi-cylinder internal-combustion (I.C.) engines; the resulting cycle- and cylinder-resolved concentration, temperature and pressure measurements are applicable for assessing spatial and temporal variations in the recirculated exhaust gas (EGR) distribution at various locations along the intake gas path, which in turn is relevant to assessing cylinder charge uniformity, control strategies, and CFD models. Furthermore, the diagnostic is based on absorption spectroscopy and includes an H 2O absorption system (utilizing a 1.39 m distributed feedback (DFB) diode laser) for measuringmore » gas temperature, pressure, and H 2O concentration, and a CO 2 absorption system (utilizing a 2.7 m DFB laser) for measuring CO 2 concentration. The various lasers, optical components and detectors were housed in an instrument box, and the 1.39- m and 2.7- m lasers were guided to and from the engine-mounted probes via optical fibers and hollow waveguides, respectively. The 5kHz measurement bandwidth allows for near-crank angle resolved measurements, with a resolution of 1.2 crank angle degrees at 1000 RPM. Our use of compact stainless steel measurement probes enables simultaneous multi-point measurements at various locations on the engine with minimal changes to the base engine hardware; in addition to resolving large-scale spatial variations via simultaneous multi-probe measurements, local spatial gradients can be resolved by translating individual probes. Along with details of various sensor design features and performance, we also demonstrate validation of the spectral parameters of the associated CO 2 absorption transitions using both a multi-pass heated cell and the sensor probes.« less

77 FR 67263 - Airworthiness Directives; Airbus Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-09

... flight cycles. US Airways stated that the engine inlet cowl inspection should follow Airbus Mandatory... months after the engine air intake cowl has accumulated 5,000 total flight cycles. (2) For any engine air... the same airplane has accumulated 5,000 flight cycles or less since the engine air intake cowl was...

High efficiency stoichiometric internal combustion engine system

DOEpatents

Winsor, Richard Edward; Chase, Scott Allen

2009-06-02

A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

5. Wayne Chandler, Photographer, May 2000 Photographic copy of engineering ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Wayne Chandler, Photographer, May 2000 Photographic copy of engineering drawings, dated 1912, by U.S. Army Corps of Engineers. Drawing in possession of U.S. Army Corps of Engineers, Sault Ste. Marie, Michigan. General plan of wide walls showing location of filling and emptying culvert intakes and discharges, as well as cable system for operating gates. - St. Mary's Falls Canal, Soo Locks, Davis Lock Subcomplex, Davis Lock, St. Mary's River at Falls, Sault Ste. Marie, Chippewa County, MI

40 CFR 1054.501 - How do I run a valid emission test?

Code of Federal Regulations, 2014 CFR

2014-07-01

... accumulation, use the test fuel or any commercially available fuel that is representative of the fuel that in-use engines will use. Note that § 1054.145(n) allows for testing with gasoline test fuels specified by... fuel system representing a production configuration that sends fuel vapors to the test engine's intake...

Exhaust Composition in a Small Internal Combustion Engine Using FTIR Spectroscopy

DTIC Science & Technology

2015-06-18

ects of broadband sooting on IRF transmittance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 xi...IndiSmart combustion analyzer. This system conducted data acquisition on various high speed sensors including in- cylinder pressure, intake pressure...Crankshaft position was measured once per revolution by a hall-e↵ect sensor connected to the ignition 56 control unit. The engines were air cooled with

ARC Researchers at 2016 SAE Congress

Science.gov Websites

PFL580; Room 413 B Engine Block, Cylinder Heads, Oil & Water Pumps, Intake & Exhaust Systems This Systems (CRS) and other related areas. These papers could include several of the following: technology Life Estimation of Linear Vibratory Systems Vasiliki TSIANIKA; Monica T. Majcher; Zissimos Mourelatos

The two-stroke poppet valve engine. Part 1: Intake and exhaust ports flow experimental assessments

NASA Astrophysics Data System (ADS)

Kamili Zahidi, M.; Razali Hanipah, M.; Ramasamy, D.; Noor, M. M.; Kadirgama, K.; Rahman, M. M.

2017-10-01

A two-stroke poppet valve engine is developed to overcome the common problems in conventional two-stroke engine designs. However, replacing piston control port with poppet valve will resulted different flow behaviour. This paper is looking at experimental assessment on a two-stroke poppet valve engine configuration to investigate the port flow performance. The aims are to evaluate the intake and exhaust coefficient of discharge and assess the twostroke capability of the cylinder head. The results has shown comparable coefficient of discharge values as production engine for the intake while the exhaust has higher values which is favourable for the two-stroke cycle operation.

Design and Control of a Proof-of-Concept Active Jet Engine Intake Using Shape Memory Alloy Actuators

NASA Technical Reports Server (NTRS)

Song, Gangbing; Ma, Ning; Penney, Nicholas; Barr, Todd; Lee, Ho-Jun; Arnold, Steven M.

2004-01-01

The design and control of a novel proof-of-concept active jet engine intake using Nickel-Titanium (Ni-Ti or Nitinol) shape memory alloy (SMA) wire actuators is used to demonstrate the potential of an adaptive intake to improve the fuel efficiency of a jet engine. The Nitinol SMA material is selected for this research due to the material's ability to generate large strains of up to 5 percent for repeated operations, a high power-to-weight ratio, electrical resistive actuation, and easy fabrication into a variety of shapes. The proof-of-concept engine intake employs an overlapping leaf design arranged in a concentric configuration. Each leaf is mounted on a supporting bar that rotates upon actuation by SMA wires electrical resistive heating. Feedback control is enabled through the use of a laser range sensor to detect the movement of a leaf and determine the radius of the intake area. Due to the hysteresis behavior inherent in SMAs, a nonlinear robust controller is used to direct the SMA wire actuation. The controller design utilizes the sliding-mode approach to compensate for the nonlinearities associated with the SMA actuator. Feedback control experiments conducted on a fabricated proof-of-concept model have demonstrated the capability to precisely control the intake area and achieve up to a 25 percent reduction in intake area. The experiments demonstrate the feasibility of engine intake area control using the proposed design.

Diesel emission reduction using internal exhaust gas recirculation

DOEpatents

He, Xin [Denver, CO; Durrett, Russell P [Bloomfield Hills, MI

2012-01-24

A method for controlling combustion in a direct-injection diesel engine includes monitoring a crankshaft rotational position of a cylinder of the engine, monitoring an engine load, determining an intake stroke within the cylinder based upon the crankshaft rotational position, and when the engine load is less than a threshold engine load, opening an exhaust valve for the cylinder during a portion of the intake stroke.

Use of exhaust gas as sweep flow to enhance air separation membrane performance

DOEpatents

Dutart, Charles H.; Choi, Cathy Y.

2003-01-01

An intake air separation system for an internal combustion engine is provided with purge gas or sweep flow on the permeate side of separation membranes in the air separation device. Exhaust gas from the engine is used as a purge gas flow, to increase oxygen flux in the separation device without increasing the nitrogen flux.

Diesel Combustion and Emission Using High Boost and High Injection Pressure in a Single Cylinder Engine

NASA Astrophysics Data System (ADS)

Aoyagi, Yuzo; Kunishima, Eiji; Asaumi, Yasuo; Aihara, Yoshiaki; Odaka, Matsuo; Goto, Yuichi

Heavy-duty diesel engines have adopted numerous technologies for clean emissions and low fuel consumption. Some are direct fuel injection combined with high injection pressure and adequate in-cylinder air motion, turbo-intercooler systems, and strong steel pistons. Using these technologies, diesel engines have achieved an extremely low CO2 emission as a prime mover. However, heavy-duty diesel engines with even lower NOx and PM emission levels are anticipated. This study achieved high-boost and lean diesel combustion using a single cylinder engine that provides good engine performance and clean exhaust emission. The experiment was done under conditions of intake air quantity up to five times that of a naturally aspirated (NA) engine and 200MPa injection pressure. The adopted pressure booster is an external supercharger that can control intake air temperature. In this engine, the maximum cylinder pressure was increased and new technologies were adopted, including a monotherm piston for endurance of Pmax =30MPa. Moreover, every engine part is newly designed. As the boost pressure increases, the rate of heat release resembles the injection rate and becomes sharper. The combustion and brake thermal efficiency are improved. This high boost and lean diesel combustion creates little smoke; ISCO and ISTHC without the ISNOx increase. It also yields good thermal efficiency.

Experimental Evaluation of a Method for Turbocharging Four-Stroke, Single Cylinder, Internal Combustion Engines

NASA Astrophysics Data System (ADS)

Buchman, Michael; Winter, Amos

2015-11-01

Turbocharging an engine increases specific power, improves fuel economy, reduces emissions, and lowers cost compared to a naturally aspirated engine of the same power output. These advantages make turbocharging commonplace for multi-cylinder engines. Single cylinder engineers are not commonly turbocharged due to the phase lag between the exhaust stroke, which powers the turbocharger, and the intake stroke, when air is pumped into the engine. Our proposed method of turbocharging single cylinder engines is to add an ``air capacitor'' to the intake manifold, an additional volume that acts as a buffer to store compressed air between the exhaust and intake strokes, and smooth out the pressure pulses from the turbocharger. This talk presents experimental results from a single cylinder, turbocharged diesel engine fit with various sized air capacitors. Power output from the engine was measured using a dynamometer made from a generator, with the electrical power dissipated with resistive heating elements. We found that intake air density increases with capacitor size as theoretically predicted, ranging from 40 to 60 percent depending on heat transfer. Our experiment was able to produce 29 percent more power compared to using natural aspiration. These results validated that an air capacitor and turbocharger may be a simple, cost effective means of increasing the power density of single cylinder engines.

Hybrid Automotive Engine Using Ethanol-Burning Miller Cycle

NASA Technical Reports Server (NTRS)

Weinstein, Leonard

2004-01-01

A proposed hybrid (internal-combustion/ electric) automotive engine system would include as its internal-combustion subsystem, a modified Miller-cycle engine with regenerative air preheating and with autoignition like that of a Diesel engine. The fuel would be ethanol and would be burned lean to ensure complete combustion. Although the proposed engine would have a relatively low power-to-weight ratio compared to most present engines, this would not be the problem encountered if this engine were used in a non-hybrid system since hybrid systems require significantly lower power and thus smaller engines than purely internal-combustion-engine-driven vehicles. The disadvantage would be offset by the advantages of high fuel efficiency, low emission of nitrogen oxides and particulate pollutants, and the fact that ethanol is a renewable fuel. The original Miller-cycle engine, named after its inventor, was patented in the 1940s and is the basis of engines used in some modern automobiles, but is not widely known. In somewhat oversimplified terms, the main difference between a Miller-cycle engine and a common (Otto-cycle) automobile engine is that the Miller-cycle engine has a longer expansion stroke while retaining the shorter compression stroke. This is accomplished by leaving the intake valve open for part of the compression stroke, whereas in the Otto cycle engine, the intake valve is kept closed during the entire compression stroke. This greater expansion ratio makes it possible to extract more energy from the combustion process without expending more energy for compression. The net result is greater efficiency. In the proposed engine, the regenerative preheating would be effected by running the intake air through a heat exchanger connected to the engine block. The regenerative preheating would offer two advantages: It would ensure reliable autoignition during operation at low ambient temperature and would help to cool the engine, thereby reducing the remainder of the power needed for cooling and thereby further contributing to efficiency. An electrical resistance air preheater might be needed to ensure autoignition at startup and during a short warmup period. Because of the autoignition, the engine could operate without either spark plugs or glow plugs. Ethanol burns relatively cleanly and has been used as a motor fuel since the invention of internal-combustion engines. However, the energy content of ethanol per unit weight of ethanol is less than that of Diesel fuel or gasoline, and ethanol has a higher heat of vaporization. Because the Miller cycle offers an efficiency close to that of the Diesel cycle, burning ethanol in a Miller-cycle engine gives about as much usable output energy per unit volume of fuel as does burning gasoline in a conventional gasoline automotive engine. Because of the combination of preheating, running lean, and the use of ethyl alcohol, the proposed engine would generate less power per unit volume than does a conventional automotive gasoline engine. Consequently, for a given power level, the main body of the proposed engine would be bulkier. However, because little or no exhaust cleanup would be needed, the increase in bulk of the engine could be partially offset by the decrease in bulk of the exhaust system. The regenerative preheating also greatly reduces the external engine cooling requirement, and would translate to reduced engine bulk. It may even be possible to accomplish the remaining cooling of the engine by use of air only, eliminating the bulk and power consumption of a water cooling system. The combination of a Miller-cycle engine with regenerative air preheating, ethyl alcohol fuel, and hybrid operation could result in an automotive engine system that satisfies the need for a low pollution, high efficiency, and simple engine with a totally renewable fuel.

77 FR 37344 - Airworthiness Directives; Airbus Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-21

... reports of extensive damage to engine air intake cowls as a result of acoustic panel collapse. This proposed AD would require repetitive inspections of the three inner acoustic panels of both engine air... finding extensive damage to engine air intake cowls as a result of acoustic panel collapse, most probably...

Engine restart aid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fedewa, Andrew

A system is disclosed comprising an engine having coolant passages defined therethrough, a first coolant pump, and a first radiator. The system additionally comprises a second coolant pump, a second radiator, and a liquid-to-air heat exchanger configured to condition the temperature of intake air to the engine. The system further includes a coolant valve means. For a first configuration of the coolant valve means the first coolant pump is configured to urge coolant through the coolant passages in the engine and through the first radiator, and the second coolant pump is configured to urge coolant through the liquid-to-air heat exchangermore » and through the second radiator. For a second configuration of the coolant valve means the second coolant pump is configured to urge coolant through the coolant passages in the engine and through the liquid-to-air heat exchanger. A method for controlling the system is also disclosed.« less

40 CFR 204.55-3 - Configuration identification.

Code of Federal Regulations, 2011 CFR

2011-07-01

... compressor stages. (3) Maximum pressure (psi). (4) Air intake system of compressor: (i) Number of filters; (ii) Type of filters. (5) The engine system: (i) Number of cylinders and configuration (L-6, V-8, V-12..., water cooled. (7) Fan: (i) Diameter; (ii) Maximum fan rpm. (8) The compressor enclosure: (i) Height...

40 CFR 204.55-3 - Configuration identification.

Code of Federal Regulations, 2013 CFR

2013-07-01

... compressor stages. (3) Maximum pressure (psi). (4) Air intake system of compressor: (i) Number of filters; (ii) Type of filters. (5) The engine system: (i) Number of cylinders and configuration (L-6, V-8, V-12..., water cooled. (7) Fan: (i) Diameter; (ii) Maximum fan rpm. (8) The compressor enclosure: (i) Height...

40 CFR 204.55-3 - Configuration identification.

Code of Federal Regulations, 2014 CFR

2014-07-01

... compressor stages. (3) Maximum pressure (psi). (4) Air intake system of compressor: (i) Number of filters; (ii) Type of filters. (5) The engine system: (i) Number of cylinders and configuration (L-6, V-8, V-12..., water cooled. (7) Fan: (i) Diameter; (ii) Maximum fan rpm. (8) The compressor enclosure: (i) Height...

40 CFR 204.55-3 - Configuration identification.

Code of Federal Regulations, 2012 CFR

2012-07-01

... compressor stages. (3) Maximum pressure (psi). (4) Air intake system of compressor: (i) Number of filters; (ii) Type of filters. (5) The engine system: (i) Number of cylinders and configuration (L-6, V-8, V-12..., water cooled. (7) Fan: (i) Diameter; (ii) Maximum fan rpm. (8) The compressor enclosure: (i) Height...

Tuned intake air system for a rotary engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corbett, W.D.

This patent describes a rotary internal combustion engine for an outboard board motor. It comprises a plenum chamber attached to the rear of the engine; and the plenum chamber including an inner wall attached to the exhaust manifold; an inlet conduit connecting the cooling air exit passage and the inlet air opening; an outlet conduit connecting the outlet air opening and the combustion air inlet; and the outlet conduit terminating in a combustion air outlet in the inner wall of the plenum chamber.

Mazda's new V-6 gasoline engine and its innovative induction system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hatamura, K.; Morishita, K.; Asanomi, K.

1987-01-01

Mazda succeeded in the development of a new V-type 6-cylinder engine series comprising 2-liter JF naturally aspirated and turbocharged units and also a 3-liter JE naturally aspirated unit. This engine is 60-degree-banked and has 18 valves: two intake valves and one exhaust valve per cylinder. Various techniques, such as High Rigidity Cylinder Block and HLA, are adopted to upgrade quietness and smoothness. The Dynamic Charge Effects system, a combination of inertia and resonance charge effects, is modeled on the principle of two-degree-of-freedom system. The application of this principle helped develop the Induction system that is compatible with the three enginemore » types. The turbocharger adopted on the JF engine is of a twin scroll type to considerably improve power response quality and increase torque at low speed. Triple Port Induction Control System is used to help improve fuel economy and running performance.« less

Numerical analysis of flow interaction of turbine system in two-stage turbocharger of internal combustion engine

NASA Astrophysics Data System (ADS)

Liu, Y. B.; Zhuge, W. L.; Zhang, Y. J.; Zhang, S. Y.

2016-05-01

To reach the goal of energy conservation and emission reduction, high intake pressure is needed to meet the demand of high power density and high EGR rate for internal combustion engine. Present power density of diesel engine has reached 90KW/L and intake pressure ratio needed is over 5. Two-stage turbocharging system is an effective way to realize high compression ratio. Because turbocharging system compression work derives from exhaust gas energy. Efficiency of exhaust gas energy influenced by design and matching of turbine system is important to performance of high supercharging engine. Conventional turbine system is assembled by single-stage turbocharger turbines and turbine matching is based on turbine MAP measured on test rig. Flow between turbine system is assumed uniform and value of outlet physical quantities of turbine are regarded as the same as ambient value. However, there are three-dimension flow field distortion and outlet physical quantities value change which will influence performance of turbine system as were demonstrated by some studies. For engine equipped with two-stage turbocharging system, optimization of turbine system design will increase efficiency of exhaust gas energy and thereby increase engine power density. However flow interaction of turbine system will change flow in turbine and influence turbine performance. To recognize the interaction characteristics between high pressure turbine and low pressure turbine, flow in turbine system is modeled and simulated numerically. The calculation results suggested that static pressure field at inlet to low pressure turbine increases back pressure of high pressure turbine, however efficiency of high pressure turbine changes little; distorted velocity field at outlet to high pressure turbine results in swirl at inlet to low pressure turbine. Clockwise swirl results in large negative angle of attack at inlet to rotor which causes flow loss in turbine impeller passages and decreases turbine efficiency. However negative angle of attack decreases when inlet swirl is anti-clockwise and efficiency of low pressure turbine can be increased by 3% compared to inlet condition of clockwise swirl. Consequently flow simulation and analysis are able to aid in figuring out interaction mechanism of turbine system and optimizing turbine system design.

Highway Vehicle Retrofit Evaluation : Phase 2. Report. Testing and Final Evaluation Results.

DOT National Transportation Integrated Search

1976-11-01

This report presents the results of engine dynamometer and vehicle chassis dynamometer tests conducted with selected automotive retrofit devices in the classes of ultrasonic carburetors, high-velocity intake manifolds, tuned exhaust systems, and high...

Physiological significance of ghrelin revealed by studies using genetically engineered mouse models with modifications in the ghrelin system.

PubMed

Ariyasu, Hiroyuki; Akamizu, Takashi

2015-01-01

Ghrelin, an endogenous ligand for the growth hormone (GH) secretagogue receptor (GHS-R or ghrelin receptor), is a 28-amino acid acylated peptide mainly produced in the stomach. The pharmacological administration of ghrelin is known to exert diverse effects, such as stimulating GH secretion, promoting food intake, and increasing adiposity. In recent years, genetically engineered mouse models have provided important insights into the physiology of various hormones. In this review, we discuss current knowledge regarding the physiological significance of ghrelin on the basis of studies using genetically engineered mouse models with modifications in the ghrelin system.

An investigation of enhanced capability thermal barrier coating systems for diesel engine components

NASA Technical Reports Server (NTRS)

Holtzman, R. L.; Layne, J. L.; Schechter, B.

1984-01-01

Material systems and processes for the development of effective and durable thermal barriers for heavy duty diesel engines were investigated. Seven coating systems were evaluated for thermal conductivity, erosion resistance, corrosion/oxidation resistance, and thermal shock resistance. An advanced coating system based on plasma sprayed particle yttria stabilized zirconia (PS/HYSZ) was judged superior in these tests. The measured thermal conductivity of the selected coating was 0.893 W/m C at 371 C. The PS/HYSZ coating system was applied to the piston crown, fire deck and valves of a single cylinder low heat rejection diesel engine. The coated engine components were tested for 24 hr at power levels from 0.83 MPa to 1.17 MPa brake mean effective pressure. The component coatings survived the engine tests with a minimum of distress. The measured fire deck temperatures decreased 86 C (155 F) on the intake side and 42 C (75 F) on the exhaust side with the coating applied.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neitzel, D.A.; McKenzie, D.H.

To minimize adverse impact on aquatic ecosystems resulting from the operation of water intake structures, design engineers must have relevant information on the behavior, physiology and ecology of local fish and shellfish. Identification of stimulus/response relationships and the environmental factors that influence them is the first step in incorporating biological information in the design, location or modification of water intake structures. A procedure is presented in this document for providing biological input to engineers who are designing, locating or modifying a water intake structure. The authors discuss sources of stimuli at water intakes, historical approaches in assessing potential/actual impact andmore » review biological information needed for intake design.« less

Time Resolved Digital PIV Measurements of Flow Field Cyclic Variation in an Optical IC Engine

NASA Astrophysics Data System (ADS)

Jarvis, S.; Justham, T.; Clarke, A.; Garner, C. P.; Hargrave, G. K.; Halliwell, N. A.

2006-07-01

Time resolved digital particle image velocimetry (DPIV) experimental data is presented for the in-cylinder flow field development of a motored four stroke spark ignition (SI) optical internal combustion (IC) engine. A high speed DPIV system was employed to quantify the velocity field development during the intake and compression stroke at an engine speed of 1500 rpm. The results map the spatial and temporal development of the in-cylinder flow field structure allowing comparison between traditional ensemble average and cycle average flow field structures. Conclusions are drawn with respect to engine flow field cyclic variations.

System and method for diagnosing EGR performance using NOx sensor

DOEpatents

Mazur, Christopher John

2003-12-23

A method and system for diagnosing a condition of an EGR valve used in an engine system. The EGR valve controls the portion exhaust gases produced by such engine system and fed back to an intake of such engine system. The engine system includes a NOx sensor for measuring NOx in such exhaust. The method includes: determining a time rate of change in NOx measured by the NOx sensor; comparing the determined time rate of change in the measured NOx with a predetermined expected time rate of change in measured NOx; and determining the condition of the EGR valve as a function of such comparison. The method also includes: determining from NOx measured by the NOx sensor and engine operating conditions indications of instances when samples of such measured NOx are greater than an expected maximum NOx level for such engine condition and less than an expected minimum NOx level for such engine condition; and determining the condition of the EGR valve as a function of a statistical analysis of such indications. The method includes determining whether the NOx sensor is faulty and wherein the EGR condition determining includes determining whether the NOx sensor is faulty.

Gas flow calculation method of a ramjet engine

NASA Astrophysics Data System (ADS)

Kostyushin, Kirill; Kagenov, Anuar; Eremin, Ivan; Zhiltsov, Konstantin; Shuvarikov, Vladimir

2017-11-01

At the present study calculation methodology of gas dynamics equations in ramjet engine is presented. The algorithm is based on Godunov`s scheme. For realization of calculation algorithm, the system of data storage is offered, the system does not depend on mesh topology, and it allows using the computational meshes with arbitrary number of cell faces. The algorithm of building a block-structured grid is given. Calculation algorithm in the software package "FlashFlow" is implemented. Software package is verified on the calculations of simple configurations of air intakes and scramjet models.

Performance and emission characteristics of the thermal barrier coated SI engine by adding argon inert gas to intake mixture.

PubMed

Karthikeya Sharma, T

2015-11-01

Dilution of the intake air of the SI engine with the inert gases is one of the emission control techniques like exhaust gas recirculation, water injection into combustion chamber and cyclic variability, without scarifying power output and/or thermal efficiency (TE). This paper investigates the effects of using argon (Ar) gas to mitigate the spark ignition engine intake air to enhance the performance and cut down the emissions mainly nitrogen oxides. The input variables of this study include the compression ratio, stroke length, and engine speed and argon concentration. Output parameters like TE, volumetric efficiency, heat release rates, brake power, exhaust gas temperature and emissions of NOx, CO2 and CO were studied in a thermal barrier coated SI engine, under variable argon concentrations. Results of this study showed that the inclusion of Argon to the input air of the thermal barrier coated SI engine has significantly improved the emission characteristics and engine's performance within the range studied.

Development and Testing of a 6-Cylinder HCCI Engine for Distributed Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flowers, D L; Martinez-Frias, J; Espinosa-Loza, F

2005-07-12

This paper describes the technical approach for converting a Caterpillar 3406 natural gas spark ignited engine into HCCI mode. The paper describes all stages of the process, starting with a preliminary analysis that determined that the engine can be operated by preheating the intake air with a heat exchanger that recovers energy from the exhaust gases. This heat exchanger plays a dual role, since it is also used for starting the engine. For start-up, the heat exchanger is preheated with a natural gas burner. The engine is therefore started in HCCI mode, avoiding the need to handle the potentially difficultmore » transition from SI or diesel mode to HCCI. The fueling system was modified by replacing the natural gas carburetor with a liquid petroleum gas (LPG) carburetor. This modification sets an upper limit for the equivalence ratio at {phi} {approx} 0.4, which is ideal for HCCI operation and guarantees that the engine will not fail due to knock. Equivalence ratio can be reduced below 0.4 for low load operation with an electronic control valve. Intake boosting has been a challenge, as commercially available turbochargers are not a good match for the engine, due to the low HCCI exhaust temperature. Commercial introduction of HCCI engines for stationary power will therefore require the development of turbochargers designed specifically for this mode of operation. Considering that no appropriate off-the-shelf turbocharger for HCCI engines exists at this time, we are investigating mechanical supercharging options, which will deliver the required boost pressure (3 bar absolute intake) at the expense of some reduction in the output power and efficiency. An appropriate turbocharger can later be installed for improved performance when it becomes available or when a custom turbocharger is developed. The engine is now running in HCCI mode and producing power in an essentially naturally aspirated mode. Current work focuses on developing an automatic controller for obtaining consistent combustion in the 6 cylinders. The engine will then be tested for 1000 hours to demonstrate durability. This paper presents intermediate progress towards development of an HCCI engine for stationary power generation and next steps towards achieving the project goals.« less

Partial oxidation for improved cold starts in alcohol-fueled engines: Phase 2 topical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-04-01

Alcohol fuels exhibit poor cold-start performance because of their low volatility. Neat alcohol engines become difficult, if not impossible, to start at temperatures close to or below freezing. Improvements in the cold-start performance (both time to start and emissions) are essential to capture the full benefits of alcohols as an alternative transportation fuel. The objective of this project was to develop a neat alcohol partial oxidation (POX) reforming technology to improve an alcohol engine`s ability to start at low temperatures (as low as {minus}30 C) and to reduce its cold-start emissions. The project emphasis was on fuel-grade ethanol (E95) butmore » the technology can be easily extended to other alcohol fuels. Ultimately a compact, on-vehicle, ethanol POX reactor was developed as a fuel system component to produce a hydrogen-rich, fuel-gas mixture for cold starts. The POX reactor is an easily controllable combustion device that allows flexibility during engine startup even in the most extreme conditions. It is a small device that is mounted directly onto the engine intake manifold. The gaseous fuel products (or reformate) from the POX reactor exit the chamber and enter the intake manifold, either replacing or supplementing the standard ethanol fuel consumed during an engine start. The combustion of the reformate during startup can reduce engine start time and tail-pipe emissions.« less

Low emission turbo compound engine system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vuk,; Carl, T

2011-05-31

A diesel or HHCI engine has an air intake and an exhaust for products of combustion. A pair of turbochargers receive the products of combustion in a series relationship and an exhaust aftertreatment device receive the products of combustion from the downstream turbine. A power turbine receives the output from the exhaust aftertreatment device and an EGR system of the power turbine passes a selected portion of the output to a point upstream of the upstream turbocharger compressor. A device adds fuel to the aftertreatment device to regenerate the particulate filter and the power turbine recoups the additional energy. Themore » power turbine may be used to drive accessories or the prime output of the engine.« less

Internal combustion engine with rotary valve assembly having variable intake valve timing

DOEpatents

Hansen, Craig N.; Cross, Paul C.

1995-01-01

An internal combustion engine has rotary valves associated with movable shutters operable to vary the closing of intake air/fuel port sections to obtain peak volumetric efficiency over the entire range of speed of the engine. The shutters are moved automatically by a control mechanism that is responsive to the RPM of the engine. A foot-operated lever associated with the control mechanism is also used to move the shutters between their open and closed positions.

Airbreathing combined cycle engine systems

NASA Technical Reports Server (NTRS)

Rohde, John

1992-01-01

The Air Force and NASA share a common interest in developing advanced propulsion systems for commercial and military aerospace vehicles which require efficient acceleration and cruise operation in the Mach 4 to 6 flight regime. The principle engine of interest is the turboramjet; however, other combined cycles such as the turboscramjet, air turborocket, supercharged ejector ramjet, ejector ramjet, and air liquefaction based propulsion are also of interest. Over the past months careful planning and program implementation have resulted in a number of development efforts that will lead to a broad technology base for those combined cycle propulsion systems. Individual development programs are underway in thermal management, controls materials, endothermic hydrocarbon fuels, air intake systems, nozzle exhaust systems, gas turbines and ramjet ramburners.

Engine and method for operating an engine

DOEpatents

Lauper, Jr., John Christian; Willi, Martin Leo [Dunlap, IL; Thirunavukarasu, Balamurugesh [Peoria, IL; Gong, Weidong [Dunlap, IL

2008-12-23

A method of operating an engine is provided. The method may include supplying a combustible combination of reactants to a combustion chamber of the engine, which may include supplying a first hydrocarbon fuel, hydrogen fuel, and a second hydrocarbon fuel to the combustion chamber. Supplying the second hydrocarbon fuel to the combustion chamber may include at least one of supplying at least a portion of the second hydrocarbon fuel from an outlet port that discharges into an intake system of the engine and supplying at least a portion of the second hydrocarbon fuel from an outlet port that discharges into the combustion chamber. Additionally, the method may include combusting the combustible combination of reactants in the combustion chamber.

Working Characteristics of Variable Intake Valve in Compressed Air Engine

PubMed Central

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

Working characteristics of variable intake valve in compressed air engine.

PubMed

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

Effect of intake swirl on the performance of single cylinder direct injection diesel engine

NASA Astrophysics Data System (ADS)

Sharma, Vinod Kumar; Mohan, Man; Mouli, Chandra

2017-11-01

In the present work, the effect of inlet manifold geometry and swirl intensity on the direct injection (DI) diesel engine performance was investigated experimentally. Modifications in inlet manifold geometry have been suggested to achieve optimized swirl for the better mixing of fuel with air. The intake swirl intensities of modified cylinder head were measured in swirl test rig at different valve lifts. Later, the overall performance of 435 CC DI diesel engine was measured using modified cylinder head. In addition, the performance of engine was compared for both modified and old cylinder head. For same operating conditions, the brake power and brake specific fuel consumption was improved by 6% and 7% respectively with modified cylinder head compared to old cylinder head. The maximum brake power of 9 HP was achieved for modified cylinder head. The results revealed that the intake swirl has great influence on engine performance.

Performance and emission characteristics of the thermal barrier coated SI engine by adding argon inert gas to intake mixture

PubMed Central

Karthikeya Sharma, T.

2014-01-01

Dilution of the intake air of the SI engine with the inert gases is one of the emission control techniques like exhaust gas recirculation, water injection into combustion chamber and cyclic variability, without scarifying power output and/or thermal efficiency (TE). This paper investigates the effects of using argon (Ar) gas to mitigate the spark ignition engine intake air to enhance the performance and cut down the emissions mainly nitrogen oxides. The input variables of this study include the compression ratio, stroke length, and engine speed and argon concentration. Output parameters like TE, volumetric efficiency, heat release rates, brake power, exhaust gas temperature and emissions of NOx, CO2 and CO were studied in a thermal barrier coated SI engine, under variable argon concentrations. Results of this study showed that the inclusion of Argon to the input air of the thermal barrier coated SI engine has significantly improved the emission characteristics and engine’s performance within the range studied. PMID:26644918

Dedicated exhaust gas recirculation control systems and methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sczomak, David P.; Narayanaswamy, Kushal; Keating, Edward J.

An engine control system of a vehicle includes a fuel control module that controls fuel injection of a first cylinder of an engine based on a first target air/fuel ratio that is fuel lean relative to a stoichiometric air/fuel ratio and that controls fuel injection of a second cylinder of the engine based on a second target air/fuel ratio that is fuel rich relative to stoichiometry. The first cylinder outputs exhaust to a first three way catalyst (TWC), and the second cylinder outputs exhaust to an exhaust gas recirculation (EGR) valve. An EGR control module controls opening of the EGRmore » valve to: (i) a second TWC that reacts with nitrogen oxides (NOx) in the exhaust and outputs ammonia to a selective catalytic reduction (SCR) catalyst; and (ii) a conduit that recirculates exhaust back to an intake system of the engine.« less

40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2011 CFR

2011-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...

40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2012 CFR

2012-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...

Idling speed control system of an internal combustion engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyazaki, M.; Ishii, M.; Kako, H.

1986-09-16

This patent describes an idling speed control system of an internal combustion engine comprising: a valve device which controls the amount of intake air for the engine; an actuator which includes an electric motor for variably controlling the opening of the value device; rotation speed detector means for detecting the rotation speed of the engine; idling condition detector means for detecting the idling condition of the engine; feedback control means responsive to the detected output of the idling condition detector means for generating feedback control pulses to intermittently drive the electric motor so that the detected rotation speed of themore » engine under the idling condition may converge into a target idling rotation speed; and control means responsive to the output of detector means that detects an abnormally low rotation speed of the engine detected by the rotation speed detector means for generating control pulses that do not overlap the feedback control pulses to drive the electric motor in a predetermined direction.« less

Three-dimensional modeling of diesel engine intake flow, combustion and emissions-2

NASA Technical Reports Server (NTRS)

Reitz, R. D.; Rutland, C. J.

1993-01-01

A three-dimensional computer code, KIVA, is being modified to include state-of-the-art submodels for diesel engine flow and combustion. Improved and/or new submodels which have already been implemented and previously reported are: wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo'vich NO(x), and spray/wall impingement with rebounding and sliding drops. Progress on the implementation of improved spray drop drag and drop breakup models, the formulation and testing of a multistep kinetics ignition model, and preliminary soot modeling results are described. In addition, the use of a block structured version of KIVA to model the intake flow process is described. A grid generation scheme was developed for modeling realistic (complex) engine geometries, and computations were made of intake flow in the ports and combustion chamber of a two-intake-value engine. The research also involves the use of the code to assess the effects of subprocesses on diesel engine performance. The accuracy of the predictions is being tested by comparisons with engine experiments. To date, comparisons were made with measured engine cylinder pressure, temperature and heat flux data, and the model results are in good agreement with the experiments. Work is in progress that will allow validation of in-cylinder flow and soot formation predictions. An engine test facility is described that is being used to provide the needed validation data. Test results were obtained showing the effect of injection rate and split injections on engine performance and emissions.

40 CFR 90.416 - Intake air flow measurement specifications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Intake air flow measurement... Gaseous Exhaust Test Procedures § 90.416 Intake air flow measurement specifications. (a) If used, the engine intake air flow measurement method used must have a range large enough to accurately measure the...

Effects of Heat of Vaporization and Octane Sensitivity on Knock-Limited Spark Ignition Engine Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ratcliff, Matthew A; Burton, Jonathan L; Sindler, Petr

Knock-limited loads for a set of surrogate gasolines all having nominal 100 research octane number (RON), approximately 11 octane sensitivity (S), and a heat of vaporization (HOV) range of 390 to 595 kJ/kg at 25 degrees C were investigated. A single-cylinder spark-ignition engine derived from a General Motors Ecotec direct injection (DI) engine was used to perform load sweeps at a fixed intake air temperature (IAT) of 50 degrees C, as well as knock-limited load measurements across a range of IATs up to 90 degrees C. Both DI and pre-vaporized fuel (supplied by a fuel injector mounted far upstream ofmore » the intake valves and heated intake runner walls) experiments were performed to separate the chemical and thermal effects of the fuels' knock resistance. The DI load sweeps at 50 degrees C intake air temperature showed no effect of HOV on the knock-limited performance. The data suggest that HOV acts as a thermal contributor to S under the conditions studied. Measurement of knock-limited loads from the IAT sweeps for DI at late combustion phasing showed that a 40 vol% ethanol (E40) blend provided additional knock resistance at the highest temperatures, compared to a 20 vol% ethanol blend and hydrocarbon fuel with similar RON and S. Using the pre-vaporized fuel system, all the high S fuels produced nearly identical knock-limited loads at each temperature across the range of IATs studied. For these fuels RON ranged from 99.2 to 101.1 and S ranged from 9.4 to 12.2, with E40 having the lowest RON and highest S. The higher knock-limited loads for E40 at the highest IATs examined were consistent with the slightly higher S for this fuel, and the lower engine operating condition K values arising from use of this fuel. The study highlights how fuel HOV can affect the temperature at intake valve closing, and consequently the pressure-temperature history of the end gas leading to more negative values of K, thereby enhancing the effect of S on knock resistance.« less

Icing-Protection Requirements for Reciprocating-Engine Induction System

NASA Technical Reports Server (NTRS)

Coles, Willard D; Rollin, Vern G; Mulholland, Donald R

1950-01-01

Despite the development of relatively ice-free fuel-metering systems, the widespread use of alternate and heated-air intakes, and the use of alcohol for emergency de-icing, icing of aircraft-engine induction systems is a serious problem. Investigations have been made to study and to combat all phases of this icing problem. From these investigations, criterions for safe operation and for design of new induction systems have been established. The results were obtained from laboratory investigations of carburetor-supercharger combinations, wind-tunnel investigations of air scoops, multicylinder-engine studies, and flight investigations. Characteristics of three forms of ice, impact, throttling, and fuel evaporation were studied. The effects of several factors on the icing characteristics were also studied and included: (1) atmospheric conditions, (2) engine and air-scoop configurations, including light-airplane system, (3) type fuel used, and (4) operating variables, such as power condition, use of a manifold pressure regulator, mixture setting, carburetor heat, and water-alcohol injection. In addition, ice-detection methods were investigated and methods of preventing and removing induction-system ice were studied. Recommendations are given for design and operation with regard to induction-system design.

Apparatus for controlling air/fuel ratio for internal combustion engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kato, K.; Mizuno, T.

1986-07-08

This patent describes an apparatus for controlling air-fuel ratio of an air-fuel mixture to be supplied to an internal combustion engine having an intake passage, an exhaust passage, an an exhaust gas recirculation passage for recirculating exhaust gases in the exhaust passage to the intake passage therethrough. The apparatus consists of: (a) means for sensing rotational speed of the engine; (b) means for sensing intake pressure in the intake passage; (c) means for sensing atmospheric pressure; (d) means for enabling and disabling exhaust gas recirculation through the exhaust gas recirculation passage in accordance with operating condition of the engine; (e)more » means for determining required amount of fuel in accordance with the sensed rotational speed and the sensed intake pressure; (f) means for determining, when the exhaust gas recirculation is enabled, a first correction value in accordance with the sensed rotational speed, the sensed intake pressure and the sensed atmospheric pressure, the first correction factor being used for correcting fuel amount so as to compensate for the decrease of fuel due to the performance of exhaust gas recirculation and also to compensate for the change in atmospheric pressure; (g) means for determining, when the exhaust gas recirculation is disabled, a second correction value in accordance with the atmospheric pressure, the second correction factor being used so as to compensate for the change in atmospheric pressure; (h) means for correcting the required amount of fuel by the first correction value and the second correction value when the exhaust gas recirculation is enabled and disabled respectively; and (i) means for supplying the engine with the corrected amount of fuel.« less

Thermodynamic Cycle Analysis of Magnetohydrodynamic-Bypass Airbreathing Hypersonic Engines

NASA Technical Reports Server (NTRS)

Litchford, Ron J.; Bityurin, Valentine A.; Lineberry, John T.

1999-01-01

Established analyses of conventional ramjet/scramjet performance characteristics indicate that a considerable decrease in efficiency can be expected at off-design flight conditions. This can be explained, in large part, by the deterioration of intake mass flow and limited inlet compression at low flight speeds and by the onset of thrust degradation effects associated with increased burner entry temperature at high flight speeds. In combination, these effects tend to impose lower and upper Mach number limits for practical flight. It has been noted, however, that Magnetohydrodynamic (MHD) energy management techniques represent a possible means for extending the flight Mach number envelope of conventional engines. By transferring enthalpy between different stages of the engine cycle, it appears that the onset of thrust degradation may be delayed to higher flight speeds. Obviously, the introduction of additional process inefficiencies is inevitable with this approach, but it is believed that these losses are more than compensated through optimization of the combustion process. The fundamental idea is to use MHD energy conversion processes to extract and bypass a portion of the intake kinetic energy around the burner. We refer to this general class of propulsion system as an MHD-bypass engine. In this paper, we quantitatively assess the performance potential and scientific feasibility of MHD-bypass airbreathing hypersonic engines using ideal gasdynamics and fundamental thermodynamic principles.

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2011 CFR

2011-07-01

... suitable means for secure assembly, or shall meet the requirements for flanged metal-to-metal flame-proof... deterioration in service. It shall be so mounted in the equipment assembly that it is protected from accidental... that will arrest the propagation of an explosion and shall be so designed that improper assembly is...

30 CFR 36.23 - Engine intake system.

Code of Federal Regulations, 2010 CFR

2010-07-01

... suitable means for secure assembly, or shall meet the requirements for flanged metal-to-metal flame-proof... deterioration in service. It shall be so mounted in the equipment assembly that it is protected from accidental... that will arrest the propagation of an explosion and shall be so designed that improper assembly is...

Numerical Simulation Of Shock Response To Wall Changes In High Speed Intakes

NASA Astrophysics Data System (ADS)

Fincham, J.; Taylor, N. V.

2011-05-01

Hypersonic flight presents a number of challenges to the designer, one of which is the intake behaviour. Minimising drag requires careful positioning of the intake shock structure, while accurate understanding of the dynamic behaviour is required to allow minimisation of margins. In this paper, a two shock external compression intake derived from the Reaction Engines Limited SABRE engine is examined using inviscid axisymmetric CFD analysis to determine the response of the normal shockwave to axial motion of the intake centrebody. An approximately linear relationship between centrebody position and both the normal shock position and additive drag in steady flow is demonstrated. Initial results from an unsteady analysis are also given, which show complex behaviours may be triggered by rapid motion of the centrebody in response to control input.

High-Speed Multiplexed Spatiotemporally Resolved Measurements of Exhaust Gas Recirculation Dynamics in a Multi-Cylinder Engine Using Laser Absorption Spectroscopy.

PubMed

Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

2016-04-01

The need for more environmentally friendly and efficient energy conversion is of paramount importance in developing and designing next-generation internal combustion (IC) engines for transportation applications. One effective solution to reducing emissions of mono-nitrogen oxides (NOx) is exhaust gas recirculation (EGR), which has been widely implemented in modern vehicles. However, cylinder-to-cylinder and cycle-to-cycle variations in the charge-gas uniformity can be a major barrier to optimum EGR implementation on multi-cylinder engines, and can limit performance, stability, and efficiency. Precise knowledge and fine control over the EGR system is therefore crucial, particularly for optimizing advanced engine concepts such as reactivity controlled compression ignition (RCCI). An absorption-based laser diagnostic was developed to study spatiotemporal charge-gas distributions in an IC engine intake manifold in real-time. The laser was tuned to an absorption band of carbon dioxide (CO2), a standard exhaust-gas marker, near 2.7 µm. The sensor was capable of probing four separate measurement locations simultaneously, and independently analyzing EGR fraction at speeds of 5 kHz (1.2 crank-angle degree (CAD) at 1 k RPM) or faster with high accuracy. The probes were used to study spatiotemporal EGR non-uniformities in the intake manifold and ultimately promote the development of more efficient and higher performance engines. © The Author(s) 2016.

Development and modification of a single overhead camshaft 4-valve 4-stroke 135 cc formula varsity race car engine

NASA Astrophysics Data System (ADS)

Abdullah, M. A.; Tamaldin, N.; Rusnandi, H.; Manoharan, T.; Samsir, M. A.

2013-12-01

The engine that was chosen to be developed and modified is Yamaha LC 135 Single Overhead Camshaft (SOHC) 4-valve 4-stroke 135cc liquid-cooled engine. The engine selection is based on the specification, rule and regulation in UTeM Formula Varsity 2012 (FV 2012). The engine performance is determined by engine operating characteristics. The engine air flow affects the filtration, intake and exhaust systems. The heat from the engine rejected to the surrounding through the active cooling system which has radiator and fan. The selection of the engine is based on weighted decision matrix which consists of reliability, operating and maintenance cost, fuel consumption and weight. The score of the matrix is formulated based on relative weighted factor among the selections. It been compared between Yamaha LC 135 Single Overhead Camshaft (SOHC) 4-valve 4-stroke 135cc liquid-cooled engine, Honda Wave 125 X Air Cooled, 4 Cycle Engine Overhead Camshaft (OHC) and Suzuki Shogun RR 4 stroke air cooled Single Overhead Camshaft (SOHC). The modification is applied to the engine through the simulation and tuning of Capacitor Discharge Ignition (CDI).

Research on cylinder processes of gasoline homogenous charge compression ignition (HCCI) engine

NASA Astrophysics Data System (ADS)

Cofaru, Corneliu

2017-10-01

This paper is designed to develop a HCCI engine starting from a spark ignition engine platform. The engine test was a single cylinder, four strokes provided with carburetor. The results of experimental research on this version were used as a baseline for the next phase of the work. After that, the engine was modified for a HCCI configuration, the carburetor was replaced by a direct fuel injection system in order to control precisely the fuel mass per cycle taking into account the measured intake air-mass. To ensure that the air - fuel mixture auto ignite, the compression ratio was increased from 9.7 to 11.5. The combustion process in HCCI regime is governed by chemical kinetics of mixture of air-fuel, rein ducted or trapped exhaust gases and fresh charge. To modify the quantities of trapped burnt gases, the exchange gas system was changed from fixed timing to variable valve timing. To analyze the processes taking place in the HCCI engine and synthesizing a control system, a model of the system which takes into account the engine configuration and operational parameters are needed. The cylinder processes were simulated on virtual model. The experimental research works were focused on determining the parameters which control the combustion timing of HCCI engine to obtain the best energetic and ecologic parameters.

Dna Sequencing

DOEpatents

Hetrick, Robert Eugene; Hilbert, Harold Sean; Parsons, Michael Howard; Stockhausen, William Francis

1997-10-07

A fuel injection system used in the intake air passageway of an internal combustion engine has a strategy for reducing cold start hydrocarbon emissions. The fuel injector has an actuator which allows the fuel spray pattern to be varied from one which is widely dispersed and atomized to one which is only weakly dispersed. A strategy for varying the spray pattern during the engine warm-up period after cold start is disclosed. The strategy increases evaporation within the passageway so that cold start overfuelling and attendant hydrocarbon emissions are reduced.

40 CFR 1065.325 - Intake-flow calibration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Section 1065.325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Flow-Related Measurements § 1065.325 Intake-flow calibration. (a) Calibrate intake-air flow meters upon initial installation. Follow the...

Fast spatially resolved exhaust gas recirculation (EGR) distribution measurements in an internal combustion engine using absorption spectroscopy.

PubMed

Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E; Perfetto, Anthony; Geckler, Sam; Partridge, William P

2015-09-01

Exhaust gas recirculation (EGR) in internal combustion engines is an effective method of reducing NOx emissions while improving efficiency. However, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder non-uniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. A sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO2 concentration at various locations in the intake manifold. The study employed mid-infrared light sources tuned to an absorption band of CO2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.

Fast Spatially Resolved Exhaust Gas Recirculation (EGR) Distribution Measurements in an Internal Combustion Engine Using Absorption Spectroscopy

DOE PAGES

Yoo, Jihyung; Prikhodko, Vitaly; Parks, James E.; ...

2015-09-01

One effective method of reducing NO x emissions while improving efficiency is exhaust gas recirculation (EGR) in internal combustion engines. But, insufficient mixing between fresh air and exhaust gas can lead to cycle-to-cycle and cylinder-to-cylinder nonuniform charge gas mixtures of a multi-cylinder engine, which can in turn reduce engine performance and efficiency. Furthermore, a sensor packaged into a compact probe was designed, built and applied to measure spatiotemporal EGR distributions in the intake manifold of an operating engine. The probe promotes the development of more efficient and higher-performance engines by resolving high-speed in situ CO 2 concentration at various locationsmore » in the intake manifold. Our study employed mid-infrared light sources tuned to an absorption band of CO 2 near 4.3 μm, an industry standard species for determining EGR fraction. The calibrated probe was used to map spatial EGR distributions in an intake manifold with high accuracy and monitor cycle-resolved cylinder-specific EGR fluctuations at a rate of up to 1 kHz.« less

Engine Cylinder Temperature Control

DOEpatents

Kilkenny, Jonathan Patrick; Duffy, Kevin Patrick

2005-09-27

A method and apparatus for controlling a temperature in a combustion cylinder in an internal combustion engine. The cylinder is fluidly connected to an intake manifold and an exhaust manifold. The method and apparatus includes increasing a back pressure associated with the exhaust manifold to a level sufficient to maintain a desired quantity of residual exhaust gas in the cylinder, and varying operation of an intake valve located between the intake manifold and the cylinder to an open duration sufficient to maintain a desired quantity of fresh air from the intake manifold to the cylinder, wherein controlling the quantities of residual exhaust gas and fresh air are performed to maintain the temperature in the cylinder at a desired level.

A computer simulation of the turbocharged turbo compounded diesel engine system: A description of the thermodynamic and heat transfer models

NASA Technical Reports Server (NTRS)

Assanis, D. N.; Ekchian, J. E.; Frank, R. M.; Heywood, J. B.

1985-01-01

A computer simulation of the turbocharged turbocompounded direct-injection diesel engine system was developed in order to study the performance characteristics of the total system as major design parameters and materials are varied. Quasi-steady flow models of the compressor, turbines, manifolds, intercooler, and ducting are coupled with a multicylinder reciprocator diesel model, where each cylinder undergoes the same thermodynamic cycle. The master cylinder model describes the reciprocator intake, compression, combustion and exhaust processes in sufficient detail to define the mass and energy transfers in each subsystem of the total engine system. Appropriate thermal loading models relate the heat flow through critical system components to material properties and design details. From this information, the simulation predicts the performance gains, and assesses the system design trade-offs which would result from the introduction of selected heat transfer reduction materials in key system components, over a range of operating conditions.

Design and Simulation of a Pressure Wave Supercharger for a Small Two-Stroke Engine

DTIC Science & Technology

2014-03-27

Air at ambient pressure is passed through the compressor where the pressure is increased with the intended purpose of increasing the overall mass flow...rate of air to the intake manifold. For a small two-stroke engine that has little excess energy to spare for the operation of a compressor , the...exhaust gasses from the engine to drive a turbine that is linked via a shaft to a centrifugal compressor which feeds compressed air to the intake

Method and apparatus for controlling fuel/air mixture in a lean burn engine

DOEpatents

Kubesh, John Thomas; Dodge, Lee Gene; Podnar, Daniel James

1998-04-07

The system for controlling the fuel/air mixture supplied to a lean burn engine when operating on natural gas, gasoline, hydrogen, alcohol, propane, butane, diesel or any other fuel as desired. As specific humidity of air supplied to the lean burn engine increases, the oxygen concentration of exhaust gas discharged by the engine for a given equivalence ratio will decrease. Closed loop fuel control systems typically attempt to maintain a constant exhaust gas oxygen concentration. Therefore, the decrease in the exhaust gas oxygen concentration resulting from increased specific humidity will often be improperly attributed to an excessive supply of fuel and the control system will incorrectly reduce the amount of fuel supplied to the engine. Also, the minimum fuel/air equivalence ratio for a lean burn engine to avoid misfiring will increase as specific humidity increases. A relative humidity sensor to allow the control system to provide a more enriched fuel/air mixture at high specific humidity levels. The level of specific humidity may be used to compensate an output signal from a universal exhaust gas oxygen sensor for changing oxygen concentrations at a desired equivalence ratio due to variation in specific humidity specific humidity. As a result, the control system will maintain the desired efficiency, low exhaust emissions and power level for the associated lean burn engine regardless of the specific humidity level of intake air supplied to the lean burn engine.

Method and apparatus for PM filter regeneration

DOEpatents

Opris, Cornelius N [Peoria, IL; Verkiel, Maarten [Metamora, IL

2006-01-03

A method and apparatus for initiating regeneration of a particulate matter (PM) filter in an exhaust system in an internal combustion engine. The method and apparatus includes determining a change in pressure of exhaust gases passing through the PM filter, and responsively varying an opening of an intake valve in fluid communication with a combustion chamber.

40 CFR 1068.261 - What provisions apply for selling or shipping certified engines that are not yet in the certified...

Code of Federal Regulations, 2010 CFR

2010-07-01

... without air filters or other portions of the air intake system that are specifically identified by part... appropriate aftertreatment device and/or air filter, but without completing the assembly with all the... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS GENERAL...

40 CFR 1068.261 - What provisions apply for selling or shipping certified engines that are not yet in the certified...

Code of Federal Regulations, 2011 CFR

2011-07-01

... without air filters or other portions of the air intake system that are specifically identified by part... appropriate aftertreatment device and/or air filter, but without completing the assembly with all the... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS GENERAL...

Propane-Fueled Jet Engine

NASA Astrophysics Data System (ADS)

Farwell, D. A.; Svenson, A. J.; Ramsier, R. D.

2001-04-01

We present our recent efforts to design, construct, and test a gas turbine, or jet, engine. Our design utilizes a turbocharger and ignition system from an automobile, and a flame tube/reaction chamber unit fabricated by hand from stainless steel. Once the engine is running, it is completely self-sustaining as long as there is a fuel supply, which in our case is propane. Air is forced into the intake where it is compressed and then injected into the combustion chamber where it is mixed with propane. The spark plugs ignite the air-propane mixture which burns to produce thrust at the exhaust. We have performed operational tests under different environmental conditions and with several turbochargers. We are currently working on adding a lubrication system to the engine, and will discuss our plan to experiment with the reaction chamber and flame tube design in an effort to improve performance and efficiency. *Corresponding author: rex@uakron.edu

Thermoelectric system

DOEpatents

Reiners, Eric A.; Taher, Mahmoud A.; Fei, Dong; McGilvray, Andrew N.

2007-10-30

In one particular embodiment, an internal combustion engine is provided. The engine comprises a block, a head, a piston, a combustion chamber defined by the block, the piston, and the head, and at least one thermoelectric device positioned between the combustion chamber and the head. In this particular embodiment, the thermoelectric device is in direct contact with the combustion chamber. In another particular embodiment, a cylinder head configured to sit atop a cylinder bank of an internal combustion engine is provided. The cylinder head comprises a cooling channel configured to receive cooling fluid, valve seats configured for receiving intake and exhaust valves, and thermoelectric devices positioned around the valve seats.

Adaptive individual-cylinder thermal state control using intake air heating for a GDCI engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roth, Gregory T.; Sellnau, Mark C.

A system for a multi-cylinder compression ignition engine includes a plurality of heaters, at least one heater per cylinder, with each heater configured to heat air introduced into a cylinder. Independent control of the heaters is provided on a cylinder-by-cylinder basis. A combustion parameter is determined for combustion in each cylinder of the engine, and control of the heater for that cylinder is based on the value of the combustion parameter for combustion in that cylinder. A method for influencing combustion in a multi-cylinder compression ignition engine, including determining a combustion parameter for combustion taking place in a cylinder ofmore » the engine and controlling a heater configured to heat air introduced into that cylinder, is also provided.« less

40 CFR 1065.225 - Intake-air flow meter.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

40 CFR 1065.225 - Intake-air flow meter.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

40 CFR 1065.225 - Intake-air flow meter.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Intake-air flow meter. 1065.225 Section 1065.225 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments Flow-Related Measurements § 1065.225 Intake-air...

Stratified charge rotary engine - Internal flow studies at the MSU engine research laboratory

NASA Technical Reports Server (NTRS)

Hamady, F.; Kosterman, J.; Chouinard, E.; Somerton, C.; Schock, H.; Chun, K.; Hicks, Y.

1989-01-01

High-speed visualization and laser Doppler velocimetry (LDV) systems consisting of a 40-watt copper vapor laser, mirrors, cylindrical lenses, a high speed camera, a synchronization timing system, and a particle generator were developed for the study of the fuel spray-air mixing flow characteristics within the combustion chamber of a motored rotary engine. The laser beam is focused down to a sheet approximately 1 mm thick, passing through the combustion chamber and illuminates smoke particles entrained in the intake air. The light scattered off the particles is recorded by a high speed rotating prism camera. Movies are made showing the air flow within the combustion chamber. The results of a movie showing the development of a high-speed (100 Hz) high-pressure (68.94 MPa, 10,000 psi) fuel jet are also discussed. The visualization system is synchronized so that a pulse generated by the camera triggers the laser's thyratron.

Anti-air pollution & energy conservation system for automobiles using leaded or unleaded gasoline, diesel or alternate fuel

DOEpatents

Bose, Ranendra K.

2002-06-04

Exhaust gases from an internal combustion engine operating with leaded or unleaded gasoline or diesel or natural gas, are used for energizing a high-speed gas turbine. The convoluting gas discharge causes a first separation stage by stratifying of heavier and lighter exhaust gas components that exit from the turbine in opposite directions, the heavier components having a second stratifying separation in a vortex tube to separate combustible pollutants from non-combustible components. The non-combustible components exit a vortex tube open end to atmosphere. The lighter combustible, pollutants effected in the first separation are bubbled through a sodium hydroxide solution for dissolving the nitric oxide, formaldehyde impurities in this gas stream before being piped to the engine air intake for re-combustion, thereby reducing the engine's exhaust pollution and improving its fuel economy. The combustible, heavier pollutants from the second separation stage are piped to air filter assemblies. This gas stream convoluting at a high-speed through the top stator-vanes of the air filters, centrifugally separates the coalescent water, aldehydes, nitrogen dioxides, sulfates, sulfur, lead particles which collect at the bottom of the bowl, wherein it is periodically released to the roadway. Whereas, the heavier hydrocarbon, carbon particles are piped through the air filter's porous element to the engine air intake for re-combustion, further reducing the engine's exhaust pollution and improving its fuel economy.

Development of a novel passive top-down uniflow scavenged two-stroke GDI engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ciccarelli, G.; Reynolds, Steve; Oliver, Phillip

2010-02-15

The design and performance characteristics of a novel top-down uniflow scavenged gasoline direct-injection two-stroke engine are presented. The novelty of the engine lies in the cylinder head that contains multiple check valves that control scavenging airflow into the cylinder from a supercharged air plenum. When the cylinder pressure drops below the intake plenum pressure during the expansion stroke, air flows into the cylinder through the check valves. During compression the cylinder pressure increases to a level above the intake plenum pressure and the check valves close preventing back-flow into the intake plenum. The engine head design provides asymmetrical intake valvemore » timing without the use of poppet valves and the associated valve-train. In combination with an external Roots-type supercharger that supplies the plenum and exhaust ports at the bottom of the cylinder wall, the novel head provides top-down uniflow air scavenging. Motoring tests indicated that the check valves seal and the peak pressure is governed by the compression ratio. The only drawback observed is that valve closing is delayed as the engine speed increases. In order to investigate the valve dynamics, additional tests were performed in an optically-accessible cold flow test rig that enabled the direct measurement of valve opening and closing time under various conditions. (author)« less

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2011 CFR

2011-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2010 CFR

2010-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2013 CFR

2013-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2012 CFR

2012-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

40 CFR 1065.122 - Engine cooling and lubrication.

Code of Federal Regulations, 2014 CFR

2014-07-01

....122 Section 1065.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Equipment Specifications § 1065.122 Engine cooling and lubrication. (a) Engine cooling. Cool the engine during testing so its intake-air, oil, coolant, block, and...

Effect of intake pipe on the volumetric efficiency of an internal combustion engine

NASA Technical Reports Server (NTRS)

Capetti, Antonio

1929-01-01

The writer discusses the phenomena of expansion and compression which alternately take place in the cylinders of four-stroke engines during the induction process at a high mean piston speed due to the inertia and elasticity of the mixture in the intake pipe. The present paper is intended to demonstrate theoretically the existence of a most favorable pipe length for charging.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jatana, Gurneesh; Geckler, Sam; Koeberlein, David

We designed and developed a 4-probe multiplexed multi-species absorption spectroscopy sensor system for gas property measurements on the intake side of commercial multi-cylinder internal-combustion (I.C.) engines; the resulting cycle- and cylinder-resolved concentration, temperature and pressure measurements are applicable for assessing spatial and temporal variations in the recirculated exhaust gas (EGR) distribution at various locations along the intake gas path, which in turn is relevant to assessing cylinder charge uniformity, control strategies, and CFD models. Furthermore, the diagnostic is based on absorption spectroscopy and includes an H 2O absorption system (utilizing a 1.39 m distributed feedback (DFB) diode laser) for measuringmore » gas temperature, pressure, and H 2O concentration, and a CO 2 absorption system (utilizing a 2.7 m DFB laser) for measuring CO 2 concentration. The various lasers, optical components and detectors were housed in an instrument box, and the 1.39- m and 2.7- m lasers were guided to and from the engine-mounted probes via optical fibers and hollow waveguides, respectively. The 5kHz measurement bandwidth allows for near-crank angle resolved measurements, with a resolution of 1.2 crank angle degrees at 1000 RPM. Our use of compact stainless steel measurement probes enables simultaneous multi-point measurements at various locations on the engine with minimal changes to the base engine hardware; in addition to resolving large-scale spatial variations via simultaneous multi-probe measurements, local spatial gradients can be resolved by translating individual probes. Along with details of various sensor design features and performance, we also demonstrate validation of the spectral parameters of the associated CO 2 absorption transitions using both a multi-pass heated cell and the sensor probes.« less

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2011 CFR

2011-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2010 CFR

2010-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

30 CFR 7.101 - Surface temperature tests.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in the application, § 7.97(a)(3). (iii) If a wet exhaust conditioner is used to cool the exhaust gas... temperature tests. The test for determination of exhaust gas cooling efficiency described in § 7.102 may be..., by volume, of methane in the intake air mixture until all parts of the engine, exhaust coolant system...

Study of intake manifold for Universiti Malaysia Perlis automotive racing team formula student race car

NASA Astrophysics Data System (ADS)

Norizan, A.; Rahman, M. T. A.; Amin, N. A. M.; Basha, M. H.; Ismail, M. H. N.; Hamid, A. F. A.

2017-10-01

This paper describes the design differences between the intake manifold and restrictor used in racing cars that participate in the Formula Student (FSAE) competition. To fulfil the criteria of rules and regulation of the race, each race car must have a restriction device that has a maximum diameter of 20 mm installed between the throttle body and intake manifold. To overcome these problems, a restrictor has been designed and analysed using the steady state analysis, to reduce the loss of pressure in the restrictor. Design of the restrictor has a fixed parameter of the maximum diameter of 20mm. There are some differences that have been taken to make the comparison between the design of the restrictor, the diameter of the inlet and outlet, the curvature of the surface, convergence and divergence angle and length of the restrictor. Intake manifold was designed based on the design of the chassis, which shall not exceed the envelope defined by the FSAE competition. A good intake manifold design will affect the performance of the engine. Each design have made an analysis designed to ensure that each cylinder engine gets its air evenly. To verify the design, steady state analysis was made for a total mass flow rate and the velocity of air leaving a runner in each engine. Data such as the engine MAP reading was recorded by using Haltech ECU Management Software as reference purposes.

1. View from south to north of perimeter acquisition radar ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. View from south to north of perimeter acquisition radar power plant diesel engine exhaust and the small engine intake. On the right is the ventilating air intake/exhaust, distinguishable by its square shape, whereas the diesel columns are rectangular - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Power Plant, In Limited Access Area, Southwest of PARB at end of Service Road B, Nekoma, Cavalier County, ND

In-cylinder air-flow characteristics of different intake port geometries using tomographic PIV

NASA Astrophysics Data System (ADS)

Agarwal, Avinash Kumar; Gadekar, Suresh; Singh, Akhilendra Pratap

2017-09-01

For improving the in-cylinder flow characteristics of intake air/charge and for strengthening the turbulence intensity, specific intake port geometries have shown significant potential in compression ignition engines. In this experimental study, effects of intake port geometries on air-flow characteristics were investigated using tomographic particle imaging velocimetry (TPIV). Experiments were performed using three experimental conditions, namely, swirl port open (SPO), tangential port open (TPO), and both port open (BPO) configurations in a single cylinder optical research engine. Flow investigations were carried out in a volumetric section located in the middle of the intake and exhaust valves. Particle imaging velocimetry (PIV) images were captured using two high speed cameras at a crank angle resolution of 2° in the intake and compression strokes. The captured PIV images were then pre-processed and post-processed to obtain the final air-flow-field. Effects of these two intake ports on flow-field are presented for air velocity, vorticity, average absolute velocity, and turbulent kinetic energy. Analysis of these flow-fields suggests the dominating nature of the swirl port over the tangential port for the BPO configuration and higher rate of flow energy dissipation for the TPO configuration compared to the SPO and BPO configurations. These findings of TPIV investigations were experimentally verified by combustion and particulate characteristics of the test engine in thermal cylinder head configuration. Combustion results showed that the SPO configuration resulted in superior combustion amongst all three port configurations. Particulate characteristics showed that the TPO configuration resulted in higher particulate compared to other port configurations.

Simultaneous high-speed gas property measurements at the exhaust gas recirculation cooler exit and at the turbocharger inlet of a multicylinder diesel engine using diode-laser-absorption spectroscopy.

PubMed

Jatana, Gurneesh S; Magee, Mark; Fain, David; Naik, Sameer V; Shaver, Gregory M; Lucht, Robert P

2015-02-10

A diode-laser-absorption-spectroscopy-based sensor system was used to perform high-speed (100 Hz to 5 kHz) measurements of gas properties (temperature, pressure, and H(2)O vapor concentration) at the turbocharger inlet and at the exhaust gas recirculation (EGR) cooler exit of a diesel engine. An earlier version of this system was previously used for high-speed measurements of gas temperature and H(2)O vapor concentration in the intake manifold of the diesel engine. A 1387.2 N m tunable distributed feedback diode laser was used to scan across multiple H(2)O absorption transitions, and the direct absorption signal was recorded using a high-speed data acquisition system. Compact optical connectors were designed to conduct simultaneous measurements in the intake manifold, the EGR cooler exit, and the turbocharger inlet of the engine. For measurements at the turbocharger inlet, these custom optical connectors survived gas temperatures as high as 800 K using a simple and passive arrangement in which the temperature-sensitive components were protected from high temperatures using ceramic insulators. This arrangement reduced system cost and complexity by eliminating the need for any active water or oil cooling. Diode-laser measurements performed during steady-state engine operation were within 5% of the thermocouple and pressure sensor measurements, and within 10% of the H(2)O concentration values derived from the CO(2) gas analyzer measurements. Measurements were also performed in the engine during transient events. In one such transient event, where a step change in fueling was introduced, the diode-laser sensor was able to capture the 30 ms change in the gas properties; the thermocouple, on the other hand, required 7.4 s to accurately reflect the change in gas conditions, while the gas analyzer required nearly 600 ms. To the best of our knowledge, this is the first implementation of such a simple and passive arrangement of high-temperature optical connectors as well as the first documented application of diode-laser absorption for high-speed gas dynamics measurements in the turbocharger inlet and EGR cooler exit of a diesel engine.

40 CFR 92.204 - Designation of engine families.

Code of Federal Regulations, 2010 CFR

2010-07-01

... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5... shutters, etc.); (3) The approximate bore and stroke dimensions; (4) The approximate location of the intake...

40 CFR 92.204 - Designation of engine families.

Code of Federal Regulations, 2013 CFR

2013-07-01

... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5... shutters, etc.); (3) The approximate bore and stroke dimensions; (4) The approximate location of the intake...

40 CFR 1033.230 - Grouping locomotives into engine families.

Code of Federal Regulations, 2013 CFR

2013-07-01

... nominal bore and stroke dimensions. (4) The approximate intake and exhaust event timing and duration... approximate bore and stroke dimensions. (4) The approximate location of the intake and exhaust valves (or...

40 CFR 92.204 - Designation of engine families.

Code of Federal Regulations, 2012 CFR

2012-07-01

... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5... shutters, etc.); (3) The approximate bore and stroke dimensions; (4) The approximate location of the intake...

40 CFR 92.204 - Designation of engine families.

Code of Federal Regulations, 2014 CFR

2014-07-01

... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5... shutters, etc.); (3) The approximate bore and stroke dimensions; (4) The approximate location of the intake...

40 CFR 92.204 - Designation of engine families.

Code of Federal Regulations, 2011 CFR

2011-07-01

... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5... shutters, etc.); (3) The approximate bore and stroke dimensions; (4) The approximate location of the intake...

Intake flow modeling in a four stroke diesel using KIVA3

NASA Technical Reports Server (NTRS)

Hessel, R. P.; Rutland, C. J.

1993-01-01

Intake flow for a dual intake valved diesel engine is modeled using moving valves and realistic geometries. The objectives are to obtain accurate initial conditions for combustion calculations and to provide a tool for studying intake processes. Global simulation parameters are compared with experimental results and show good agreement. The intake process shows a 30 percent difference in mass flows and average swirl in opposite directions across the two intake valves. The effect of the intake process on the flow field at the end of compression is examined. Modeling the intake flow results in swirl and turbulence characteristics that are quite different from those obtained by conventional methods in which compression stroke initial conditions are assumed.

An Ejector Air Intake Design Method for a Novel Rocket-Based Combined-Cycle Rocket Nozzle

NASA Astrophysics Data System (ADS)

Waung, Timothy S.

Rocket-based combined-cycle (RBCC) vehicles have the potential to reduce launch costs through the use of several different air breathing engine cycles, which reduce fuel consumption. The rocket-ejector cycle, in which air is entrained into an ejector section by the rocket exhaust, is used at flight speeds below Mach 2. This thesis develops a design method for an air intake geometry around a novel RBCC rocket nozzle design for the rocket-ejector engine cycle. This design method consists of a geometry creation step in which a three-dimensional intake geometry is generated, and a simple flow analysis step which predicts the air intake mass flow rate. The air intake geometry is created using the rocket nozzle geometry and eight primary input parameters. The input parameters are selected to give the user significant control over the air intake shape. The flow analysis step uses an inviscid panel method and an integral boundary layer method to estimate the air mass flow rate through the intake geometry. Intake mass flow rate is used as a performance metric since it directly affects the amount of thrust a rocket-ejector can produce. The design method results for the air intake operating at several different points along the subsonic portion of the Ariane 4 flight profile are found to under predict mass flow rate by up to 8.6% when compared to three-dimensional computational fluid dynamics simulations for the same air intake.

Impact of Formaldehyde Addition on Auto-Ignition in Internal-Combustion Engines

NASA Astrophysics Data System (ADS)

Kuwahara, Kazunari; Ando, Hiromitsu; Furutani, Masahiro; Ohta, Yasuhiko

By employing a direct-injection diesel engine equipped with a common-rail type of injection system, by adding formaldehyde (CH2O) to the intake air, and by changing the fuel-injection timing, the compression ratio and the intake-air temperature, a mechanism for CH2O as a fuel additive to affect auto-ignition was discussed. Unlike an HCCI type of engine, the diesel engine can expose an air-fuel mixture only to a limited range of the in-cylinder temperature before the ignition, and can separate low- and high-temperature parts of the mechanism. When low-temperature oxidation starts at a temperature above 900K, there are cases that the CH2O advances the ignition timing. Below 900K, to the contrary, it always retards the timing. It is because, above 900K, a part of the CH2O changes into CO together with H2O2 as an ignition promoter. Below 900K, on the other hand, the CH2O itself acts as an OH radical scavenger against cool-flame reaction, from the beginning of low-temperature oxidation. Then, the engine was modified for its extraordinary function as a gasoline-knocking generator, in order that an effect of CH2O on knocking could be discussed. The CH2O retards the onset of auto-ignition of an end gas. Judging from a large degree of the retardation, the ignition is probably triggered below 900K.

LCD OF AIR INTAKE MANIFOLDS PHASE 2: FORD F250 AIR INTAKE MANIFOLD

EPA Science Inventory

The life cycle design methodology was applied to the design analysis of three alternatives for the lower plehum of the air intake manifold for us with a 5.4L F-250 truck engine: a sand cast aluminum, a lost core molded nylon composite, and a vibration welded nylon composite. The ...

Fundamental Interactions in Gasoline Compression Ignition Engines with Fuel Stratification

NASA Astrophysics Data System (ADS)

Wolk, Benjamin Matthew

Transportation accounted for 28% of the total U.S. energy demand in 2011, with 93% of U.S. transportation energy coming from petroleum. The large impact of the transportation sector on global climate change necessitates more-efficient, cleaner-burning internal combustion engine operating strategies. One such strategy that has received substantial research attention in the last decade is Homogeneous Charge Compression Ignition (HCCI). Although the efficiency and emissions benefits of HCCI are well established, practical limits on the operating range of HCCI engines have inhibited their application in consumer vehicles. One such limit is at high load, where the pressure rise rate in the combustion chamber becomes excessively large. Fuel stratification is a potential strategy for reducing the maximum pressure rise rate in HCCI engines. The aim is to introduce reactivity gradients through fuel stratification to promote sequential auto-ignition rather than a bulk-ignition, as in the homogeneous case. A gasoline-fueled compression ignition engine with fuel stratification is termed a Gasoline Compression Ignition (GCI) engine. Although a reasonable amount of experimental research has been performed for fuel stratification in GCI engines, a clear understanding of how the fundamental in-cylinder processes of fuel spray evaporation, mixing, and heat release contribute to the observed phenomena is lacking. Of particular interest is gasoline's pressure sensitive low-temperature chemistry and how it impacts the sequential auto-ignition of the stratified charge. In order to computationally study GCI with fuel stratification using three-dimensional computational fluid dynamics (CFD) and chemical kinetics, two reduced mechanisms have been developed. The reduced mechanisms were developed from a large, detailed mechanism with about 1400 species for a 4-component gasoline surrogate. The two versions of the reduced mechanism developed in this work are: (1) a 96-species version and (2) a 98-species version including nitric oxide formation reactions. Development of reduced mechanisms is necessary because the detailed mechanism is computationally prohibitive in three-dimensional CFD and chemical kinetics simulations. Simulations of Partial Fuel Stratification (PFS), a GCI strategy, have been performed using CONVERGE with the 96-species reduced mechanism developed in this work for a 4-component gasoline surrogate. Comparison is made to experimental data from the Sandia HCCI/GCI engine at a compression ratio 14:1 at intake pressures of 1 bar and 2 bar. Analysis of the heat release and temperature in the different equivalence ratio regions reveals that sequential auto-ignition of the stratified charge occurs in order of increasing equivalence ratio for 1 bar intake pressure and in order of decreasing equivalence ratio for 2 bar intake pressure. Increased low- and intermediate-temperature heat release with increasing equivalence ratio at 2 bar intake pressure compensates for decreased temperatures in higher-equivalence ratio regions due to evaporative cooling from the liquid fuel spray and decreased compression heating from lower values of the ratio of specific heats. The presence of low- and intermediate-temperature heat release at 2 bar intake pressure alters the temperature distribution of the mixture stratification before hot-ignition, promoting the desired sequential auto-ignition. At 1 bar intake pressure, the sequential auto-ignition occurs in the reverse order compared to 2 bar intake pressure and too fast for useful reduction of the maximum pressure rise rate compared to HCCI. Additionally, the premixed portion of the charge auto-ignites before the highest-equivalence ratio regions. Conversely, at 2 bar intake pressure, the premixed portion of the charge auto-ignites last, after the higher-equivalence ratio regions. More importantly, the sequential auto-ignition occurs over a longer time period for 2 bar intake pressure than at 1 bar intake pressure such that a sizable reduction in the maximum pressure rise rate compared to HCCI can be achieved.

Temperature field measurement research in high-speed diesel engine using laser induced fluorescence technology

NASA Astrophysics Data System (ADS)

Liu, Yongfeng; Zhang, You-tong; Gou, Chenhua; Tian, Hongsen

2008-12-01

Temperature laser- induced- fluorescence (LIF) 2-D imaging measurements using a new multi-spectral detection strategy are reported for high pressure flames in high-speed diesel engine. Schematic of the experimental set-up is outlined and the experimental data on the diesel engine is summarized. Experiment injection system is a third generation Bosch high-pressure common rail featuring a maximum pressure of 160 MPa. The injector is equipped with a six-hole nozzle, where each hole has a diameter of 0.124 mm. and slightly offset (by 1.0 mm) to the center of the cylinder axis to allow a better cooling of the narrow bridge between the exhaust valves. The measurement system includes a blower, which supplied the intake flow rate, and a prototype single-valve direct injection diesel engine head modified to lay down the swirled-type injector. 14-bit digital CCD cameras are employed to achieve a greater level of accuracy in comparison to the results of previous measurements. The temperature field spatial distributions in the cylinder for different crank angle degrees are carried out in a single direct-injection diesel engine.

2D temperature field measurement in a direct-injection engine using LIF technology

NASA Astrophysics Data System (ADS)

Liu, Yongfeng; Tian, Hongsen; Yang, Jianwei; Sun, Jianmin; Zhu, Aihua

2011-12-01

A new multi-spectral detection strategy for temperature laser- induced- fluorescence (LIF) 2-D imaging measurements is reported for high pressure flames in high-speed diesel engine. Schematic of the experimental set-up is outlined and the experimental data on the diesel engine is summarized. Experiment injection system is a third generation Bosch high-pressure common rail featuring a maximum pressure of 160MPa. The injector is equipped with a six-hole nozzle, where each hole has a diameter of 0.124 mm. and slightly offset to the center of the cylinder axis to allow a better cooling of the narrow bridge between the exhaust valves. The measurement system includes a blower, which supplied the intake flow rate, and a prototype single-valve direct injection diesel engine head modified to lay down the swirled-type injector. 14-bit digital CCD cameras are employed to achieve a greater level of accuracy in comparison to the results of previous measurements. The temperature field spatial distributions in the cylinder for different crank angle degrees are carried out in a single direct-injection diesel engine.

Diesel NO(x) aftertreatment by combined process using temperature swing adsorption, NO(x) reduction by nonthermal plasma, and NO(x) recirculation: improvement of the recirculation process.

PubMed

Yoshida, Keiichiro; Kuwahara, Takuya; Kuroki, Tomoyuki; Okubo, Masaaki

2012-09-15

NO(x) emitted from a stationary diesel engine generator was treated with a hybrid system comprising NO(x) reduction by nonthermal plasma (NTP) and temperature swing adsorption (TSA) driven by engine waste heat. TSA produces a low-volume gas mixture of N(2) and highly concentrated NO(x), which is effectively reduced by NTP treatment. Improved treatment performance and efficiency are achieved by re-injecting the NTP-treated gas mixture into the engine intake. The system comprises two switchable adsorption chambers; the operation of this system was simulated by using a one-chamber system. The maximum energy efficiency for NO(x) treatment is 200 g(NO(2))/kWh. The respective contributions of NTP and injection of N(2) and NO(x) to the performance were theoretically analyzed. The analysis predicts that high energy efficiency and high NO(x)-removal efficiency can be simultaneously achieved with this system but miniaturization of the adsorption chambers will be a challenge. Copyright © 2012 Elsevier B.V. All rights reserved.

Stratified charge rotary engine combustion studies

NASA Technical Reports Server (NTRS)

Shock, H.; Hamady, F.; Somerton, C.; Stuecken, T.; Chouinard, E.; Rachal, T.; Kosterman, J.; Lambeth, M.; Olbrich, C.

1989-01-01

Analytical and experimental studies of the combustion process in a stratified charge rotary engine (SCRE) continue to be the subject of active research in recent years. Specifically to meet the demand for more sophisticated products, a detailed understanding of the engine system of interest is warranted. With this in mind the objective of this work is to develop an understanding of the controlling factors that affect the SCRE combustion process so that an efficient power dense rotary engine can be designed. The influence of the induction-exhaust systems and the rotor geometry are believed to have a significant effect on combustion chamber flow characteristics. In this report, emphasis is centered on Laser Doppler Velocimetry (LDV) measurements and on qualitative flow visualizations in the combustion chamber of the motored rotary engine assembly. This will provide a basic understanding of the flow process in the RCE and serve as a data base for verification of numerical simulations. Understanding fuel injection provisions is also important to the successful operation of the stratified charge rotary engine. Toward this end, flow visualizations depicting the development of high speed, high pressure fuel jets are described. Friction is an important consideration in an engine from the standpoint of lost work, durability and reliability. MSU Engine Research Laboratory efforts in accessing the frictional losses associated with the rotary engine are described. This includes work which describes losses in bearing, seal and auxillary components. Finally, a computer controlled mapping system under development is described. This system can be used to map shapes such as combustion chamber, intake manifolds or turbine blades accurately.

Stratified charge rotary engine combustion studies

NASA Astrophysics Data System (ADS)

Shock, H.; Hamady, F.; Somerton, C.; Stuecken, T.; Chouinard, E.; Rachal, T.; Kosterman, J.; Lambeth, M.; Olbrich, C.

1989-07-01

Analytical and experimental studies of the combustion process in a stratified charge rotary engine (SCRE) continue to be the subject of active research in recent years. Specifically to meet the demand for more sophisticated products, a detailed understanding of the engine system of interest is warranted. With this in mind the objective of this work is to develop an understanding of the controlling factors that affect the SCRE combustion process so that an efficient power dense rotary engine can be designed. The influence of the induction-exhaust systems and the rotor geometry are believed to have a significant effect on combustion chamber flow characteristics. In this report, emphasis is centered on Laser Doppler Velocimetry (LDV) measurements and on qualitative flow visualizations in the combustion chamber of the motored rotary engine assembly. This will provide a basic understanding of the flow process in the RCE and serve as a data base for verification of numerical simulations. Understanding fuel injection provisions is also important to the successful operation of the stratified charge rotary engine. Toward this end, flow visualizations depicting the development of high speed, high pressure fuel jets are described. Friction is an important consideration in an engine from the standpoint of lost work, durability and reliability. MSU Engine Research Laboratory efforts in accessing the frictional losses associated with the rotary engine are described. This includes work which describes losses in bearing, seal and auxillary components. Finally, a computer controlled mapping system under development is described. This system can be used to map shapes such as combustion chamber, intake manifolds or turbine blades accurately.

A theoretical model of fuselage pressure levels due to fan tones radiated from the intake of an installed turbofan aero-engine.

PubMed

Gaffney, James; McAlpine, Alan; Kingan, Michael J

2018-06-01

An existing theoretical model to predict the pressure levels on an aircraft's fuselage is improved by incorporating a more physically realistic method to predict fan tone radiation from the intake of an installed turbofan aero-engine. Such a model can be used as part of a method to assess cabin noise. Fan tone radiation from a turbofan intake is modelled using the exact solution for the radiated pressure from a spinning mode exiting a semi-infinite cylindrical duct immersed in a uniform flow. This approach for a spinning duct mode incorporates scattering/diffraction by the intake lip, enabling predictions of the radiated pressure valid in both the forward and aft directions. The aircraft's fuselage is represented by an infinitely long, rigid cylinder. There is uniform flow aligned with the cylinder, except close to the cylinder's surface where there is a constant-thickness boundary layer. In addition to single mode calculations it is shown how the model may be used to rapidly calculate a multi-mode incoherent radiation from the engine intake. Illustrative results are presented which demonstrate the relative importance of boundary-layer shielding both upstream and downstream of the source, as well as examples of the fuselage pressure levels due to a multi-mode tonal source at high Helmholtz number.

Design and Performance of LPG Fuel Mixer for Dual Fuel Diesel Engine

NASA Astrophysics Data System (ADS)

Desrial; Saputro, W.; Garcia, P. P.

2018-05-01

Small horizontal diesel engines are commonly used for agricultural machinery, however, availability of diesel fuel become one of big problems especially in remote area. Conversely, in line with government policy for conversion of kerosene into LPG for cooking, then LPG become more popular and available even in remote area. Therefore, LPG is potential fuel to replace the shortage of diesel fuel for operating diesel engine in remote area. The purpose of this study was to design mixing device for using dual fuel i.e. LPG and diesel fuel and evaluate its performance accordingly. Simulation by using CFD was done in order to analyze mixture characteristics of LPG in air intake manifold. The performance test was done by varying the amount of LPG injected in intake air at 20%, 25%, 30%, 35%, until 40%, respectively. Result of CFD contour simulation showed the best combination when mixing 30% LPG into the intake air. Performance test of this research revealed that mixing LPG in air intake can reduce the diesel fuel consumption about 0.7 l/hour (without load) and 1.14 l/hour (with load). Diesel engine revolution increases almost 300 rpm faster than when using diesel fuel only. Based on economic analysis, using the fuel combination (diesel fuel – LPG) is not recommended in the area near SPBU where the price of diesel fuel is standard. However, using the fuel combination LPG-diesel fuel is highly recommended in the remote areas in Indonesia where price of diesel fuel is comparatively expensive which will provide cheaper total fuel cost for diesel engine operation.

Mid-IR fiber optic sensors for internal combustion engines

NASA Astrophysics Data System (ADS)

Hall, Matthew J.

1999-12-01

Environmental regulations are driving development of cleaner spark ignition, diesel, and gas turbine engines. Emissions of unburned hydrocarbons, NOx, and CO can be affected by the characteristics of the mixing of the fuel with air in the engine, and by the amount of exhaust gas recirculated to the engine intake. Fiber optic sensors have been developed that can measure the local fuel concentration in the combustion chamber of a spark ignition engine near the spark plug. The sensors detect the absorption of 3.4 micrometer radiation corresponding to the strongest absorption band common to all hydrocarbons. The sensors have been applied to both liquid and gaseous hydrocarbon fuels, and liquid fuels injected directly into the engine combustion chamber. The sensors use white light sources and are designed to detect the absorption throughout the entire band minimizing calibration problems associated with pressure and temperature broadening. Other sensors can detect the concentration of CO2 in the engine intake manifold providing time-resolved measurement of exhaust gas recirculation (EGR). Proper EGR levels are critical for achieving low engine-out emissions of NOx while maintaining acceptable engine performance.

Load compensation in a lean burn natural gas vehicle

NASA Astrophysics Data System (ADS)

Gangopadhyay, Anupam

A new multivariable PI tuning technique is developed in this research that is primarily developed for regulation purposes. Design guidelines are developed based on closed-loop stability. The new multivariable design is applied in a natural gas vehicle to combine idle and A/F ratio control loops. This results in better recovery during low idle operation of a vehicle under external step torques. A powertrain model of a natural gas engine is developed and validated for steady-state and transient operation. The nonlinear model has three states: engine speed, intake manifold pressure and fuel fraction in the intake manifold. The model includes the effect of fuel partial pressure in the intake manifold filling and emptying dynamics. Due to the inclusion of fuel fraction as a state, fuel flow rate into the cylinders is also accurately modeled. A linear system identification is performed on the nonlinear model. The linear model structure is predicted analytically from the nonlinear model and the coefficients of the predicted transfer function are shown to be functions of key physical parameters in the plant. Simulations of linear system and model parameter identification is shown to converge to the predicted values of the model coefficients. The multivariable controller developed in this research could be designed in an algebraic fashion once the plant model is known. It is thus possible to implement the multivariable PI design in an adaptive fashion combining the controller with identified plant model on-line. This will result in a self-tuning regulator (STR) type controller where the underlying design criteria is the multivariable tuning technique designed in this research.

PIV measurements of in-cylinder, large-scale structures in a water-analogue Diesel engine

NASA Astrophysics Data System (ADS)

Kalpakli Vester, A.; Nishio, Y.; Alfredsson, P. H.

2016-11-01

Swirl and tumble are large-scale structures that develop in an engine cylinder during the intake stroke. Their structure and strength depend on the design of the inlet ports and valves, but also on the valve lift history. Engine manufacturers make their design to obtain a specific flow structure that is assumed to give the best engine performance. Despite many efforts, there are still open questions, such as how swirl and tumble depend on the dynamics of the valves/piston as well as how cycle-to-cycle variations should be minimized. In collaboration with Swedish vehicle industry we perform PIV measurements of the flow dynamics during the intake stroke inside a cylinder of a water-analogue engine model having the same geometrical characteristics as a typical truck Diesel engine. Water can be used since during the intake stroke the flow is nearly incompressible. The flow from the valves moves radially outwards, hits the vertical walls of the cylinder, entrains surrounding fluid, moves along the cylinder walls and creates a central backflow, i.e. a tumble motion. Depending on the port and valve design and orientation none, low, or high swirl can be established. For the first time, the effect of the dynamic motion of the piston/valves on the large-scale structures is captured. Supported by the Swedish Energy Agency, Scania CV AB and Volvo GTT, through the FFI program.

Assessment of the effect of gaseous fuel delivery mode on thermal efficiency and fuel losses during the valve overlap period in a dual-fuel compression ignition engine

NASA Astrophysics Data System (ADS)

Skrzek, T.

2016-09-01

The paper describes the effect of dual fuelling of single cylinder AVL test CI engine with the use of two ways of gas delivery to the engine manifold. The engine was fuelled diesel oil and propane. For all the tests, gas consumption was maintained at the same level. In the first mode the gas was delivered by injector located under inlet valve. In the second method, there was used a mixer fitted to the intake manifold. The paper compares the results of thermal efficiency and emissions of propane in the exhaust for both fuelling modes. Research clearly show how important it is to synchronize the injector opening time of the intake stroke. This is especially important for supercharged engines in which there is a valve overlap.

Selective NOx Recirculation for Stationary Lean-Burn Natural Gas Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nigel Clark; Gregory Thompson; Richard Atkinson

Selective NOx Recirculation (SNR) involves cooling the engine exhaust gas and then adsorbing the oxides of nitrogen (NOx) from the exhaust stream, followed by the periodic desorption of NOx. By returning the desorbed, concentrated NOx into the engine intake and through the combustion chamber, a percentage of the NOx is decomposed during the combustion process. An initial study of NOx decomposition during lean-burn combustion was concluded in 2004 using a 1993 Cummins L10G 240hp natural gas engine. It was observed that the air/fuel ratio, injected NO (nitric oxide) quantity and engine operating points affected NOx decomposition rates of the engine.more » Chemical kinetic modeling results were also used to determine optimum NOx decomposition operating points and were published in the 2004 annual report. A NOx decomposition rate of 27% was measured from this engine under lean-burn conditions while the software model predicted between 35-42% NOx decomposition for similar conditions. A later technology 1998 Cummins L10G 280hp natural gas engine was procured with the assistance of Cummins Inc. to replace the previous engine used for 2005 experimental research. The new engine was equipped with an electronic fuel management system with closed-loop control that provided a more stable air/fuel ratio control and improved the repeatability of the tests. The engine was instrumented with an in-cylinder pressure measurement system and electronic controls, and was adapted to operate over a range of air/fuel ratios. The engine was connected to a newly commissioned 300hp alternating current (AC) motoring dynamometer. The second experimental campaign was performed to acquire both stoichiometric and slightly rich (0.97 lambda ratio) burn NOx decomposition rates. Effects of engine load and speed on decomposition were quantified, but Exhaust Gas Recirculation (EGR) was not varied independently. Decomposition rates of up to 92% were demonstrated. Following recommendations at the 2004 ARES peer review meeting at Argonne National Laboratories, in-cylinder pressure was measured to calculate engine indicated mean effective pressure (IMEP) changes due to NOx injections and EGR variations, and to observe conditions in the cylinder. The third experimental campaign gathered NOx decomposition data at 800, 1200 and 1800 rpm. EGR was added via an external loop, with EGR ranging from zero to the point of misfire. The air/fuel ratio was set at both stoichiometric and slightly rich conditions, and NOx decomposition rates were calculated for each set of runs. Modifications were made to the engine exhaust manifold to record individual exhaust temperatures. The three experimental campaigns have provided the data needed for a comprehensive model of NOx decomposition during the combustion process, and data have confirmed that there was no significant impact of injected NO on in-cylinder pressure. The NOx adsorption system provided by Sorbent Technologies Corp. (Twinsburg, OH), comprised a NOx adsorber, heat exchanger and a demister. These components were connected to the engine, and data were gathered to show both the adsorption of NOx from the engine, and desorption of NOx from the carbon-based sorbent material back into the engine intake, using a heated air stream. In order to quantify the NOx adsorption/desorption characteristics of the sorbent material, a bench top adsorption system was constructed and instrumented with thermocouples and the system output was fed into a NOx analyzer. The temperature of this apparatus was controlled while gathering data on the characteristics of the sorbent material. These data were required for development of a system model. Preliminary data were gathered in 2005, and will continue in early 2006. To assess the economic benefits of the proposed SNR technology the WVU research team has been joined in the last quarter by Dr Richard Turton (WVU-Chemical Engineering), who is modeling, sizing and costing the major components. The tasks will address modeling and preliminary design of the heat exchanger, demister and NOx sorbent chamber suitable for a given engine. A simplified linear driving force model was developed to predict NOx adsorption into the sorbent material as cooled exhaust passes over fresh sorbent material. This aspect of the research will continue into 2006, and the benefits and challenges of SNR will be compared with those of competing systems, such as Selective Catalytic Reduction. Chemical kinetic modeling using the CHEMKIN software package was extended in 2005 to the case of slightly rich burn with EGR. Simulations were performed at 10%, 20%, 30% and 40% of the intake air replaced with EGR. NOx decomposition efficiency was calculated at the point in time where 98% of fuel was consumed, which is believed to be a conservative approach. The modeling data show that reductions of over 70% are possible using the ''98% fuel burned'' assumption.« less

40 CFR 86.311-79 - Miscellaneous equipment; specifications.

Code of Federal Regulations, 2011 CFR

2011-07-01

... engines. (2) When testing gasoline-fueled engines all chart recorders (analyzers, torque, rpm, etc.) shall.... (b) Accuracy of temperature measurements. (1) The following temperature measurements shall be accurate to within 1.2 °C: (i) Temperature measurements used in calculating the engine intake humidity: (ii...

40 CFR 86.311-79 - Miscellaneous equipment; specifications.

Code of Federal Regulations, 2012 CFR

2012-07-01

... engines. (2) When testing gasoline-fueled engines all chart recorders (analyzers, torque, rpm, etc.) shall.... (b) Accuracy of temperature measurements. (1) The following temperature measurements shall be accurate to within 1.2 °C: (i) Temperature measurements used in calculating the engine intake humidity: (ii...

40 CFR 86.311-79 - Miscellaneous equipment; specifications.

Code of Federal Regulations, 2013 CFR

2013-07-01

... engines. (2) When testing gasoline-fueled engines all chart recorders (analyzers, torque, rpm, etc.) shall.... (b) Accuracy of temperature measurements. (1) The following temperature measurements shall be accurate to within 1.2 °C: (i) Temperature measurements used in calculating the engine intake humidity: (ii...

On the thermodynamics of waste heat recovery from internal combustion engine exhaust gas

NASA Astrophysics Data System (ADS)

Meisner, G. P.

2013-03-01

The ideal internal combustion (IC) engine (Otto Cycle) efficiency ηIC = 1-(1/r)(γ - 1) is only a function of engine compression ratio r =Vmax/Vmin and exhaust gas specific heat ratio γ = cP/cV. Typically r = 8, γ = 1.4, and ηIC = 56%. Unlike the Carnot Cycle where ηCarnot = 1-(TC/TH) for a heat engine operating between hot and cold heat reservoirs at TH and TC, respectively, ηIC is not a function of the exhaust gas temperature. Instead, the exhaust gas temperature depends only on the intake gas temperature (ambient), r, γ, cV, and the combustion energy. The ejected exhaust gas heat is thermally decoupled from the IC engine and conveyed via the exhaust system (manifold, pipe, muffler, etc.) to ambient, and the exhaust system is simply a heat engine that does no useful work. The maximum fraction of fuel energy that can be extracted from the exhaust gas stream as useful work is (1-ηIC) × ηCarnot = 32% for TH = 850 K (exhaust) and TC = 370 K (coolant). This waste heat can be recovered using a heat engine such as a thermoelectric generator (TEG) with ηTEG> 0 in the exhaust system. A combined IC engine and TEG system can generate net useful work from the exhaust gas waste heat with efficiency ηWH = (1-ηIC) × ηCarnot ×ηTEG , and this will increase the overall fuel efficiency of the total system. Recent improvements in TEGs yield ηTEG values approaching 15% giving a potential total waste heat conversion efficiency of ηWH = 4.6%, which translates into a fuel economy improvement approaching 5%. This work is supported by the US DOE under DE-EE0005432.

40 CFR 94.204 - Designation of engine families.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Combustion chamber design; (6) Bore; (7) Stroke; (8) Number of cylinders, (engines with aftertreatment... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5...

40 CFR 94.204 - Designation of engine families.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Combustion chamber design; (6) Bore; (7) Stroke; (8) Number of cylinders, (engines with aftertreatment... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5...

40 CFR 94.204 - Designation of engine families.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Combustion chamber design; (6) Bore; (7) Stroke; (8) Number of cylinders, (engines with aftertreatment... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5...

40 CFR 94.204 - Designation of engine families.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Combustion chamber design; (6) Bore; (7) Stroke; (8) Number of cylinders, (engines with aftertreatment... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5...

40 CFR 94.204 - Designation of engine families.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Combustion chamber design; (6) Bore; (7) Stroke; (8) Number of cylinders, (engines with aftertreatment... stroke dimensions; (4) The approximate intake and exhaust event timing and duration (valve or port); (5...

Flight-determined characteristics of an air intake system on an F-111A airplane

NASA Technical Reports Server (NTRS)

Hughes, D. L.; Johnson, H. J.

1972-01-01

Flow phenomena of the F-111A air intake system were investigated over a large range of Mach number, altitude, and angle of attack. Boundary-layer variations are shown for the fuselage splitter plate and inlet entrance stations. Inlet performance is shown in terms of pressure recovery, airflow, mass-flow ratio, turbulence factor, distortion factor, and power spectral density. The fuselage boundary layer was found to be not completely removed from the upper portion of the splitter plate at all Mach numbers investigated. Inlet boundary-layer ingestion started at approximately Mach 1.6 near the translating spike and cone. Pressure-recovery distribution at the compressor face showed increasing distortion with increasing angle of attack and increasing Mach number. The time-averaged distortion-factor value approached 1300, which is near the distortion tolerance of the engine at Mach numbers above 2.1.

Slide valve apparatus for internal combustion engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, B.A.; McMahan, T.O.

This patent describes an internal combustion engine including a combustion cylinder having an opening at one end thereof, a piston mounted within the cylinder for coaxial reciprocable movement, a driven crankshaft, and a connecting rod connecting the crankshaft to the cylinder for linear reciprocable movement of the piston in response to the rotary movement of the crankshaft, a valve apparatus comprising: (a) a valve chamber extending longitudinally across and in fluid communication with the opening in the cylinder, (b) an intake valve plate having a longitudinal axis mounted within the valve chamber for slidable, reciprocable, longitudinal movement, (c) an exhaustmore » valve plate having a longitudinal axis mounted within the valve chamber alongside the intake valve plate for slidable, reciprocable, longitudinal movement and parallel to the longitudinal axis of the intake valve plate, (d) each of the valve plates having a plurality of longitudinally spaced valve ports therein, the valve ports comprising movable intake valve ports in the intake valve plate and movable exhaust valve ports in the exhaust valve plate, (e) the valve chamber comprising a planar wall on the opposite side of the valve plates from the cylinder opening and having a plurality of fixed valve ports therethrough. The fixed valve ports being equal in number and substantially equal in size and spacing as the movable intake and exhaust valve ports, whereby the movable intake valve ports are adapted to register with their corresponding fixed valve ports when the intake valve plate is in its intake operative position for opening fluid communication between the cylinder and the corresponding fixed valve ports.« less

Intake and urinary excretion of sodium chloride under varying conditions of effort and environment heat

NASA Technical Reports Server (NTRS)

Zohar, E.; Adar, R.; Tennenbaum, J.; Kesten, M.

1982-01-01

Intake and urinary excretion of sodium were investigated in a group of young, healthy and acclimated men. The sodium excretions of workers and of machinists in the engine rooms of a ship were also investigated.

Assessment of total efficiency in adiabatic engines

NASA Astrophysics Data System (ADS)

Mitianiec, W.

2016-09-01

The paper presents influence of ceramic coating in all surfaces of the combustion chamber of SI four-stroke engine on working parameters mainly on heat balance and total efficiency. Three cases of engine were considered: standard without ceramic coating, fully adiabatic combustion chamber and engine with different thickness of ceramic coating. Consideration of adiabatic or semi-adiabatic engine was connected with mathematical modelling of heat transfer from the cylinder gas to the cooling medium. This model takes into account changeable convection coefficient based on the experimental formulas of Woschni, heat conductivity of multi-layer walls and also small effect of radiation in SI engines. The simulation model was elaborated with full heat transfer to the cooling medium and unsteady gas flow in the engine intake and exhaust systems. The computer program taking into account 0D model of engine processes in the cylinder and 1D model of gas flow was elaborated for determination of many basic engine thermodynamic parameters for Suzuki DR-Z400S 400 cc SI engine. The paper presents calculation results of influence of the ceramic coating thickness on indicated pressure, specific fuel consumption, cooling and exhaust heat losses. Next it were presented comparisons of effective power, heat losses in the cooling and exhaust systems, total efficiency in function of engine rotational speed and also comparison of temperature inside the cylinder for standard, semi-adiabatic and full adiabatic engine. On the basis of the achieved results it was found higher total efficiency of adiabatic engines at 2500 rpm from 27% for standard engine to 37% for full adiabatic engine.

Quantitative measurements of in-cylinder gas composition in a controlled auto-ignition combustion engine

NASA Astrophysics Data System (ADS)

Zhao, H.; Zhang, S.

2008-01-01

One of the most effective means to achieve controlled auto-ignition (CAI) combustion in a gasoline engine is by the residual gas trapping method. The amount of residual gas and mixture composition have significant effects on the subsequent combustion process and engine emissions. In order to obtain quantitative measurements of in-cylinder residual gas concentration and air/fuel ratio, a spontaneous Raman scattering (SRS) system has been developed recently. The optimized optical SRS setups are presented and discussed. The temperature effect on the SRS measurement is considered and a method has been developed to correct for the overestimated values due to the temperature effect. Simultaneous measurements of O2, H2O, CO2 and fuel were obtained throughout the intake, compression, combustion and expansion strokes. It shows that the SRS can provide valuable data on this process in a CAI combustion engine.

Martian Atmospheric Dust Mitigation for ISRU Intakes via Electrostatic Precipitation

NASA Technical Reports Server (NTRS)

Phillips, James R., III; Pollard, Jacob R. S.; Johansen, Michael R.; Mackey, Paul J.; Clements, Sid; Calle, Carlos I.

2016-01-01

This document is the presentation to be given at the 2016 American Society of Civil Engineers Earth and Space Conference to examine the concept of using electrostatic precipitation for Martian atmospheric dust mitigation of the intakes of in-situ resource utilization reactors.

The Elimination of Fire Hazard Due to Back Fires

NASA Technical Reports Server (NTRS)

Theodorsen, Theodore; Freeman, Ira M

1933-01-01

A critical study was made of the operation of a type of back-fire arrester used to reduce the fire hazard of aircraft engines. A flame arrester consisting of a pack or plug of alternate flat and corrugated plates of thin metal was installed in the intake pipe of a gasoline engines; an auxiliary spark plug inserted in the intake manifold permitted the production of artificial back fires at will. It was found possible to design a plug which prevented all back fires from reaching the carburetor.

Evidence Report: Risk Factor of Inadequate Nutrition

NASA Technical Reports Server (NTRS)

Smith, Scott M.; Zwart, Sara R.; Heer, Martina

2015-01-01

The importance of nutrition in exploration has been documented repeatedly throughout history, where, for example, in the period between Columbus' voyage in 1492 and the invention of the steam engine, scurvy resulted in more sailor deaths than all other causes of death combined. Because nutrients are required for the structure and function of every cell and every system in the body, defining the nutrient requirements for spaceflight and ensuring provision and intake of those nutrients are primary issues for crew health and mission success. Unique aspects of nutrition during space travel include the overarching physiological adaptation to weightlessness, psychological adaptation to extreme and remote environments, and the ability of nutrition and nutrients to serve as countermeasures to ameliorate the negative effects of spaceflight on the human body. Key areas of clinical concern for long-duration spaceflight include loss of body mass (general inadequate food intake), bone and muscle loss, cardiovascular and immune system decrements, increased radiation exposure and oxidative stress, vision and ophthalmic changes, behavior and performance, nutrient supply during extravehicular activity, and general depletion of body nutrient stores because of inadequate food supply, inadequate food intake, increased metabolism, and/or irreversible loss of nutrients. These topics are reviewed herein, based on the current gap structure.

Engine flow visualization using a copper vapor laser

NASA Technical Reports Server (NTRS)

Regan, Carolyn A.; Chun, Kue S.; Schock, Harold J., Jr.

1987-01-01

A flow visualization system has been developed to determine the air flow within the combustion chamber of a motored, axisymmetric engine. The engine has been equipped with a transparent quartz cylinder, allowing complete optical access to the chamber. A 40-Watt copper vapor laser is used as the light source. Its beam is focused down to a sheet approximately 1 mm thick. The light plane is passed through the combustion chamber, and illuminates oil particles which were entrained in the intake air. The light scattered off of the particles is recorded by a high speed rotating prism movie camera. A movie is then made showing the air flow within the combustion chamber for an entire four-stroke engine cycle. The system is synchronized so that a pulse generated by the camera triggers the laser's thyratron. The camera is run at 5,000 frames per second; the trigger drives one laser pulse per frame. This paper describes the optics used in the flow visualization system, the synchronization circuit, and presents results obtained from the movie. This is believed to be the first published study showing a planar observation of airflow in a four-stroke piston-cylinder assembly. These flow visualization results have been used to interpret flow velocity measurements previously obtained with a laser Doppler velocimetry system.

40 CFR 90.301 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the test engine is operated using a steady state test cycle on an engine dynamometer. The exhaust... concentrations are converted to mass emission rates in grams per hour based on either fuel flow, fuel flow and engine intake air flow, or exhaust volume flow. Weighted emission rates are reported as grams per brake...

British government, industry agree to fund Hotel launcher studies

NASA Astrophysics Data System (ADS)

Brown, D. A.

1986-02-01

A program status assessment is presented for the horizontal takeoff and landing 'Hotol' single-stage-to-orbit space launcher, for which parallel, two-year airframe and propulsion system proof-of-concept studies have been approved. A two-year initial development program for the airframe would be followed by a four-year development and manufacturing phase that would begin upon the propulsion system concept's successful demonstration. Flight trials could begin in 1996. A number of significant modifications have already been made to the initial design concept, such as to the foreplanes, afterbody, engine intake, and orbital control system.

Numerical simulation of helicopter engine plume in forward flight

NASA Technical Reports Server (NTRS)

Dimanlig, Arsenio C. B.; Vandam, Cornelis P.; Duque, Earl P. N.

1994-01-01

Flowfields around helicopters contain complex flow features such as large separated flow regions, vortices, shear layers, blown and suction surfaces and an inherently unsteady flow imposed by the rotor system. Another complicated feature of helicopters is their infrared signature. Typically, the aircraft's exhaust plume interacts with the rotor downwash, the fuselage's complicated flowfield, and the fuselage itself giving each aircraft a unique IR signature at given flight conditions. The goal of this project was to compute the flow about a realistic helicopter fuselage including the interaction of the engine air intakes and exhaust plume. The computations solve the Think-Layer Navier Stokes equations using overset type grids and in particular use the OVERFLOW code by Buning of NASA Ames. During this three month effort, an existing grid system of the Comanche Helicopter was to be modified to include the engine inlet and the hot engine exhaust. The engine exhaust was to be modeled as hot air exhaust. However, considerable changes in the fuselage geometry required a complete regriding of the surface and volume grids. The engine plume computations have been delayed to future efforts. The results of the current work consists of a complete regeneration of the surface and volume grids of the most recent Comanche fuselage along with a flowfield computation.

Improvement of the thermal and mechanical flow characteristics in the exhaust system of piston engine through the use of ejection effect

NASA Astrophysics Data System (ADS)

Plotnikov, L. V.; Zhilkin, B. P.; Brodov, Yu M.

2017-11-01

The results of experimental research of gas dynamics and heat transfer in the exhaust process in piston internal combustion engines are presented. Studies were conducted on full-scale models of piston engine in the conditions of unsteady gas-dynamic (pulsating flows). Dependences of the instantaneous flow speed and the local heat transfer coefficient from the crankshaft rotation angle in the exhaust pipe are presented in the article. Also, the flow characteristics of the exhaust gases through the exhaust systems of various configurations are analyzed. It is shown that installation of the ejector in the exhaust system lead to a stabilization of the flow and allows to improve cleaning of the cylinder from exhaust gases and to optimize the thermal state of the exhaust pipes. Experimental studies were complemented by numerical simulation of the working process of the DM-21 diesel engine (production of “Ural diesel-motor plant”). The object of modeling was the eight-cylinder diesel with turbocharger. The simulation was performed taking into account the processes nonstationarity in the intake and exhaust pipes for the various configurations of exhaust systems (with and without ejector). Numerical simulation of the working process of diesel was performed in ACTUS software (ABB Turbo Systems). The simulation results confirmed the stabilization of the flow due to the use of the ejection effect in the exhaust system of a diesel engine. The use of ejection in the exhaust system of the DM-21 diesel leads to improvement of cleaning cylinders up to 10 %, reduces the specific fuel consumption on average by 1 %.

Combined rankine and vapor compression cycles

DOEpatents

Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

2005-04-19

An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

The effects of engine speed and injection characteristics on the flow field and fuel/air mixing in motored two-stroke diesel engines

NASA Technical Reports Server (NTRS)

Nguyen, H. L.; Carpenter, M. H.; Ramos, J. I.

1987-01-01

A numerical analysis is presented on the effects of the engine speed, injection angle, droplet distribution function, and spray cone angle on the flow field, spray penetration and vaporization, and turbulence in a turbocharged motored two-stroke diesel engine. The results indicate that the spray penetration and vaporization, velocity, and turbulence kinetic energy increase with the intake swirl angle. Good spray penetration, vaporization, and mixing can be achieved by injecting droplets of diameters between 50 and 100 microns along a 120-deg cone at about 315 deg before top-dead-center for an intake swirl angle of 30 deg. The spray penetration and vaporization were found to be insensitive to the turbulence levels within the cylinder. The results have also indicated that squish is necessary in order to increase the fuel vaporization rate and mixing.

A Study on Homogeneous Charge Compression Ignition Gasoline Engines

NASA Astrophysics Data System (ADS)

Kaneko, Makoto; Morikawa, Koji; Itoh, Jin; Saishu, Youhei

A new engine concept consisting of HCCI combustion for low and midrange loads and spark ignition combustion for high loads was introduced. The timing of the intake valve closing was adjusted to alter the negative valve overlap and effective compression ratio to provide suitable HCCI conditions. The effect of mixture formation on auto-ignition was also investigated using a direct injection engine. As a result, HCCI combustion was achieved with a relatively low compression ratio when the intake air was heated by internal EGR. The resulting combustion was at a high thermal efficiency, comparable to that of modern diesel engines, and produced almost no NOx emissions or smoke. The mixture stratification increased the local A/F concentration, resulting in higher reactivity. A wide range of combustible A/F ratios was used to control the compression ignition timing. Photographs showed that the flame filled the entire chamber during combustion, reducing both emissions and fuel consumption.

Fuel-air mixing and combustion in a two-dimensional Wankel engine

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Schock, H. J.; Ramos, J. I.

1987-01-01

A two-equation turbulence model, an algebraic grid generalization method, and an approximate factorization time-linearized numerical technique are used to study the effects of mixture stratification at the intake port and gaseous fuel injection on the flow field and fuel-air mixing in a two-dimensional rotary engine model. The fuel distribution in the combustion chamber is found to be a function of the air-fuel mixture fluctuations at the intake port. It is shown that the fuel is advected by the flow field induced by the rotor and is concentrated near the leading apex during the intake stroke, while during compression, the fuel concentration is highest near the trailing apex and is lowest near the rotor. It is also found that the fuel concentration near the trailing apex and rotor is small except at high injection velocities.

Single rotor turbine engine

DOEpatents

Platts, David A.

2002-01-01

There has been invented a turbine engine with a single rotor which cools the engine, functions as a radial compressor, pushes air through the engine to the ignition point, and acts as an axial turbine for powering the compressor. The invention engine is designed to use a simple scheme of conventional passage shapes to provide both a radial and axial flow pattern through the single rotor, thereby allowing the radial intake air flow to cool the turbine blades and turbine exhaust gases in an axial flow to be used for energy transfer. In an alternative embodiment, an electric generator is incorporated in the engine to specifically adapt the invention for power generation. Magnets are embedded in the exhaust face of the single rotor proximate to a ring of stationary magnetic cores with windings to provide for the generation of electricity. In this alternative embodiment, the turbine is a radial inflow turbine rather than an axial turbine as used in the first embodiment. Radial inflow passages of conventional design are interleaved with radial compressor passages to allow the intake air to cool the turbine blades.

Cylinder head for internal combustion engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, D.W.

1992-10-06

This patent describes a cylinder head for attachment to a block assembly having at least one cylinder bore therein. It comprises: a cylinder head body adapted for attachment to the block assembly and having at least one side-entry fluid intake opening in communication with the cylinder bore, and having at least one side-exit exhaust fluid opening in communication with the cylinderbore; an intake spool mounted for axial rotation within the intake spool cavity; an exhaust spool mounted for axial rotation within the exhaust spool cavity; timing means for rotating the intake spool and the exhaust spool; and at least onemore » intake port and at least one exhaust port.« less

Simulation and experiment for oxygen-enriched combustion engine using liquid oxygen to solidify CO2

NASA Astrophysics Data System (ADS)

Liu, Yongfeng; Jia, Xiaoshe; Pei, Pucheng; Lu, Yong; Yi, Li; Shi, Yan

2016-01-01

For capturing and recycling of CO2 in the internal combustion engine, Rankle cycle engine can reduce the exhaust pollutants effectively under the condition of ensuring the engine thermal efficiency by using the techniques of spraying water in the cylinder and optimizing the ignition advance angle. However, due to the water spray nozzle need to be installed on the cylinder, which increases the cylinder head design difficulty and makes the combustion conditions become more complicated. In this paper, a new method is presented to carry out the closing inlet and exhaust system for internal combustion engines. The proposed new method uses liquid oxygen to solidify part of cooled CO2 from exhaust system into dry ice and the liquid oxygen turns into gas oxygen which is sent to inlet system. The other part of CO2 is sent to inlet system and mixed with oxygen, which can reduce the oxygen-enriched combustion detonation tendency and make combustion stable. Computing grid of the IP52FMI single-cylinder four-stroke gasoline-engine is established according to the actual shape of the combustion chamber using KIVA-3V program. The effects of exhaust gas recirculation (EGR) rate are analyzed on the temperatures, the pressures and the instantaneous heat release rates when the EGR rate is more than 8%. The possibility of enclosing intake and exhaust system for engine is verified. The carbon dioxide trapping device is designed and the IP52FMI engine is transformed and the CO2 capture experiment is carried out. The experimental results show that when the EGR rate is 36% for the optimum EGR rate. When the liquid oxygen of 35.80-437.40 g is imported into the device and last 1-20 min, respectively, 21.50-701.30 g dry ice is obtained. This research proposes a new design method which can capture CO2 for vehicular internal combustion engine.

Development, modeling, simulation, and testing of a novel propane-fueled Brayton-Gluhareff cycle acoustically-pressurized ramjet engine

NASA Astrophysics Data System (ADS)

Bramlette, Richard B.

In the 1950s, Eugene Gluhareff built the first working "pressure jet" engine, a variation on the classical ramjet engine with a pressurized inlet system relying on sonic tuning which allowed operation at subsonic speeds. The engine was an unqualified success. Unfortunately, after decades of sales and research, Gluhareff passed away leaving behind no significant published studies of the engine or detailed analysis of its operation. The design was at serious risk of being lost to history. This dissertation is intended to address that risk by studying a novel subscale modification of Gluhareff's original design operating on the same principles. Included is a background of related engine and how the pressure jet is distinct. The preliminary sizing of a pressure jet using closed-form expressions is then discussed followed by a review of propane oxidation modeling, how it integrates into the Computational Fluid Dynamics (CFD) solver, and the modeling of the pressure jet engine cycle with CFD. The simulation was matched to experimental data recorded on a purpose-built test stand recording chamber pressure, exhaust speed (via a Pitot/static system), temperatures, and thrust force. The engine CFD simulation produced a wide range of qualitative results that matched the experimental data well and suggested strong recirculation flows through the engine confirming suspicions about how the engine operates. Engine operating frequency between CFD and experiment also showed good agreement and appeared to be driven by the "Kadenacy Effect." The research effort lastly opens the door for further study of the engine cycle, the use of pressurized intakes to produce static thrust in a ramjet engine, the Gluhareff pressure jet's original geometry, and a wide array of potential applications. A roadmap of further study and applications is detailed including a modeling and testing of larger engines.

Truck Noise - VI A Diesel Exhaust and Air Intake Noise

DOT National Transportation Integrated Search

1973-07-01

Exhaust and air intake noise is studied on five truck and bus diesel engines; the Detroit Diesel 6-71 and 8V-71, the Cummins NHC-250 and NTC-350 and the Mack ENDT-675. The noise source is isolated and its sound level measured at a distance of 50 feet...

Advanced Natural Gas Reciprocating Engine(s)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kwok, Doris; Boucher, Cheryl

Energy independence and fuel savings are hallmarks of the nation’s energy strategy. The advancement of natural gas reciprocating engine power generation technology is critical to the nation’s future. A new engine platform that meets the efficiency, emissions, fuel flexibility, cost and reliability/maintainability targets will enable American manufacturers to have highly competitive products that provide substantial environmental and economic benefits in the US and in international markets. Along with Cummins and Waukesha, Caterpillar participated in a multiyear cooperative agreement with the Department of Energy to create a 50% efficiency natural gas powered reciprocating engine system with a 95% reduction in NOxmore » emissions by the year 2013. This platform developed under this agreement will be a significant contributor to the US energy strategy and will enable gas engine technology to remain a highly competitive choice, meeting customer cost of electricity targets, and regulatory environmental standard. Engine development under the Advanced Reciprocating Engine System (ARES) program was divided into phases, with the ultimate goal being approached in a series of incremental steps. This incremental approach would promote the commercialization of ARES technologies as soon as they emerged from development and would provide a technical and commercial foundation of later-developing technologies. Demonstrations of the Phase I and Phase II technology were completed in 2004 and 2008, respectively. Program tasks in Phase III included component and system development and testing from 2009-2012. Two advanced ignition technology evaluations were investigated under the ARES program: laser ignition and distributed ignition (DIGN). In collaboration with Colorado State University (CSU), a laser ignition system was developed to provide ignition at lean burn and high boost conditions. Much work has been performed in Caterpillar’s DIGN program under the ARES program. This work has consisted of both modeling and single cylinder engine experiments to quantify DIGN performance. The air handling systems of natural gas engines dissipate a percentage of available energy as a result of both flow losses and turbomachinery inefficiencies. An analytical study was initiated to increase compressor efficiency by employing a 2-stage inter-cooled compressor. Caterpillar also studied a turbo-compound system that employs a power turbine to recover energy from the exhaust gases for improved engine efficiency. Several other component and system investigations were undertaken during the final phase of the program to reach the ultimate ARES goals. An intake valve actuation system was developed and tested to improve engine efficiency, durability and load acceptance. Analytical modeling and materials testing were performed to evaluate the performance of steel pistons and compacted graphite iron cylinder head. Effort was made to improve the detonation sensing system by studying and comparing the performance of different pressure sensors. To reduce unburned hydrocarbon emissions, different camshafts were designed and built to investigate the effect of exhaust valve opening timing and value overlap. 1-D & 3-D coupled simulation was used to study intake and exhaust manifold dynamics with the goal of reducing load in-balance between cylinders. Selective catalytic reduction with on-board reductant generation to reduce NOx emissions was also engine tested. An effective mean to successfully deploy ARES technologies into the energy markets is to deploy demonstration projects in the field. In 2010, NETL and Caterpillar agreed to include a new “opportunity fuel” deliverable and two field demonstrations in the ARES program. An Organic Rankine Cycle system was designed with production intent incorporating lessons learned from the Phase II demonstration. Unfortunately, business conditions caused Caterpillar to cancel this demonstration in 2011. Nonetheless, Caterpillar partnered with a local dealer to deploy an ARES class engine using syngas from a biomass gasifier as the DE-FC26-01CH11079 primary combustion fuel in Gleason, TN. Upon the successful start-up and commissioning of the demonstration unit, ownership of the system was transferred to the dealer. In order to further our understanding of syngas combustion, a fundamental combustion study on syngas combustion at high pressure and lean condition was conducted through the collaboration with University of Southern California. A Methane program was also developed to rate engine performance for various compositions of syngas using empirical data obtained at CSU. While much work remains in terms of extending and integrating these developments into commercial products, it is evident that engine manufacturers on our own or through private consortium efforts could not have overcome the financial hurdles to drive these improvements into reciprocating engine and system capabilities, helping maintain the natural gas reciprocating engine power generation technology as a strong option for electric power markets, both in the United States and worldwide.« less

Cylinder To Cylinder Balancing Using Intake Valve Actuation

DOEpatents

Duffy, Kevin P.; Kieser, Andrew J.; Kilkenny, Jonathan P.

2005-01-18

A method and apparatus for balancing a combustion phasing between a plurality of cylinders located in an engine. The method and apparatus includes a determining a combustion timing in each cylinder, establishing a baseline parameter for a desired combustion timing, and varying actuation of at least one of a plurality of intake valves, each intake valve being in fluid communication with a corresponding cylinder, such that the combustion timing in each cylinder is substantially equal to the desired combustion timing.

Propulsion System for Very High Altitude Subsonic Unmanned Aircraft

NASA Technical Reports Server (NTRS)

Bents, David J.; Mockler, Ted; Maldonado, Jaime; Harp, James L., Jr.; King, Joseph F.; Schmitz, Paul C.

1998-01-01

This paper explains why a spark ignited gasoline engine, intake pressurized with three cascaded stages of turbocharging, was selected to power NASA's contemplated next generation of high altitude atmospheric science aircraft. Beginning with the most urgent science needs (the atmospheric sampling mission) and tracing through the mission requirements which dictate the unique flight regime in which this aircraft has to operate (subsonic flight at greater then 80 kft) we briefly explore the physical problems and constraints, the available technology options and the cost drivers associated with developing a viable propulsion system for this highly specialized aircraft. The paper presents the two available options (the turbojet and the turbocharged spark ignited engine) which are discussed and compared in the context of the flight regime. We then show how the unique nature of the sampling mission, coupled with the economic considerations pursuant to aero engine development, point to the spark ignited engine as the only cost effective solution available. Surprisingly, this solution compares favorably with the turbojet in the flight regime of interest. Finally, some remarks are made about NASA's present state of development, and future plans to flight demonstrate the three stage turbocharged powerplant.

Air intakes for a probative missile of rocket ramjet

NASA Technical Reports Server (NTRS)

Laruelle, G.

1984-01-01

The methods employed to test air intakes for a supersonic guided ramjet powered missile being tested by ONERA are described. Both flight tests and wind tunnel tests were performed on instrumented rockets to verify the designs. Consideration as given to the number of intakes, with the goal of delivering the maximum pressure to the engine. The S2, S4, and S5 wind tunnels were operated at Mach nos. 1.5-3 for the tests, which were compartmentalized into fuselage-intake interaction, optimization of the intake shapes, and the intake performance. Tests were performed on the length and form of the ogive, the presence of grooves, the height of traps in the boundary layer, the types and number of intakes and the lengths and forms of diffusers. Attention was also given to the effects of sideslip, effects of the longitudinal and circumferential positions of the intakes were also examined. Near optimum performance was realized during Mach 2.2 test flights of the prototype rockets.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dempsey, Adam B.; Curran, Scott; Wagner, Robert M.

Gasoline compression ignition concepts with the majority of the fuel being introduced early in the cycle are known as partially premixed combustion (PPC). Previous research on single- and multi-cylinder engines has shown that PPC has the potential for high thermal efficiency with low NOx and soot emissions. A variety of fuel injection strategies has been proposed in the literature. These injection strategies aim to create a partially stratified charge to simultaneously reduce NOx and soot emissions while maintaining some level of control over the combustion process through the fuel delivery system. The impact of the direct injection strategy to createmore » a premixed charge of fuel and air has not previously been explored, and its impact on engine efficiency and emissions is not well understood. This paper explores the effect of sweeping the direct injected pilot timing from -91° to -324° ATDC, which is just after the exhaust valve closes for the engine used in this study. During the sweep, the pilot injection consistently contained 65% of the total fuel (based on command duration ratio), and the main injection timing was adjusted slightly to maintain combustion phasing near top dead center. A modern four cylinder, 1.9 L diesel engine with a variable geometry turbocharger, high pressure common rail injection system, wide included angle injectors, and variable swirl actuation was used in this study. The pistons were modified to an open bowl configuration suitable for highly premixed combustion modes. The stock diesel injection system was unmodified, and the gasoline fuel was doped with a lubricity additive to protect the high pressure fuel pump and the injectors. The study was conducted at a fixed speed/load condition of 2000 rpm and 4.0 bar brake mean effective pressure (BMEP). The pilot injection timing sweep was conducted at different intake manifold pressures, swirl levels, and fuel injection GTP-15-1067, Dempsey 2 pressures. The gasoline used in this study has relatively high fuel reactivity with a research octane number of 68. The results of this experimental campaign indicate that the highest brake thermal efficiency and lowest emissions are achieved simultaneously with the earliest pilot injection timings (i.e., during the intake stroke).« less

Design and CFD analysis of intake port and exhaust port for a 4 valve cylinder head engine

NASA Astrophysics Data System (ADS)

Latheesh, V. M.; Parthasarathy, P.; Baskaran, V.; Karthikeyan, S.

2018-02-01

In cylinder air motion in a compression ignition engine effects mixing of air-fuel, quality of combustion and emission produced. The primary objective is to design and analyze intake and the exhaust port for a four valve cylinder head to meet higher emission norms for a given diesel engine with two valves. In this work, an existing cylinder head designed for two valves was redesigned with 4 valves. The modern trend also confirms this approach. This is being followed in the design and development of new generation engines to meet the stringent environment norms, competition in market and demand for more fuel-efficient engines. The swirl ratio and flow coefficient were measured for different valve lifts using STAR CCM+. CFD results were validated with the two-valve cylinder experimental results. After validation, a comparison between two-valve and four-valve cylinder head was done. The conversion of two valve cylinder head to 4 valves may not support modern high swirl generating port layout and requires a trade-off between many design parameters.

Effect of Premixed Fuel Preparation for Partially Premixed Combustion with a Low Octane Gasoline on a Light-Duty Multi-Cylinder Compression Ignition Engine

DOE PAGES

Dempsey, Adam B.; Curran, Scott; Wagner, Robert M.; ...

2015-05-12

Gasoline compression ignition concepts with the majority of the fuel being introduced early in the cycle are known as partially premixed combustion (PPC). Previous research on single- and multi-cylinder engines has shown that PPC has the potential for high thermal efficiency with low NOx and soot emissions. A variety of fuel injection strategies has been proposed in the literature. These injection strategies aim to create a partially stratified charge to simultaneously reduce NOx and soot emissions while maintaining some level of control over the combustion process through the fuel delivery system. The impact of the direct injection strategy to createmore » a premixed charge of fuel and air has not previously been explored, and its impact on engine efficiency and emissions is not well understood. This paper explores the effect of sweeping the direct injected pilot timing from -91° to -324° ATDC, which is just after the exhaust valve closes for the engine used in this study. During the sweep, the pilot injection consistently contained 65% of the total fuel (based on command duration ratio), and the main injection timing was adjusted slightly to maintain combustion phasing near top dead center. A modern four cylinder, 1.9 L diesel engine with a variable geometry turbocharger, high pressure common rail injection system, wide included angle injectors, and variable swirl actuation was used in this study. The pistons were modified to an open bowl configuration suitable for highly premixed combustion modes. The stock diesel injection system was unmodified, and the gasoline fuel was doped with a lubricity additive to protect the high pressure fuel pump and the injectors. The study was conducted at a fixed speed/load condition of 2000 rpm and 4.0 bar brake mean effective pressure (BMEP). The pilot injection timing sweep was conducted at different intake manifold pressures, swirl levels, and fuel injection GTP-15-1067, Dempsey 2 pressures. The gasoline used in this study has relatively high fuel reactivity with a research octane number of 68. The results of this experimental campaign indicate that the highest brake thermal efficiency and lowest emissions are achieved simultaneously with the earliest pilot injection timings (i.e., during the intake stroke).« less

Thermal and mechanical analysis of major components for the advanced adiabatic diesel engine

NASA Technical Reports Server (NTRS)

1983-01-01

The proposed design for the light duty diesel is an in-line four cylinder spark assisted diesel engine mounted transversely in the front of the vehicle. The engine has a one piece cylinder head, with one intake valve and one exhaust valve per cylinder. A flat topped piston is used with a cylindrical combustion chamber recessed into the cylinder head directly under the exhaust valve. A single ceramic insert is cast into the cylinder head to insulate both the combustion chamber and the exhaust port. A similar ceramic insert is cast into the head to insulate the intake port. A ceramic faceplate is pressed into the combustion face of the head to insulate the face of the head from hot combustion gas. The valve seats are machined directly into the ceramic faceplate for the intake valve and into the ceramic exhaust pot insert for the exhaust valve. Additional ceramic applications in the head are the use of ceramic valve guides and ceramic insulated valves. The ceramic valve guides are press fit into the head and are used for increased wear resistance. The ceramic insulated valves are conventional valves with the valve faces plasma spray coated with ceramic for insulation.

Comparing historical and modern methods of Sea Surface Temperature measurement - Part 1: Review of methods, field comparisons and dataset adjustments

NASA Astrophysics Data System (ADS)

Matthews, J. B. R.

2012-09-01

Sea Surface Temperature (SST) measurements have been obtained from a variety of different platforms, instruments and depths over the post-industrial period. Today most measurements come from ships, moored and drifting buoys and satellites. Shipboard methods include temperature measurement of seawater sampled by bucket and in engine cooling water intakes. Engine intake temperatures are generally thought to average a few tenths of a °C warmer than simultaneous bucket temperatures. Here I review SST measurement methods, studies comparing shipboard methods by field experiment and adjustments applied to SST datasets to account for variable methods. In opposition to contemporary thinking, I find average bucket-intake temperature differences reported from field studies inconclusive. Non-zero average differences often have associated standard deviations that are several times larger than the averages themselves. Further, average differences have been found to vary widely between ships and between cruises on the same ship. The cause of non-zero average differences is typically unclear given the general absence of additional temperature observations to those from buckets and engine intakes. Shipboard measurements appear of variable quality, highly dependent upon the accuracy and precision of the thermometer used and the care of the observer where manually read. Methods are generally poorly documented, with written instructions not necessarily reflecting actual practices of merchant mariners. Measurements cannot be expected to be of high quality where obtained by untrained sailors using thermometers of low accuracy and precision.

Novel Texture-based Probabilistic Object Recognition and Tracking Techniques for Food Intake Analysis and Traffic Monitoring

DTIC Science & Technology

2015-10-02

ratio or physical layout than the training sample, or new vs old bananas . For our system, this is similar the multimodal case mentioned above; however...different modes. Foods with multiple “types” such as green, yellow, and brown bananas are seamlessly handled as well. Secondly, with hundreds or thousands...Recognition and Classification of Food Grains, Fruits and Flowers Using Machine Vision. INTERNATIONAL JOURNAL OF FOOD ENGINEERING, 5(4), 2009. [155] T. E

Exhaust-Stack Nozzle Area and Shape for Individual Cylinder Exhaust-Gas Jet-Propulsion System

DTIC Science & Technology

1943-01-01

ty and con- siderable loss in the availabfity of the energy occurs because of acoustic shock and because the kinetic energy is trans- formed into heat ...plate in the air-intake duct. A tank was installed between the engine and the oriiice plata to damp out pulsations . The fuel flow was measured by a...with a length of flexible tubing. A tap for measuring static pres- sure was locxded in the tank. Tank pressures were main- tained by operation of an

Gasdynamic modeling and parametric study of mesoscale internal combustion swing engine/generator systems

NASA Astrophysics Data System (ADS)

Gu, Yongxian

The demand of portable power generation systems for both domestic and military applications has driven the advances of mesoscale internal combustion engine systems. This dissertation was devoted to the gasdynamic modeling and parametric study of the mesoscale internal combustion swing engine/generator systems. First, the system-level thermodynamic modeling for the swing engine/generator systems has been developed. The system performance as well as the potentials of both two- and four-stroke swing engine systems has been investigated based on this model. Then through parameterc studies, the parameters that have significant impacts on the system performance have been identified, among which, the burn time and spark advance time are the critical factors related to combustion process. It is found that the shorter burn time leads to higher system efficiency and power output and the optimal spark advance time is about half of the burn time. Secondly, the turbulent combustion modeling based on levelset method (G-equation) has been implemented into the commercial software FLUENT. Thereafter, the turbulent flame propagation in a generic mesoscale combustion chamber and realistic swing engine chambers has been studied. It is found that, in mesoscale combustion engines, the burn time is dominated by the mean turbulent kinetic energy in the chamber. It is also shown that in a generic mesoscale combustion chamber, the burn time depends on the longest distance between the initial ignition kernel to its walls and by changing the ignition and injection locations, the burn time can be reduced by a factor of two. Furthermore, the studies of turbulent flame propagation in real swing engine chambers show that the combustion can be enhanced through in-chamber turbulence augmentation and with higher engine frequency, the burn time is shorter, which indicates that the in-chamber turbulence can be induced by the motion of moving components as well as the intake gas jet flow. The burn time for current two-stroke swing engine is estimated as about 2.5 ms, which can be used in the prescribed burned mass fraction profile that follows the Wiebe's function. Finally, a 2D CFD code for compressible flow has been developed to study wave interactions in the engine and header system. It is found that with realistic working conditions, for a two-stroke swing engine, certain expansion waves can be created by the exhaust gas flows and the chamber pressure can reach as low as 5 psi below one atmosphere, which helps fill fresh reactant charge. The results also show that to obtain appropriate header tuning for the current two-stroke swing engine, the length of the header neck is about 40 cm.

Continuous reduction of cyclic adsorbed and desorbed NO(x) in diesel emission using nonthermal plasma.

PubMed

Kuwahara, Takuya; Nakaguchi, Harunobu; Kuroki, Tomoyuki; Okubo, Masaaki

2016-05-05

Considering the recent stringent regulations governing diesel NO(x) emission, an aftertreatment system for the reduction of NO(x) in the exhaust gas has been proposed and studied. The proposed system is a hybrid method combining nonthermal plasma and NOx adsorbent. The system does not require precious metal catalysts or harmful chemicals such as urea and ammonia. In the present system, NO(x) in diesel emission is treated by adsorption and desorption by adsorbent as well as nonthermal plasma reduction. In addition, the remaining NO(x) in the adsorbent is desorbed again in the supplied air by residual heat. The desorbed NO(x) in air recirculates into the intake of the engine, and this process, i.e., exhaust gas components' recirculation (EGCR) achieves NO(x) reduction. Alternate utilization of two adsorption chambers in the system can achieve high-efficiency NO(x) removal continuously. An experiment with a stationary diesel engine for electric power generation demonstrates an energy efficiency of 154 g(NO2)/kWh for NO(x) removal and continuous NO(x) reduction of 70.3%. Considering the regulation against diesel emission in Japan, i.e., the new regulation to be imposed on vehicles of 3.5-7.5 ton since 2016, the present aftertreatment system fulfills the requirement with only 1.0% of engine power. Copyright © 2016. Published by Elsevier B.V.

Reinforcement-learning-based dual-control methodology for complex nonlinear discrete-time systems with application to spark engine EGR operation.

PubMed

Shih, Peter; Kaul, Brian C; Jagannathan, S; Drallmeier, James A

2008-08-01

A novel reinforcement-learning-based dual-control methodology adaptive neural network (NN) controller is developed to deliver a desired tracking performance for a class of complex feedback nonlinear discrete-time systems, which consists of a second-order nonlinear discrete-time system in nonstrict feedback form and an affine nonlinear discrete-time system, in the presence of bounded and unknown disturbances. For example, the exhaust gas recirculation (EGR) operation of a spark ignition (SI) engine is modeled by using such a complex nonlinear discrete-time system. A dual-controller approach is undertaken where primary adaptive critic NN controller is designed for the nonstrict feedback nonlinear discrete-time system whereas the secondary one for the affine nonlinear discrete-time system but the controllers together offer the desired performance. The primary adaptive critic NN controller includes an NN observer for estimating the states and output, an NN critic, and two action NNs for generating virtual control and actual control inputs for the nonstrict feedback nonlinear discrete-time system, whereas an additional critic NN and an action NN are included for the affine nonlinear discrete-time system by assuming the state availability. All NN weights adapt online towards minimization of a certain performance index, utilizing gradient-descent-based rule. Using Lyapunov theory, the uniformly ultimate boundedness (UUB) of the closed-loop tracking error, weight estimates, and observer estimates are shown. The adaptive critic NN controller performance is evaluated on an SI engine operating with high EGR levels where the controller objective is to reduce cyclic dispersion in heat release while minimizing fuel intake. Simulation and experimental results indicate that engine out emissions drop significantly at 20% EGR due to reduction in dispersion in heat release thus verifying the dual-control approach.

Two-stroke engine diagnostics and design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-01-01

This paper focuses on research and development efforts on two-stroke cycle engines for automotive applications. Partial contents include: Velocity Field Characteristics in Motored Two-Stroke Ported Engines; Flow Vector Measurements at the Scavenging Ports in a Fired Two-Stroke Engine; A Study on Exhaust Dynamic Effect of Two-Stroke Motorcycle Petrol Engine; Characterization of Ignition and Parametric Study of a Two-Stroke-Cycle Direct-Injected Gasoline Engine; LDV Measurements of Intake Port Flow in a Two-Stroke Engine with and without Combustion; Appraisal of Regenerative Blowers for Scavenging of Small 2T S.I. Powerplants; and Development Experience of a Poppet-Valved Two-Stroke Flagship Engine.

Ceramic port shields cast in an iron engine head

NASA Technical Reports Server (NTRS)

Hakim, Nabil S.; Groeneweg, Mark A.

1989-01-01

Silicon nitride exhaust and intake port shields have been successfully cast into a gray iron cylinder head of a heavy duty diesel single cylinder research engine. Careful design considerations, finite element, and probability of survival analyses indicated viability of the design. Foundry experience, NDE, and failure investigations are reported.

40 CFR 1065.659 - Removed water correction.

Code of Federal Regulations, 2011 CFR

2011-07-01

... know that saturated water vapor conditions exist. Use good engineering judgment to measure the... absolute pressure based on an alarm set point, a pressure regulator set point, or good engineering judgment... from raw exhaust, you may determine the amount of water based on intake-air humidity, plus a chemical...

40 CFR 1065.659 - Removed water correction.

Code of Federal Regulations, 2010 CFR

2010-07-01

... know that saturated water vapor conditions exist. Use good engineering judgment to measure the... absolute pressure based on an alarm set point, a pressure regulator set point, or good engineering judgment... from raw exhaust, you may determine the amount of water based on intake-air humidity, plus a chemical...

40 CFR 92.105 - General equipment specifications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... measurements. Instruments used to measure engine power output shall comply with the requirements of § 92.106... they produce a permanent visual data record of a quality equal to or better than those required by this... calculating the engine intake humidity; (ii) The temperature of the fuel, in volume measuring flow rate...

Hydraulic design of a re-circulating water cooling system of a combined cycle power plant in Thailand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sarkar, C.K.; Pandit, D.R.; Kwon, S.G.

The paper describes the hydraulic design and hydraulic transient analysis of the re-circulating water cooling system of the combined cyclo Sipco power cogeneration plant in Thailand. The power plant of 450 MW total capacity is proposed to be built in two stages. Stage one will produce 300 MW of power and will consist of two gas turbine generators (GTG) and one steam turbine generator (STG). Stage two will produce 150 MW of power and will consist of one GTG and one STG. The cooling system will consist of one GTG and one STG. The cooling system will consist of coolingmore » towers, a combined collecting basin and pump intake sump, pumps and motors, and separate conveyance systems and condensers for the generator units in the two stages. In a re-circulating water cooling system, cold water is pumped from the pump intake sump to the condensers through the conveyance system and hot water from the condensers is carried through the returning pipeline system to the cooling towers, whence the water after cooling is drained into the sump at the base of the towers. Total cooling water requirement for the system in stage one is estimated to be 112,000 gallons per minute (GPM), and that in stage two, 56,000 GPM. The sump is designed using the computer program HEC-2, developed by the US Army Corps of Engineers (COE) and the pump intake basin, following the recommendations of the Hydraulic Institute. The pumps were sized by computing the head loss in the system, and, the steady state and transient performances (during pump start-up and shut-down procedures and due to possible power or mechanical failure of one or all pumps) of the system were analyzed by mathematically modeling the system using the computer program WHAMO (Water Hammer nd Mass Oscillations), also developed by the COE.« less

Variable Valve Actuation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jeffrey Gutterman; A. J. Lasley

2008-08-31

Many approaches exist to enable advanced mode, low temperature combustion systems for diesel engines - such as premixed charge compression ignition (PCCI), Homogeneous Charge Compression Ignition (HCCI) or other HCCI-like combustion modes. The fuel properties and the quantity, distribution and temperature profile of air, fuel and residual fraction in the cylinder can have a marked effect on the heat release rate and combustion phasing. Figure 1 shows that a systems approach is required for HCCI-like combustion. While the exact requirements remain unclear (and will vary depending on fuel, engine size and application), some form of substantially variable valve actuation ismore » a likely element in such a system. Variable valve actuation, for both intake and exhaust valve events, is a potent tool for controlling the parameters that are critical to HCCI-like combustion and expanding its operational range. Additionally, VVA can be used to optimize the combustion process as well as exhaust temperatures and impact the after treatment system requirements and its associated cost. Delphi Corporation has major manufacturing and product development and applied R&D expertise in the valve train area. Historical R&D experience includes the development of fully variable electro-hydraulic valve train on research engines as well as several generations of mechanical VVA for gasoline systems. This experience has enabled us to evaluate various implementations and determine the strengths and weaknesses of each. While a fully variable electro-hydraulic valve train system might be the 'ideal' solution technically for maximum flexibility in the timing and control of the valve events, its complexity, associated costs, and high power consumption make its implementation on low cost high volume applications unlikely. Conversely, a simple mechanical system might be a low cost solution but not deliver the flexibility required for HCCI operation. After modeling more than 200 variations of the mechanism it was determined that the single cam design did not have enough flexibility to satisfy three critical OEM requirements simultaneously, (maximum valve lift variation, intake valve opening timing and valve closing duration), and a new approach would be necessary. After numerous internal design reviews including several with the OEM a dual cam design was developed that had the flexibility to meet all motion requirements. The second cam added complexity to the mechanism however the cost was offset by the deletion of the electric motor required in the previous design. New patent applications including detailed drawings and potential valve motion profiles were generated and alternate two cam designs were proposed and evaluated for function, cost, reliability and durability. Hardware was designed and built and testing of sample hardware was successfully completed on an engine test stand. The mechanism developed during the course of this investigation can be applied by Original Equipment Manufacturers, (OEM), to their advanced diesel engines with the ultimate goal of reducing emissions and improving fuel economy. The objectives are: (1) Develop an optimal, cost effective, variable valve actuation (VVA) system for advanced low temperature diesel combustion processes. (2) Design and model alternative mechanical approaches and down-select for optimum design. (3) Build and demonstrate a mechanism capable of application on running engines.« less

Development of Intake Swirl Generators for Turbo Jet Engine Testing

DTIC Science & Technology

1987-03-01

As a test object a Larxac 04 turbofan engine was chosen which is used as propulsion in the Alpha Jet aircraft . This twospool engine features a two...a__ OPI: !’fIC-TID N .18.1 DEVELOPMENT OF NAR 8WZRL GENERATORS FOR TURBO JET ENGINE TU TING by H.P. Gensmlor*, W. Meyer**, L. Fottner*** Dipl.-Ing...at the Universitit der Bundeswehr MUnchen. The test facility is designed for turbo jet engines up to an maximum thrust of 30kN and a maximum mass

Two stroke homogenous charge compression ignition engine with pulsed air supplier

DOEpatents

Clarke, John M.

2003-08-05

A two stroke homogenous charge compression ignition engine includes a volume pulsed air supplier, such as a piston driven pump, for efficient scavenging. The usage of a homogenous charge tends to decrease emissions. The use of a volume pulsed air supplier in conjunction with conventional poppet type intake and exhaust valves results in a relatively efficient scavenging mode for the engine. The engine preferably includes features that permit valving event timing, air pulse event timing and injection event timing to be varied relative to engine crankshaft angle. The principle use of the invention lies in improving diesel engines.

Evaluation of dissociated and steam-reformed methanol as automotive engine fuels

NASA Technical Reports Server (NTRS)

Lalk, T. R.; Mccall, D. M.; Mccanlies, J. M.

1984-01-01

Dissociated and steam reformed methanol were evaluated as automotive engine fuels. Advantages and disadvantages in using methanol in the reformed rather than liquid state were discussed. Engine dynamometer tests were conducted with a four cylinder, 2.3 liter, spark ignition automotive engine to determine performance and emission characteristics operating on simulated dissociated and steam reformed methanol (2H2 + CO and 3H2 + CO2 respectively), and liquid methanol. Results are presented for engine performance and emissions as functions of equivalence ratio, at various throttle settings and engine speeds. Operation on dissociated and steam reformed methanol was characterized by flashback (violent propagation of a flame into the intake manifold) which limited operation to lower power output than was obtainable using liquid methanol. It was concluded that: an automobile could not be operated solely on dissociated or steam reformed methanol over the entire required power range - a supplementary fuel system or power source would be necessary to attain higher powers; the use of reformed mechanol, compared to liquid methanol, may result in a small improvement in thermal efficiency in the low power range; dissociated methanol is a better fuel than steam reformed methanol for use in a spark ignition engine; and use of dissociated or steam reformed methanol may result in lower exhaust emissions compared to liquid methanol.

Feasibility of CO/sub 2/ monitoring to assess air quality in mines using diesel equipment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daniel, J.H. Jr.

1987-01-01

The methodology includes: (1) establishing pollutant to CO/sub 2/ ratios for in-service equipment, (2) estimating pollutant concentrations from the ratios and in-mine CO/sub 2/ measurements, and (3) using an air quality index to combine the pollutants into a single number, which indicates the health hazard associated with the pollutants. For the methodology to be valid, the pollutant to CO/sub 2/ ratios must remain constant if engine operating conditions do not significantly change. However, due to the complex dynamics of the fuel injection system, the fuel-air combustion process, and the engine speed-load governing system, the pollutant to CO/sub 2/ ratios maymore » vary during repetitive, but transient engine speed-and-load operation. These transient effects were investigated. In addition, the influence of changing engine conditions due to engine maladjustment, and a practical means to evaluate engine condition were investigated to advance the methodology. The laboratory investigation determined that CO/sub 2/ is an effective indicator of engine exhaust pollutants. It was shown that the exhaust concentrations of carbon monoxide, carbon dioxide, oxides of nitrogen, hydrocarbons, and particulate matter do not significantly vary among repetitive, but transient engine speed-and-load duty cycles typical of in-service equipment. Based on an air quality index and threshold limit values, particulate matter exhibited the greatest adverse effect on air quality. Particulate mass was separated into volatile (organic soluble fraction) and nonvolatile (insoluble carbon fraction) components. Due to particulate concentrations, the engine operating conditions of overfueling and advanced injector timing had greater adverse effects on air quality than the conditions of retarded injector timing, intake air restriction, and Federal certification specifications.« less

Combustion system processes leading to corrosive deposits

NASA Technical Reports Server (NTRS)

Stearns, C. A.; Kohl, F. J.; Rosner, D. E.

1981-01-01

Degradation of turbine engine hot gas path components by high temperature corrosion can usually be associated with deposits even though other factors may also play a significant role. The origins of the corrosive deposits are traceable to chemical reactions which take place during the combustion process. In the case of hot corrosion/sulfidation, sodium sulfate was established as the deposited corrosive agent even when none of this salt enters the engine directly. The sodium sulfate is formed during the combustion and deposition processes from compounds of sulfur contained in the fuel as low level impurities and sodium compounds, such as sodium chloride, ingested with intake air. In other turbine and power generation situations, corrosive and/or fouling deposits can result from such metals as potassium, iron, calcium, vanadium, magnesium, and silicon.

40 CFR 1065.546 - Validation of minimum dilution ratio for PM batch sampling.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the raw exhaust flow rate based on the measured intake air molar flow rate and the chemical balance..., fuel rate measurements, and fuel properties, consistent with good engineering judgment. (b) Determine...) and dilute exhaust corrected for any removed water. (c) Use good engineering judgment to develop your...

Lactation in the Human Breast From a Fluid Dynamics Point of View.

PubMed

Negin Mortazavi, S; Geddes, Donna; Hassanipour, Fatemeh

2017-01-01

This study is a collaborative effort among lactation specialists and fluid dynamic engineers. The paper presents clinical results for suckling pressure pattern in lactating human breast as well as a 3D computational fluid dynamics (CFD) modeling of milk flow using these clinical inputs. The investigation starts with a careful, statistically representative measurement of suckling vacuum pressure, milk flow rate, and milk intake in a group of infants. The results from clinical data show that suckling action does not occur with constant suckling rate but changes in a rhythmic manner for infants. These pressure profiles are then used as the boundary condition for the CFD study using commercial ansys fluent software. For the geometric model of the ductal system of the human breast, this work takes advantage of a recent advance in the development of a validated phantom that has been produced as a ground truth for the imaging applications for the breast. The geometric model is introduced into CFD simulations with the aforementioned boundary conditions. The results for milk intake from the CFD simulation and clinical data were compared and cross validated. Also, the variation of milk intake versus suckling pressure are presented and analyzed. Both the clinical and CFD simulation show that the maximum milk flow rate is not related to the largest vacuum pressure or longest feeding duration indicating other factors influence the milk intake by infants.

Performance of a supercharged direct-injection stratified-charge rotary combustion engine

NASA Technical Reports Server (NTRS)

Bartrand, Timothy A.; Willis, Edward A.

1990-01-01

A zero-dimensional thermodynamic performance computer model for direct-injection stratified-charge rotary combustion engines was modified and run for a single rotor supercharged engine. Operating conditions for the computer runs were a single boost pressure and a matrix of speeds, loads and engine materials. A representative engine map is presented showing the predicted range of efficient operation. After discussion of the engine map, a number of engine features are analyzed individually. These features are: heat transfer and the influence insulating materials have on engine performance and exhaust energy; intake manifold pressure oscillations and interactions with the combustion chamber; and performance losses and seal friction. Finally, code running times and convergence data are presented.

Exhaust gas recirculation in a homogeneous charge compression ignition engine

DOEpatents

Duffy, Kevin P [Metamora, IL; Kieser, Andrew J [Morton, IL; Rodman, Anthony [Chillicothe, IL; Liechty, Michael P [Chillicothe, IL; Hergart, Carl-Anders [Peoria, IL; Hardy, William L [Peoria, IL

2008-05-27

A homogeneous charge compression ignition engine operates by injecting liquid fuel directly in a combustion chamber, and mixing the fuel with recirculated exhaust and fresh air through an auto ignition condition of the fuel. The engine includes at least one turbocharger for extracting energy from the engine exhaust and using that energy to boost intake pressure of recirculated exhaust gas and fresh air. Elevated proportions of exhaust gas recirculated to the engine are attained by throttling the fresh air inlet supply. These elevated exhaust gas recirculation rates allow the HCCI engine to be operated at higher speeds and loads rendering the HCCI engine a more viable alternative to a conventional diesel engine.

Preliminary Design of the Low Speed Propulsion Air Intake of the LAPCAT-MR2 Aircraft

NASA Astrophysics Data System (ADS)

Meerts, C.; Steelant, J.; Hendrick, P.

2011-08-01

A supersonic air intake has been designed for the low speed propulsion system of the LAPCAT-MR2 aircraft. Development has been based on the XB-70 aircraft air intake which achieves extremely high performances over a wide operation range through the combined use of variable geometry and porous wall suction for boundary layer control. Design of the LAPCAT-MR2 intake has been operated through CFD simulations using DLR TAU-Code (perfect gas model - Menter SST turbulence model). First, a new boundary condition has been validated into the DLR TAU-Code (perfect gas model) for porous wall suction modelling. Standard test cases have shown surprisingly good agreement with both theoretical predictions and experimental results. Based upon this validation, XB-70 air intake performances have been assessed through CFD simulations over the subsonic, transonic and supersonic operation regions and compared to available flight data. A new simulation strategy was deployed avoiding numerical instabilities when initiating the flow in both transonic and supersonic operation modes. First, the flow must be initiated with a far field Mach number higher than the target flight Mach number. Additionally, the inlet backpressure may only be increased to its target value once the oblique shock pattern downstream the intake compression ramps is converged. Simulations using that strategy have shown excellent agreement with in-flight measurements for both total pressure recovery ratio and variable geometry schedule prediction. The demarcation between stable and unstable operation could be well reproduced. Finally, a modified version of the XB-70 air intake has been integrated in the elliptical intake on the LAPCAT vehicle. Operation of this intake in the LAPCAT-MR2 environment is under evaluation using the same simulation strategy as the one developed for the XB-70. Performances are assessed at several key operation points to assess viability of this design. This information will allow in a next phase to better quantify the operation of the aerojet engines from take-off till the switch-over flight Mach number for the dual mode ramjet.

Salt intake and the validity of a salt intake assessment system based on a 24-h dietary recall method in pregnant Japanese women.

PubMed

Satoh, Michihiro; Tanno, Yumi; Hosaka, Miki; Metoki, Hirohito; Obara, Taku; Asayama, Kei; Hoshi, Kazuhiko; Suzuki, Masakuni; Mano, Nariyasu; Imai, Yutaka

2015-01-01

Information regarding salt intake in pregnant women in Japan is limited. An electronic system for the assessment of salt intake using a 24-h dietary recall method has been developed in Japan. The objectives of the present study were to investigate salt intake in pregnant women and to compare the salt intake estimated by the electronic salt intake assessment system with that measured by 24-h urinary salt excretion (24-hUNaCl). Data were collected on 24-hUNaCl and salt intake estimated by the salt intake assessment system for 35 pregnant Japanese women at approximately 20 weeks of gestation. The adjusted 24-hUNaCl (24-hUNaCl/[the number of urinations during the examination day--the number of missing urine collections] × the number of urinations during the examination day, g/day) was used as a standard. The mean adjusted 24-hUNaCl was 7.7 ± 2.5 g/day, and mean systolic/diastolic blood pressure values were 106.1 ± 8.6/62.8 ± 6.5 mmHg. The adjusted 24-hUNaCl was significantly correlated with the salt intake estimated by the salt intake assessment system (r = 0.47, p = 0.004). Bland-Altman analysis showed no significant mean difference (adjusted 24-hUNaCl--salt intake estimated by the assessment system = -0.36 g/day, p = 0.4) and no significant proportional bias (p = 0.1). These results suggest that pregnant women in Japan restrict their salt intake, at least when they are being examined for salt intake. They also suggest that repeated use of the described system may be useful in estimating salt intake in pregnant women.

Engineering approaches to energy balance and obesity: opportunities for novel collaborations and research: report of a joint national science foundation and national institutes of health workshop.

PubMed

Ershow, Abby G; Ortega, Alfonso; Timothy Baldwin, J; Hill, James O

2007-01-01

Energy balance disorders account for a large public health burden. The obesity epidemic in particular is one of the most rapidly evolving public health problems of our day. At present, two-thirds of American adults and one-sixth of American children and adolescents are considered either overweight or obese. Public health concern about obesity is high because of the increased risk and increased mortality of cardiovascular disease, Type 2 diabetes, many forms of cancer, gallbladder disease, and osteoarthritis. These risks increase with the severity of the obesity. Excess adipose tissue, representing fat storage, ultimately derives from an imbalance between energy intake and energy expenditure. Conversely, undesirable and inadvertent loss of body weight and muscle mass, as seen in aging and cachectic states of chronic diseases such as heart failure and cancer, have serious clinical and functional consequences without satisfactory clinical or behavioral solutions. Innovative engineering technologies could help to address unresolved problems in energy balance, intake, and expenditure. Novel sensors, devices, imaging technologies, nanotechnologies, biomaterials, technologies to detect biochemical markers of energy balance, mathematical modeling, systems biology, and other approaches could be developed, evaluated, and leveraged through multidisciplinary collaborations. Engineers, physical scientists, and mathematicians can work with scientists from other relevant disciplines who possess expertise in obesity and nutrition. Furthermore, the possibility of re-engineering the "built environment" to encourage higher levels of physical activity has been suggested as another promising and important approach to which engineers can contribute (see http://www.obesityresearch.nih.gov). Ultimately, systematic application of the "Engineering Approach" can help in developing the needed technologies and tools to facilitate research and eventually support therapeutic advances and behavioral change. This article summarizes important public health concerns related to disordered energy balance and describes research priorities identified at a recent National Science Foundation-National Institutes of Health workshop. Research funding opportunities are described as posted on the NIH Guide to Grants and Contracts (see http://www.nih.gov/grants/guide).

Engineering Approaches to Energy Balance and Obesity: Opportunities for Novel Collaborations and Research: Report of a Joint National Science Foundation and National Institutes of Health Workshop

PubMed Central

Ershow, Abby G.; Ortega, Alfonso; Timothy Baldwin, J.; Hill, James O.

2007-01-01

Energy balance disorders account for a large public health burden. The obesity epidemic in particular is one of the most rapidly evolving public health problems of our day. At present, two-thirds of American adults and one-sixth of American children and adolescents are considered either overweight or obese. Public health concern about obesity is high because of the increased risk and increased mortality of cardiovascular disease, Type 2 diabetes, many forms of cancer, gallbladder disease, and osteoarthritis. These risks increase with the severity of the obesity. Excess adipose tissue, representing fat storage, ultimately derives from an imbalance between energy intake and energy expenditure. Conversely, undesirable and inadvertent loss of body weight and muscle mass, as seen in aging and cachectic states of chronic diseases such as heart failure and cancer, have serious clinical and functional consequences without satisfactory clinical or behavioral solutions. Innovative engineering technologies could help to address unresolved problems in energy balance, intake, and expenditure. Novel sensors, devices, imaging technologies, nanotechnologies, biomaterials, technologies to detect biochemical markers of energy balance, mathematical modeling, systems biology, and other approaches could be developed, evaluated, and leveraged through multidisciplinary collaborations. Engineers, physical scientists, and mathematicians can work with scientists from other relevant disciplines who possess expertise in obesity and nutrition. Furthermore, the possibility of re-engineering the “built environment” to encourage higher levels of physical activity has been suggested as another promising and important approach to which engineers can contribute (see http://www.obesityresearch.nih.gov). Ultimately, systematic application of the “Engineering Approach” can help in developing the needed technologies and tools to facilitate research and eventually support therapeutic advances and behavioral change. This article summarizes important public health concerns related to disordered energy balance and describes research priorities identified at a recent National Science Foundation-National Institutes of Health workshop. Research funding opportunities are described as posted on the NIH Guide to Grants and Contracts (see http://www.nih.gov/grants/guide). PMID:19888386

Visualization of Air Particle Dynamics in an Engine Inertial Particle Separator

NASA Astrophysics Data System (ADS)

Wolf, Jason; Zhang, Wei

2015-11-01

Unmanned Aerial Vehicles (UAVs) are regularly deployed around the world in support of military, civilian and humanitarian efforts. Due to their unique mission profiles, these advanced UAVs utilize various internal combustion engines, which consume large quantities of air. Operating these UAVs in areas with high concentrations of sand and dust can be hazardous to the engines, especially during takeoff and landing. In such events, engine intake filters quickly become saturated and clogged with dust particles, causing a substantial decrease in the UAVs' engine performance and service life. Development of an Engine Air Particle Separator (EAPS) with high particle separation efficiency is necessary for maintaining satisfactory performance of the UAVs. Inertial Particle Separators (IPS) have been one common effective method but they experience complex internal particle-laden flows that are challenging to understand and model. This research employs an IPS test rig to simulate dust particle separation under different flow conditions. Soda lime glass spheres with a mean diameter of 35-45 microns are used in experiments as a surrogate for airborne particulates encountered during flight. We will present measurements of turbulent flow and particle dynamics using flow visualization techniques to understand the multiphase fluid dynamics in the IPS device. This knowledge can contribute to design better performing IPS systems for UAVs. Cleveland State University, Cleveland, Ohio, 44115.

Manifold absolute pressure estimation using neural network with hybrid training algorithm

PubMed Central

Selamat, Hazlina; Alimin, Ahmad Jais; Haniff, Mohamad Fadzli

2017-01-01

In a modern small gasoline engine fuel injection system, the load of the engine is estimated based on the measurement of the manifold absolute pressure (MAP) sensor, which took place in the intake manifold. This paper present a more economical approach on estimating the MAP by using only the measurements of the throttle position and engine speed, resulting in lower implementation cost. The estimation was done via two-stage multilayer feed-forward neural network by combining Levenberg-Marquardt (LM) algorithm, Bayesian Regularization (BR) algorithm and Particle Swarm Optimization (PSO) algorithm. Based on the results found in 20 runs, the second variant of the hybrid algorithm yields a better network performance than the first variant of hybrid algorithm, LM, LM with BR and PSO by estimating the MAP closely to the simulated MAP values. By using a valid experimental training data, the estimator network that trained with the second variant of the hybrid algorithm showed the best performance among other algorithms when used in an actual retrofit fuel injection system (RFIS). The performance of the estimator was also validated in steady-state and transient condition by showing a closer MAP estimation to the actual value. PMID:29190779

Engine Valve Actuation For Combustion Enhancement

DOEpatents

Reitz, Rolf Deneys; Rutland, Christopher J.; Jhavar, Rahul

2004-05-18

A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-stroke combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.

Engine valve actuation for combustion enhancement

DOEpatents

Reitz, Rolf Deneys [Madison, WI; Rutland, Christopher J [Madison, WI; Jhavar, Rahul [Madison, WI

2008-03-04

A combustion chamber valve, such as an intake valve or an exhaust valve, is briefly opened during the compression and/or power strokes of a 4-strokes combustion cycle in an internal combustion engine (in particular, a diesel or CI engine). The brief opening may (1) enhance mixing withing the combustion chamber, allowing more complete oxidation of particulates to decrease engine emissions; and/or may (2) delay ignition until a more desirable time, potentially allowing a means of timing ignition in otherwise difficult-to-control conditions, e.g., in HCCI (Homogeneous Charge Compression Ignition) conditions.

Ignition and combustion: Low compression ratio, high output diesel

NASA Technical Reports Server (NTRS)

1981-01-01

The feasibility of converting a spark ignition aircraft engine GTSI0-520 to compression ignition without increasing the peak combustion pressure of 1100 lbs/sq.in. was determined. The final contemplated utilized intake air heating at idle and light load and a compression ratio of about 10:1 with a small amount of fumigation (the addition of about 15% fuel into the combustion air before the cylinder). The engine used was a modification of a Continental-Teledyne gasoline engine cylinder from the GTSI0-520 supercharged aircraft engine.

Effects of Temperature on the Performance of a Small Internal Combustion Engine at Altitude

DTIC Science & Technology

2013-03-21

flexible diaphragm was attached to damp out pulses in the air flow pulsations . Their method of temperature control was electric heating of the intake air...42  Figure 14. Heat exchanger ................................................................................................ 45  Figure...15. Both liquid nitrogen lines from Dewar ............................................................ 45  Figure 16. Engine inlet flow path heat

Resonance vibrations in intake and exhaust pipes of in-line engines III : the inlet process of a four-stroke-cycle engine

NASA Technical Reports Server (NTRS)

Lutz, O

1940-01-01

Using a previously developed method, the boundary process of four-stroke-cycle engines are set up. The results deviate considerably from those obtained under the assumption that the velocity fluctuation is proportional to the cylinder piston motion. The deviation is less at the position of resonance frequencies. By the method developed, the effect of the resonance vibrations on the volumetric efficiency can be demonstrated.

Experimental investigation of in-cylinder air flow to optimize number of helical guide vanes to enhance DI diesel engine performance using mamey sapote biodiesel

NASA Astrophysics Data System (ADS)

Kumar, A. Raj; Janardhana Raju, G.; Hemachandra Reddy, K.

2018-03-01

The current research work investigates the influence of helical guide vanes in to the intake runner of a D.I diesel engine operating by the high viscous Mamey Sapote biodiesel to enhance in-cylinder suction air flow features. Helical guide vanes of different number of vanes are produced from 3D printing and placed in the intake manifold to examine the air flow characteristics. Four different helical guide vane devices namely 3, 4, 5 and 6 vanes of the same dimensions are tested in a D.I diesel engine operating with Mamey Sapote biodiesel blend. As per the experimental results of engine performance and emission characteristics, it is found that 5 vanes helical guide vane swirl device exhibited in addition number of increased improvements such as the brake power and bake thermal efficiency by 2.4% and 8.63% respectively and the HC, NOx, Carbon monoxide and, Smoke densities are reduced by 15.62%, 4.23%, 14.27% and 9.6% at peak load operating conditions as collate with normal engine at the same load. Hence this investigation concluded that Helical Guide Vane Devices successfully enhanced the in-cylinder air flow to improve better addition of Mamey Sapote biodiesel with air leading in better performance of the engine than without vanes.

Fuel film thickness measurements using refractive index matching in a stratified-charge SI engine operated on E30 and alkylate fuels

NASA Astrophysics Data System (ADS)

Ding, Carl-Philipp; Sjöberg, Magnus; Vuilleumier, David; Reuss, David L.; He, Xu; Böhm, Benjamin

2018-03-01

This study shows fuel film measurements in a spark-ignited direct injection engine using refractive index matching (RIM). The RIM technique is applied to measure the fuel impingement of a high research octane number gasoline fuel with 30 vol% ethanol content at two intake pressures and coolant temperatures. Measurements are conducted for an alkylate fuel at one operating case, as well. It is shown that the fuel volume on the piston surface increases for lower intake pressure and lower coolant temperature and that the alkylate fuel shows very little spray impingement. The fuel films can be linked to increased soot emissions. A detailed description of the calibration technique is provided and measurement uncertainties are discussed. The dependency of the RIM signal on refractive index changes is measured. The RIM technique provides quantitative film thickness measurements up to 0.9 µm in this engine. For thicker films, semi-quantitative results of film thickness can be utilized to study the distribution of impinged fuel.

An experimental study of the combustion characteristics in SCCI and CAI based on direct-injection gasoline engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, C.H.; Lee, K.H.

2007-08-15

Emissions remain a critical issue affecting engine design and operation, while energy conservation is becoming increasingly important. One approach to favorably address these issues is to achieve homogeneous charge combustion and stratified charge combustion at lower peak temperatures with a variable compression ratio, a variable intake temperature and a trapped rate of the EGR using NVO (negative valve overlap). This experiment was attempted to investigate the origins of these lower temperature auto-ignition phenomena with SCCI and CAI using gasoline fuel. In case of SCCI, the combustion and emission characteristics of gasoline-fueled stratified-charge compression ignition (SCCI) engine according to intake temperaturemore » and compression ratio was examined. We investigated the effects of air-fuel ratio, residual EGR rate and injection timing on the CAI combustion area. In addition, the effect of injection timing on combustion factors such as the start of combustion, its duration and its heat release rate was also investigated. (author)« less

Monovalve with integrated fuel injector and port control valve, and engine using same

DOEpatents

Milam, David M.

2001-11-06

An engine includes an engine casing that defines a hollow piston cavity separated from an exhaust passage and an intake passage by a valve seat. A gas exchange valve member is positioned adjacent the valve seat and is moveable between an open position and a closed position. The gas exchange valve member also defines an opening that opens into the hollow piston cavity. A needle valve member is positioned in the gas exchange valve member adjacent a nozzle outlet and is moveable between an inject position and a blocked position. A port control valve member, which has a hydraulic surface, is mounted around the gas exchange valve member and moveable between an intake position and an exhaust position. A pilot valve is moveable between a first position at which the port control hydraulic surface is exposed to a source of high pressure fluid, and a second position at which the port control hydraulic surface is exposed to a source of low pressure fluid.

A study of optimum cowl shapes and flow port locations for minimum drag with effective engine cooling, volume 1

NASA Technical Reports Server (NTRS)

Fox, S. R.; Smetana, F. O.

1980-01-01

The contributions to the cruise drag of light aircraft arising from the shape of the engine cowl and the forward fuselage area and also that resulting from the cooling air mass flow through intake and exhaust sites on the nacelle were analyzed. The methods employed for the calculation of the potential flow about an arbitrary three dimensional body are described with modifications to include the effects of boundary layer displacement thickness, a nonuniform onset flow field (such as that due to a rotating propeller), and the presence of air intakes and exhausts. A simple, reliable, largely automated scheme to better define or change the shape of a body is also presented. A technique was developed which can yield physically acceptable skin friction and pressure drag coefficients for isolated light aircraft bodies. For test cases on a blunt nose Cessna 182 fuselage, the technique predicted drag reductions as much as 28.5% by body recontouring and proper placements and sizing of the cooling air intakes and exhausts.

View of Irving Intake System showing shed and steel flume. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Irving Intake System showing shed and steel flume. Looking west-northwest - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

Flow in water-intake pump bays: A guide for utility engineers. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ettema, R.

1998-09-01

This report is intended to serve as a guide for power-plant engineers facing problems with flow conditions in pump bays in water-intake structures, especially those located alongside rivers. The guide briefly introduces the typical prevailing flow field outside of a riverside water intake. That flow field often sets the inflow conditions for pump bays located within the water intake. The monograph then presents and discusses the main flow problems associated with pump bays. The problems usually revolve around the formation of troublesome vortices. A novel feature of this monograph is the use of numerical modeling to reveal diagnostically how themore » vortices form and their sensitivities to flow conditions, such as uniformity of approach flow entering the bay and water-surface elevation relative to pump-bell submergence. The modeling was carried out using a computer code developed specially for the present project. Pump-bay layouts are discussed next. The discussion begins with a summary of the main variables influencing bay flows. The numerical model is used to determine the sensitivities of the vortices to variations in the geometric parameters. The fixes include the use of flow-control vanes and suction scoops for ensuring satisfactory flow performance in severe flow conditions; notably flows with strong cross flow and shallow flows. The monograph ends with descriptions of modeling techniques. An extensive discussion is provided on the use of numerical model for illuminating bay flows. The model is used to show how fluid viscosity affects bay flow. The effect of fluid viscosity is an important consideration in hydraulic modeling of water intakes.« less

Monovalve with integrated fuel injector and port control valve, and engine using same

DOEpatents

Milam, David M.

2002-01-01

Each cylinder of an internal combustion engine includes a combined gas exchange valve and fuel injector with a port control valve. The port control valve operates to open either an intake passage or an exhaust passage. The operation of the combined device is controlled by a pair of electrical actuators. The device is hydraulically actuated.

Modeling and Simulation of a Free-Piston Engine with Electrical Generator Using HCCI Combustion

NASA Astrophysics Data System (ADS)

Alrbai, Mohammad

Free-piston engines have the potential to challenge the conventional crankshaft engines by their design simplicity and higher operational efficiency. Many studies have been performed to overcome the limitations of the free-piston devices especially the stability and control issues. The investigations within the presented dissertation aim to satisfy many objectives by employing the approach of chemical kinetics to present the combustion process in the free-piston engine. This approach in addition to its advanced accuracy over the empirical methods, it has many other features like the ability to analyze the engine emissions. The effect of the heat release rate (HRR) on the engine performance is considered as the main objective. Understanding the relation between the HRR and the piston dynamics helps in enhancing the system efficiency and identifying the parameters that affect the overall performance. The dissertation covers some other objectives that belongs to the combustion phasing. Exhaust gas recirculation (EGR), equivalence ratio and the intake temperature represent the main combustion parameters, which have been discussed in this dissertation. To obtain the stability in system performance, the model requires a proper controller to simulate the operation and manage the different system parameters; for this purpose, different controlling techniques have been employed. In addition, the dissertation considers some other topics like engine emissions, fuels and fuels mechanisms. The model of the study describes the processes within a single cylinder, two stroke engine, which includes springs to support higher frequencies, reduce cyclic variations and sustain the engine compression ratio. An electrical generator presents the engine load; the generator supports different load profiles and play the key role in controlling the system. The 1st law of thermodynamics and Newton's 2nd law are applied to couple the piston dynamics with the engine thermodynamics. The model governing equations represent a single zone perfectly stirred reactor (PSR) which contain a perfect mixing ideal gas mixture. The chemical kinetics approach is applied using Cantera/ MATLABRTM toolbox, which presents the combustion process. In this research, a homogenous charge compression ignition (HCCI) at different operational conditions is used. HCCI engines have high efficiencies and low emissions and can work within a wide range of fuels. The results have been presented in a multi-cycle simulation and a parametric study forms. In the case of the multi-cycle simulation, a 100 cycles of the engine operation have been simulated. The overall work that is delivered to the electrical generator presents 47% of the total fuel energy. The model indicates an average frequency of 125 Hz along the operational cycles. In order to eliminate the cyclic variations and ensure a continuous operation, a proportional derivative (PD) controller has been employed. The controller adjusts the generator load in order to minimize the difference between the bottom dead center (BDC) locations along the operation cycles. The PD controller shows weakness in achieving the full steady state operation, for this purpose; a proportional integral (PI) controller has been implemented. The PI controller seeks to achieve a specific compression ratio. The results show that; the PI controller indicates unique behavior after 15 cycles of operation where the model ended to fluctuate between two compression ratios only. The complex relation between the thermodynamics and the dynamics of the engine is the greatest challenge in examining the effectiveness of the PI controller. In the parametric investigations, EGR examinations show that NOx emission is reduced to less than the half, as 30 % of EGR is used; this occurs due to the EGR thermal and dilution effects, which cause significant drop in the peak bulk temperature and CO emissions as well. Under the applied conditions, EGR has the ability to raise the work output ratio by increasing the engine compression ratio. The examination of the EGR temperature on the engine performance indicates that cooled EGR charges have the advantage over the hot EGR mixtures on enhancing the work output ratio. At the same time, EGR temperature affects the NOx formation by speeding its instantaneous reactions rate. The dissertation includes a study of the effect of the intake temperature and the equivalence ratio (φ) as well. The increasing in the intake temperature reduce the time needed for ignition, but leads to a reduction in the work output ratio at the same time. Such results can help in studying high knock resistance fuels where ignition delay is a matter. In the case of the equivalence ratio, lean mixtures show efficiencies that exceed 50% compared to those at the stoichiometric conditions. In the case of the ultra-lean (φ<0.5) combustion, the results show that the NOx emission is with the minimal levels as well as the CO and the unburned hydrocarbons (UHC) emissions. Sensitivity analysis to the chemical kinetic mechanism for the fuel combustion has been presented also in the dissertation. Many mechanisms for different fuels have been investigated, for example; a modified mechanism for Methane that includes 36 species and 222 reactions has been compared with the full GRI 3.0 mechanism (53 species and 325 reactions). The results of this comparison indicate that the modified mechanism has the potential to replace the full one in some cases like in demonstrating the engine operation, but not in the engine emissions analysis.

Materials-Enabled High-Efficiency (MEHE) Heavy-Duty Diesel Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kass, M.; Veliz, M.

2011-09-30

The purpose of this Cooperative Research and Development Agreement (CRADA) between UTBattelle, Inc. and Caterpillar, Inc. was to improve diesel engine efficiency by incorporating advanced materials to enable higher combustion pressures and temperatures necessary for improved combustion. The project scope also included novel materials for use in advanced components and designs associated with waste-heat recovery and other concepts for improved thermal efficiency. Caterpillar initially provided ORNL with a 2004 Tier 2 C15 ACERT diesel engine (designed for on-highway use) and two 600 hp motoring dynamometers. The first year of the CRADA effort was focused on establishing a heavy-duty experimental enginemore » research cell. First year activities included procuring, installing and commissioning the cell infrastructure. Infrastructure components consisted of intake air handling system, water tower, exhaust handling system, and cell air conditioning. Other necessary infrastructure items included the fuel delivery system and bottled gas handling to support the analytical instrumentation. The second year of the CRADA focused on commissioning the dynamometer system to enable engine experimentation. In addition to the requirements associated with the dynamometer controller, the electrical system needed a power factor correction system to maintain continuity with the electrical grid. During the second year the engine was instrumented and baseline operated to confirm performance and commission the dynamometer. The engine performance was mapped and modeled according to requirements provided by Caterpillar. This activity was further supported by a Work-for-Others project from Caterpillar to evaluate a proprietary modeling system. A second Work-for-Others activity was performed to evaluate a novel turbocharger design. This project was highly successful and may lead to new turbocharger designs for Caterpillar heavy-duty diesel engines. During the third (and final) year of the CRADA, a novel valve material was evaluated to assess high temperature performance and durability. A series of prototype valves, composed of a unique nickel-alloy was placed in the engine head. The engine was aggressively operated using a transient test cycle for 200 hours. The valve recession was periodically measured to determine valve performance. Upon completion of the test the valves were removed and returned to Caterpillar for additional assessment. Industrial in-kind support was available throughout the project period. Review of the status and research results were carried out on a regular basis (meetings and telecons) which included direction for future work activities. A significant portion of the industrial support was in the form of information exchange and technical consultation.« less

Visualization of flows in a motored rotary combustion engine using holographic interferometry

NASA Technical Reports Server (NTRS)

Hicks, Y. R.; Schock, H. J.; Craig, J. E.; Umstatter, H. L.; Lee, D. Y.

1986-01-01

The use of holographic interferometry to view the small- and large-scale flow field structures in the combustion chamber of a motored Wankel engine assembly is described. In order that the flow patterns of interest could be observed, small quantities of helium were injected with the intake air. Variation of the air flow patterns with engine speed, helium flow rate, and rotor position are described. The air flow at two locations within the combustion chamber was examined using this technique.

Volcanic ash ingestion by a large gas turbine aeroengine: fan-particle interaction

NASA Astrophysics Data System (ADS)

Vogel, Andreas; Clarkson, Rory; Durant, Adam; Cassiani, Massimo; Stohl, Andreas

2016-04-01

Airborne particles from explosive volcanic eruptions are a major safety threat for aviation operations. The fine fraction of the emitted particles (<63 microns diameter) may remain in the atmosphere for days, or even weeks, and can affect commercial air traffic routes. Over the past century, there have been a considerable number of aircraft encounters with drifting volcanic ash clouds. Particles ingested into the engine cause erosion of upstream surfaces of compressor fan blades and rotor-path components, and can also cause contamination or blockage of electrical systems and the fuel system such as fuel nozzles and air bleed filters. Ash particles that enter the hot-section of the engine (combustor and turbine stages; temperature between 1400-1800°C) are rapidly heated above the glass transition temperature (about 650-1000°C) and become soft (or form a melt) and can stick as re-solidified deposits on nozzle guide vanes. The glass deposits change the internal aerodynamic airflow in the engine and can affect the cooling capability of the different components by clogging the cooling inlets/outlets, which can lead to a loss of power or flame-out. The nature of volcanic ash ingestion is primarily influenced by the fan at the front of the engine which produces the thrust that drives the aircraft. The ingested air is split between the core (compressor/combustor/turbine) and bypass (thrust) at a ratio of typically between, 1:5-10 on modern engines. Consequently, the ash particles are fractionated between the core and bypass by the geometry and dynamics of the fan blades. This study uses computational fluid dynamics (CFD) simulations of particle-laden airflows into a turbofan engine under different atmospheric and engine operation conditions. The main aim was to investigate the possible centrifugal effect of the fan blades as a function of particle size, and to relate this to the core intake concentration. We generated a generic 3D axial high-bypass turbofan engine using realistic dimensions of the turbofan, engine intake and other aerodynamically relevant parts. The CFD experiments include three scenarios of aircraft performance (climb, cruise and descent) and for two different typical altitude ranges (10000 and 39000 ft). The fluid dynamics simulations were carried out using a commercial code (CD Adapco STAR-CCM+ with an implicit coupled flow and energy algorithm) for compressible high-speed flows including a Lagrangian particle-tracking model for the simulation of the particle behaviour for typical atmospheric particle size ranges between 1 and 100 μm. The simulations indicate that the predominant proportion of larger particles (> 20 microns) tend to be transported into the bypass duct of the engine (by the centrifugal effect of the fan), whereas the smaller particles follow the fluid flow streamlines and are distributed homogenously in the engine (bypass ducts and core region). This result is significant as it indicates that the absolute ash mass that causes issues for aeroengine operation is a fraction of the ambient (observed or forecast) ash quantity.

Effects of bending-torsional duct-induced swirl distortion on aerodynamic performance of a centrifugal compressor

NASA Astrophysics Data System (ADS)

Hou, Hongjuan; Wang, Leilei; Wang, Rui; Yang, Yanzhao

2017-04-01

A turbocharger compressor working in commercial vehicles, especially in some passenger cars, often works together with some pipes with complicated geometry as an air intake system, due to limit of available space in internal combustion engine compartments. These pipes may generate various distortions of physical parameters of the air at the inlet of the compressor and therefore the compressor aerodynamic performance deteriorates. Sometimes, the turbocharging engine fails to work at some operation points. This paper investigates the effects of various swirl distortions induced by different bending-torsional intake ducts on the aerodynamic performance of a turbocharger compressor by both 3D numerical simulations and experimental measurements. It was found that at the outlet of the pipes the different inlet ducts can generate different swirl distortions, twin vortices and bulk-like vortices with different rotating directions. Among them, the bulk-like vortices not only affect seriously the pressure distribution in the impeller domain, but also significantly deteriorate the compressor performance, especially at high flow rate region. And the rotating direction of the bulk-like vortices is also closely associated with the efficiency penalty. Besides the efficiency, the transient flow rate through a single impeller channel, or the asymmetric mass flow crossing the whole impeller, can be influenced by two disturbances. One is from the upstream bending-torsional ducts; other one is from the downstream volute.

Fabrication of a smart air intake structure using shape memory alloy wire embedded composite

NASA Astrophysics Data System (ADS)

Jung, Beom-Seok; Kim, Min-Saeng; Kim, Ji-Soo; Kim, Yun-Mi; Lee, Woo-Yong; Ahn, Sung-Hoon

2010-05-01

Shape memory alloys (SMAs) have been actively studied in many fields utilizing their high energy density. Applying SMA wire-embedded composite to aerospace structures, such as air intake of jet engines and guided missiles, is attracting significant attention because it could generate a comparatively large actuating force. In this research, a scaled structure of SMA wire-embedded composite was fabricated for the air intake of aircraft. The structure was composed of several prestrained Nitinol (Ni-Ti) SMA wires embedded in ∩-shape glass fabric reinforced plastic (GFRP), and it was cured at room temperature for 72 h. The SMA wire-embedded GFRP could be actuated by applying electric current through the embedded SMA wires. The activation angle generated from the composite structure was large enough to make a smart air intake structure.

The Waukesha Turbocharger Control Module: A tool for improved engine efficiency and response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zurlo, J.R.; Reinbold, E.O.; Mueller, J.

1996-12-31

The Waukesha Turbocharger Control Module allows optimum control of turbochargers on lean burn gaseous fueled engines. The Turbocharger Control Module is user programmed to provide either maximum engine efficiency or best engine response to load changes. In addition, the Turbocharger Control Module prevents undesirable turbocharger surge. The Turbocharger Control Module consists of an electronic control box, engine speed, intake manifold pressure, ambient temperature sensors, and electric actuators driving compressor bypass and wastegate valves. The Turbocharger Control Module expands the steady state operational environment of the Waukesha AT27GL natural gas engine from sea level to 1,525 m altitude with one turbochargermore » match and improves the engine speed turn down by 80 RPM. Finally, the Turbocharger Control Module improves engine response to load changes.« less

Fluid flow and fuel-air mixing in a motored two-dimensional Wankel rotary engine

NASA Technical Reports Server (NTRS)

Shih, T. I.-P.; Nguyen, H. L.; Stegeman, J.

1986-01-01

The implicit-factored method of Beam and Warming was employed to obtain numerical solutions to the conservation equations of mass, species, momentum, and energy to study the unsteady, multidimensional flow and mixing of fuel and air inside the combustion chambers of a two-dimensional Wankel rotary engine under motored conditions. The effects of the following engine design and operating parameters on fluid flow and fuel-air mixing during the intake and compression cycles were studied: engine speed, angle of gaseous fuel injection during compression cycle, and speed of the fuel leaving fuel injector.

Fluid flow and fuel-air mixing in a motored two-dimensional Wankel rotary engine

NASA Astrophysics Data System (ADS)

Shih, T. I.-P.; Nguyen, H. L.; Stegeman, J.

1986-06-01

The implicit-factored method of Beam and Warming was employed to obtain numerical solutions to the conservation equations of mass, species, momentum, and energy to study the unsteady, multidimensional flow and mixing of fuel and air inside the combustion chambers of a two-dimensional Wankel rotary engine under motored conditions. The effects of the following engine design and operating parameters on fluid flow and fuel-air mixing during the intake and compression cycles were studied: engine speed, angle of gaseous fuel injection during compression cycle, and speed of the fuel leaving fuel injector.

View of Irving intake system showing shed and a portion ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Irving intake system showing shed and a portion of the concrete cover (foreground). Looking south-southwest - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

ADVANCED HEAT TRANSFER TEST FACILITY, TRA666A. ELEVATIONS. ROOF FRAMING PLAN. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ADVANCED HEAT TRANSFER TEST FACILITY, TRA-666A. ELEVATIONS. ROOF FRAMING PLAN. CONCRETE BLOCK SIDING. SLOPED ROOF. ROLL-UP DOOR. AIR INTAKE ENCLOSURE ON NORTH SIDE. F.C. TORKELSON 842-MTR-666-A5, 8/1966. INL INDEX NO. 531-0666-00-851-152258, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Engine combustion control at low loads via fuel reactivity stratification

DOEpatents

Reitz, Rolf Deneys; Hanson, Reed M; Splitter, Derek A; Kokjohn, Sage L

2014-10-07

A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.

Three-dimensional modeling of diesel engine intake flow, combustion and emissions

NASA Technical Reports Server (NTRS)

Reitz, R. D.; Rutland, C. J.

1992-01-01

A three-dimensional computer code (KIVA) is being modified to include state-of-the-art submodels for diesel engine flow and combustion: spray atomization, drop breakup/coalescence, multi-component fuel vaporization, spray/wall interaction, ignition and combustion, wall heat transfer, unburned HC and NOx formation, soot and radiation, and the intake flow process. Improved and/or new submodels which were completed are: wall heat transfer with unsteadiness and compressibility, laminar-turbulent characteristic time combustion with unburned HC and Zeldo'vich NOx, and spray/wall impingement with rebounding and sliding drops. Results to date show that adding the effects of unsteadiness and compressibility improves the accuracy of heat transfer predictions; spray drop rebound can occur from walls at low impingement velocities (e.g., in cold-starting); larger spray drops are formed at the nozzle due to the influence of vaporization on the atomization process; a laminar-and-turbulent characteristic time combustion model has the flexibility to match measured engine combustion data over a wide range of operating conditions; and finally, the characteristic time combustion model can also be extended to allow predictions of ignition. The accuracy of the predictions is being assessed by comparisons with available measurements. Additional supporting experiments are also described briefly. To date, comparisons with measured engine cylinder pressure and heat flux data were made for homogeneous charge, spark-ignited and compression-ignited engines. The model results are in good agreement with the experiments.

The interaction of oblique shocks in a shock layer in hypersonic flow

NASA Astrophysics Data System (ADS)

Baird, John P.; Thomas, J.; Joe, W. S.

1990-07-01

A new generation of spacecraft is currently being designed. Some of the proposed concepts involve the use of air breathing engines during part of the earth to orbit flight phase. In the case of the HOTOL concept studies, the engine intakes will be covered for the re-entry phase, and will protrude through the windward surface shock layer during re-entry. An understanding of the complex flow which will occur over the closed intakes during the hypersonic re-entry is important for at least two reasons. Firstly, the heat transfer on the surfaces has to be estimated to allow for suitable intake cover design. Secondly, the wake of the intakes interacts with the underside of the wings and control surfaces, and could possibly cause handling anomalies. The present paper describes a study in which a simplified model involving a double wedge mounted on a flat plate at incidence (Fig. 1) was tested in the Free Piston Shock Tunnel T3 at the Australian National University. Heat transfer measurements and shock luminosity photographs were recorded at two operating conditions, one with a stagnation enthalpy of 22 MJ/kg and the other with 2.8 MJ/kg. A flow analysis which identified a number of significantly different flow regimes was also performed. Heat transfer measurements indicate that heating rates well in excess of those expected at the stagnation point on the nose of the spacecraft can be expected. The results also highlighted a compromise which is a necessary feature of this type of design. The compromise involves a trade off between intake efficiency during the air breathing phase of operation and the reduction of heat transfer during the re-entry phase.

Controls and measurements of KU engine test cells for biodiesel, SynGas, and assisted biodiesel combustion

NASA Astrophysics Data System (ADS)

Cecrle, Eric Daniel

This thesis is comprised of three unique data acquisition and controls (CDAQ) projects. Each of these projects differs from each other; however, they all include the concept of testing renewable or future fuel sources. The projects were the following: University of Kansas's Feedstock-to-Tailpipe Initiative's Synthesis Gas Reforming rig, Feedstock-to-Tailpipe Initiative's Biodiesel Single Cylinder Test Stand, and a unique Reformate Assisted Biodiesel Combustion architecture. The main responsibility of the author was to implement, develop and test CDAQ systems for the projects. For the Synthesis Gas Reforming rig, this thesis includes a report that summarizes the analysis and solution of building a controls and data acquisition system for this setup. It describes the purpose of the sensors selected along with their placement throughout the system. Moreover, it includes an explanation of the planned data collection system, along with two models describing the reforming process useful for system control. For the Biodiesel Single Cylinder Test Stand, the responsibility was to implement the CDAQ system for data collection. This project comprised a variety of different sensors that are being used collect the combustion characteristics of different biodiesel formulations. This project is currently being used by other graduates in order to complete their projects for subsequent publication. For the Reformate Assisted Biodiesel Combustion architecture, the author developed a reformate injection system to test different hydrogen and carbon monoxide mixtures as combustion augmentation. Hydrogen combustion has certain limiting factors, such as pre-ignition in spark ignition engines and inability to work as a singular fuel in compression ignition engines. To offset these issues, a dual-fuel methodology is utilized by injecting a hydrogen/carbon monoxide mixture into the intake stream of a diesel engine operating on biodiesel. While carbon monoxide does degrade some of the desirable properties of hydrogen, it acts partially like a diluent in order to prevent pre-ignition from occurring. The result of this mixture addition allows the engine to maintain power while reducing biodiesel fuel consumption with a minimal NOx emissions increase.

The automotive application of discontinuously reinforced TiB-Ti composites

NASA Astrophysics Data System (ADS)

Saito, Takashi

2004-05-01

In 1998, Toyota Motor Corporation adopted intake valves and exhaust valves made of titanium-based alloys for the engine of its Altezza. Both valves were manufactured via a newly developed cost-effective powder metallurgy process. The exhaust valve is made of a newly developed titanium metal-matrix composite (MMC). The valve has achieved sufficient durability and reliability with a manufacturing cost acceptable for the mass-produced automobile engine components.

Thermochemistry of CaO-MgO-Al2O3-SiO2 (CMAS) and Advanced Thermal and Environmental Barrier Coating Systems

NASA Technical Reports Server (NTRS)

Costa, Gustavo C. C.; Zhu, Dongming

2016-01-01

CaO-MgO-Al2O3-SiO2 (CMAS) oxides are constituents in a broad number of materials and minerals which have recently inferred to discussions in materials science, planetary science, geochemistry and cosmochemistry communities. In materials science, there is increasing interest in the degradation studies of thermal (TBC) and environmental (EBC) barrier coatings of gas turbines by molten CMAS. These coatings have been explored to be applied on silicon-based ceramics and composites which are lighter and more temperature capable hot-section materials of gas turbines than the current Ni-based superalloys. The degradation of the coatings occurs when CMAS minerals carried by the intake air into gas turbines, e.g. in aircraft engines, reacts at high temperatures (1000C) with the coating materials. This causes premature failure of the static and rotating components of the turbine engines. We discuss some preliminary results of the reactions between CMAS and Rare-Earth (RE Y, Yb and Gd) oxide stabilized ZrO2 systems, and stability of the resulting oxides and silicates.

REDUCTION OF EMISSIONS FROM A HIGH SPEED FERRY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson,G.; Gautam, M; Clark, N

2003-08-24

Emissions from marine vessels are being scrutinized as a major contributor to the total particulate matter (TPM), oxides of sulfur (SOx) and oxides of nitrogen (NOx) environmental loading. Fuel sulfur control is the key to SOx reduction. Significant reductions in the emissions from on-road vehicles have been achieved in the last decade and the emissions from these vehicles will be reduced by another order of magnitude in the next five years: these improvements have served to emphasize the need to reduce emissions from other mobile sources, including off road equipment, locomotives, and marine vessels. Diesel-powered vessels of interest include oceanmore » going vessels with low- and medium-speed engines, as well as ferries with high speed engines, as discussed below. A recent study examined the use of intake water injection (WIS) and ultra low sulfur diesel (ULSD) to reduce the emissions from a high-speed passenger ferry in southern California. One of the four Detroit Diesel 12V92 two-stroke high speed engines that power the Waverider (operated by SCX, inc.) was instrumented to collect intake airflow, fuel flow, shaft torque, and shaft speed. Engine speed and shaft torque were uniquely linked for given vessel draft and prevailing wind and sea conditions. A raw exhaust gas sampling system was utilized to measure the concentration of NOx, carbon dioxide (CO2), and oxygen (O2) and a mini dilution tunnel sampling a slipstream from the raw exhaust was used to collect TPM on 70 mm filters. The emissions data were processed to yield brake-specific mass results. The system that was employed allowed for redundant data to be collected for quality assurance and quality control. To acquire the data, the Waverider was operated at five different steady state speeds. Three modes were in the open sea off Oceanside, CA, and idle and harbor modes were also used. Data have showed that the use of ULSD along with water injection (WIS) could significantly reduce the emissions of NOx and PM while not affecting fuel consumption or engine performance compared to the baseline marine diesel. The results showed that a nominal 40% reduction in TPM was realized when switching from the marine diesel to the ULSD. A small reduction in NOx was also shown between the marine fuel and the ULSD. The implementation of the WIS showed that NOx was reduced significantly by between 11% and 17%, depending upon the operating condition. With the WIS, the TPM was reduced by a few percentage points, which was close to the confidence in measurement.« less

Technical note: Validation of an automated system for monitoring and restricting water intake in group-housed beef steers.

PubMed

Allwardt, K; Ahlberg, C; Broocks, A; Bruno, K; Taylor, A; Place, S; Richards, C; Krehbiel, C; Calvo-Lorenzo, M; DeSilva, U; VanOverbeke, D; Mateescu, R; Goad, C; Rolf, M M

2017-09-01

The Insentec Roughage Intake Control (RIC) system has been validated for the collection of water intake; however, this system has not been validated for water restriction. The objective of this validation was to evaluate the agreement between direct observations and automated intakes collected by the RIC system under both ad libitum and restricted water conditions. A total of 239 crossbred steers were used in a 3-d validation trial, which assessed intake values generated by the RIC electronic intake monitoring system for both ad libitum water intake ( = 122; BASE) and restricted water intake ( = 117; RES). Direct human observations were collected on 4 Insentec water bins for three 24-h periods and three 12-h periods for BASE and RES, respectively. An intake event was noted by the observer when the electronic identification of the animal was read by the transponder and the gate lowered, and starting and ending bin weights were recorded for each intake event. Data from direct observations across each validation period were compared to automated observations generated from the RIC system. Missing beginning or ending weight values for visual observations occasionally occurred due to the observer being unable to capture the value before the monitor changed when bin activity was high. To estimate the impact of these missing values, analyses denoted as OBS were completed with the incomplete record coded as missing data. These analyses were contrasted with analyses where observations with a single missing beginning or end weight (but not both) were assumed to be identical to that which was recorded by the Insentec system (OBS). Difference in mean total intake across BASE steers was 0.60 ± 2.06 kg OBS (0.54 ± 1.99 kg OBS) greater for system observations than visual observations. The comparison of mean total intake across the 3 RES validation days was 0.53 ± 2.30 kg OBS (0.13 ± 1.83 kg OBS) greater for system observations than direct observations. Day was not a significant source of error in this study ( > 0.05). These results indicate that the system was capable of limiting water of individual animals with reasonable accuracy, although errors are slightly higher during water restriction than during ad libitum access. The Insentec system is a suitable resource for monitoring individual water intake of growing, group-housed steers under ad libitum and restricted water conditions.

Pressure and temperature effects on fuels with varying octane sensitivity at high load in SI engines

DOE PAGES

Szybist, James P.; Splitter, Derek A.

2017-01-06

The octane sensitivity (S), defined as the difference between the Research Octane Number (RON) and the Motor Octane Number (MON), is of increasing interest in spark ignition (SI) engines because of its relevance to knock resistance at boosted high load conditions. In this study, three fuels with nearly constant RON (99.2-100) and varying S (S = 0, 6.5, and 12) are operated at the knock limited spark advance (KLSA) at nominal engine loads of 10, 15, and 20 bar IMEP in a single cylinder SI engine with side-mount direct injection fueling, at λ =1 stoichiometry. At each load condition, themore » intake manifold temperature is swept from 35 °C to 95 °C to alter the temperature and pressure history of the charge. Results show that at the 10 bar IMEP condition, knock resistance is inversely proportional to fuel S where the S=0 fuel is the most knock resist, but as load increases the trend reverses and knock resistance becomes proportional to fuel S, and the S=12 fuel is the most knock resistant. The reversal of knock resistance as a function of S with load it is attributed to changing fuel ignition delay, as bulk gas intermediate temperature heat release (ITHR) is observed for the S = 0 several crank angles prior to the spark command and ITHR magnitude is a function of increasing intake temperature. As intake temperature continued to increase, the S=0 fuel transitioned from ITHR to low-temperature heat release (LTHR) prior to the spark event. At the highest load and intake temperature, 95 C, the S=0 fuel exhibits distinct LTHR and negative temperature coefficient (NTC), and the intermediate S value fuel (S=6.5) exhibited distinct ITHR behavior several crank angles prior to the spark command. However, for the tested conditions, the S=12 fuel exhibits neither ITHR nor LTHR. To understand the measured trends, chemical kinetic modeling is used to elucidate the fuel specific dependencies on in-cylinder temperature and pressure history. Lastly, the bulk gas composition change that occurs for fuels and conditions exhibiting ITHR and LTHR is analyzed in the modeling, including their implications on flame speed and combustion stability at late phasing. Furthermore, the combined findings illustrate the commonality and utility of fuel S, ITHR, LTHR, and NTC across a wide range of conditions, and the associated implications of fuel S in highly boosted modern GDI SI engines relative to the RON and MON tests.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

ALTIC, NICK A

In March 2011, the USNS Bridge was deployed off northeastern Honshu, Japan with the carrier USS Ronald Reagan to assist with relief efforts after the 2011 Tōhoku earthquake and tsunami. During that time, the Bridge was exposed to air-borne radioactive materials leaking from the damaged Fukushima I Nuclear Power Plant. The proximity of the Bridge to the air-borne impacted area resulted in the contamination of the ship’s air-handling systems and the associated components, as well as potential contamination of other ship surfaces due to either direct intake/deposition or inadvertent spread from crew/operational activities. Preliminary surveys in the weeks after themore » event confirmed low-level contamination within the heating, ventilation, and air conditioning (HVAC) ductwork and systems, and engine and other auxiliary air intake systems. Some partial decontamination was performed at that time. In response to the airborne contamination event, Military Sealift Fleet Support Command (MSFSC) contracted Oak Ridge Associated Universities (ORAU), under provisions of the Oak Ridge Institute for Science and Education (ORISE) contract, to assess the radiological condition of the Bridge. Phase I identified contamination within the CPS filters, ventilation systems, miscellaneous equipment, and other suspect locations that could not accessed at that time (ORAU 2011b). Because the Bridge was underway during the characterization, all the potentially impacted systems/spaces could not be investigated. As a result, MSFSC contracted with ORAU to perform Phase II of the characterization, specifically to survey systems/spaces previously inaccessible. During Phase II of the characterization, the ship was in port to perform routine maintenance operations, allowing access to the previously inaccessible systems/spaces.« less

Research on EHN additive on the diesel engine combustion characteristics in plateau environment

NASA Astrophysics Data System (ADS)

Sun, Zhixin; Li, Ruoting; Wang, Xiancheng; Hu, Chuan

2017-03-01

Aiming at the combustion deterioration problem of diesel engine in plateau environment, a bench test was carried out for the effects of EHN additive on combustion characteristics of the diesel engine with intake pressure of 0.68 kPa. Test results showed that with the full load working condition of 1 400 r/min: Cylinder pressure and pressure uprising rate decreased with EHN additive added in, mechanical load on the engine could be relieved; peak value of the heat release rate decreased and its occurrence advanced, ignition delay and combustion duration were shortened; cylinder temperature and exhaust gas temperature declined, thermal load on the engine could be relieved, output torque increased while specific oil consumption decreased, and effective thermal efficiency of diesel engine increased.

Engine combustion control at low loads via fuel reactivity stratification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reitz, Rolf Deneys; Hanson, Reed M.; Splitter, Derek A.

A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustionmore » chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.« less

An investigation of fluid flow during induction stroke of a water analog model of an IC engine using an innovative optical velocimetry concept: LIPA

NASA Technical Reports Server (NTRS)

Stier, Bernd; Falco, R. E.

1994-01-01

Optical measurements on an axisymmetrical quartz component engine research model were made to evaluate the flow field encountered during induction. The measurement technique is LIPA (Laser Induced Photochemical Anemometry), a non-intrusive velocimetry concept that provides an investigator of fluid flow with a tool to attain planar information about three-dimensional velocity and vorticity vectors in a single measurement step. The goal of this investigation is to further develop this measurement technique and apply it to study the induction stroke of a water analog model of a four-stroke internal combustion engine. The research conducted in the water analog model is a fundamental scientific inquiry into the flow fields that develop in the induction stroke of an engine at idling engine speeds. As this is the first investigation of its kind using LIPA technique, our goal has been to quantify, in a preliminary manner, the flow field features that develop during the intake stroke. In the process a more comprehensive understanding of the flow field features was developed, and tied to the quantification. The study evaluated the flow field of the intake stroke by estimating fields of velocity and vorticity. On the basis of these data, information about fluid dynamics during induction at engine speeds of 10, 20, and 30 RPM (corresponding to 170, 340, and 510 RPM respectively, when air is the flowing medium) for three different valve lifts was obtained. The overall development of the flow field, its energy content (kinetic, fluctuation) for the different settings of the engine parameters, vorticity information, and cyclic variations have been quantified. These have been discussed in terms of mixing performance.

Numerical studies of the formation and destruction of vortices in a motored four-stroke piston-cylinder configuration

NASA Technical Reports Server (NTRS)

Schock, H. J.; Sosoka, D. J.; Ramos, J. I.

1983-01-01

A finite-difference procedure which solves the conservation equations of mass, momentum, and energy is used to investigate the effects of the compression ratio, engine speed, bore-to-stroke ratio, and air intake flow angle on the turbulent flow field within an axisymmetric piston-cylinder configuration. It is shown that in a four-stroke piston-cylinder configuration, the intake stroke is characterized by the formation of a piston vortex. The piston vortex is stretched during the intake stroke, and the head vortex has an almost constant diameter. For a 0-deg air intake flow angle, both vortices disappear by the end of the compression stroke; for an air intake flow angle of 45 deg, the flow field within the cylinder shows three elongated vortices which persist into the compression stroke and then break up and merge. It is also shown that larger bore-to-stroke ratios give rise to lower turbulent levels than smaller bore-to-stroke ratios and that the turbulent intensity is almost independent of the rpm.

Mathematical modeling of a four-stroke resonant engine for micro and mesoscale applications

NASA Astrophysics Data System (ADS)

Preetham, B. S.; Anderson, M.; Richards, C.

2014-12-01

In order to mitigate frictional and leakage losses in small scale engines, a compliant engine design is proposed in which the piston in cylinder arrangement is replaced by a flexible cavity. A physics-based nonlinear lumped-parameter model is derived to predict the performance of a prototype engine. The model showed that the engine performance depends on input parameters, such as heat input, heat loss, and load on the engine. A sample simulation for a reference engine with octane fuel/air ratio of 0.043 resulted in an indicated thermal efficiency of 41.2%. For a fixed fuel/air ratio, higher output power is obtained for smaller loads and vice-versa. The heat loss from the engine and the work done on the engine during the intake stroke are found to decrease the indicated thermal efficiency. The ratio of friction work to indicated work in the prototype engine is about 8%, which is smaller in comparison to the traditional reciprocating engines.

Increasing Reliability of a Small 2-Stroke Internal Combustion Engine for Dynamically Changing Altitudes

DTIC Science & Technology

2012-03-01

63 Figure 20: New 3 inch stainless pipe used as an intake manifold...speed range of 1,000 RPM to 4,000 RPM. Six electric heaters with a total capacity of 900 W were used to heat the inlet air allowing a maximum...of the engine volume and had a gummy diaphragm attached to reduce pressure and flow pulsations to allow for more accurate air flow measurements

Subsurface intake systems: Green choice for improving feed water quality at SWRO desalination plants, Jeddah, Saudi Arabia.

PubMed

Dehwah, Abdullah H A; Missimer, Thomas M

2016-01-01

An investigation of three seawater reverse osmosis facilities located along the shoreline of the Red Sea of Saudi Arabia that use well intake systems showed that the pumping-induced flow of raw seawater through a coastal aquifer significantly improves feed water quality. A comparison between the surface seawater and the discharge from the wells shows that turbidity, algae, bacteria, total organic carbon, most fractions of natural organic matter (NOM), and particulate and colloidal transparent exopolymer particles (TEP) have significant reductions in concentration. Nearly all of the algae, up to 99% of the bacteria, between 84 and 100% of the biopolymer fraction of NOM, and a high percentage of the TEP were removed during transport. The data suggest that the flowpath length and hydraulic retention time in the aquifer play the most important roles in removal of the organic matter. Since the collective concentrations of bacteria, biopolymers, and TEP in the intake seawater play important roles in the biofouling of SWRO membranes, the observed reductions suggest that the desalination facilities that use well intakes systems will have a potentially lower fouling rate compared to open-ocean intake systems. Furthermore, well intake system intakes also reduce the need for chemical usage during complex pretreatment systems required for operation of SWRO facilities using open-ocean intakes and reduce environmental impacts. Copyright © 2015 Elsevier Ltd. All rights reserved.

PROCEEDINGS OF A SYMPOSIUM ON COOLING WATER INTAKE TECHNOLOGIES TO PROTECT AQUATIC ORGANISMS

EPA Science Inventory

This Symposium brought together professionals from federal, state, and tribal regulatory agencies; industry; environmental organizations; engineering consulting firms; science and research organizations; academia; and other organizations concerned with mitigating harm to the aqua...

Control of the low-load region in partially premixed combustion

NASA Astrophysics Data System (ADS)

Ingesson, Gabriel; Yin, Lianhao; Johansson, Rolf; Tunestal, Per

2016-09-01

Partially premixed combustion (PPC) is a low temperature, direct-injection combustion concept that has shown to give promising emission levels and efficiencies over a wide operating range. In this concept, high EGR ratios, high octane-number fuels and early injection timings are used to slow down the auto-ignition reactions and to enhance the fuel and are mixing before the start of combustion. A drawback with this concept is the combustion stability in the low-load region where a high octane-number fuel might cause misfire and low combustion efficiency. This paper investigates the problem of low-load PPC controller design for increased engine efficiency. First, low-load PPC data, obtained from a multi-cylinder heavy- duty engine is presented. The data shows that combustion efficiency could be increased by using a pilot injection and that there is a non-linearity in the relation between injection and combustion timing. Furthermore, intake conditions should be set in order to avoid operating points with unfavourable global equivalence ratio and in-cylinder temperature combinations. Model predictive control simulations were used together with a calibrated engine model to find a gas-system controller that fulfilled this task. The findings are then summarized in a suggested engine controller design. Finally, an experimental performance evaluation of the suggested controller is presented.

DRIVE CYCLE EFFICIENCY AND EMISSIONS ESTIMATES FOR REACTIVITY CONTROLLED COMPRESSION IGNITION IN A MULTI-CYLINDER LIGHT-DUTY DIESEL ENGINE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Curran, Scott; Briggs, Thomas E; Cho, Kukwon

2011-01-01

In-cylinder blending of gasoline and diesel to achieve Reactivity Controlled Compression Ignition (RCCI) has been shown to reduce NOx and PM emissions while maintaining or improving brake thermal efficiency as compared to conventional diesel combustion (CDC). The RCCI concept has an advantage over many advanced combustion strategies in that by varying both the percent of premixed gasoline and EGR rate, stable combustion can be extended over more of the light-duty drive cycle load range. Changing the percent premixed gasoline changes the fuel reactivity stratification in the cylinder providing further control of combustion phasing and pressure rise rate than the usemore » of EGR alone. This paper examines the combustion and emissions performance of light-duty diesel engine using direct injected diesel fuel and port injected gasoline to carry out RCCI for steady-state engine conditions which are consistent with a light-duty drive cycle. A GM 1.9L four-cylinder engine with the stock compression ratio of 17.5:1, common rail diesel injection system, high-pressure EGR system and variable geometry turbocharger was modified to allow for port fuel injection with gasoline. Engine-out emissions, engine performance and combustion behavior for RCCI operation is compared against both CDC and a premixed charge compression ignition (PCCI) strategy which relies on high levels of EGR dilution. The effect of percent of premixed gasoline, EGR rate, boost level, intake mixture temperature, combustion phasing and pressure rise rate is investigated for RCCI combustion for the light-duty modal points. Engine-out emissions of NOx and PM were found to be considerably lower for RCCI operation as compared to CDC and PCCI, while HC and CO emissions were higher. Brake thermal efficiency was similar or higher for many of the modal conditions for RCCI operation. The emissions results are used to estimate hot-start FTP-75 emissions levels with RCCI and are compared against CDC and PCCI modes.« less

Stroke and Nutrition: A Review of Studies

PubMed Central

Foroughi, Mehdi; Akhavanzanjani, Mohsen; Maghsoudi, Zahra; Ghiasvand, Reza; Khorvash, Fariborz; Askari, Gholamreza

2013-01-01

Background: Stroke is one of the leading causes of death and certainly the major cause of disability in the world. Diet and nutrient has an effective role in prevention and control of the risk of stroke. The aim of this study was to review the studies on the relationship between dietary intake and stroke incidence. Methods: In this study, the terms of “Fat”, “cholesterol”, “antioxidant”, “vitamins”, “salt”, “potassium”, “calcium”, “carbohydrate”, “vegetables”, “fruits”, “meat”, “tea”, “whole grains”, “sugar-sweetened beverages”, “Mediterranean diet”, “dietary approaches to stop hypertension diet (DASH diet)”, “Western diet”, and “stroke” were searched in Pubmed search engine. The observational studies, cohort studies, clinical trial studies, systemic review, and meta-analysis reviews are also included in this study. Results: The study revealed that adherence to theimprovements in nutrition and diet canreducethe incidence ofstroke. Higher antioxidant, vitamins, potassium, calcium, vegetables, fruits, whole grain intake, and adherence to the Mediterranean dietor DASH diet can lower stroke incidence. Conclusions: Adherence to Mediterranean diet or DASH diet and increasing the consumption of antioxidant, vitamins, potassium, calcium food sources, vegetables, fruits, and whole grains intake can lower the risk of stroke. Healthy diet is effective in reducing risk of stroke, however, more studies need to be carried out in this area. PMID:23776719

View of steel flume (Irving intake system) that is covered ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of steel flume (Irving intake system) that is covered with old flume stock, flattened to protect from debris, animals and daylight, and is supported by wood trestles, as it continues downhill toward the Irving Powerhouse. Truck in photo provides scale. Looking north - Childs-Irving Hydroelectric Project, Irving System, Intake System, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

Performance and Durability of a Generator Set CI Engine using Synthetic and Petroleum Based Fuels for Military Applications

DTIC Science & Technology

2009-07-27

viable; however, better understanding of the fundamental effects of alternative fuels on engine operation is required before control strategies can be...calibrated for Diesel #2 fuel. This was not altered throughout the testing. The intake is a turbocharged -aspirated engine with a compression ratio of... Fundamentals . New York: McGraw‐ [ Hill, 1988    [2]   Noble P, McMillan D, Dabell M. Development of a Diesel‐Powered, Heavy Lift,  Amphibious  Air‐Cushion

After-Test Engine Inspection of U.S. Army Administrative and Light-Tactical Vehicles Operated on Gasohol and Unleaded Gasoline.

DTIC Science & Technology

1983-02-01

Force 76-84 @ 1.82 (338)-(374)@(46.23) Intake 174.0 71 220.3 215-237 @ 1.39 88 85 81 95-105 @ I 13/16" (774) (316) (980) (956)-(1054)@ (391) (378) (360...Mfg. Specs per Veh. Gasohol Gasoline Station Chrysler V-8, 318 CID 07121303 5 16 31 -- Ft. Belvoir 07090311 6 16 38 -- Ft. Belvoir 03223146 5 16...TABLE 6. CRC RATINGS FOR TEST ENGINES FROM FT. BELVOIR, VA Type Engine Chrysler V-8, 318 CID Jeep, 4 Cylinder, 140 CID Serial Number 07121303 07090311

Principle Findings from Development of a Recirculated Exhaust Gas Intake Sensor (REGIS) Enabling Cost-Effective Fuel Efficiency Improvement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schnabel, Claus

Kick-off of the Bosch scope of work for the REGIS project started in October 2012. The primary work-packages included in the Bosch scope of work were the following: overall project management, development of the EGR sensor (design of sensor element, design of protection tube, and design of mounting orientation), development of EGR system control strategy, build-up of prototype sensors, evaluation of system performance with the new sensor and the new control strategy, long-term durability testing, and development of a 2nd generation sensor concept for continued technology development after the REGIS project. The University of Clemson was a partner with Boschmore » in the REGIS project. The Clemson scope of work for the REGIS project started in June 2013. The primary work-packages included in the Clemson scope of work were the following: development of EGR system control strategy, and evaluation of system performance with the new sensor and new control strategy. This project was split into phase I, phase II and phase III. Phase I work was completed by the end of June 2014 and included the following primary work packages: development of sensor technical requirements, assembly of engine testbench at Clemson, design concept for sensor housing, connector, and mounting orientation, build-up of EGR flow test benches at Bosch, and build-up of first sensor prototypes. Phase II work was completed by the end of June 2015 and included the following primary work pack ages: development of an optimizing function and demonstration of robustness of sensor, system control strategy implementation and initial validation, completion of engine in the loop testing of developed control algorithm, completion of sensor testing including characteristic line, synthetic gas test stand, and pressure dependency characterization, demonstration of benefits of control w/o sensing via simulation, development of 2nd generation sensor concept. Notable technical achievements from phase II were the following: publication of two new technical papers by Clemson detailing the control strategies used for the EGR system control. The two papers was published in the 2016 SAE World Congress in April 2016. The titles of each paper are, “Physics-Based Exhaust Pressure and Temperature Estimation for Low Pressure EGR Control in Turbocharged Gasoline Engines,” by K. Siokos, and “A Control Algorithm for Low Pressure – EGR Systems using a Smith Predictor with Intake Oxygen Sensor Feedback”, by R. Koli. All phase III work packages have been completed. The primary work packages in phase III were the following: completion of long-term sensor durability testing, final demonstration of benefits of EGR control w/o sensing, final decision of the second generation sensor development path.« less

View of Diversion Dam and Flume Intake of the Childs ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Diversion Dam and Flume Intake of the Childs System at the Irving Powerhouse. Looking northwest - Childs-Irving Hydroelectric Project, Childs System, Flume Intake & Forebay, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

GM biofortified crops: potential effects on targeting the micronutrient intake gap in human populations.

PubMed

De Steur, Hans; Mehta, Saurabh; Gellynck, Xavier; Finkelstein, Julia L

2017-04-01

Genetic engineering has been successfully applied to increase micronutrient content in staple crops. Nutrition evidence is key to ensure scale-up and successful implementation. Unlike conventional plant breeding efforts, research on the efficacy or effectiveness of GM biofortified crops on nutritional status in human populations is lacking. This review reports on the potential role of GM biofortified crops in closing the micronutrient gap - increasing the dietary intake of micronutrients in human populations. To date, one clinical trial in the United States reported a high bio-conversion rate of β-carotene in Golden Rice, and potential effects of GM biofortified crop consumption on dietary intake and nutritional outcomes are promising. However, further research needs to confirm the ex ante assessments in target regions. Copyright © 2017. Published by Elsevier Ltd.

Effect of Intake Air Filter Condition on Light-Duty Gasoline Vehicles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomas, John F; Huff, Shean P; West, Brian H

2012-01-01

Proper maintenance can help vehicles perform as designed, positively affecting fuel economy, emissions, and the overall drivability. This effort investigates the effect of one maintenance factor, intake air filter replacement, with primary focus on vehicle fuel economy, but also examining emissions and performance. Older studies, dealing with carbureted gasoline vehicles, have indicated that replacing a clogged or dirty air filter can improve vehicle fuel economy and conversely that a dirty air filter can be significantly detrimental to fuel economy. The effect of clogged air filters on the fuel economy, acceleration and emissions of five gasoline fueled vehicles is examined. Fourmore » of these were modern vehicles, featuring closed-loop control and ranging in model year from 2003 to 2007. Three vehicles were powered by naturally aspirated, port fuel injection (PFI) engines of differing size and cylinder configuration: an inline 4, a V6 and a V8. A turbocharged inline 4-cylinder gasoline direct injection (GDI) engine powered vehicle was the fourth modern gasoline vehicle tested. A vintage 1972 vehicle equipped with a carburetor (open-loop control) was also examined. Results reveal insignificant fuel economy and emissions sensitivity of modern vehicles to air filter condition, but measureable effects on the 1972 vehicle. All vehicles experienced a measured acceleration performance penalty with clogged intake air filters.« less

A study of optimum cowl shapes and flow port locations for minimum drag with effective engine cooling, volume 2

NASA Technical Reports Server (NTRS)

Fox, S. R.; Smetana, F. O.

1980-01-01

The listings, user's instructions, sample inputs, and sample outputs of two computer programs which are especially useful in obtaining an approximate solution of the viscous flow over an arbitrary nonlifting three dimensional body are provided. The first program performs a potential flow solution by a well known panel method and readjusts this initial solution to account for the effects of the boundary layer displacement thickness, a nonuniform but unidirectional onset flow field, and the presence of air intakes and exhausts. The second program is effectually a geometry package which allows the user to change or refine the shape of a body to satisfy particular needs without a significant amount of human intervention. An effort to reduce the cruise drag of light aircraft through an analytical study of the contributions to the drag arising from the engine cowl shape and the foward fuselage area and also that resulting from the cooling air mass flowing through intake and exhaust sites on the nacelle is presented. The programs may be effectively used to determine the appropriate body modifications or flow port locations to reduce the cruise drag as well as to provide sufficient air flow for cooling the engine.

Army Ground Vehicles and Current/Future Emission Standards

DTIC Science & Technology

2008-10-23

cooler’ combustion temperatures • Two stages of turbocharging (single stage for smaller displacement engines) • Additional charge air cooling...Recirculate and cool exhaust gas up or downstream of turbine ( turbocharger ) ; require back pressure restriction and/or intake throttle to flow

Instituting a filtration/pressurization system to reduce dust concentrations in a control room at a mineral processing plant

PubMed Central

Noll, J.; Cecala, A.; Hummer, J.

2016-01-01

The National Institute for Occupational Safety and Health has observed that many control rooms and operator compartments in the U.S. mining industry do not have filtration systems capable of maintaining low dust concentrations in these areas. In this study at a mineral processing plant, to reduce respirable dust concentrations in a control room that had no cleaning system for intake air, a filtration and pressurization system originally designed for enclosed cabs was modified and installed. This system was composed of two filtering units: one to filter outside air and one to filter and recirculate the air inside the control room. Eighty-seven percent of submicrometer particles were reduced by the system under static conditions. This means that greater than 87 percent of respirable dust particles should be reduced as the particle-size distribution of respirable dust particles is greater than that of submicrometer particles, and filtration systems usually are more efficient in capturing the larger particles. A positive pressure near 0.02 inches of water gauge was produced, which is an important component of an effective system and minimizes the entry of particles, such as dust, into the room. The intake airflow was around 118 cfm, greater than the airflow suggested by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) for acceptable indoor air quality. After one year, the loading of the filter caused the airflow to decrease to 80 cfm, which still produces acceptable indoor air quality. Due to the loading of the filters, the reduction efficiency for submicrometer particles under static conditions increased to 94 percent from 87 percent. PMID:26834293

Defense Small Business Innovation Research Program (SBIR). Volume 3. Air Force Abstracts of Phase 1 Awards 1992

DTIC Science & Technology

1992-01-01

boost plenum which houses the camshaft . The compressed mixture is metered by a throttle to intake valves of the engine. The engine is constructed from...difficulties associated with a time-tagged fault tree . In particular, recent work indicates that the multi-layer perception architecture can give good fdi...Abstract: In the past decade, wastepaper recycling has gained a wider acceptance. Depletion of tree stocks, waste water treatment demands and

In-cylinder flows of a motored four-stroke engine with flat-crown and slightly concave-crown pistons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, R.F.; Yang, H.S.; Yeh, C.-N.

2008-04-15

The temporal and spatial evolution processes of the in-cylinder flow structures and turbulence intensities in the symmetry and offset planes of a motored four-valve, four-stroke engine during the intake and compression strokes are diagnosed by using a particle image velocimeter. Two pistons of different crown shapes (flat-crown and slightly concave-crown pistons) are studied. The inception, establishment, and evolution of the tumbling vortical flow structures during the intake and compression strokes are clearly depicted. Quantitative strengths of the rotating vortical flow motions are presented by a dimensionless parameter, the tumble ratio, which can represent the mean angular velocity of the vorticesmore » in the target plane. The turbulence intensity of the in-cylinder flow is also calculated by using the measured time-varying velocity data. The results show that the flat-crown piston induces higher bulk-averaged tumble ratio and turbulence intensity than the slightly concave-crown piston does because the tumble ratio and turbulence generated by the flat-crown piston in the offset planes during the compression stroke are particularly large. The engine with the flat-crown piston also presents larger torque and power outputs and lower hydrocarbon emission than that with the slightly concave-crown piston. This might be caused by the enhanced combustion in the engine cylinder due to the stronger tumble ratio and turbulence intensity. (author)« less

Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

NASA Astrophysics Data System (ADS)

Heath, Garvin A.; Nazaroff, William W.

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164-7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants—PM 2.5, NO x and formaldehyde—directly emitted by five DG technologies—natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric energy delivered to the place of use. We find that the central tendency of IDER is much greater for almost every DG technology evaluated than for existing CS facilities in California.

Inhibition of IKKβ Reduces Ethanol Consumption in C57BL/6J Mice.

PubMed

Truitt, Jay M; Blednov, Yuri A; Benavidez, Jillian M; Black, Mendy; Ponomareva, Olga; Law, Jade; Merriman, Morgan; Horani, Sami; Jameson, Kelly; Lasek, Amy W; Harris, R Adron; Mayfield, R Dayne

2016-01-01

Proinflammatory pathways in neuronal and non-neuronal cells are implicated in the acute and chronic effects of alcohol exposure in animal models and humans. The nuclear factor-κB (NF-κB) family of DNA transcription factors plays important roles in inflammatory diseases. The kinase IKKβ mediates the phosphorylation and subsequent proteasomal degradation of cytosolic protein inhibitors of NF-κB, leading to activation of NF-κB. The role of IKKβ as a potential regulator of excessive alcohol drinking had not previously been investigated. Based on previous findings that the overactivation of innate immune/inflammatory signaling promotes ethanol consumption, we hypothesized that inhibiting IKKβ would limit/decrease drinking by preventing the activation of NF-κB. We studied the systemic effects of two pharmacological inhibitors of IKKβ, TPCA-1 and sulfasalazine, on ethanol intake using continuous- and limited-access, two-bottle choice drinking tests in C57BL/6J mice. In both tests, TPCA-1 and sulfasalazine reduced ethanol intake and preference without changing total fluid intake or sweet taste preference. A virus expressing Cre recombinase was injected into the nucleus accumbens and central amygdala to selectively knock down IKKβ in mice genetically engineered with a conditional Ikkb deletion ( Ikkb F/F ). Although IKKβ was inhibited to some extent in astrocytes and microglia, neurons were a primary cellular target. Deletion of IKKβ in either brain region reduced ethanol intake and preference in the continuous access two-bottle choice test without altering the preference for sucrose. Pharmacological and genetic inhibition of IKKβ decreased voluntary ethanol consumption, providing initial support for IKKβ as a potential therapeutic target for alcohol abuse.

40 CFR 1065.280 - Paramagnetic and magnetopneumatic O2 detection analyzers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments O2 Measurements § 1065... diluted exhaust for batch or continuous sampling. You may use O2 measurements with intake air or fuel flow.... 15, 2011] Air-to-Fuel Ratio Measurements ...

40 CFR 1065.280 - Paramagnetic and magnetopneumatic O2 detection analyzers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments O2 Measurements § 1065... diluted exhaust for batch or continuous sampling. You may use O2 measurements with intake air or fuel flow.... 15, 2011] Air-to-Fuel Ratio Measurements ...

A two-dimensional numerical study of the flow inside the combustion chambers of a motored rotary engine

NASA Technical Reports Server (NTRS)

Shih, T. I. P.; Yang, S. L.; Schock, H. J.

1986-01-01

A numerical study was performed to investigate the unsteady, multidimensional flow inside the combustion chambers of an idealized, two-dimensional, rotary engine under motored conditions. The numerical study was based on the time-dependent, two-dimensional, density-weighted, ensemble-averaged conservation equations of mass, species, momentum, and total energy valid for two-component ideal gas mixtures. The ensemble-averaged conservation equations were closed by a K-epsilon model of turbulence. This K-epsilon model of turbulence was modified to account for some of the effects of compressibility, streamline curvature, low-Reynolds number, and preferential stress dissipation. Numerical solutions to the conservation equations were obtained by the highly efficient implicit-factored method of Beam and Warming. The grid system needed to obtain solutions were generated by an algebraic grid generation technique based on transfinite interpolation. Results of the numerical study are presented in graphical form illustrating the flow patterns during intake, compression, gaseous fuel injection, expansion, and exhaust.

A two-dimensional numerical study of the flow inside the combustion chamber of a motored rotary engine

NASA Technical Reports Server (NTRS)

Shih, T. I-P.; Yang, S. L.; Schock, H. J.

1986-01-01

A numerical study was performed to investigate the unsteady, multidimensional flow inside the combustion chambers of an idealized, two-dimensional, rotary engine under motored conditions. The numerical study was based on the time-dependent, two-dimensional, density-weighted, ensemble-averaged conservation equations of mass, species, momentum, and total energy valid for two-component ideal gas mixtures. The ensemble-averaged conservation equations were closed by a K-epsilon model of turbulence. This K-epsilon model of turbulence was modified to account for some of the effects of compressibility, streamline curvature, low-Reynolds number, and preferential stress dissipation. Numerical solutions to the conservation equations were obtained by the highly efficient implicit-factored method of Beam and Warming. The grid system needed to obtain solutions were generated by an algebraic grid generation technique based on transfinite interpolation. Results of the numerical study are presented in graphical form illustrating the flow patterns during intake, compression, gaseous fuel injection, expansion, and exhaust.

How strongly does appetite counter weight loss? Quantification of the feedback control of human energy intake

PubMed Central

Polidori, David; Sanghvi, Arjun; Seeley, Randy; Hall, Kevin D.

2016-01-01

Objective To quantify the feedback control of energy intake in response to long-term covert manipulation of energy balance in free-living humans. Methods We used a validated mathematical method to calculate energy intake changes during a 52 week placebo-controlled trial in 153 patients treated with canagliflozin, a sodium glucose co-transporter inhibitor that increases urinary glucose excretion thereby resulting in weight loss without patients being directly aware of the energy deficit. We analyzed the relationship between the body weight time course and the calculated energy intake changes using principles from engineering control theory. Results We discovered that weight loss leads to a proportional increase in appetite resulting in eating above baseline by ~100 kcal/day per kg of lost weight – an amount more than 3-fold larger than the corresponding energy expenditure adaptations. Conclusions While energy expenditure adaptations are often thought to be the main reason for slowing of weight loss and subsequent regain, feedback control of energy intake plays an even larger role and helps explain why long-term maintenance of a reduced body weight is so difficult. PMID:27804272

Effect of renin-angiotensin system on sodium intake.

PubMed Central

Chiaraviglio, E

1976-01-01

1. Water and saline intake was measured in rats depleted of Na by I.P. dialysis. Na intake was prevented 180 min but not 60-90 min after bilateral nephrectomy. Unilateral nephrectomy as well as ureteral ligature had no effect on Na intake. 2. Renin (3u.) injected I.P. re-established the Na appetite abolished by nephrectomy. 3. Angiotensin I (5 ng) or II (5-40 ng) injected into the 3rd ventricle, also restored the Na intake and this effect was dose-dependent. 4. The angiotensin converting-enzyme inhibitor Sq 20,881 (1 mg/kg) inhibited the effect of AI but not that of AII in restoring Na intake. 5. It is concluded that the kidneys might play a role in the regulation of Na intake through the renin-angiotensin system. PMID:1255521

STEAM PLANT, TRA609. SECTION A SHOWS FEATURES OF NORTH/SOUTH AXIS: ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

STEAM PLANT, TRA-609. SECTION A SHOWS FEATURES OF NORTH/SOUTH AXIS: STEAM GENERATOR AND CATWALK, STACK, DEGREASER FEED WATER HEATER IN PENTHOUSE, MEZZANINE, SURGE TANK PIT (BELOW GROUND LEVEL). UTILITY ROOM SHOWS DIESEL ENGINE GENERATORS, AIR TANKS, STARTING AIR COMPRESSORS. OUTSIDE SOUTH END ARE EXHAUST MUFFLER, AIR INTAKE OIL FILTER, RADIATOR COOLING UNIT, AIR SURGE TANK. SECTION B CROSSES WEST TO EAST NEAR SOUTH END OF BUILDING TO SHOW ARRANGEMENT OF DIESEL ENGINE GENERATOR, AIR DRIER, AFTER COOLER, AIR COMPRESSOR, AND BLOWDOWN TANK. BLAW-KNOX 3150-9-2, 6/1950. INL INDEX NO. 431-0609-00-098-100018, REV. 3. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Study of materials used for the thermal protection of the intake system for internal combustion engines

NASA Astrophysics Data System (ADS)

Birtok-Băneasă, C.; Raţiu, S.; Puţan, V.; Josan, A.

2018-01-01

The present paper focuses on calculation of thermal conductivity for a new materials developed by the authors, using the heat flux plate method. This experimental method consists in placing the sample of the new material in a calorimetric chamber and heating from underside. As the heat flux which passes through the sample material is constant and knowing the values of the temperatures for the both sides of sample, the sample material thermal conductivity is determined. Six types of different materials were tested. Based on the experimental data, the values of the thermal conductivity according to the material and the average temperature were calculated and plotted.

The two-stroke poppet valve engine. Part 2: Numerical investigations of intake and exhaust flow behaviour

NASA Astrophysics Data System (ADS)

Kamili Zahidi, M.; Razali Hanipah, M.

2017-10-01

A two-stroke poppet valve engine is developed to overcome the common problems in conventional two-stroke engine designs. However, replacing piston control port with poppet valve will resulted different flow behaviour. This paper presents the model and simulation result of three-dimensional (3D) port flow investigation of a two-stroke poppet valve engine. The objective of the investigation is to conduct a numerical investigation on port flow performance of two-stroke poppet valve engine and compare the results obtained from the experimental investigation. The model is to be used for the future numerical study of the engine. The volume flow rate results have been compared with the results obtained experimentally as presented in first part of this paper. The model has shown good agreement in terms of the flow rate at initial and final valve lifts but reduced by about 50% during half-lift region.

Comparative study of oxihydrogen injection in turbocharged compression ignition engines

NASA Astrophysics Data System (ADS)

Barna, L.; Lelea, D.

2018-01-01

This document proposes for analysis, comparative study of the turbocharged, compression-ignition engine, equipped with EGR valve, operation in case the injection in intake manifold thereof a maximum flow rate of 1l/min oxyhydrogen resulted of water electrolysis, at two different injection pressures, namely 100 Pa and 3000 Pa, from the point of view of flue gas opacity. We found a substantial reduction of flue gas opacity in both cases compared to conventional diesel operation, but in different proportions.

Correlation of Mixture Temperature Data Obtained from Bare Intake-manifold Thermocouples

NASA Technical Reports Server (NTRS)

White, H. Jack; Gammon, Goldie L

1946-01-01

A relatively simple equation has been found to express with fair accuracy, variation in manifold-charge temperature with charge in engine operating conditions. This equation and associated curves have been checked by multi cylinder-engine data, both test stand and flight, over a wide range of operating conditions. Average mixture temperatures, predicted by the equations of this report, agree reasonably well with results within the same range of carburetor-air temperatures from laboratories and test stands other than the NACA.

Particle image velocimetry investigation of a finite amplitude pressure wave

NASA Astrophysics Data System (ADS)

Thornhill, D.; Currie, T.; Fleck, R.; Chatfield, G.

2006-03-01

Particle image velocimetry is used to study the motion of gas within a duct subject to the passage of a finite amplitude pressure wave. The wave is representative of the pressure waves found in the exhaust systems of internal combustion engines. Gas particles are accelerated from stationary to 150 m/s and then back to stationary in 8 ms. It is demonstrated that gas particles at the head of the wave travel at the same velocity across the duct cross section at a given point in time. Towards the tail of the wave viscous effects are plainly evident causing the flow profile to tend towards parabolic. However, the instantaneous mean particle velocity across the section is shown to match well with the velocity calculated from a corresponding measured pressure history using 1D gas dynamic theory. The measured pressure history at a point in the duct was acquired using a high speed pressure transducer of the type typically used for engine research in intake and exhaust systems. It is demonstrated that these are unable to follow the rapid changes in pressure accurately and that they are prone to resonate under certain circumstances.

Experimental Investigation of Actuators for Flow Control in Inlet Ducts

NASA Astrophysics Data System (ADS)

Vaccaro, John; Elimelech, Yossef; Amitay, Michael

2010-11-01

Attractive to aircraft designers are compact inlets, which implement curved flow paths to the compressor face. These curved flow paths could be employed for multiple reasons. One of which is to connect the air intake to the engine embedded in the aircraft body. A compromise must be made between the compactness of the inlet and its aerodynamic performance. The aerodynamic purpose of inlets is to decelerate the oncoming flow before reaching the engine while minimizing total pressure loss, unsteadiness and distortion. Low length-to-diameter ratio inlets have a high degree of curvature, which inevitably causes flow separation and secondary flows. Currently, the length of the propulsion system is constraining the overall size of Unmanned Air Vehicles (UAVs), thus, smaller more efficient aircrafts could be realized if the propulsion system could be shortened. Therefore, active flow control is studied in a compact (L/D=1.5) inlet to improve performance metrics. Actuation from a spanwise varying coanda type ejector actuator and a hybrid coanda type ejector / vortex generator jet actuator is investigated. Special attention will be given to the pressure recovery at the AIP along with unsteady pressure signatures along the inlet surface and at the AIP.

Tuned intake air inlet for a rotary engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corbett, W.D.; Sheaffer, B.L.

This patent describes, in a rotary internal combustion engine, an improved assembly for providing a balanced flow of combustion air to the fuel supply inlet. It comprises: a plenum chamber attached to the engine block, the plenum chamber including an air inlet adapted to receive air from the cooling air exit passage and an air outlet for the discharge of air; and an outlet conduit connecting the air outlet and the fuel supply inlet. The conduit disposed to partially surround the plenum chamber to provide a conduit length substantially greater than the distance from the cooling air exit passage totmore » he fuel supply inlet.« less

Reproducibility of ad libitum energy intake with the use of a computerized vending machine system123

PubMed Central

Votruba, Susanne B; Franks, Paul W; Krakoff, Jonathan; Salbe, Arline D

2010-01-01

Background: Accurate assessment of energy intake is difficult but critical for the evaluation of eating behavior and intervention effects. Consequently, methods to assess ad libitum energy intake under controlled conditions have been developed. Objective: Our objective was to evaluate the reproducibility of ad libitum energy intake with the use of a computerized vending machine system. Design: Twelve individuals (mean ± SD: 36 ± 8 y old; 41 ± 8% body fat) consumed a weight-maintaining diet for 3 d; subsequently, they self-selected all food with the use of a computerized vending machine system for an additional 3 d. Mean daily energy intake was calculated from the actual weight of foods consumed and expressed as a percentage of weight-maintenance energy needs (%WMEN). Subjects repeated the study multiple times during 2 y. The within-person reproducibility of energy intake was determined through the calculation of the intraclass correlation coefficients (ICCs) between visits. Results: Daily energy intake for all subjects was 5020 ± 1753 kcal during visit 1 and 4855 ± 1615 kcal during visit 2. There were no significant associations between energy intake and body weight, body mass index, or percentage body fat while subjects used the vending machines, which indicates that intake was not driven by body size or need. Despite overconsumption (%WMEN = 181 ± 57%), the reproducibility of intake between visits, whether expressed as daily energy intake (ICC = 0.90), %WMEN (ICC = 0.86), weight of food consumed (ICC = 0.87), or fat intake (g/d; ICC = 0.87), was highly significant (P < 0.0001). Conclusion: Although ad libitum energy intake exceeded %WMEN, the within-person reliability of this intake across multiple visits was high, which makes this a reproducible method for the measurement of ad libitum intake in subjects who reside in a research unit. This trial was registered at clinicaltrials.gov as NCT00342732. PMID:19923376

Selective NOx Recirculation for Stationary Lean-Burn Natural Gas Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nigel N. Clark

Nitric oxide (NO) and nitrogen dioxide (NO2) generated by internal combustion (IC) engines are implicated in adverse environmental and health effects. Even though lean-burn natural gas engines have traditionally emitted lower oxides of nitrogen (NOx) emissions compared to their diesel counterparts, natural gas engines are being further challenged to reduce NOx emissions to 0.1 g/bhp-hr. The Selective NOx Recirculation (SNR) approach for NOx reduction involves cooling the engine exhaust gas and then adsorbing the NOx from the exhaust stream, followed by the periodic desorption of NOx. By sending the desorbed NOx back into the intake and through the engine, amore » percentage of the NOx can be decomposed during the combustion process. SNR technology has the support of the Department of Energy (DOE), under the Advanced Reciprocating Engine Systems (ARES) program to reduce NOx emissions to under 0.1 g/bhp-hr from stationary natural gas engines by 2010. The NO decomposition phenomenon was studied using two Cummins L10G natural gas fueled spark-ignited (SI) engines in three experimental campaigns. It was observed that the air/fuel ratio ({lambda}), injected NO quantity, added exhaust gas recirculation (EGR) percentage, and engine operating points affected NOx decomposition rates within the engine. Chemical kinetic model predictions using the software package CHEMKIN were performed to relate the experimental data with established rate and equilibrium models. The model was used to predict NO decomposition during lean-burn, stoichiometric burn, and slightly rich-burn cases with added EGR. NOx decomposition rates were estimated from the model to be from 35 to 42% for the lean-burn cases and from 50 to 70% for the rich-burn cases. The modeling results provided an insight as to how to maximize NOx decomposition rates for the experimental engine. Results from this experiment along with chemical kinetic modeling solutions prompted the investigation of rich-burn operating conditions, with added EGR to prevent preignition. It was observed that the relative air/fuel ratio, injected NO quantity, added EGR fraction, and engine operating points affected the NO decomposition rates. While operating under these modified conditions, the highest NO decomposition rate of 92% was observed. In-cylinder pressure data gathered during the experiments showed minimum deviation from peak pressure as a result of NO injections into the engine. A NOx adsorption system, from Sorbent Technologies, Inc., was integrated with the Cummins engine, comprised a NOx adsorbent chamber, heat exchanger, demister, and a hot air blower. Data were gathered to show the possibility of NOx adsorption from the engine exhaust, and desorption of NOx from the sorbent material. In order to quantify the NOx adsorption/desorption characteristics of the sorbent material, a benchtop adsorption system was constructed. The temperature of this apparatus was controlled while data were gathered on the characteristics of the sorbent material for development of a system model. A simplified linear driving force model was developed to predict NOx adsorption into the sorbent material as cooled exhaust passed over fresh sorbent material. A mass heat transfer analysis was conducted to analyze the possibility of using hot exhaust gas for the desorption process. It was found in the adsorption studies, and through literature review, that NO adsorption was poor when the carrier gas was nitrogen, but that NO in the presence of oxygen was adsorbed at levels exceeding 1% by mass of the sorbent. From the three experimental campaigns, chemical kinetic modeling analysis, and the scaled benchtop NOx adsorption system, an overall SNR system model was developed. An economic analysis was completed, and showed that the system was impractical in cost for small engines, but that economies of scale favored the technology.« less

40 CFR 1033.505 - Ambient conditions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air from...

40 CFR 1033.505 - Ambient conditions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air from...

40 CFR 1033.505 - Ambient conditions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air from...

40 CFR 1033.505 - Ambient conditions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air from...

40 CFR 1033.505 - Ambient conditions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 1033.505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS... presumed that combustion air will be drawn from the ambient air. Thus, the ambient temperature limits of this paragraph (a) apply for intake air upstream of the engine. If you do not draw combustion air from...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szybist, James P.; Splitter, Derek A.

The octane sensitivity (S), defined as the difference between the Research Octane Number (RON) and the Motor Octane Number (MON), is of increasing interest in spark ignition (SI) engines because of its relevance to knock resistance at boosted high load conditions. In this study, three fuels with nearly constant RON (99.2-100) and varying S (S = 0, 6.5, and 12) are operated at the knock limited spark advance (KLSA) at nominal engine loads of 10, 15, and 20 bar IMEP in a single cylinder SI engine with side-mount direct injection fueling, at λ =1 stoichiometry. At each load condition, themore » intake manifold temperature is swept from 35 °C to 95 °C to alter the temperature and pressure history of the charge. Results show that at the 10 bar IMEP condition, knock resistance is inversely proportional to fuel S where the S=0 fuel is the most knock resist, but as load increases the trend reverses and knock resistance becomes proportional to fuel S, and the S=12 fuel is the most knock resistant. The reversal of knock resistance as a function of S with load it is attributed to changing fuel ignition delay, as bulk gas intermediate temperature heat release (ITHR) is observed for the S = 0 several crank angles prior to the spark command and ITHR magnitude is a function of increasing intake temperature. As intake temperature continued to increase, the S=0 fuel transitioned from ITHR to low-temperature heat release (LTHR) prior to the spark event. At the highest load and intake temperature, 95 C, the S=0 fuel exhibits distinct LTHR and negative temperature coefficient (NTC), and the intermediate S value fuel (S=6.5) exhibited distinct ITHR behavior several crank angles prior to the spark command. However, for the tested conditions, the S=12 fuel exhibits neither ITHR nor LTHR. To understand the measured trends, chemical kinetic modeling is used to elucidate the fuel specific dependencies on in-cylinder temperature and pressure history. Lastly, the bulk gas composition change that occurs for fuels and conditions exhibiting ITHR and LTHR is analyzed in the modeling, including their implications on flame speed and combustion stability at late phasing. Furthermore, the combined findings illustrate the commonality and utility of fuel S, ITHR, LTHR, and NTC across a wide range of conditions, and the associated implications of fuel S in highly boosted modern GDI SI engines relative to the RON and MON tests.« less

Development and applications of various optimization algorithms for diesel engine combustion and emissions optimization

NASA Astrophysics Data System (ADS)

Ogren, Ryan M.

For this work, Hybrid PSO-GA and Artificial Bee Colony Optimization (ABC) algorithms are applied to the optimization of experimental diesel engine performance, to meet Environmental Protection Agency, off-road, diesel engine standards. This work is the first to apply ABC optimization to experimental engine testing. All trials were conducted at partial load on a four-cylinder, turbocharged, John Deere engine using neat-Biodiesel for PSO-GA and regular pump diesel for ABC. Key variables were altered throughout the experiments, including, fuel pressure, intake gas temperature, exhaust gas recirculation flow, fuel injection quantity for two injections, pilot injection timing and main injection timing. Both forms of optimization proved effective for optimizing engine operation. The PSO-GA hybrid was able to find a superior solution to that of ABC within fewer engine runs. Both solutions call for high exhaust gas recirculation to reduce oxide of nitrogen (NOx) emissions while also moving pilot and main fuel injections to near top dead center for improved tradeoffs between NOx and particulate matter.

Liquid sprays and flow studies in the direct-injection diesel engine under motored conditions

NASA Technical Reports Server (NTRS)

Nguyen, Hung Lee; Carpenter, Mark H.; Ramos, Juan I.; Schock, Harold J.; Stegeman, James D.

1988-01-01

A two dimensional, implicit finite difference method of the control volume variety, a two equation model of turbulence, and a discrete droplet model were used to study the flow field, turbulence levels, fuel penetration, vaporization, and mixing in diesel engine environments. The model was also used to study the effects of engine speed, injection angle, spray cone angle, droplet distribution, and intake swirl angle on the flow field, spray penetration and vaporization, and turbulence in motored two-stroke diesel engines. It is shown that there are optimum conditions for injection, which depend on droplet distribution, swirl, spray cone angle, and injection angle. The optimum conditions result in good spray penetration and vaporization and in good fuel mixing. The calculation presented clearly indicates that internal combustion engine models can be used to assess, at least qualitatively, the effects of injection characteristics and engine operating conditions on the flow field and on the spray penetration and vaporization in diesel engines.

Does a new steam meal catering system meet patient requirements in hospital?

PubMed

Hickson, M; Fearnley, L; Thomas, J; Evans, S

2007-10-01

It has been consistently observed that a significant proportion of hospital inpatients are malnourished and many actually develop malnutrition in hospital. The NHS provides over 300 million meals each year at a cost of pound 500 million, yet there is relatively little research evaluating how well different catering systems provide for the needs of hospital inpatients. The aim of the study was to: (i) evaluate whether a new steam meal catering system (Steamplicity) enables patients in theory to meet their energy requirements in hospital and (ii) compare energy and protein intake using Steamplicity with a traditional bulk cook-chill system. Patients not at nutritional risk had their food intake at one lunchtime assessed. Energy intake was compared with the patients' energy requirements and energy and protein intake were compared with previous data from a bulk system. Fifty-seven patients had a median daily energy requirement of 7648 kJ (1821 kcal) [inter-quartile range (IQR): 6854-9164 kJ]. Assuming 30% [2293 kJ (546 kcal)] should be supplied by the lunch meal the average intake of 1369 kJ (326 kcal) fell short by 40%. Patients served meals from Steamplicity ate less energy [1369 kJ versus 1562 kJ (326 kcal versus 372 kcal) P = 0.04] but similar protein (18 g versus 19 g P = 0.34) to the bulk system. The largest difference was the energy provided by the dessert since the bulk system served more hot high-calorie desserts. Patient intakes did not meet their estimated requirements. The patients in this study were eating well and not at nutritional risk, thus patients with a poor appetite will be even less likely to meet their nutritional requirements. Steamplicity meals result in a lower energy intake than meals from a bulk cook-chill system, but similar protein intakes.

The Effect of Valve Timing Upon the Performance of a Supercharged Engine at Altitude and an Unsupercharged Engine at Sea Level

NASA Technical Reports Server (NTRS)

Schey, Oscar W; Biermann, Arnold E

1932-01-01

This investigation was conducted to determine the comparative effects of valve timing on the performance of an unsupercharged engine at sea level and a supercharged engine at altitude. The tests were conducted on the NACA universal test engine. The timing of the four valve events was varied over a wide range; the engine speeds were varied between 1,050 and 1,500 r.p.m.; the compression ratios were varied between 4.35:1 and 7.35:1. The conditions of exhaust pressure and carburetor pressure of a supercharged engine were simulated for altitudes between 0 and 18,000 feet. The results show that optimum valve timing for a supercharged engine at an altitude of 18,000 feet differs slightly from that for an unsupercharged engine at sea level. A small increase in power is obtained by using the optimum timing for 18,000 feet for altitudes above 5,000 feet. The timing of the intake opening and exhaust closing becomes more critical as the compression ratio is increased.

Flex Fuel Optimized SI and HCCI Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Guoming; Schock, Harold; Yang, Xiaojian

The central objective of the proposed work is to demonstrate an HCCI (homogeneous charge compression ignition) capable SI (spark ignited) engine that is capable of fast and smooth mode transition between SI and HCCI combustion modes. The model-based control technique was used to develop and validate the proposed control strategy for the fast and smooth combustion mode transition based upon the developed control-oriented engine; and an HCCI capable SI engine was designed and constructed using production ready two-step valve-train with electrical variable valve timing actuating system. Finally, smooth combustion mode transition was demonstrated on a metal engine within eight enginemore » cycles. The Chrysler turbocharged 2.0L I4 direct injection engine was selected as the base engine for the project and the engine was modified to fit the two-step valve with electrical variable valve timing actuating system. To develop the model-based control strategy for stable HCCI combustion and smooth combustion mode transition between SI and HCCI combustion, a control-oriented real-time engine model was developed and implemented into the MSU HIL (hardware-in-the-loop) simulation environment. The developed model was used to study the engine actuating system requirement for the smooth and fast combustion mode transition and to develop the proposed mode transition control strategy. Finally, a single cylinder optical engine was designed and fabricated for studying the HCCI combustion characteristics. Optical engine combustion tests were conducted in both SI and HCCI combustion modes and the test results were used to calibrate the developed control-oriented engine model. Intensive GT-Power simulations were conducted to determine the optimal valve lift (high and low) and the cam phasing range. Delphi was selected to be the supplier for the two-step valve-train and Denso to be the electrical variable valve timing system supplier. A test bench was constructed to develop control strategies for the electrical variable valve timing (VVT) actuating system and satisfactory electrical VVT responses were obtained. Target engine control system was designed and fabricated at MSU for both single-cylinder optical and multi-cylinder metal engines. Finally, the developed control-oriented engine model was successfully implemented into the HIL simulation environment. The Chrysler 2.0L I4 DI engine was modified to fit the two-step vale with electrical variable valve timing actuating system. A used prototype engine was used as the base engine and the cylinder head was modified for the two-step valve with electrical VVT actuating system. Engine validation tests indicated that cylinder #3 has very high blow-by and it cannot be reduced with new pistons and rings. Due to the time constraint, it was decided to convert the four-cylinder engine into a single cylinder engine by blocking both intake and exhaust ports of the unused cylinders. The model-based combustion mode transition control algorithm was developed in the MSU HIL simulation environment and the Simulink based control strategy was implemented into the target engine controller. With both single-cylinder metal engine and control strategy ready, stable HCCI combustion was achived with COV of 2.1% Motoring tests were conducted to validate the actuator transient operations including valve lift, electrical variable valve timing, electronic throttle, multiple spark and injection controls. After the actuator operations were confirmed, 15-cycle smooth combustion mode transition from SI to HCCI combustion was achieved; and fast 8-cycle smooth combustion mode transition followed. With a fast electrical variable valve timing actuator, the number of engine cycles required for mode transition can be reduced down to five. It was also found that the combustion mode transition is sensitive to the charge air and engine coolant temperatures and regulating the corresponding temperatures to the target levels during the combustion mode transition is the key for a smooth combustion mode transition. As a summary, the proposed combustion mode transition strategy using the hybrid combustion mode that starts with the SI combustion and ends with the HCCI combustion was experimentally validated on a metal engine. The proposed model-based control approach made it possible to complete the SI-HCCI combustion mode transition within eight engine cycles utilizing the well controlled hybrid combustion mode. Without intensive control-oriented engine modeling and HIL simulation study of using the hybrid combustion mode during the mode transition, it would be impossible to validate the proposed combustion mode transition strategy in a very short period.« less

Proportional Feedback Control of Energy Intake During Obesity Pharmacotherapy.

PubMed

Hall, Kevin D; Sanghvi, Arjun; Göbel, Britta

2017-12-01

Obesity pharmacotherapies result in an exponential time course for energy intake whereby large early decreases dissipate over time. This pattern of declining drug efficacy to decrease energy intake results in a weight loss plateau within approximately 1 year. This study aimed to elucidate the physiology underlying the exponential decay of drug effects on energy intake. Placebo-subtracted energy intake time courses were examined during long-term obesity pharmacotherapy trials for 14 different drugs or drug combinations within the theoretical framework of a proportional feedback control system regulating human body weight. Assuming each obesity drug had a relatively constant effect on average energy intake and did not affect other model parameters, our model correctly predicted that long-term placebo-subtracted energy intake was linearly related to early reductions in energy intake according to a prespecified equation with no free parameters. The simple model explained about 70% of the variance between drug studies with respect to the long-term effects on energy intake, although a significant proportional bias was evident. The exponential decay over time of obesity pharmacotherapies to suppress energy intake can be interpreted as a relatively constant effect of each drug superimposed on a physiological feedback control system regulating body weight. © 2017 The Obesity Society.

Effectiveness of a personalized ventilation system in reducing personal exposure against directly released simulated cough droplets.

PubMed

Pantelic, J; Tham, K W; Licina, D

2015-12-01

The inhalation intake fraction was used as an indicator to compare effects of desktop personalized ventilation and mixing ventilation on personal exposure to directly released simulated cough droplets. A cough machine was used to simulate cough release from the front, back, and side of a thermal manikin at distances between 1 and 4 m. Cough droplet concentration was measured with an aerosol spectrometer in the breathing zone of a thermal manikin. Particle image velocimetry was used to characterize the velocity field in the breathing zone. Desktop personalized ventilation substantially reduced the inhalation intake fraction compared to mixing ventilation for all investigated distances and orientations of the cough release. The results point out that the orientation between the cough source and the breathing zone of the exposed occupant is an important factor that substantially influences exposure. Exposure to cough droplets was reduced with increasing distance between cough source and exposed occupant. The results from this study show that an advanced air distribution system such as personalized ventilation reduces exposure to cough-released droplets better than commonly applied overhead mixing ventilation. This work can inform HVAC engineers about different aspects of air distribution systems’ performance and can serve as an aid in making critical design decisions. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petitpas, Guillaume; Whitesides, Russel

UQHCCI_2 propagates the uncertainties of mass-average quantities (temperature, heat capacity ratio) and the output performances (IMEP, heat release, CA50 and RI) of a HCCI engine test bench using the pressure trace, and intake and exhaust molar fraction and IVC temperature distributions, as inputs (those inputs may be computed using another code UQHCCI_2, or entered independently).

Bioenvironmental Engineer’s Guide to Indoor Air Quality Surveys

DTIC Science & Technology

2014-09-01

housekeeping practices •Fresh air intake located near contaminant source •Check for sewer line leak, septic tank leak, fuel tank leaks...make-up air •Dirty coils/filters •Sewer gas, drain traps, sanitary vents •Leaky tanks , spills •Cleaning products, pesticides •Poor

40 CFR 1065.202 - Data updating, recording, and control.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... 1065.202 Section 1065.202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments § 1065.202 Data updating, recording... Intake-air or raw-exhaust flow rate N/A 1 Hz means. § 1065.530, § 1065.545 Dilution air if actively...

40 CFR 1065.202 - Data updating, recording, and control.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... 1065.202 Section 1065.202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments § 1065.202 Data updating, recording...; § 1065.545 Intake-air or raw-exhaust flow rate 1 Hz means. § 1065.530; § 1065.545 Dilution air flow if...

40 CFR 1065.280 - Paramagnetic and magnetopneumatic O2 detection analyzers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments O2 Measurements § 1065... diluted exhaust for batch or continuous sampling. You may use O2 measurements with intake air or fuel flow... 57443, Sept. 15, 2011;79 FR 23762, Apr. 28, 2014] Air-to-Fuel Ratio Measurements ...

40 CFR 1065.202 - Data updating, recording, and control.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... 1065.202 Section 1065.202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments § 1065.202 Data updating, recording... Intake-air or raw-exhaust flow rate N/A 1 Hz means. § 1065.530, § 1065.545 Dilution air if actively...

40 CFR 1065.202 - Data updating, recording, and control.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... 1065.202 Section 1065.202 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments § 1065.202 Data updating, recording... Intake-air or raw-exhaust flow rate N/A 1 Hz means. § 1065.530, § 1065.545 Dilution air if actively...

mGluR1/5 activation in the lateral hypothalamus increases food intake via the endocannabinoid system.

PubMed

Sánchez-Fuentes, Asai; Marichal-Cancino, Bruno A; Méndez-Díaz, Mónica; Becerril-Meléndez, Alline L; Ruiz-Contreras, Alejandra E; Prospéro-Garcia, Oscar

2016-09-19

Mounting evidence has shown that glutamatergic and endocannabinoid systems in the hypothalamus regulate mammalian food intake. Stimulation of hypothalamic mGluR1/5 and CB1 receptors induces hyperphagia suggesting a possible interaction between these systems to control food intake. In addition, synthesis of endocannabinoids has been reported after mGluR1/5 stimulation in the brain. The aim of this study was to examine the potential cannabinergic activity in the food intake induction by lateral hypothalamic stimulation of mGluR1/5. Wistar albino male rats received bilateral infusions in the lateral hypothalamus (LH) of: (i) vehicle; (ii) (RS)-2-Chloro-5-hidroxyphenylglycine (CHPG; mGluR1/5 agonist); (iii) 2-AG (CB1 endogenous agonist); (iv) AM251 (CB1 antagonist); (v) tetrahydrolipstatin (THL, 1.2μg; diacyl-glycerol lipase inhibitor); and (vi) combinations of CHPG + with the other aforementioned drugs. Food intake was evaluated the first two hours after drug administration. CHPG significantly increased food intake; whereas CHPG in combination with a dose of 2-AG (with no effects on food intake) greatly increased food ingestion compared to CHPG alone. The increase induced by CHPG in food intake was prevented with AM251 or THL. These results suggest that activation of mGluR1/5 in the lateral hypothalamus induces an orexigenic effect via activation of the endocannabinoid system. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Variable valve timing in a homogenous charge compression ignition engine

DOEpatents

Lawrence, Keith E.; Faletti, James J.; Funke, Steven J.; Maloney, Ronald P.

2004-08-03

The present invention relates generally to the field of homogenous charge compression ignition engines, in which fuel is injected when the cylinder piston is relatively close to the bottom dead center position for its compression stroke. The fuel mixes with air in the cylinder during the compression stroke to create a relatively lean homogeneous mixture that preferably ignites when the piston is relatively close to the top dead center position. However, if the ignition event occurs either earlier or later than desired, lowered performance, engine misfire, or even engine damage, can result. The present invention utilizes internal exhaust gas recirculation and/or compression ratio control to control the timing of ignition events and combustion duration in homogeneous charge compression ignition engines. Thus, at least one electro-hydraulic assist actuator is provided that is capable of mechanically engaging at least one cam actuated intake and/or exhaust valve.

Characterization of Reactivity Controlled Compression Ignition (RCCI) Using Premixed Gasoline and Direct-Injected Gasoline with a Cetane Improver on a Multi-Cylinder Engine

DOE PAGES

Dempsey, Adam B.; Curran, Scott; Reitz, Rolf D.

2015-04-14

The focus of the present paper was to characterize Reactivity Controlled Compression Ignition (RCCI) using a single-fuel approach of gasoline and gasoline mixed with a commercially available cetane improver on a multi-cylinder engine. RCCI was achieved by port-injecting a certification grade 96 research octane gasoline and direct-injecting the same gasoline mixed with various levels of a cetane improver, 2-ethylhexyl nitrate (EHN). The EHN volume percentages investigated in the direct-injected fuel were 10, 5, and 2.5%. The combustion phasing controllability and emissions of the different fueling combinations were characterized at 2300 rpm and 4.2 bar brake mean effective pressure over amore » variety of parametric investigations including direct injection timing, premixed gasoline percentage, and intake temperature. Comparisons were made to gasoline/diesel RCCI operation on the same engine platform at nominally the same operating condition. The experiments were conducted on a modern four cylinder light-duty diesel engine that was modified with a port-fuel injection system while maintaining the stock direct injection fuel system. The pistons were modified for highly premixed operation and feature an open shallow bowl design. The results indicate that the authority to control the combustion phasing through the fuel delivery strategy (e.g., direct injection timing or premixed gasoline percentage) is not a strong function of the EHN concentration in the direct-injected fuel. It was also observed that NOx emissions are a strong function of the global EHN concentration in-cylinder and the combustion phasing. Finally, in general, NOx emissions are significantly elevated for gasoline/gasoline+EHN operation compared with gasoline/diesel RCCI operation at a given operating condition.« less

Constant speed control of four-stroke micro internal combustion swing engine

NASA Astrophysics Data System (ADS)

Gao, Dedong; Lei, Yong; Zhu, Honghai; Ni, Jun

2015-09-01

The increasing demands on safety, emission and fuel consumption require more accurate control models of micro internal combustion swing engine (MICSE). The objective of this paper is to investigate the constant speed control models of four-stroke MICSE. The operation principle of the four-stroke MICSE is presented based on the description of MICSE prototype. A two-level Petri net based hybrid model is proposed to model the four-stroke MICSE engine cycle. The Petri net subsystem at the upper level controls and synchronizes the four Petri net subsystems at the lower level. The continuous sub-models, including breathing dynamics of intake manifold, thermodynamics of the chamber and dynamics of the torque generation, are investigated and integrated with the discrete model in MATLAB Simulink. Through the comparison of experimental data and simulated DC voltage output, it is demonstrated that the hybrid model is valid for the four-stroke MICSE system. A nonlinear model is obtained from the cycle average data via the regression method, and it is linearized around a given nominal equilibrium point for the controller design. The feedback controller of the spark timing and valve duration timing is designed with a sequential loop closing design approach. The simulation of the sequential loop closure control design applied to the hybrid model is implemented in MATLAB. The simulation results show that the system is able to reach its desired operating point within 0.2 s, and the designed controller shows good MICSE engine performance with a constant speed. This paper presents the constant speed control models of four-stroke MICSE and carries out the simulation tests, the models and the simulation results can be used for further study on the precision control of four-stroke MICSE.

Multiple pure tone elimination strut assembly. [air breathing engines

NASA Technical Reports Server (NTRS)

Burcham, F. W. (Inventor)

1981-01-01

An acoustic noise elimination assembly is disclosed which has a capability for disrupting the continuity of fields of sound pressures forwardly projected from fans or rotors of a type commonly found in the fan or compressor first stage for air-breathing engines, when operating at tip speeds in the supersonic range. The assembly includes a tubular cowl defining a duct for delivering an air stream axially into the intake for a jet engine. A sound barrier, defined by a number of intersecting flat plates or struts has a line of intersection coincident with a longitudinal axis of the tubular cowl, which serves to disrupt the continuity of rotating fields of multiple pure tonal components of noise.

Dietary carbohydrates induce changes in glucosensing capacity and food intake of rainbow trout.

PubMed

Polakof, Sergio; Míguez, Jesús M; Soengas, José L

2008-08-01

We hypothesize that variations in dietary carbohydrate levels produce changes in glucosensor parameters in previously characterized glucosensing areas (hypothalamus and hindbrain) related with the regulation of food intake of a carnivorous fish species like rainbow trout. Therefore, we fed trout with standard, carbohydrate-free (CF) or high-carbohydrate (HC) diets for 10 days to assess changes in glucosensing system and food intake. Fish fed CF diet displayed hypoglycemia and increased food intake. Fish fed a HC diet displayed hyperglycemia and decreased food intake. Changes in food intake due to dietary carbohydrates were accompanied in hypothalamus and hindbrain of fish fed with HC diet by changes in parameters involved in glucosensing, such as increased glucose, glucose 6-phosphate, and glycogen levels and increased glucokinase (GK), glycogen synthase, and pyruvate kinase activities as well as increased GK and GLUT2 expression. All those results address for the first time in fish, despite the relative intolerance to glucose of carnivorous species, that dietary carbohydrates are important regulators of the glucosensing system in carnivorous fish, suggesting that the information generated by this system can be associated with the changes observed in food intake.

View of Pressure Tunnel Intake at Stehr Lake. Looking southeast ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Pressure Tunnel Intake at Stehr Lake. Looking southeast - Childs-Irving Hydroelectric Project, Childs System, Pressure Tunnel Intake, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

Cooling Water Intakes

EPA Pesticide Factsheets

Industries use large volumes of water for cooling. The water intakes pull large numbers of fish and other organisms into the cooling systems. EPA issues regulations on intake structures in order to minimize adverse environmental impacts.

Dietary intake and nutritional status in patients with systemic sclerosis.

PubMed Central

Lundberg, A C; Akesson, A; Akesson, B

1992-01-01

Oesophageal dysmotility and abnormalities of intestinal function are important manifestations in systemic sclerosis and may have a significant effect on nutrient absorption and nutritional status. In this study 30 patients with systemic sclerosis with symptoms from the gastrointestinal tract were compared with matched healthy control subjects with respect to nutrient intake (four day record), anthropometric measurements, and biochemical nutritional status. The intake of energy (8.1 and 8.4 MJ/day) and its distribution among nutrients did not differ between patients and control subjects, but the lower intake of dietary fibre among patients with systemic sclerosis suggests that they avoided food with a coarse structure, such as coarse bread. The intake of vegetables and fruit also tended to be lower among patients with systemic sclerosis. Half of the patients had a subnormal arm muscle circumference, and two patients also had a subnormal triceps skinfold thickness, indicating severe malnutrition. The concentration of ascorbic acid, alpha-tocopherol, carotene, selenium, and also the proportion of linoleic acid (18:2) in serum phosphatidylcholine was lower in patients than in control subjects. PMID:1332633

Comparison Of Intake Gate Closure Methods At Lower Granite, Little Goose, Lower Monumental, And Mcnary Dams Using Risk-Based Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gore, Bryan F.; Blackburn, Tyrone R.; Heasler, Patrick G.

2001-01-19

The objective of this report is to compare the benefits and costs of modifications proposed for intake gate closure systems at four hydroelectric stations on the Lower Snake and Upper Columbia Rivers in the Walla Walla District that are unable to meet the COE 10-minute closure rule due to the installation of fish screens. The primary benefit of the proposed modifications is to reduce the risk of damage to the station and environs when emergency intake gate closure is required. Consequently, this report presents the results and methodology of an extensive risk analysis performed to assess the reliability of powerhousemore » systems and the costs and timing of potential damages resulting from events requiring emergency intake gate closure. As part of this analysis, the level of protection provided by the nitrogen emergency closure system was also evaluated. The nitrogen system was the basis for the original recommendation to partially disable the intake gate systems. The risk analysis quantifies this protection level.« less

Dietary micronutrient intake and atherosclerosis in systemic lupus erythematosus.

PubMed

Lourdudoss, C; Elkan, A-C; Hafström, I; Jogestrand, T; Gustafsson, T; van Vollenhoven, R; Frostegård, J

2016-12-01

The aim of this study was to investigate the role of dietary micronutrient intake in systemic lupus erythematosus (SLE). This study included 111 SLE patients and 118 age and gender-matched controls. Data on diet (food frequency questionnaires) were linked with data on Systemic Lupus Activity Measure, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and carotid atherosclerotic/echolucent plaque (B-mode ultrasound). Dietary micronutrient intake were compared between SLE patients and controls and in relation to lupus activity and atherosclerosis in SLE. Associations between micronutrient intake and plaque were analyzed through logistic regression, adjusted for potential confounders. Micronutrient intake did not differ between patients and controls, and between lower and higher lupus activity, apart from the fact that phosphorus was associated with SLEDAI > 6. In SLE patients, some micronutrients were associated with atherosclerotic plaque, left side. Lower intake of riboflavin and phosphorus was associated with atherosclerotic plaque, left side (odds ratio (OR) 3.06, 95% confidence interval (CI) 1.12-8.40 and OR 4.36, 95% CI 1.53-12.39, respectively). Higher intake of selenium and thiamin was inversely associated with atherosclerotic plaque, left side (OR 0.28, 95% CI 0.09-0.89 and OR 0.26, 95% CI 0.08-0.80, respectively). In addition, higher intake of thiamin was inversely associated with echolucent plaque, left side (OR 0.22, 95% CI 0.06-0.84). Lower intake of folate was inversely associated with bilateral echolucent plaque (OR 0.36, 95% CI 0.13-0.99). SLE patients did not have different dietary micronutrient intake compared to controls. Phosphorus was associated with lupus activity. Riboflavin, phosphorus, selenium and thiamin were inversely associated with atherosclerotic plaque, left side in SLE patients, but not in controls. Dietary micronutrients may play a role in atherosclerosis in SLE. © The Author(s) 2016.

An open system approach to process reengineering in a healthcare operational environment.

PubMed

Czuchry, A J; Yasin, M M; Norris, J

2000-01-01

The objective of this study is to examine the applicability of process reengineering in a healthcare operational environment. The intake process of a mental healthcare service delivery system is analyzed systematically to identify process-related problems. A methodology which utilizes an open system orientation coupled with process reengineering is utilized to overcome operational and patient related problems associated with the pre-reengineered intake process. The systematic redesign of the intake process resulted in performance improvements in terms of cost, quality, service and timing.

Three-Dimensional Analysis and Modeling of a Wankel Engine

NASA Technical Reports Server (NTRS)

Raju, M. S.; Willis, E. A.

1991-01-01

A new computer code, AGNI-3D, has been developed for the modeling of combustion, spray, and flow properties in a stratified-charge rotary engine (SCRE). The mathematical and numerical details of the new code are described by the first author in a separate NASA publication. The solution procedure is based on an Eulerian-Lagrangian approach where the unsteady, three-dimensional Navier-Stokes equations for a perfect gas-mixture with variable properties are solved in generalized, Eulerian coordinates on a moving grid by making use of an implicit finite-volume, Steger-Warming flux vector splitting scheme. The liquid-phase equations are solved in Lagrangian coordinates. The engine configuration studied was similar to existing rotary engine flow-visualization and hot-firing test rigs. The results of limited test cases indicate a good degree of qualitative agreement between the predicted and measured pressures. It is conjectured that the impulsive nature of the torque generated by the observed pressure nonuniformity may be one of the mechanisms responsible for the excessive wear of the timing gears observed during the early stages of the rotary combustion engine (RCE) development. It was identified that the turbulence intensities near top-dead-center were dominated by the compression process and only slightly influenced by the intake and exhaust processes. Slow mixing resulting from small turbulence intensities within the rotor pocket and also from a lack of formation of any significant recirculation regions within the rotor pocket were identified as the major factors leading to incomplete combustion. Detailed flowfield results during exhaust and intake, fuel injection, fuel vaporization, combustion, mixing and expansion processes are also presented. The numerical procedure is very efficient as it takes 7 to 10 CPU hours on a CRAY Y-MP for one entire engine cycle when the computations are performed over a 31 x16 x 20 grid.

View of Sally May/Purple Mountain Siphon Intake. Looking southeast ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Sally May/Purple Mountain Siphon Intake. Looking southeast - Childs-Irving Hydroelectric Project, Childs System, Sally May-Purple Mountain Siphon Intake, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

Factors associated with health-related quality of life among operating engineers.

PubMed

Choi, Seung Hee; Redman, Richard W; Terrell, Jeffrey E; Pohl, Joanne M; Duffy, Sonia A

2012-11-01

Because health-related quality of life among blue-collar workers has not been well studied, the purpose of this study was to determine factors associated with health-related quality of life among Operating Engineers. With cross-sectional data from a convenience sample of 498 Operating Engineers, personal and health behavioral factors associated with health-related quality of life were examined. Multivariate linear regression analysis revealed that personal factors (older age, being married, more medical comorbidities, and depression) and behavioral factors (smoking, low fruit and vegetable intake, low physical activity, high body mass index, and low sleep quality) were associated with poor health-related quality of life. Operating Engineers are at risk for poor health-related quality of life. Underlying medical comorbidities and depression should be well managed. Worksite wellness programs addressing poor health behaviors may be beneficial.

Selection of NIR H2O absorption transitions for in-cylinder measurement of temperature in IC engines

NASA Astrophysics Data System (ADS)

Zhou, Xin; Liu, Xiang; Jeffries, Jay B.; Hanson, Ronald K.

2005-12-01

The water vapour spectrum in the 1.25-1.65 µm region is systematically analysed to find the best absorption transitions for sensitive measurement of in-cylinder gas temperature over short paths in an internal combustion engine. The strategy to select the optimum wavelength regions and absorption line combinations is developed for the time-varying pressures and temperatures expected during the compression portion of an engine cycle. We have identified 14 transitions of water vapour in this spectral region as promising for this application. From these transitions, 16 potential line pairs were considered for a wavelength-modulated absorption sensor for in-cylinder gas temperature during the compression stroke. Expected performance is modelled for the intake portion of two engine cycles that produce extreme temperature and pressure variations during compression.

Cryogenic Fluid Management Technology and Nuclear Thermal Propulsion

NASA Technical Reports Server (NTRS)

Taylor, Brian D.; Caffrey, Jarvis; Hedayat, Ali; Stephens, Jonathan; Polsgrove, Robert

2016-01-01

Cryogenic fluid management (CFM) is critical to the success of future nuclear thermal propulsion powered vehicles. While this is an issue for any propulsion system utilizing cryogenic propellants, this is made more challenging by the radiation flux produced by the reactor in a nuclear thermal rocket (NTR). Managing the cryogenic fuel to prevent propellant loss to boil off and leakage is needed to limit the required quantity of propellant to a reasonable level. Analysis shows deposition of energy into liquid hydrogen fuel tanks in the vicinity of the nuclear thermal engine. This is on top of ambient environment sources of heat. Investments in cryogenic/thermal management systems (some of which are ongoing at various organizations) are needed in parallel to nuclear thermal engine development in order to one day see the successful operation of an entire stage. High durability, low thermal conductivity insulation is one developmental need. Light weight cryocoolers capable of removing heat from large fluid volumes at temperatures as low as approx. 20 K are needed to remove heat leak from the propellant of an NTR. Valve leakage is an additional CFM issue of great importance. Leakage rates of state of the art, launch vehicle size valves (which is approximately the size valves needed for a Mars transfer vehicle) are quite high and would result in large quantities of lost propellant over a long duration mission. Additionally, the liquid acquisition system inside the propellant tank must deliver properly conditioned propellant to the feed line for successful engine operation and avoid intake of warm or gaseous propellant. Analysis of the thermal environment and the CFM technology development are discussed in the accompanying presentation.

40 CFR 92.5 - Reference materials.

Code of Federal Regulations, 2011 CFR

2011-07-01

... § 92.113 ASTM D 1945-91, Standard Test Method for Analysis of Natural Gas by Gas Chromatography § 92... Supercritical Fluid Chromatography § 92.113 ASTM E 29-93a, Standard Practice for Using Significant Digits in....119 SAE Recommended Practice J244, Measurement of Intake Air or Exhaust Gas Flow of Diesel Engines...

75 FR 26222 - Cadeville Gas Storage, LLC; Notice of Availability of the Environmental Assessment for the...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-11

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. CP10-16-000] Cadeville Gas... Storage Project April 30, 2010. The staff of the Federal Energy Regulatory Commission (FERC or Commission... fueled engines with air intake filters/silencers, critical grade exhaust silencer/catalyst, a triethylene...

46 CFR 112.50-1 - General.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Emergency Diesel and Gas Turbine Engine Driven Generator Sets § 112.50-1 General. (a) The prime mover of a generator set must have: (1) All accessories necessary for operation and protection of the prime mover; and... degrees C). (c) The room that has the generator set must have intake and exhaust ducts to supply adequate...

40 CFR 80.165 - Certification test procedures and standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., “Standard Test Method for Evaluating Unleaded Automotive Spark-Ignition Engine Fuel for Electronic Port Fuel.... The required test fuel must produce the accumulation of less than 100 mg of intake valve deposits on... Board, “Test Method for Evaluating Port Fuel Injector (PFI) Deposits in Vehicle Engines”, March 1, 1991...

40 CFR 80.165 - Certification test procedures and standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., “Standard Test Method for Evaluating Unleaded Automotive Spark-Ignition Engine Fuel for Electronic Port Fuel.... The required test fuel must produce the accumulation of less than 100 mg of intake valve deposits on... Board, “Test Method for Evaluating Port Fuel Injector (PFI) Deposits in Vehicle Engines”, March 1, 1991...

40 CFR 1065.280 - Paramagnetic and magnetopneumatic O2 detection analyzers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Measurement Instruments O2 Measurements § 1065... diluted exhaust for batch or continuous sampling. You may use O2 measurements with intake air or fuel flow...), regardless of the uncompensated signal's bias. [73 FR 37300, June 30, 2008] Air-to-Fuel Ratio Measurements ...

Dietary Differences in Male Workers among Smaller Occupational Groups within Large Occupational Categories: Findings from the Japan Environment and Children's Study (JECS).

PubMed

Tanaka, Rie; Tsuji, Mayumi; Senju, Ayako; Kusuhara, Koichi; Kawamoto, Toshihiro

2018-05-11

Studies examining workers' diet according to smaller occupational groups within "large occupational categories" are sparse. The aim of this study was to examine the potential differences in workers' diets based on the classification of workers into smaller occupational groups that comprise "large occupational categories". The subjects of this study were working fathers who had participated in the Japan Environment and Children's Study (N = 38,656). Energy and nutrient intake were calculated based on data collected from the Food Frequency Questionnaire. Occupations were classified according to the Japanese Standard Occupational Classification. Logistic regression analyses were performed to examine the adherence to current dietary recommendations within smaller occupational groups. In particular, significant differences were observed among the categorical groups of "professional and engineering workers", "service workers", and "agricultural, forestry, and fishery workers". In "professional and engineering workers", teachers showed higher odds of adherence to calcium intake recommendations compared with nurses (OR, 2.54; 95% CI, 2.02⁻3.14; p < 0.001). In "agricultural, forestry, and fishery workers", agriculture workers showed higher odds of adherence to calcium (OR, 2.15; 95% CI, 1.46⁻3.15; p < 0.001) and vitamin C (OR 1.90, 95% CI 1.31⁻2.74, p = 0.001) intake recommendations compared with forestry and fishery workers. These findings may be beneficial from a research perspective as well as in the development of more effective techniques to improve workers' diet and health.

Real-time CO2 sensor for the optimal control of electronic EGR system

NASA Astrophysics Data System (ADS)

Kim, Gwang-jung; Choi, Byungchul; Choi, Inchul

2013-12-01

In modern diesel engines, EGR (Exhaust Gas Recirculation) is an important technique used in nitrogen oxide (NOx) emission reduction. This paper describes the development and experimental results of a fiber-optical sensor using a 2.7 μm wavelength absorption to quantify the simultaneous CO2 concentration which is the primary variable of EGR rate (CO2 in the exhaust gas versus CO2 in the intake gas, %). A real-time laser absorption method was developed using a DFB (distributed feedback) diode laser and waveguide to make optimal design and control of electronic EGR system required for `Euro-6' and `Tier 4 Final' NOx emission regulations. While EGR is effective to reduce NOx significantly, the amount of HC and CO is increased in the exhaust gas if EGR rate is not controlled based on driving conditions. Therefore, it is important to recirculate an appropriate amount of exhaust gas in the operation condition generating high volume of NOx. In this study, we evaluated basic characteristics and functions of our optical sensor and studied basically in order to find out optimal design condition. We demonstrated CO2 measurement speed, accuracy and linearity as making a condition similar to real engine through the bench-scale experiment.

Thermochemistry of CaO-MgO-Al2O3-SiO2 (CMAS) and Advanced Thermal and Environmental Barrier Coating Systems

NASA Technical Reports Server (NTRS)

Costa, Gustavo; Zhu, Dongming

2017-01-01

CaO-MgO-Al2O3-SiO2 (CMAS) oxides are constituents in a broad number of materials and minerals which have recently inferred to discussions in materials science, planetary science, geochemistry and cosmochemistry communities. In materials science, there is increasing interest in the degradation studies of thermal (TBC) and environmental (EBC) barrier coatings of gas turbines by molten CMAS. CMAS minerals usually are carried by the intake air into gas turbines, e.g. in aircraft engines, and their deposits react at high temperatures (1000C) with the coating materials. This causes degradation and accelerated failure of the static and rotating components of the turbine engines. We discuss some preliminary results of the reactions between CMAS and Rare-Earth (RE Y, Yb, Dy, Gd, Nd and Sm) oxide stabilized ZrO2 or HfO2 systems, and the stability of the resulting oxides and silicates. Plasma sprayed hollow tube samples ( 2.2 mm and 26 mm height) were half filled with CMAS powder, wrapped and sealed with platinum foil, and heat treated at 1310 C for 5h. Samples were characterized by differential scanning calorimetry, X-ray diffraction and cross section electron microscopy analysis.

14-Methoxymetopon, a highly potent mu opioid agonist, biphasically affects ethanol intake in Sardinian alcohol-preferring rats.

PubMed

Sabino, Valentina; Cottone, Pietro; Steardo, Luca; Schmidhammer, Helmut; Zorrilla, Eric P

2007-07-01

Increased opioidergic activity is thought to increase the propensity to consume ethanol. However, the dose monotonicity and receptor subtype for this effect remain uncertain. 14-methoxymetopon is a centrally acting, selective micro opioid receptor agonist with greater systemic antinociceptive potency than morphine and a putatively improved therapeutic index. To determine whether 14-methoxymetopon influenced voluntary ethanol intake in Sardinian alcohol-preferring (sP) rats. Male sP rats with continuous 2-bottle choice access to ethanol (10% v/v) or water were subjects. The effects of systemic 14-methoxymetopon administration (2, 5, 12.25, 30 micro/kg, s.c.) on 4-h ethanol intake were determined. The ability of naltrexone (50 micro/kg, s.c.), an opioid antagonist, to block actions of 14-methoxymetopon (12.25, 30 micro/kg, s.c.) was examined as were the effects of 14-methoxymetopon (12.25 micro/kg, s.c.) on self-administered blood alcohol levels (BALs) and clearance of a passive ethanol bolus (1 g/kg). Finally, the effects of central 14-methoxymetopon administration (0.0003-100 ng, i.c.v.) on 4-h ethanol intake were evaluated. Systemic 14-methoxymetopon very potently and dose-dependently suppressed ethanol and food intake for 30 min, followed by a greater, longer-lasting, and behaviorally specific increase in ethanol intake. The increased ethanol intake led to threefold higher BALs, was naltrexone-reversible, and not due to altered ethanol clearance. Intracerebroventricular 14-methoxymetopon administration rapidly altered ethanol intake per an inverted U-shaped dose-response function, increasing it at a 10 pg dose, while suppressing it at a 10,000-fold higher dose. The novel mu analgesic increases ethanol intake, a potential therapeutic liability, and results suggest a non-monotonic influence of brain mu opioid receptor stimulation on ethanol intake.

Computed tomography measurement of gaseous fuel concentration by infrared laser light absorption

NASA Astrophysics Data System (ADS)

Kawazoe, Hiromitsu; Inagaki, Kazuhisa; Emi, Y.; Yoshino, Fumio

1997-11-01

A system to measure gaseous hydrocarbon distributions was devised, which is based on IR light absorption by C-H stretch mode of vibration and computed tomography method. It is called IR-CT method in the paper. Affection of laser light power fluctuation was diminished by monitoring source light intensity by the second IR light detector. Calibration test for methane fuel was carried out to convert spatial data of line absorption coefficient into quantitative methane concentration. This system was applied to three flow fields. The first is methane flow with lifted flame which is generated by a gourd-shaped fuel nozzle. Feasibility of the IR-CT method was confirmed through the measurement. The second application is combustion field with diffusion flame. Calibration to determine absorptivity was undertaken, and measured line absorption coefficient was converted spatial fuel concentration using corresponding temperature data. The last case is modeled in cylinder gas flow of internal combustion engine, where gaseous methane was led to the intake valve in steady flow state. The fuel gas flow simulates behavior of gaseous gasoline which is evaporated at intake valve tulip. Computed tomography measurement of inner flow is essentially difficult because of existence of surrounding wall. In this experiment, IR laser beam was led to planed portion by IR light fiber. It is found that fuel convection by airflow takes great part in air-fuel mixture formation and the developed IR-CT system to measure fuel concentration is useful to analyze air-fuel mixture formation process and to develop new combustors.

Reduction of Energy Intake using Just-In-Time Feedback from a Wearable Sensor System

PubMed Central

Farooq, Muhammad; McCrory, Megan A.; Sazonov, Edward

2017-01-01

Objective This work explored the potential use of a wearable sensor system for providing just-in-time (JIT) feedback on the progression of a meal and tested its ability to reduce the total food mass intake. Methods Eighteen participants each consumed three meals in a lab while monitored by a wearable sensor system capable of accurately tracking chew counts. The baseline visit was used to establish the self-determined ingested mass and the associated chew counts. Real-time feedback on chew counts was provided in the next two visits during which the target chew counts was either the same as that at baseline or the baseline chew counts reduced by 25%, in randomized order. The target was concealed from the participant and from the experimenter. Nonparametric repeated-measures ANOVA were performed to compare mass of intake, meal duration, and ratings of hunger, appetite, and thirst across 3 meals. Results JIT feedback targeting a 25% reduction in chew counts resulted in a reduction in mass and energy intake without affecting perceived hunger or fullness. Conclusion JIT feedback on chewing behavior may reduce intake within a meal. This system can be further used to help develop individualized strategies to provide just-in-time adaptive interventions for reducing energy intake. PMID:28233942

Reduction of energy intake using just-in-time feedback from a wearable sensor system.

PubMed

Farooq, Muhammad; McCrory, Megan A; Sazonov, Edward

2017-04-01

This work explored the potential use of a wearable sensor system for providing just-in-time (JIT) feedback on the progression of a meal and tested its ability to reduce the total food mass intake. Eighteen participants consumed three meals each in a lab while monitored by a wearable sensor system capable of accurately tracking chew counts. The baseline visit was used to establish the self-determined ingested mass and the associated chew counts. Real-time feedback on chew counts was provided in the next two visits, during which the target chew count was either the same as that at baseline or the baseline chew count reduced by 25% (in randomized order). The target was concealed from the participant and from the experimenter. Nonparametric repeated-measures ANOVAs were performed to compare mass of intake, meal duration, and ratings of hunger, appetite, and thirst across three meals. JIT feedback targeting a 25% reduction in chew counts resulted in a reduction in mass and energy intake without affecting perceived hunger or fullness. JIT feedback on chewing behavior may reduce intake within a meal. This system can be further used to help develop individualized strategies to provide JIT adaptive interventions for reducing energy intake. © 2017 The Obesity Society.

Walk-In Triage Systems in University Counseling Centers

ERIC Educational Resources Information Center

Shaffer, Katharine S.; Love, Michael M.; Chapman, Kelsey M.; Horn, Angela J.; Haak, Patricia P.; Shen, Claire Y. W.

2017-01-01

To meet the complex mental health needs of students, some university counseling centers (UCCs) have implemented walk-in triage intake systems, which have not yet been empirically investigated. This study compared client and clinician differences (N = 5564) between a traditional scheduled intake system (Year 1) and a walk-in triage system (Year 2)…

Brain dopamine and serotonin transporter binding are associated with visual attention bias for food in lean men.

PubMed

Koopman, K E; Roefs, A; Elbers, D C E; Fliers, E; Booij, J; Serlie, M J; la Fleur, S E

2016-06-01

In rodents, the striatal dopamine (DA) system and the (hypo)thalamic serotonin (5-HT) system are involved in the regulation of feeding behavior. In lean humans, little is known about the relationship between these brain neurotransmitter systems and feeding. We studied the relationship between striatal DA transporters (DAT) and diencephalic 5-HT transporters (SERT), behavioral tasks and questionnaires, and food intake. We measured striatal DAT and diencephalic SERT binding with [123I]FP-CIT SPECT in 36 lean male subjects. Visual attention bias for food (detection speed and distraction time) and degree of impulsivity were measured using response-latency-based computer tasks. Craving and emotional eating were assessed with questionnaires and ratings of hunger by means of VAS scores. Food intake was assessed through a self-reported online diet journal. Striatal DAT and diencephalic SERT binding negatively correlated with food detection speed (p = 0.008, r = -0.50 and p = 0.002, r = -0.57, respectively), but not with food distraction time, ratings of hunger, craving or impulsivity. Striatal DAT and diencephalic SERT binding did not correlate with free choice food intake, whereas food detection speed positively correlated with total caloric intake (p = 0.001, r = 0.60), protein intake (p = 0.01, r = 0.44), carbohydrate intake (p = 0.03, r = 0.39) and fat intake (p = 0.06, r = 0.35). These results indicate a role for the central 5-HT and DA system in the regulation of visual attention bias for food, which contributes to the motivation to eat, in non-obese, healthy humans. In addition, this study confirms that food detection speed, measured with the latency-based computer task, positively correlates with total food and macronutrient intake.

1. RUINED PORTION OF SANTA ANA CANAL INTAKE ALONGSIDE SAR3 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. RUINED PORTION OF SANTA ANA CANAL INTAKE ALONGSIDE SAR-3 SYSTEM TUNNEL, JUST TO SOUTH OF SAR-2. VIEW TO SOUTHEAST. - Santa Ana River Hydroelectric System, Abandoned Tunnel, Redlands, San Bernardino County, CA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dempsey, Adam B.; Curran, Scott; Reitz, Rolf D.

The focus of the present paper was to characterize Reactivity Controlled Compression Ignition (RCCI) using a single-fuel approach of gasoline and gasoline mixed with a commercially available cetane improver on a multi-cylinder engine. RCCI was achieved by port-injecting a certification grade 96 research octane gasoline and direct-injecting the same gasoline mixed with various levels of a cetane improver, 2-ethylhexyl nitrate (EHN). The EHN volume percentages investigated in the direct-injected fuel were 10, 5, and 2.5%. The combustion phasing controllability and emissions of the different fueling combinations were characterized at 2300 rpm and 4.2 bar brake mean effective pressure over amore » variety of parametric investigations including direct injection timing, premixed gasoline percentage, and intake temperature. Comparisons were made to gasoline/diesel RCCI operation on the same engine platform at nominally the same operating condition. The experiments were conducted on a modern four cylinder light-duty diesel engine that was modified with a port-fuel injection system while maintaining the stock direct injection fuel system. The pistons were modified for highly premixed operation and feature an open shallow bowl design. The results indicate that the authority to control the combustion phasing through the fuel delivery strategy (e.g., direct injection timing or premixed gasoline percentage) is not a strong function of the EHN concentration in the direct-injected fuel. It was also observed that NOx emissions are a strong function of the global EHN concentration in-cylinder and the combustion phasing. Finally, in general, NOx emissions are significantly elevated for gasoline/gasoline+EHN operation compared with gasoline/diesel RCCI operation at a given operating condition.« less

[STUDYING THE ROLE OF BRAIN MELANOCORTIN RECEPTORS IN THE SUPPRESSING OF FOOD INTAKE UNDER ETHER STRESS IN MICE].

PubMed

Bazhan, N M; Kulikova, E V; Makarova, E N; Yakovleva, T V; Kazantseva, A Yu

2015-12-01

Melanocortin (MC) system regulates food intake under the rest conditions. Stress inhibits food intake. It is not clear whether brain MC system is involved in stress-induced anorexia in mice. The aim of the work was to investigate the effect of pharmacological blockade and activation of brain MC receptors on food intake under stress. C57B1/6J male mice were subjected to ether stress (0.5 minute ether anesthesia) before the administration of saline solution or synthetic non-selective blocker (SHU9119) or agonist (Melanotan II) of MC receptors into the lateral brain ventricle. Food intake was pre-stimulated with 17 hours of fasting in all mice. Ether stress decreased food intake, increased the plasma corticosterone level and hypothalamic mRNA AgRP (natural MC receptor antagonist) level at 1 hour after the stress. Pharmacological blockade of the MC receptors weakened stress-induced anorexia and decreased mRNA AgRP level in the hypothalamus. Pharmacological stimulation of the MC receptors enhanced ether stress-induced anorexia and hypercortisolism. Thus, our data demonstrated that the central MC system was involved in the development of stress-induced anorexia in mice.

40 CFR 1065.546 - Validation of minimum dilution ratio for PM batch sampling.

Code of Federal Regulations, 2012 CFR

2012-07-01

... chemical balance terms as given in § 1065.655(e). You may determine the raw exhaust flow rate based on the measured intake air and dilute exhaust molar flow rates and the dilute exhaust chemical balance terms as... air, fuel rate measurements, and fuel properties, consistent with good engineering judgment. (b...

40 CFR 1065.546 - Validation of minimum dilution ratio for PM batch sampling.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chemical balance terms as given in § 1065.655(e). You may determine the raw exhaust flow rate based on the measured intake air and dilute exhaust molar flow rates and the dilute exhaust chemical balance terms as... air, fuel rate measurements, and fuel properties, consistent with good engineering judgment. (b...

40 CFR 1065.546 - Verification of minimum dilution ratio for PM batch sampling.

Code of Federal Regulations, 2014 CFR

2014-07-01

... chemical balance terms as given in § 1065.655(e). You may determine the raw exhaust flow rate based on the measured intake air and dilute exhaust molar flow rates and the dilute exhaust chemical balance terms as... air, fuel rate measurements, and fuel properties, consistent with good engineering judgment. (b...

40 CFR Appendix Viii to Part 85 - Vehicle and Engine Parameters and Specifications

Code of Federal Regulations, 2010 CFR

2010-07-01

... pressure. 3. Valves (intake and exhaust). a. Head diameter dimension. b. Valve lifter or actuator type and... diameter dimension. b. Valve lifter or actuator type and valve lash dimension. 5. Camshaft timing. a. Valve... dimension. b. Valve lifter or actuator type and valve lash dimension. 5. Camshaft timing. a. Valve opening...

40 CFR Appendix Viii to Part 85 - Vehicle and Engine Parameters and Specifications

Code of Federal Regulations, 2011 CFR

2011-07-01

... pressure. 3. Valves (intake and exhaust). a. Head diameter dimension. b. Valve lifter or actuator type and... diameter dimension. b. Valve lifter or actuator type and valve lash dimension. 5. Camshaft timing. a. Valve... dimension. b. Valve lifter or actuator type and valve lash dimension. 5. Camshaft timing. a. Valve opening...

View of Sally May/Purple Mountain Siphon Intake house from the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of Sally May/Purple Mountain Siphon Intake house from the south showing the flume existing. Looking north - Childs-Irving Hydroelectric Project, Childs System, Sally May-Purple Mountain Siphon Intake, Forest Service Road 708/502, Camp Verde, Yavapai County, AZ

Adaptive engine injection for emissions reduction

DOEpatents

Reitz, Rolf D. : Sun, Yong

2008-12-16

NOx and soot emissions from internal combustion engines, and in particular compression ignition (diesel) engines, are reduced by varying fuel injection timing, fuel injection pressure, and injected fuel volume between low and greater engine loads. At low loads, fuel is injected during one or more low-pressure injections occurring at low injection pressures between the start of the intake stroke and approximately 40 degrees before top dead center during the compression stroke. At higher loads, similar injections are used early in each combustion cycle, in addition to later injections which preferably occur between about 90 degrees before top dead center during the compression stroke, and about 90 degrees after top dead center during the expansion stroke (and which most preferably begin at or closely adjacent the end of the compression stroke). These later injections have higher injection pressure, and also lower injected fuel volume, than the earlier injections.

NO.sub.x reduction method

DOEpatents

Sekar, Ramanujam R.; Hoppie, Lyle O.

1996-01-01

A method of reducing oxides of nitrogen (NO.sub.X) in the exhaust of an internal combustion engine includes producing oxygen enriched air and nitrogen enriched air by an oxygen enrichment device. The oxygen enriched air may be provided to the intake of the internal combustion engine for mixing with fuel. In order to reduce the amount of NO.sub.X in the exhaust of the internal combustion engine, the molecular nitrogen in the nitrogen enriched air produced by the oxygen enrichment device is subjected to a corona or arc discharge so as to create a plasma and as a result, atomic nitrogen. The resulting atomic nitrogen then is injected into the exhaust of the internal combustion engine causing the oxides of nitrogen in the exhaust to be reduced into nitrogen and oxygen. In one embodiment of the present invention, the oxygen enrichment device that produces both the oxygen and nitrogen enriched air can include a selectively permeable membrane.

Numerical simulation of the flow field and fuel sprays in an IC engine

NASA Technical Reports Server (NTRS)

Nguyen, H. L.; Schock, H. J.; Ramos, J. I.; Carpenter, M. H.; Stegeman, J. D.

1987-01-01

A two-dimensional model for axisymmetric piston-cylinder configurations is developed to study the flow field in two-stroke direct-injection Diesel engines under motored conditions. The model accounts for turbulence by a two-equation model for the turbulence kinetic energy and its rate of dissipation. A discrete droplet model is used to simulate the fuel spray, and the effects of the gas phase turbulence on the droplets is considered. It is shown that a fluctuating velocity can be added to the mean droplet velocity every time step if the step is small enough. Good agreement with experimental data is found for a range of ambient pressures in Diesel engine-type microenvironments. The effects of the intake swirl angle in the spray penetration, vaporization, and mixing in a uniflow-scavenged two-stroke Diesel engine are analyzed. It is found that the swirl increases the gas phase turbulence levels and the rates of vaporization.

Iterative Development of an Online Dietary Recall Tool: INTAKE24.

PubMed

Simpson, Emma; Bradley, Jennifer; Poliakov, Ivan; Jackson, Dan; Olivier, Patrick; Adamson, Ashley J; Foster, Emma

2017-02-09

Collecting large-scale population data on dietary intake is challenging, particularly when resources and funding are constrained. Technology offers the potential to develop novel ways of collecting large amounts of dietary information while making it easier, more convenient, intuitive, and engaging for users. INTAKE24 is an online multiple pass 24 h dietary recall tool developed for use in national food and nutrition surveys. The development of INTAKE24 was a four-stage iterative process of user interaction and evaluation with the intended end users, 11-24 years old. A total of 80 11-24 years old took part in the evaluation, 20 at each stage. Several methods were used to elicit feedback from the users including, 'think aloud', 'eye tracking', semi-structured interviews, and a system usability scale. Each participant completed an interviewer led recall post system completion. Key system developments generated from the user feedback included a 'flat' interface, which uses only a single interface screen shared between all of the various activities (e.g., free text entry, looking up foods in the database, portion size estimation). Improvements to the text entry, search functionality, and navigation around the system were also influenced through feedback from users at each stage. The time to complete a recall using INTAKE24 almost halved from the initial prototype to the end system, while the agreement with an interviewer led recall improved. Further developments include testing the use of INTAKE24 with older adults and translation into other languages for international use. Our future aim is to validate the system with recovery biomarkers.

Iterative Development of an Online Dietary Recall Tool: INTAKE24

PubMed Central

Simpson, Emma; Bradley, Jennifer; Poliakov, Ivan; Jackson, Dan; Olivier, Patrick; Adamson, Ashley J.; Foster, Emma

2017-01-01

Collecting large-scale population data on dietary intake is challenging, particularly when resources and funding are constrained. Technology offers the potential to develop novel ways of collecting large amounts of dietary information while making it easier, more convenient, intuitive, and engaging for users. INTAKE24 is an online multiple pass 24 h dietary recall tool developed for use in national food and nutrition surveys. The development of INTAKE24 was a four-stage iterative process of user interaction and evaluation with the intended end users, 11–24 years old. A total of 80 11–24 years old took part in the evaluation, 20 at each stage. Several methods were used to elicit feedback from the users including, ‘think aloud’, ‘eye tracking’, semi-structured interviews, and a system usability scale. Each participant completed an interviewer led recall post system completion. Key system developments generated from the user feedback included a ‘flat’ interface, which uses only a single interface screen shared between all of the various activities (e.g., free text entry, looking up foods in the database, portion size estimation). Improvements to the text entry, search functionality, and navigation around the system were also influenced through feedback from users at each stage. The time to complete a recall using INTAKE24 almost halved from the initial prototype to the end system, while the agreement with an interviewer led recall improved. Further developments include testing the use of INTAKE24 with older adults and translation into other languages for international use. Our future aim is to validate the system with recovery biomarkers. PMID:28208763

Experimental investigation of regulated and unregulated emissions from a diesel engine fueled with Euro V diesel fuel and fumigation methanol

NASA Astrophysics Data System (ADS)

Zhang, Z. H.; Cheung, C. S.; Chan, T. L.; Yao, C. D.

2010-03-01

Experiments were conducted on a four-cylinder direct-injection diesel engine with part of the engine load taken up by fumigation methanol injected into the air intake of each cylinder to investigate the regulated and unregulated gaseous emissions and particulate emission of the engine under five engine loads at an engine speed of 1920 rev min -1. The fumigation methanol was injected to top up 10%, 20% and 30% of the engine load under different engine operating conditions. The experimental results show that at low engine loads, the brake thermal efficiency (BTE) decreases with increase in fumigation methanol; but at high engine loads, the BTE is not significantly affected by fumigation methanol. The fumigation methanol results in significant increase in hydrocarbon (HC), carbon monoxide (CO) and nitrogen dioxide (NO 2) emissions, but decrease in nitrogen oxides (NO x). For the unregulated gaseous emissions, unburned methanol, formaldehyde and BTX (benzene, toluene and xylene) emissions increase but ethyne, ethene and 1,3-butadiene emissions decrease. Particulate mass and number concentrations also decrease with increase in fumigation methanol. A diesel oxidation catalyst (DOC) is found to reduce significantly most of the pollutants, including the air toxics, when the exhaust gas temperature is sufficiently high.

DETAIL OF WATER INTAKES FOR FIREFIGHTING SYSTEM ON STARBOARD SIDE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL OF WATER INTAKES FOR FIREFIGHTING SYSTEM ON STARBOARD SIDE OF BOAT UNDER THE WATERLINE. ZINCS ARE ALSO ADDED HERE TO PRESERVE THE METAL. - Fireboat JOHN J. HARVEY, Pier 63, North River, New York County, NY

Reducing emissions by using special air filters for internal combustion engines

NASA Astrophysics Data System (ADS)

Birtok-Băneasă, C.; Raţiu, S. A.; Alexa, V.; Crăciun, A. L.; Josan, A.; Budiul-Berghian, A.

2017-05-01

This paper presents the experimental methodology to carry out functional performance tests for an air filter with a particular design of its housing, generically named Super absorbing YXV „Air by Corneliu”, patented and homologated by the Romanian Automotive Registry, to which numerous prizes and medals were awarded at national and international innovations salons. The tests were carried out in the Internal Combustion Engines Laboratory, within the specialization “Road vehicles” belonging to the Faculty of Engineering Hunedoara, component of Politehnica University of Timisoara. The scope of the study is to optimise the air intake into the engine cylinders by reducing the gas-dynamic resistances caused by the air filter and, therefore, to achieve higher energy efficiency, i.e. fuel consumption reduction and engine performance increase. We present some comparative values of various operating parameters of the engine fitted, in the first measuring session, with the original filter, and then with the studied filter. The data collected shows a reduction in fuel consumption by using this type of filter, which leads to lower emissions.

Effect of thermal barrier coating with various blends of pumpkin seed oil methyl ester in DI diesel engine

NASA Astrophysics Data System (ADS)

Karthickeyan, V.; Balamurugan, P.

2017-10-01

The rise in oil prices, dependency on fossil fuels, degradation of non-renewable energy resources and global warming strives to find a low-carbon content alternative fuel to the conventional fuel. In the present work, Partially Stabilized Zirconia (PSZ) was used as a thermal barrier coating in piston head, cylinder head and intake and exhaust valves using plasma spray technique, which provided a rise in combustion chamber temperature. With the present study, the effects of thermal barrier coating on the blends of Pumpkin Seed Oil Methyl Ester (PSOME) were observed in both the coated and uncoated engine. Performance and emission characteristics of the PSOME in coated and uncoated engines were observed and compared. Increased thermal efficiency and reduced fuel consumption were observed for B25 and diesel in coated and uncoated engine. On comparing with the other biodiesel samples, B25 exhibited lower HC, NOx and smoke emissions in thermally coated engine than uncoated engine. After 100 h of operation, no anamolies were found in the thermally coated components except minor cracks were identified in the edges of the piston head.

A STRATEGY FOR PROTECTING CIRCULATING SEAWATER SYSTEMS FROM OIL SPILLS

EPA Science Inventory

A strategy is described for establishing a simple, inexpensive monitoring program for determining approximate levels of petroleum hydrocarbons in ambient water collected near intake structures of circulating seawater systems. The ambient water is obtained from the depth of intake...

Divers muscle Fitzpatrick`s mussels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hobbs, B.; Kahabka, J.

1996-01-01

This article describes how an effective manual cleaning technique has helped rid submerged intake structures of this passive-aggressive pest. The New York Power Authority`s (NYPA) James A. Fitzpatrick (JAF) Nuclear Power Plant is located in Lycoming, NY, on the southeast shore of Lake Ontario. An 850-MWe, GE-design boiling water reactor (BWR), the unit has been in service since 1975. Water drawn from the Lake supplies cooling to plant loads via the circulating water system and three service water systems. These share a common intake system consisting of an offshore cap (crib), horizontal intake tunnel, two vertical risers and forebay/screenwell area.

Modified pressure loss model for T-junctions of engine exhaust manifold

NASA Astrophysics Data System (ADS)

Wang, Wenhui; Lu, Xiaolu; Cui, Yi; Deng, Kangyao

2014-11-01

The T-junction model of engine exhaust manifolds significantly influences the simulation precision of the pressure wave and mass flow rate in the intake and exhaust manifolds of diesel engines. Current studies have focused on constant pressure models, constant static pressure models and pressure loss models. However, low model precision is a common disadvantage when simulating engine exhaust manifolds, particularly for turbocharged systems. To study the performance of junction flow, a cold wind tunnel experiment with high velocities at the junction of a diesel exhaust manifold is performed, and the variation in the pressure loss in the T-junction under different flow conditions is obtained. Despite the trend of the calculated total pressure loss coefficient, which is obtained by using the original pressure loss model and is the same as that obtained from the experimental results, large differences exist between the calculated and experimental values. Furthermore, the deviation becomes larger as the flow velocity increases. By improving the Vazsonyi formula considering the flow velocity and introducing the distribution function, a modified pressure loss model is established, which is suitable for a higher velocity range. Then, the new model is adopted to solve one-dimensional, unsteady flow in a D6114 turbocharged diesel engine. The calculated values are compared with the measured data, and the result shows that the simulation accuracy of the pressure wave before the turbine is improved by 4.3% with the modified pressure loss model because gas compressibility is considered when the flow velocities are high. The research results provide valuable information for further junction flow research, particularly the correction of the boundary condition in one-dimensional simulation models.

Invited Review. Combustion instability in spray-guided stratified-charge engines. A review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fansler, Todd D.; Reuss, D. L.; Sick, V.

2015-02-02

Our article reviews systematic research on combustion instabilities (principally rare, random misfires and partial burns) in spray-guided stratified-charge (SGSC) engines operated at part load with highly stratified fuel -air -residual mixtures. Results from high-speed optical imaging diagnostics and numerical simulation provide a conceptual framework and quantify the sensitivity of ignition and flame propagation to strong, cyclically varying temporal and spatial gradients in the flow field and in the fuel -air -residual distribution. For SGSC engines using multi-hole injectors, spark stretching and locally rich ignition are beneficial. Moreover, combustion instability is dominated by convective flow fluctuations that impede motion of themore » spark or flame kernel toward the bulk of the fuel, coupled with low flame speeds due to locally lean mixtures surrounding the kernel. In SGSC engines using outwardly opening piezo-electric injectors, ignition and early flame growth are strongly influenced by the spray's characteristic recirculation vortex. For both injection systems, the spray and the intake/compression-generated flow field influence each other. Factors underlying the benefits of multi-pulse injection are identified. Finally, some unresolved questions include (1) the extent to which piezo-SGSC misfires are caused by failure to form a flame kernel rather than by flame-kernel extinction (as in multi-hole SGSC engines); (2) the relative contributions of partially premixed flame propagation and mixing-controlled combustion under the exceptionally late-injection conditions that permit SGSC operation on E85-like fuels with very low NO x and soot emissions; and (3) the effects of flow-field variability on later combustion, where fuel-air-residual mixing within the piston bowl becomes important.« less

Cold flow simulation of an internal combustion engine with vertical valves using layering approach

NASA Astrophysics Data System (ADS)

Martinas, G.; Cupsa, O. S.; Stan, L. C.; Arsenie, A.

2015-11-01

Complying with emission requirements and fuel consumption efficiency are the points which drive any development of internal combustion engine. Refinement of the process of combustion and mixture formation, together with in-cylinder flow refinement, is a requirement, valves and piston bowl and intake exhaust port design optimization is essential. In order to reduce the time for design optimization cycle it is used Computational Fluid Dynamics (CFD). Being time consuming and highly costly caring out of experiment using flow bench testing this methods start to become less utilized. Air motion inside the intake manifold is one of the important factors, which govern the engine performance and emission of multi-cylinder diesel engines. Any cold flow study on IC is targeting the process of identifying and improving the fluid flow inside the ports and the combustion chamber. This is only the base for an optimization process targeting to increase the volume of air accessing the combustion space and to increase the turbulence of the air at the end of the compression stage. One of the first conclusions will be that the valve diameter is a fine tradeoff between the need for a bigger diameter involving a greater mass of air filling the cylinder, and the need of a smaller diameter in order to reduce the blind zone. Here there is room for optimization studies. The relative pressure indicates a suction effect coming from the moving piston. The more the shape of the inlet port is smoother and the diameter of the piston is bigger, the aerodynamic resistance of the geometry will be smaller so that the difference of inlet port pressure and the pressure near to piston face will be smaller. Here again there is enough room for more optimization studies.

Control method for turbocharged diesel engines having exhaust gas recirculation

DOEpatents

Kolmanovsky, Ilya V.; Jankovic, Mrdjan J; Jankovic, Miroslava

2000-03-14

A method of controlling the airflow into a compression ignition engine having an EGR and a VGT. The control strategy includes the steps of generating desired EGR and VGT turbine mass flow rates as a function of the desired and measured compressor mass airflow values and exhaust manifold pressure values. The desired compressor mass airflow and exhaust manifold pressure values are generated as a function of the operator-requested fueling rate and engine speed. The EGR and VGT turbine mass flow rates are then inverted to corresponding EGR and VGT actuator positions to achieve the desired compressor mass airflow rate and exhaust manifold pressure. The control strategy also includes a method of estimating the intake manifold pressure used in generating the EGR valve and VGT turbine positions.

An investigation of the use of discharge valves and an intake control for improving the performance of N.A.C.A. Roots type supercharger

NASA Technical Reports Server (NTRS)

Schey, Oscar W; Wilson, Ernest E

1929-01-01

This report presents the results of an analytical investigation on the practicability of using mechanically operated discharge valves in conjunction with a manually operated intake control for improving the performance of N. A. C. A. Roots type superchargers. These valves, which may be either of the oscillating or rotating type, are placed in the discharge opening of the supercharger and are so shaped and synchronized with the supercharger impellers that they do not open until the air has been compressed to the delivery pressure. The intake control limits the quantity of air compressed to engine requirements by permitting the excess air to escape from the compression chamber before compression begins. The percentage power saving and the actual horsepower saved were computed for altitudes from 0 to 20,000 feet. These computations are based on the pressure-volume cards for the conventional and the modified roots type superchargers and on the results of laboratory tests of the conventional type. The use of discharge valves shows a power saving of approximately 26 per cent at a critical altitude of 20,000 feet. In addition, these valves reduce the amplitude of the discharge pulsations and increase the volumetric efficiency. With slow-speed roots blowers operating at high-pressure differences even better results would be expected. For aircraft engine superchargers operating at high speeds these discharge valves increase the performance as above, but have the disadvantages of increasing the weight and of adding a high-speed mechanism to a simple machine. (author)

Experimental Investigation of Fuel-Reactivity Controlled Compression Ignition (RCCI) Combustion Mode in a Multi-Cylinder, Light-Duty Diesel Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cho, Kukwon; Curran, Scott; Prikhodko, Vitaly Y

2011-01-01

An experimental study was performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (RCCI) combustion mode utilizing dual-fuel approach in a light-duty, multi-cylinder diesel engine. In-cylinder fuel blending using port fuel injection of gasoline before intake valve opening (IVO) and early-cycle, direct injection of diesel fuel was used as the charge preparation and fuel blending strategy. In order to achieve the desired auto-ignition quality through the stratification of the fuel-air equivalence ratio ( ), blends of commercially available gasoline and diesel fuel were used. Engine experiments were performed at an engine speed of 2300rpm andmore » an engine load of 4.3bar brake mean effective pressure (BMEP). It was found that significant reduction in both nitrogen oxide (NOx) and particulate matter (PM) was realized successfully through the RCCI combustion mode even without applying exhaust gas recirculation (EGR). However, high carbon monoxide (CO) and hydrocarbon (HC) emissions were observed. The low combustion gas temperature during the expansion and exhaust processes seemed to be the dominant source of high CO emissions in the RCCI combustion mode. The high HC emissions during the RCCI combustion mode could be due to the increased combustion quenching layer thickness as well as the -stratification at the periphery of the combustion chamber. The slightly higher brake thermal efficiency (BTE) of the RCCI combustion mode was observed than the other combustion modes, such as the conventional diesel combustion (CDC) mode, and single-fuel, premixed charge compression ignition (PCCI) combustion mode. The parametric study of the RCCI combustion mode revealed that the combustion phasing and/or the peak cylinder pressure rise rate of the RCCI combustion mode could be controlled by several physical parameters premixed ratio (rp), intake swirl intensity, and start of injection (SOI) timing of directly injected fuel unlike other low temperature combustion (LTC) strategies.« less

System and method having multi-tube fuel nozzle with differential flow

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hughes, Michael John; Johnson, Thomas Edward; Berry, Jonathan Dwight

A system includes a multi-tube fuel nozzle with a fuel nozzle body and a plurality of tubes. The fuel nozzle body includes a nozzle wall surrounding a chamber. The plurality of tubes extend through the chamber, wherein each tube of the plurality of tubes includes an air intake portion, a fuel intake portion, and an air-fuel mixture outlet portion. The multi-tube fuel nozzle also includes a differential configuration of the air intake portions among the plurality of tubes.

Intensive liquid feeding of dairy calves with a medium crude protein milk replacer: Effects on performance, rumen, and blood parameters.

PubMed

de Paula, M R; Oltramari, C E; Silva, J T; Gallo, M P C; Mourão, G B; Bittar, C M M

2017-06-01

The objective of this study was to evaluate the effects of different liquid-feeding systems using a medium crude protein milk replacer on performance, rumen, and blood parameters. Thirty newborn Holstein calves were blocked according to birth weight and date of birth, and randomly distributed to different liquid-feeding systems: conventional (4 L/d), intensive (8 L/d), or step-up/step-down (wk 1, 4 L/d; wk 2 to 6, 8 L/d; wk 7 and 8, 4 L/d). The commercial milk replacer (12.5% solids, 20.2% crude protein, 15.6% fat) was fed twice daily (0700 and 1700 h) until calves were weaned, at 8 wk of age. Calves were individually housed in wood hutches, with free access to water and starter concentrate, and to hay only after weaning. They were followed through 10 wk of age. Milk replacer and starter intake were inversely affected by feeding system. After weaning, starter intake and hay intake were similar among feeding systems. Total dry matter intake was higher during the liquid-feeding period for calves on the intensive system compared to calves on the conventional system, but conventional feeding resulted in the highest dry matter intake after weaning. Feed efficiency was similar among feeding systems before and after weaning. Average body weight and daily gain were not affected by feeding system before or after weaning. During liquid feeding, diarrhea occurrence was lower for calves on the conventional system; however, when calves on the step-up/step-down system were fed lower volumes of liquid feed, diarrhea occurrence was similar to that of calves on the conventional system. Plasma concentrations of β-hydroxybutyrate were higher for calves on the conventional system, reflecting starter intake. Rumen pH, short-chain fatty acids, and N-NH 3 were not affected by feeding system. Feeding higher volumes of milk replacer with a medium crude protein content had no beneficial effect on the performance of calves up to 10 wk of age. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

30 CFR 75.341 - Direct-fired intake air heaters.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 75.341 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.341 Direct-fired intake air heaters. (a) If any system used to heat intake air malfunctions, the heaters affected shall switch...

2. INTAKES, S.A.R. 2 AND KELLER CREEK, EXHIBIT L, SANTA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. INTAKES, S.A.R. 2 AND KELLER CREEK, EXHIBIT L, SANTA ANA RIVER NO. 2 PROJECT, APR. 30, 1945. SCE drawing no. 523639 (sheet no. 10, for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, SAR-2 Intake, Redlands, San Bernardino County, CA

High School/High Tech: Promoting Career Exploration Technology for Youth with Learning Disabilities and Behavioral Disorders.

ERIC Educational Resources Information Center

Lemaire, Gail Schoen; Mallik, Kalisankar; Stoll, Bryan G.

2002-01-01

A model program to promote science, engineering, and technology careers and address academic and vocational needs of low-income youth with learning disabilities includes referral and intake processes and academic and career training and services. Of the 21 first-year participants, 13 were employed (7 in technology-related positions) or enrolled in…

Satiety and the role of μ-opioid receptors in the portal vein.

PubMed

De Vadder, Filipe; Gautier-Stein, Amandine; Mithieux, Gilles

2013-12-01

Mu-opioid receptors (MORs) are known to influence food intake at the brain level, through their involvement in the food reward system. MOR agonists stimulate food intake. On the other hand, MOR antagonists suppress food intake. MORs are also active in peripheral organs, especially in the small intestine where they control the gut motility. Recently, an indirect role in the control of food intake was ascribed to MORs in the extrinsic gastrointestinal neural system. MORs present in the neurons of the portal vein walls sense blood peptides released from the digestion of dietary protein. These peptides behave as MOR antagonists. Their MOR antagonist action initiates a gut-brain circuitry resulting in the induction of intestinal gluconeogenesis, a function controlling food intake. Thus, periportal MORs are a key mechanistic link in the satiety effect of protein-enriched diets. Copyright © 2013 Elsevier Ltd. All rights reserved.

Nutritional Requirements for Space Station Freedom Crews

NASA Technical Reports Server (NTRS)

Lane, Helen W.; Rice, Barbara L.; Wogan, Christine F. (Editor)

1992-01-01

The purpose of this report was to set preliminary nutritional requirements for crewmembers flying from 90 to 180 day missions on Space Station Freedom. Specific recommendations included providing crewmembers with in flight feedback on nutritional intake, weight and strength, and incorporating issues of energy intake, body weight, body composition, strength, and protein intake in the flight medicine program. Exercise must be considered an integral part of any plan to maintain nutritional status, especially those modes that stress the skeleton and maintain body weight. Nutrient intake, amount of exercise, and drugs ingested must be recorded daily; high priority should be given to development of fully automated record systems that minimize astronauts' effort. A system of nutritional supplements should be developed to provide a method for reducing intake deficits that become apparent. Finally, post flight monitoring should include bone density, muscle mass and function, and iron status at three and six months after landing.

Developing the remote sensing-based early warning system for monitoring TSS concentrations in Lake Mead.

PubMed

Imen, Sanaz; Chang, Ni-Bin; Yang, Y Jeffrey

2015-09-01

Adjustment of the water treatment process to changes in water quality is a focus area for engineers and managers of water treatment plants. The desired and preferred capability depends on timely and quantitative knowledge of water quality monitoring in terms of total suspended solids (TSS) concentrations. This paper presents the development of a suite of nowcasting and forecasting methods by using high-resolution remote-sensing-based monitoring techniques on a daily basis. First, the integrated data fusion and mining (IDFM) technique was applied to develop a near real-time monitoring system for daily nowcasting of the TSS concentrations. Then a nonlinear autoregressive neural network with external input (NARXNET) model was selected and applied for forecasting analysis of the changes in TSS concentrations over time on a rolling basis onward using the IDFM technique. The implementation of such an integrated forecasting and nowcasting approach was assessed by a case study at Lake Mead hosting the water intake for Las Vegas, Nevada, in the water-stressed western U.S. Long-term monthly averaged results showed no simultaneous impact from forest fire events on accelerating the rise of TSS concentration. However, the results showed a probable impact of a decade of drought on increasing TSS concentration in the Colorado River Arm and Overton Arm. Results of the forecasting model highlight the reservoir water level as a significant parameter in predicting TSS in Lake Mead. In addition, the R-squared value of 0.98 and the root mean square error of 0.5 between the observed and predicted TSS values demonstrates the reliability and application potential of this remote sensing-based early warning system in terms of TSS projections at a drinking water intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of GABAergic system on the inhibitory effect of ghrelin on food intake in neonatal chicks.

PubMed

Jonaidi, H; Abbassi, L; Yaghoobi, M M; Kaiya, H; Denbow, D M; Kamali, Y; Shojaei, B

2012-06-27

Ghrelin is a gut-brain peptide that has a stimulatory effect on food intake in mammals. In contrast, this peptide decreases food intake in neonatal chicks when injected intracerebroventricularly (ICV). In mammals, neuropeptide Y (NPY) mediates the orexigenic effect of ghrelin whereas in chicks it appears that corticotrophin releasing factor (CRF) is partially involved in the inhibitory effect of ghrelin on food intake. Gamma aminobutyric acid (GABA) has a stimulatory effect on food intake in mammals and birds. In this study we investigated whether the anorectic effect of ghrelin is mediated by the GABAergic system. In Experiment 1, 3h-fasted chicks were given an ICV injection of chicken ghrelin and picrotoxin, a GABA(A) receptors antagonist. Picrotoxin decreased food intake compared to the control chicks indicating a stimulatory effect of GABA(A) receptors on food intake. However, picrotoxin did not alter the inhibitory effect of ghrelin on food intake. In Experiment 2, THIP hydrochloride, a GABA(A) receptor agonist, was used in place of picrotoxin. THIP hydrochloride appeared to partially attenuate the decrease in food intake induced by ghrelin at 30 min postinjection. In Experiment 3, the effect of ICV injection of chicken ghrelin on gene expression of glutamate decarboxylase (GAD)(1) and GAD(2), GABA synthesis enzymes in the brain stem including hypothalamus, was investigated. The ICV injection of chicken ghrelin significantly reduced GAD(2) gene expression. These findings suggest that ghrelin may decrease food intake in neonatal chicks by reducing GABA synthesis and thereby GABA release within brain feeding centers. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Comparison of Virtual Nutri Plus® and Dietpro 5i® software systems for the assessment of nutrient intake before and after Roux-en-Y gastric bypass

PubMed Central

Marques da Silva, Mariane; Sala, Priscila Campos; Cardinelli, Camila Siqueira; Torrinhas, Raquel Suzana; Waitzberg, Dan Linetzky

2014-01-01

OBJECTIVES: The assessment of nutritional intake before and after bariatric surgery assists in identifying eating disorders, nutritional deficiencies and weight loss/maintenance. The 7-day record is the gold standard for such an assessment and is interpreted using specialized software. This study sought to compare the Virtual Nutri Plus® and Dietpro 5i® software systems in assessing nutrient intake in obese patients with type 2 diabetes mellitus who underwent a Roux-en-Y gastric bypass. METHODS: Nutritional intake was assessed in 10 obese women with type 2 diabetes mellitus before and 3 months after Roux-en-Y gastric bypass. The 7-day record was used to assess food intake and then, the Virtual Nutri Plus® and Dietpro 5i® software systems were used to calculate calorie, macronutrient and micronutrient intake based on validated food chemical composition databases. Clinicaltrials.gov: NCT01251016. RESULTS: During the preoperative period, deficits in the ingestion of total fiber and 15 out of 22 estimated micronutrients were observed when using the Virtual Nutri Plus®, compared to deficiencies in total fiber and 4 micronutrients when using the Dietpro 5i®. During the postoperative period, both the Virtual Nutri Plus® and Dietpro 5i® systems detected deficits in the ingestion of total fiber, carbohydrates and 19 micronutrients, but only the Virtual Nutri Plus® detected deficits in complex B vitamins (except B12) and minerals. CONCLUSION: Virtual Nutri Plus® was more sensitive than Dietpro 5i® for the identification of deficits in nutrient intake in obese, type 2 diabetes mellitus patients undergoing Roux-en-Y gastric bypass. PMID:25518027

Mechanisms and implications of a type IV functional response for short-term intake rate of dry matter in large mammalian herbivores.

PubMed

Mezzalira, Jean C; Bonnet, Olivier J F; Carvalho, Paulo C de F; Fonseca, Lidiane; Bremm, Carolina; Mezzalira, Carlos C; Laca, Emilio A

2017-09-01

The functional response (i.e. the relationship between consumers' intake rate and resource density) is central in plant-herbivore interactions. Its shape and the biological processes leading to it have significant implications for both foraging theory and ecology of grazing systems. A type IV functional response (i.e. dome-shaped relationship) of short-term intake rate of dry matter (intake while grazing) has rarely been reported for large herbivores and the conditions that can lead to it are poorly understood. We report a type IV functional response observed in heifers grazing monocultures of Cynodon sp. and Avena strigosa. The mechanisms and consequences of this type of functional response for grazed system dynamics are discussed. Intake rate was higher at intermediate than at short or tall sward heights in both grass species. The type IV functional response resulted from changes in bite mass instead of a longer time needed to encounter and process bites. Thus, the decrease of intake rate of dry matter in tall swards is not explained by a shift from process 3 (potential bites are concentrated and apparent) to process 2 (potential bites are apparent but dispersed, Spalinger & Hobbs 1992). Bite mass was smaller in tall than in intermediate swards due to a reduction of bite volume possibly caused by the greater proportion of stem and sheath acting as a physical barrier to bite formation. It is generally accepted that potential bites are abundant and apparent in most grassland and meadow systems, as they were in the present experiments. Therefore, a type IV response of intake rate not directly related to digestive constraints may determine the dynamics of intake and defoliation under a much larger set of conditions than previously thought. These results have implications for foraging theory and stability of grazing systems. For example, if animals prefer patches of intermediate stature that yield the highest intake rate, grazing should lead to the widely observed bimodal distribution of plant mass per unit area, even when tall patches are not of significantly lower digestive quality than the pasture average. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pamminger, Michael; Sevik, James; Scarcelli, Riccardo

The compression ratio is a strong lever to increase the efficiency of an internal combustion engine. However, among others, it is limited by the knock resistance of the fuel used. Natural gas shows a higher knock resistance compared to gasoline, which makes it very attractive for use in internal combustion engines. The current paper describes the knock behavior of two gasoline fuels, and specific incylinder blend ratios with one of the gasoline fuels and natural gas. The engine used for these investigations is a single cylinder research engine for light duty application which is equipped with two separate fuel systems.more » Both fuels can be used simultaneously which allows for gasoline to be injected into the intake port and natural gas to be injected directly into the cylinder to overcome the power density loss usually connected with port fuel injection of natural gas. Adding natural gas at wide open throttle helps to reduce knock mitigating measures and increases the efficiency and power density compared to the other gasoline type fuels with lower knock resistance. The used methods, knock intensity and number of pressure waves, do not show significant differences in knock behavior for the natural gas - gasoline blends compared to the gasoline type fuels. A knock integral was used to describe the knock onset location of the fuels tested. Two different approaches were used to determine the experimental knock onset and were compared to the knock onset delivered by the knock integral (chemical knock onset). The gasoline type fuels show good agreement between chemical and experimental knock onset. However, the natural gas -gasoline blends show higher discrepancies comparing chemical and experimental knock onset.« less

Nutritional status assessment in semiclosed environments: ground-based and space flight studies in humans

NASA Technical Reports Server (NTRS)

Smith, S. M.; Davis-Street, J. E.; Rice, B. L.; Nillen, J. L.; Gillman, P. L.; Block, G.

2001-01-01

Adequate nutrition is critical during long-term spaceflight, as is the ability to easily monitor dietary intake. A comprehensive nutritional status assessment profile was designed for use before, during and after flight. It included assessment of both dietary intake and biochemical markers of nutritional status. A spaceflight food-frequency questionnaire (FFQ) was developed to evaluate intake of key nutrients during spaceflight. The nutritional status assessment protocol was evaluated during two ground-based closed-chamber studies (60 and 91 d; n = 4/study), and was implemented for two astronauts during 4-mo stays on the Mir space station. Ground-based studies indicated that the FFQ, administered daily or weekly, adequately estimated intake of key nutrients. Chamber subjects maintained prechamber energy intake and body weight. Astronauts tended to eat 40--50% of WHO-predicted energy requirements, and lost >10% of preflight body mass. Serum ferritin levels were lower after the chamber stays, despite adequate iron intake. Red blood cell folate concentrations were increased after the chamber studies. Vitamin D stores were decreased by > 40% on chamber egress and after spaceflight. Mir crew members had decreased levels of most nutritional indices, but these are difficult to interpret given the insufficient energy intake and loss of body mass. Spaceflight food systems can provide adequate intake of macronutrients, although, as expected, micronutrient intake is a concern for any closed or semiclosed food system. These data demonstrate the utility and importance of nutritional status assessment during spaceflight and of the FFQ during extended-duration spaceflight.

Pseudo-shock waves and their interactions in high-speed intakes

NASA Astrophysics Data System (ADS)

Gnani, F.; Zare-Behtash, H.; Kontis, K.

2016-04-01

In an air-breathing engine the flow deceleration from supersonic to subsonic conditions takes places inside the isolator through a gradual compression consisting of a series of shock waves. The wave system, referred to as a pseudo-shock wave or shock train, establishes the combustion chamber entrance conditions, and therefore influences the performance of the entire propulsion system. The characteristics of the pseudo-shock depend on a number of variables which make this flow phenomenon particularly challenging to be analysed. Difficulties in experimentally obtaining accurate flow quantities at high speeds and discrepancies of numerical approaches with measured data have been readily reported. Understanding the flow physics in the presence of the interaction of numerous shock waves with the boundary layer in internal flows is essential to developing methods and control strategies. To counteract the negative effects of shock wave/boundary layer interactions, which are responsible for the engine unstart process, multiple flow control methodologies have been proposed. Improved analytical models, advanced experimental methodologies and numerical simulations have allowed a more in-depth analysis of the flow physics. The present paper aims to bring together the main results, on the shock train structure and its associated phenomena inside isolators, studied using the aforementioned tools. Several promising flow control techniques that have more recently been applied to manipulate the shock wave/boundary layer interaction are also examined in this review.

The ghrelin signalling system is involved in the consumption of sweets.

PubMed

Landgren, Sara; Simms, Jeffrey A; Thelle, Dag S; Strandhagen, Elisabeth; Bartlett, Selena E; Engel, Jörgen A; Jerlhag, Elisabet

2011-03-23

The gastric-derived orexigenic peptide ghrelin affects brain circuits involved in energy balance as well as in reward. Indeed, ghrelin activates an important reward circuit involved in natural- as well as drug-induced reward, the cholinergic-dopaminergic reward link. It has been hypothesized that there is a common reward mechanism for alcohol and sweet substances in both animals and humans. Alcohol dependent individuals have higher craving for sweets than do healthy controls and the hedonic response to sweet taste may, at least in part, depend on genetic factors. Rat selectively bred for high sucrose intake have higher alcohol consumption than non-sucrose preferring rats and vice versa. In the present study a group of alcohol-consuming individuals selected from a population cohort was investigated for genetic variants of the ghrelin signalling system in relation to both their alcohol and sucrose consumption. Moreover, the effects of GHS-R1A antagonism on voluntary sucrose-intake and operant self-administration, as well as saccharin intake were investigated in preclinical studies using rodents. The effects of peripheral grelin administration on sucrose intake were also examined. Here we found associations with the ghrelin gene haplotypes and increased sucrose consumption, and a trend for the same association was seen in the high alcohol consumers. The preclinical data show that a GHS-R1A antagonist reduces the intake and self-administration of sucrose in rats as well as saccharin intake in mice. Further, ghrelin increases the intake of sucrose in rats. Collectively, our data provide a clear indication that the GHS-R1A antagonists reduces and ghrelin increases the intake of rewarding substances and hence, the central ghrelin signalling system provides a novel target for the development of drug strategies to treat addictive behaviours.

The Ghrelin Signalling System Is Involved in the Consumption of Sweets

PubMed Central

Landgren, Sara; Simms, Jeffrey A.; Thelle, Dag S.; Strandhagen, Elisabeth; Bartlett, Selena E.; Engel, Jörgen A.; Jerlhag, Elisabet

2011-01-01

The gastric-derived orexigenic peptide ghrelin affects brain circuits involved in energy balance as well as in reward. Indeed, ghrelin activates an important reward circuit involved in natural- as well as drug-induced reward, the cholinergic-dopaminergic reward link. It has been hypothesized that there is a common reward mechanism for alcohol and sweet substances in both animals and humans. Alcohol dependent individuals have higher craving for sweets than do healthy controls and the hedonic response to sweet taste may, at least in part, depend on genetic factors. Rat selectively bred for high sucrose intake have higher alcohol consumption than non-sucrose preferring rats and vice versa. In the present study a group of alcohol-consuming individuals selected from a population cohort was investigated for genetic variants of the ghrelin signalling system in relation to both their alcohol and sucrose consumption. Moreover, the effects of GHS-R1A antagonism on voluntary sucrose- intake and operant self-administration, as well as saccharin intake were investigated in preclinical studies using rodents. The effects of peripheral grelin administration on sucrose intake were also examined. Here we found associations with the ghrelin gene haplotypes and increased sucrose consumption, and a trend for the same association was seen in the high alcohol consumers. The preclinical data show that a GHS-R1A antagonist reduces the intake and self-administration of sucrose in rats as well as saccharin intake in mice. Further, ghrelin increases the intake of sucrose in rats. Collectively, our data provide a clear indication that the GHS-R1A antagonists reduces and ghrelin increases the intake of rewarding substances and hence, the central ghrelin signalling system provides a novel target for the development of drug strategies to treat addictive behaviours. PMID:21448464

78 FR 53196 - Agency Information Collection (Principles of Excellence Complaint System Intake); Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-28

... (Principles of Excellence Complaint System Intake); Comment Request AGENCY: Veterans Benefits Administration, Department of Veterans Affairs. ACTION: Notice. SUMMARY: The Veterans Benefits Administration (VBA) is announcing an opportunity for public comment on the proposed collection of certain information by the agency...

Bonneville Powerhouse 2 Fish Guidance Efficiency Studies: CFD Model of the Forebay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rakowski, Cynthia L.; Serkowski, John A.; Richmond, Marshall C.

2012-07-01

In ongoing work, U.S. Army Corps of Engineers, Portland District (CENWP) is seeking to better understand and improve the conditions within the Bonneville Powerhouse 2 (B2) turbine intakes to improve survival of downstream migrant salmonid smolt. In this study, the existing B2 forebay computational fluid dynamics (CFD) model was modified to include a more detailed representation of all B2 turbine intakes. The modified model was validated to existing field-measured forebay ADCP velocities. The initial CFD model scenarios tested a single project operation and the impact of adding the Behavior Guidance System (BGS) or Corner Collector. These structures had impacts onmore » forebay flows. Most notable was that the addition of the BGS and Corner Collector reduced the lateral extent of the recirculation areas on the Washington shore and Cascade Island and reduced the flow velocity parallel to the powerhouse in front of Units 11 and 12. For these same cases, at the turbine intakes across the powerhouse, there was very little difference in the flow volume into the gatewell for the clean forebay, and the forebay with the BGS in place and/or the Corner Collector operating. The largest differences were at Units 11 to 13. The CFD model cases testing the impact of the gatewell slot fillers showed no impact to the forebay flows, but large differences within the gatewells. With the slot fillers, the flow above the standard traveling screen and into the gatewell increased (about 100 cfs at each turbine intake) and the gap flow decreased across the powerhouse for all cases. The increased flow up the gatewell was further enhanced with only half the units operating. The flow into the gatewell slot was increased about 35 cfs for each bay of each intake across the powerhouse; this change was uniform across the powerhouse. The flows in the gatewell of Unit 12, the most impacted unit for the scenarios, was evaluated. In front of the vertical barrier screen, the CFD model with slot fillers showed reduced the maximum velocities (in spite of the increased the flow into the gatewell), and decreased the area of recirculation. The area near the VBS exceeding the normal velocity criteria of 1 ft/s was reduced and the flows were more balanced.« less

High Temperature Degradation of Advanced Thermal and Environmental Barrier Coatings (TEBCs) by CaO-MgO-Al2O3-SiO2 (CMAS)

NASA Technical Reports Server (NTRS)

Costa, Gustavo; Zhu, Dongming

2017-01-01

There is increasing interest in the degradation studies of thermal and environmental barrier coatings (TEBCs) of gas turbines by molten CaO-MgO-Al2O3-SiO2 (CMAS). CMAS minerals are usually referred as silica-containing sand dust and volcano ash materials that are carried by the intake air into gas turbines, e.g. aircraft engines. The low-melting deposits react at high temperatures (1000C) with the coating materials. This causes degradation and accelerated coating failure of the static and rotating components of the turbine engines. We discuss some preliminary results of the reactions between CMAS and Rare-Earth (RE Y, Yb, Dy, Gd, Nd and Sm) oxide stabilized ZrO2 or HfO2 systems, and the stability of the resulting oxides and silicates. Plasma sprayed hollow tube samples (outer diameter 4.7 mm, wall thickness 0.76 mm and 26 mm height) were half filled with CMAS powder, wrapped and sealed with platinum foil, and heat- treated at 1310 C for 5h. Samples were characterized by differential scanning calorimetry, X-ray diffraction and cross section electron microscopy analysis.

Popular Nutrition-Related Mobile Apps: A Feature Assessment.

PubMed

Franco, Rodrigo Zenun; Fallaize, Rosalind; Lovegrove, Julie A; Hwang, Faustina

2016-08-01

A key challenge in human nutrition is the assessment of usual food intake. This is of particular interest given recent proposals of eHealth personalized interventions. The adoption of mobile phones has created an opportunity for assessing and improving nutrient intake as they can be used for digitalizing dietary assessments and providing feedback. In the last few years, hundreds of nutrition-related mobile apps have been launched and installed by millions of users. This study aims to analyze the main features of the most popular nutrition apps and to compare their strategies and technologies for dietary assessment and user feedback. Apps were selected from the two largest online stores of the most popular mobile operating systems-the Google Play Store for Android and the iTunes App Store for iOS-based on popularity as measured by the number of installs and reviews. The keywords used in the search were as follows: calorie(s), diet, diet tracker, dietician, dietitian, eating, fit, fitness, food, food diary, food tracker, health, lose weight, nutrition, nutritionist, weight, weight loss, weight management, weight watcher, and ww calculator. The inclusion criteria were as follows: English language, minimum number of installs (1 million for Google Play Store) or reviews (7500 for iTunes App Store), relation to nutrition (ie, diet monitoring or recommendation), and independence from any device (eg, wearable) or subscription. A total of 13 apps were classified as popular for inclusion in the analysis. Nine apps offered prospective recording of food intake using a food diary feature. Food selection was available via text search or barcode scanner technologies. Portion size selection was only textual (ie, without images or icons). All nine of these apps were also capable of collecting physical activity (PA) information using self-report, the global positioning system (GPS), or wearable integrations. Their outputs focused predominantly on energy balance between dietary intake and PA. None of these nine apps offered features directly related to diet plans and motivational coaching. In contrast, the remaining four of the 13 apps focused on these opportunities, but without food diaries. One app-FatSecret-also had an innovative feature for connecting users with health professionals, and another-S Health-provided a nutrient balance score. The high number of installs indicates that there is a clear interest and opportunity for diet monitoring and recommendation using mobile apps. All the apps collecting dietary intake used the same nutrition assessment method (ie, food diary record) and technologies for data input (ie, text search and barcode scanner). Emerging technologies, such as image recognition, natural language processing, and artificial intelligence, were not identified. None of the apps had a decision engine capable of providing personalized diet advice.

Investigation of the Intake of a Stationary Gas Turbine to Prevent Ice Formation

NASA Astrophysics Data System (ADS)

Tramposch, Andreas; Molnár, Vojtech; Ridzoň, František

2011-12-01

Repeated emergency shutdowns of a stationary gas turbine under conditions of sub-freezing temperatures and moist air have led to the suspicion that ice formation in the intake channel and compressor may be a contributing factor. To understand the reason, why the installed ice protection system is not effective, a numerical investigation of the intake channel with the installed hot air ice protection system has been performed. It is shown that mixing of hot air with cold outside air is incomplete, explaining the ice accretion.

77 FR 34927 - National Pollutant Discharge Elimination System-Proposed Regulations To Establish Requirements...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-12

...-5] RIN 2040-AE95 National Pollutant Discharge Elimination System--Proposed Regulations To Establish Requirements for Cooling Water Intake Structures at Existing Facilities; Notice of Data Availability Related to... availability. SUMMARY: On April 20, 2011, EPA published proposed standards for cooling water intake structures...

[Good practices and techniques for prevention of accidents at work and occupational diseases. New database of Inail].

PubMed

Bindi, L; Ossicini, A

2007-01-01

The project "The publication of good practices and good techniques for prevention" is one the priorities of nail. This computerized system for the collection of good practices and standards of Good Technology is aimed to health and safety of workers. The basic objective of the database is to provide a valuable tool, usable, dynamic and implemented, in order to facilitate and direct the access to BP and BT it by people responsible for SSL. At the same time constitutes a tool strategically important for enterprises (especially SMEs) in terms of technological innovation and competitiveness, related to the prevention, safety and health of workers. The realization of this project has involved many of the professionals (chemists, engineers, doctors, biologists, geologists, etc.), and everyone gives his intake of qualified professional competence.

Efficiency bounds for nonequilibrium heat engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mehta, Pankaj; Polkovnikov, Anatoli, E-mail: asp@bu.edu

2013-05-15

We analyze the efficiency of thermal engines (either quantum or classical) working with a single heat reservoir like an atmosphere. The engine first gets an energy intake, which can be done in an arbitrary nonequilibrium way e.g. combustion of fuel. Then the engine performs the work and returns to the initial state. We distinguish two general classes of engines where the working body first equilibrates within itself and then performs the work (ergodic engine) or when it performs the work before equilibrating (non-ergodic engine). We show that in both cases the second law of thermodynamics limits their efficiency. For ergodicmore » engines we find a rigorous upper bound for the efficiency, which is strictly smaller than the equivalent Carnot efficiency. I.e. the Carnot efficiency can be never achieved in single reservoir heat engines. For non-ergodic engines the efficiency can be higher and can exceed the equilibrium Carnot bound. By extending the fundamental thermodynamic relation to nonequilibrium processes, we find a rigorous thermodynamic bound for the efficiency of both ergodic and non-ergodic engines and show that it is given by the relative entropy of the nonequilibrium and initial equilibrium distributions. These results suggest a new general strategy for designing more efficient engines. We illustrate our ideas by using simple examples. -- Highlights: ► Derived efficiency bounds for heat engines working with a single reservoir. ► Analyzed both ergodic and non-ergodic engines. ► Showed that non-ergodic engines can be more efficient. ► Extended fundamental thermodynamic relation to arbitrary nonequilibrium processes.« less

Performance, emissions, and physical characteristics of a rotating combustion aircraft engine, supplement A

NASA Technical Reports Server (NTRS)

Lamping, R. K.; Manning, I.; Myers, D.; Tjoa, B.

1980-01-01

Testing was conducted using the basic RC2-75 engine, to which several modifications were incorporated which were designed to reduce the hydrocarbon emissions and reduce the specific fuel consumption. The modifications included close-in surface gap spark plugs, increased compression ratio rotors, and provisions for utilizing either side or peripheral intake ports, or a combination of the two if required. The proposed EPA emissions requirements were met using the normal peripheral porting. The specific fuel economy demonstrated for the modified RC2-75 was 283 g/kW-hr at 75% power and 101 brake mean effective pressure (BMEP) and 272.5 g/kW-hr at 75% power and 111 BMEP. The latter would result from rating the engine for takeoff at 285 hp and 5500 rpm, instead of 6000 rpm.

Performance and Exhaust Emissions in a Natural-Gas Fueled Dual-Fuel Engine

NASA Astrophysics Data System (ADS)

Shioji, Masahiro; Ishiyama, Takuji; Ikegami, Makoto; Mitani, Shinichi; Shibata, Hiroaki

In order to establish the optimum fueling in a natural gas fueled dual fuel engine, experiments were done for some operational parameters on the engine performances and the exhaust emissions. The results show that the pilot fuel quantity should be increased and its injection timing should be advanced to suppress unburned hydrocarbon emission in the middle and low output range, while the quantity should be reduced and the timing retarded to avoid onset of knock at high loads. Unburned hydrocarbon emission and thermal efficiency are improved by avoiding too lean natural gas mixture by restricting intake charge air. However, the improvement is limited because the ignition of pilot fuel deteriorates with excessive throttling. It is concluded that an adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sevik, James; Pamminger, Michael; Wallner, Thomas

Interest in natural gas as an alternative fuel source to petroleum fuels for light-duty vehicle applications has increased due to its domestic availability and stable price compared to gasoline. With its higher hydrogen-to-carbon ratio, natural gas has the potential to reduce engine out carbon dioxide emissions, which has shown to be a strong greenhouse gas contributor. For part-load conditions, the lower flame speeds of natural gas can lead to an increased duration in the inflammation process with traditional port-injection. Direct-injection of natural gas can increase in-cylinder turbulence and has the potential to reduce problems typically associated with port-injection of naturalmore » gas, such as lower flame speeds and poor dilution tolerance. A study was designed and executed to investigate the effects of direct-injection of natural gas at part-load conditions. Steady-state tests were performed on a single-cylinder research engine representative of current gasoline direct-injection engines. Tests were performed with direct-injection in the central and side location. The start of injection was varied under stoichiometric conditions in order to study the effects on the mixture formation process. In addition, exhaust gas recirculation was introduced at select conditions in order to investigate the dilution tolerance. Relevant combustion metrics were then analyzed for each scenario. Experimental results suggest that regardless of the injector location, varying the start of injection has a strong impact on the mixture formation process. Delaying the start of injection from 300 to 120°CA BTDC can reduce the early flame development process by nearly 15°CA. While injecting into the cylinder after the intake valves have closed has shown to produce the fastest combustion process, this does not necessarily lead to the highest efficiency, due to increases in pumping and wall heat losses. When comparing the two injection configurations, the side location shows the best performance in terms of combustion metrics and efficiencies. For both systems, part-load dilution tolerance is affected by the injection timing, due to the induced turbulence from the gaseous injection event. CFD simulation results have shown that there is a fundamental difference in how the two injection locations affect the mixture formation process. Delayed injection timing increases the turbulence level in the cylinder at the time of the spark, but reduces the available time for proper mixing. Side injection delivers a gaseous jet that interacts more effectively with the intake induced flow field, and this improves the engine performance in terms of efficiency.« less

Sodium and Its Role in Cardiovascular Disease – The Debate Continues

PubMed Central

Kong, Yee Wen; Baqar, Sara; Jerums, George; Ekinci, Elif I.

2016-01-01

Guidelines have recommended significant reductions in dietary sodium intake to improve cardiovascular health. However, these dietary sodium intake recommendations have been questioned as emerging evidence has shown that there is a higher risk of cardiovascular disease with a low sodium diet, including in individuals with type 2 diabetes. This may be related to the other pleotropic effects of dietary sodium intake. Therefore, despite recent review of dietary sodium intake guidelines by multiple organizations, including the dietary guidelines for Americans, American Diabetes Association, and American Heart Association, concerns about the impact of the degree of sodium restriction on cardiovascular health continue to be raised. This literature review examines the effects of dietary sodium intake on factors contributing to cardiovascular health, including left ventricular hypertrophy, heart rate, albuminuria, rennin–angiotensin–aldosterone system activation, serum lipids, insulin sensitivity, sympathetic nervous system activation, endothelial function, and immune function. In the last part of this review, the association between dietary sodium intake and cardiovascular outcomes, especially in individuals with diabetes, is explored. Given the increased risk of cardiovascular disease in individuals with diabetes and the increasing incidence of diabetes worldwide, this review is important in summarizing the recent evidence regarding the effects of dietary sodium intake on cardiovascular health, especially in this population. PMID:28066329

2. View toward east, west face ("D" wall) of perimeter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. View toward east, west face ("D" wall) of perimeter acquisition radar building with subterranean power plants diesel engine intake (the smaller column) and exhaust seen in foreground. Behind the globe is the very low frequency (VLP) antenna - Stanley R. Mickelsen Safeguard Complex, Perimeter Acquisition Radar Building, Limited Access Area, between Limited Access Patrol Road & Service Road A, Nekoma, Cavalier County, ND

Leptin receptor-deficient obese Zucker rats reduce their food intake in response to a systemic supply of calories from glucose.

PubMed

Gilbert, Marc; Magnan, Christophe; Turban, Sophie; André, Jocelyne; Guerre-Millo, Michèle

2003-02-01

It has been established that leptin exerts a negative control on food intake, allowing one to maintain stable caloric intake over time. The aim of the present study was to investigate whether leptin regulates food intake when a supply of calories is provided by the systemic route. Experiments were carried out in leptin receptor-deficient obese fa/fa rats and lean Fa/fa controls. In both groups, 48 h of glucose infusion reduced food intake in proportion to caloric supply, resulting in virtually no change in total caloric intake as compared to before the infusion. This hypophagic response was reproduced without adding systemic calories, but by increasing glucose and insulin concentrations specifically in the brain through carotid artery infusion. Concomitant intracerebroventricular administration of 5-(tetradecyloxy)-2-furoic acid, an acetyl CoA carboxylase inhibitor that precludes malonyl-CoA synthesis, abolished the restriction of feeding in carotid-infused lean and obese rats. These data indicate that a supply of calories via glucose infusion induces a hypophagic response independent of leptin signaling in the rat, and support the hypothesis that a rise in central malonyl-CoA, triggered by increased glucose and insulin concentrations, participates in this adaptation. This process could contribute to the limiting of hyperphagia, primarily when leptin signaling is altered, as in the obese state.

Adverse systemic arterial function in patients with selenium deficiency.

PubMed

Chan, Y-H; Siu, C-W; Yiu, K-H; Chan, H-T; Li, S-W; Tam, S; Cheung, B M; Lau, C-P; Lam, T H; Tse, H-F

2012-01-01

Experimental studies have shown that selenium is involved in the synthesis of selenoproteins which might contribute to cardiovascular protection. However, the relationship between selenium deficiency and vascular function in clinical context remains unknown. To investigate for any relationship between selenium deficiency and systemic arterial function in patients with high risk of vascular events. Cross-sectional study. 306 consecutive patients with high risk for cardiovascular events (coronary artery disease 35%, acute/ recurrent ischemic stroke 40%, diabetes mellitus 54%) followed up at internal medicine outpatient clinics. Non-invasive brachial-ankle pulse wave velocity (PWV) was determined using vascular profiling system (VP-2000). Long-term intake of selenium was determined by a validated food frequency questionnaire. Mean daily selenium intake was 59.5 ± 52.1 mcg/day, and mean PWV was 1782.4 ± 418.4 cm/s. Patients with selenium intake <10th percentile had significantly higher PWV as compared to patients with intake ≥ 10th percentile (1968.2 ± 648.9 cm/s versus 1762.2 ± 381.6 cm/s, P=0.010). After adjusting for potential confounders including age, gender, history of hypertension, hyperlipidemia, diabetes and cardiovascular disease, smoking status, use of cardiovascular medications, waist-hip ratio, education/ financial status, physical activity, calorie intake and intake of antioxidant vitamins, deficient selenium intake <10th percentile remained independently predictive of increased PWV by +363.4 cm/s [95% CI: 68.1 to 658.6, P=0.016, relative increase 21%]. Selenium deficiency is associated with adverse arterial function in patients with high risk for vascular events.

Reconstruction of long-lived radionuclide intakes for Techa riverside residents: 137Cs.

PubMed

Tolstykh, E I; Degteva, M O; Peremyslova, L M; Shagina, N B; Vorobiova, M I; Anspaugh, L R; Napier, B A

2013-05-01

Radioactive contamination of the Techa River (Southern Urals, Russia) occurred from 1949-1956 due to routine and accidental releases of liquid radioactive wastes from the Mayak Production Association. The long-lived radionuclides in the releases were Sr and Cs. Contamination of the components of the Techa River system resulted in chronic external and internal exposure of about 30,000 residents of riverside villages. Data on radionuclide intake with diet are used to estimate internal dose in the Techa River Dosimetry System (TRDS), which was elaborated for the assessment of radiogenic risk for Techa Riverside residents. The Sr intake function was recently improved, taking into account the recently available archival data on radionuclide releases and in-depth analysis of the extensive data on Sr measurements in Techa Riverside residents. The main purpose of this paper is to evaluate the dietary intake of Cs by Techa Riverside residents. The Cs intake with river water used for drinking was reconstructed on the basis of the Sr intake-function and the concentration ratio Cs-to-Sr in river water. Intake via Cs transfer from floodplain soil to grass and cows' milk was evaluated for the first time. As a result, the maximal Cs intake level was indicated near the site of releases in upper-Techa River settlements (8,000-9,000 kBq). For villages located on the lower Techa River, the Cs intake was significantly less (down to 300 kBq). Cows' milk was the main source of Cs in diet in the upper-Techa River region.

OTEC gas desorption studies

NASA Astrophysics Data System (ADS)

Chen, F. C.; Golshani, A.

1982-02-01

Experiments on deaeration in packed columns and barometric intake systems, and with hydraulic air compression for open-cycle OTEC systems are reported. A gas desorption test loop consisting of water storage tanks, a vacuum system, a liquid recirculating system, an air supply, a column test section, and two barometric leg test sections was used to perform the tests. The aerated water was directed through columns filled with either ceramic Raschig rings or plastic pall rings, and the system vacuum pressure, which drives the deaeration process, was found to be dependent on water velocity and intake pipe height. The addition of a barometric intake pipe increased the deaeration effect 10%, and further tests were run with lengths of PVC pipe as potential means for noncondensibles disposal through hydraulic air compression. Using the kinetic energy from the effluent flow to condense steam in the noncondensible stream improved the system efficiency.

Contrasting effects of systemic and central sibutramine administration on the intake of a palatable diet in the rat.

PubMed

Pratt, Wayne E; Connolly, Megan E

2010-10-22

Sibutramine hydrochloride monohydrate is the only centrally active weight-modifying agent currently approved by the FDA for long-term use in the treatment of obesity. Systemic sibutramine treatment has been shown to reduce food intake in humans and rodent models in a manner that is consistent with the enhancement of satiety mechanisms. Although it is generally assumed that the hypophagic effects of the drug are mediated by actions within the brain, the locus or loci of these effects remains unclear. These experiments compared the effects of systemic and intracranial injections of sibutramine on the intake of a palatable diet in non-deprived animals. Consistent with prior reports, systemic injections of sibutramine hydrochloride (at 0, 0.5, 1.0, or 3.0mg/kg sibutramine i.p.) dose-dependently reduced feeding on a high fat/high sucrose diet across a 2-h feeding session, but did not alter water intake or locomotor activity. In contrast, bilateral injections of sibutramine (at 0.0, 2.0, 4.0 and 10.0μg/0.5μl/side) into either the paraventricular nucleus of the hypothalamus (PVN) or the medial nucleus accumbens shell (ACb) significantly and dose-dependently increased food intake of the sweetened fat diet. ACb treatment also modestly inhibited locomotor behavior; intracranial injections had no effect on water consumption. These experiments are the first to suggest that sibutramine treatment may have distinct actions upon separate neural circuits that modulate food intake behavior in the rat. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Factors associated with risky sun exposure behaviors among operating engineers.

PubMed

Duffy, Sonia A; Choi, Seung Hee; Hollern, Rachael; Ronis, David L

2012-09-01

The objective of this study was to determine the factors associated with sun exposure behaviors among Operating Engineers (heavy equipment operators). Operating Engineers (N = 498) were asked to complete a cross-sectional survey. Linear and logistic regression analyses were used to determine health behavioral, perceptional, and demographic factors associated with sun exposure behavior (sun burns, blistering, use of sunscreen, and interest in sun protection services). Almost half reported two or more sunburns/summer and the median times blistering was 2 with a range of 0-100. About one-third never used sun block, while just over one-third rarely used sun block. Almost one-quarter were interested in sun protection guidance. Multivariate analyses showed that perceptions of skin type, alcohol problems, fruit intake, BMI, sleep quality, age, sex, and race were significantly associated with at least one of the outcome variables (P < 0.05). Operating Engineers are at high risk for skin cancer due to high rates of exposure to ultraviolet light and low rates of sun block use. Subgroups of Operating Engineers are particularly at risk for sun damage. Interventions are needed to decrease sun exposure among Operating Engineers. Copyright © 2012 Wiley Periodicals, Inc.

The effect of chine tires on nose gear water-spray characteristics of a twin engine airplane

NASA Technical Reports Server (NTRS)

Yager, T. J.; Stubbs, S. M.; Mccarty, J. L.

1975-01-01

An experimental investigation was performed to evaluate the effectiveness of nose gear chine tires in eliminating or minimizing the engine spray ingestion problem encountered on several occasions by the Merlin 4, a twin-engine propjet airplane. A study of the photographic and television coverage indicated that under similar test conditions the spray from the chine tires presented less of a potential engine spray ingestion problem than the conventional tires. Neither tire configuration appeared to pose any ingestion problem at aircraft speeds in excess of the hydroplaning speed for each tire, however, significant differences were noted in the spray patterns of the two sets of tires at sub-hydroplaning speeds. At sub-hydroplaning speeds, the conventional tires produced substantial spray above the wing which approached the general area of the engine air inlet at lower test speeds. The chine tires produced two distinct spray plumes at sub-hydroplaning speeds: one low-level plume which presented no apparent threat of ingestion, and one which at most test speeds was observed to be below the wing leading edge and thus displaced from the intakes on the engine nacelle.

Diesel engine experiments with oxygen enrichment, water addition and lower-grade fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sekar, R.R.; Marr, W.W.; Cole, R.L.

1990-01-01

The concept of oxygen enriched air applied to reciprocating engines is getting renewed attention in the context of the progress made in the enrichment methods and the tougher emissions regulations imposed on diesel and gasoline engines. An experimental project was completed in which a direct injection diesel engine was tested with intake oxygen levels of 21% -- 35%. Since an earlier study indicated that it is necessary to use a cheaper fuel to make the concept economically attractive, a less refined fuel was included in the test series. Since a major objection to the use of oxygen enriched combustion airmore » had been the increase in NO{sub x} emissions, a method must be found to reduce NO{sub x}. Introduction of water into the engine combustion process was included in the tests for this purpose. Fuel emulsification with water was the means used here even though other methods could also be used. The teat data indicated a large increase in engine power density, slight improvement in thermal efficiency, significant reductions in smoke and particulate emissions and NO{sub x} emissions controllable with the addition of water. 15 refs., 10 figs., 2 tabs.« less

Effects of industrially produced trans fat on markers of systemic inflammation: evidence from a randomized trial in women

USDA-ARS?s Scientific Manuscript database

Background: Intake of industrial trans fatty acids (TFA) has been positively associated to systemic markers of low-grade inflammation and endothelial dysfunction in cross-sectional studies, but results from intervention studies are inconclusive. Objective: To examine the effect of a high intake of T...

78 FR 64064 - Agency Information Collection (Principles of Excellence Complaint System Intake) Activity Under...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

... (Principles of Excellence Complaint System Intake) Activity Under OMB Review AGENCY: Veterans Benefits... to the Office of Management and Budget (OMB) for review and comment. The PRA submission describes the... Information and Regulatory Affairs, Office of Management and Budget, Attn: VA Desk Officer; 725 17th St. NW...

Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet.

PubMed

Clarys, Peter; Deliens, Tom; Huybrechts, Inge; Deriemaeker, Peter; Vanaelst, Barbara; De Keyzer, Willem; Hebbelinck, Marcel; Mullie, Patrick

2014-03-24

The number of studies comparing nutritional quality of restrictive diets is limited. Data on vegan subjects are especially lacking. It was the aim of the present study to compare the quality and the contributing components of vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diets. Dietary intake was estimated using a cross-sectional online survey with a 52-items food frequency questionnaire (FFQ). Healthy Eating Index 2010 (HEI-2010) and the Mediterranean Diet Score (MDS) were calculated as indicators for diet quality. After analysis of the diet questionnaire and the FFQ, 1475 participants were classified as vegans (n = 104), vegetarians (n = 573), semi-vegetarians (n = 498), pesco-vegetarians (n = 145), and omnivores (n = 155). The most restricted diet, i.e., the vegan diet, had the lowest total energy intake, better fat intake profile, lowest protein and highest dietary fiber intake in contrast to the omnivorous diet. Calcium intake was lowest for the vegans and below national dietary recommendations. The vegan diet received the highest index values and the omnivorous the lowest for HEI-2010 and MDS. Typical aspects of a vegan diet (high fruit and vegetable intake, low sodium intake, and low intake of saturated fat) contributed substantially to the total score, independent of the indexing system used. The score for the more prudent diets (vegetarians, semi-vegetarians and pesco-vegetarians) differed as a function of the used indexing system but they were mostly better in terms of nutrient quality than the omnivores.

Comparison of Nutritional Quality of the Vegan, Vegetarian, Semi-Vegetarian, Pesco-Vegetarian and Omnivorous Diet

PubMed Central

Clarys, Peter; Deliens, Tom; Huybrechts, Inge; Deriemaeker, Peter; Vanaelst, Barbara; De Keyzer, Willem; Hebbelinck, Marcel; Mullie, Patrick

2014-01-01

The number of studies comparing nutritional quality of restrictive diets is limited. Data on vegan subjects are especially lacking. It was the aim of the present study to compare the quality and the contributing components of vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diets. Dietary intake was estimated using a cross-sectional online survey with a 52-items food frequency questionnaire (FFQ). Healthy Eating Index 2010 (HEI-2010) and the Mediterranean Diet Score (MDS) were calculated as indicators for diet quality. After analysis of the diet questionnaire and the FFQ, 1475 participants were classified as vegans (n = 104), vegetarians (n = 573), semi-vegetarians (n = 498), pesco-vegetarians (n = 145), and omnivores (n = 155). The most restricted diet, i.e., the vegan diet, had the lowest total energy intake, better fat intake profile, lowest protein and highest dietary fiber intake in contrast to the omnivorous diet. Calcium intake was lowest for the vegans and below national dietary recommendations. The vegan diet received the highest index values and the omnivorous the lowest for HEI-2010 and MDS. Typical aspects of a vegan diet (high fruit and vegetable intake, low sodium intake, and low intake of saturated fat) contributed substantially to the total score, independent of the indexing system used. The score for the more prudent diets (vegetarians, semi-vegetarians and pesco-vegetarians) differed as a function of the used indexing system but they were mostly better in terms of nutrient quality than the omnivores. PMID:24667136

Food choice in hyperthyroidism: potential influence of the autonomic nervous system and brain serotonin precursor availability.

PubMed

Pijl, H; de Meijer, P H; Langius, J; Coenegracht, C I; van den Berk, A H; Chandie Shaw, P K; Boom, H; Schoemaker, R C; Cohen, A F; Burggraaf, J; Meinders, A E

2001-12-01

We explored energy and macronutrient intake in patients with Graves' hyperthyroidism. We specifically hypothesized that hyperthyroidism is associated with increased appetite for carbohydrates, because of enhanced sympathetic tone and diminished serotonin mediated neurotransmission in the brain. To test this hypothesis, we measured food intake by dietary history and food selected for lunch in the laboratory in 14 patients with Graves' hyperthyroidism. Twenty-four-hour catecholamine excretion was used as a measure of activity of the sympathetic nervous system (SNS) and the plasma [Trp]/[NAA] ratio was measured to estimate (rate limiting) precursor availability for brain 5-hydroxytryptamine synthesis. All measurements were repeated after the subjects had been treated to establish euthyroidism. In addition, the effects of nonselective beta-adrenoceptor blockade upon these parameters were studied to evaluate the influence of beta-adrenergic hyperactivity on food intake. Hyperthyroidism was marked by increased SNS activity and reduced plasma [Trp]/[NAA] ratio. Accordingly, energy intake was considerably and significantly increased in hyper vs. euthyroidism, which was fully attributable to enhanced carbohydrate consumption, as protein and fat intake were not affected. These results suggest that hyperthyroidism alters the neurophysiology of food intake regulation. Increased SNS activity and reduced Trp precursor availability for 5-hydroxytryptamine synthesis in the brain may drive the marked hyperphagia and craving for carbohydrates that appears to characterize hyperthyroid patients. Because propranolol did not affect food intake in hyperthyroidism, the potential effect of catecholamines on food intake might be mediated by alpha-adrenoceptors.

High Salt Intake Attenuates Breast Cancer Metastasis to Lung.

PubMed

Xu, Yijuan; Wang, Wenzhe; Wang, Minmin; Liu, Xuejiao; Lee, Mee-Hyun; Wang, Mingfu; Zhang, Hao; Li, Haitao; Chen, Wei

2018-04-04

Diet-related factors are thought to modify the risk of cancers, while the influence of high salt intake remains largely uncharacterized. Breast cancer is the most common cancer in women worldwide. In the present study, we examined the effect of salt intake on breast cancer by using a 4T1 mouse mammary tumor model. Unexpectedly, both the fitness and the survival rate of the tumor-bearing mice were improved by high salt intake. Similarly, high salt intake suppressed the primary tumor growth as well as metastasis to lung in mice. Mechanistically, high salt intake greatly reduced food intake and thus might exert antitumor effect through mimicking calorie restriction. Immunoblotting showed the lower proliferation marker Ki-67 and the higher expression of the tumor suppressor gene p53 in tumors of high salt intake mice. Importantly, high salt intake might induce hyperosmotic stress, which sensitized breast cancer cells to p53-dependent anoikis. Collectively, our findings raise the possibility that endogenous salt deposition might act as the first-line defense system against breast cancer progression as well as metastasis.

Test Duration for Water Intake, Average Daily Gain, and Dry Matter Intake in Beef Cattle.

PubMed

Ahlberg, C M; Allwardt, K; Broocks, A; Bruno, K; McPhillips, L; Taylor, A; Krehbiel, C R; Calvo-Lorenzo, M; Richards, C J; Place, S E; DeSilva, U; VanOverbeke, D L; Mateescu, R G; Kuehn, L A; Weaber, R L; Bormann, J M; Rolf, M M

2018-05-22

Water is an essential nutrient, but the effect it has on performance generally receives little attention. There are few systems and guidelines for collection of water intake phenotypes in beef cattle, which makes large-scale research on water intake a challenge. The Beef Improvement Federation has established guidelines for feed intake and average daily gain tests, but no guidelines exist for water intake. The goal of this study was to determine the test duration necessary for collection of accurate water intake phenotypes. To facilitate this goal, individual daily water intake (WI) and feed intake (FI) records were collected on 578 crossbred steers for a total of 70 d using an Insentec system at the Oklahoma State University Willard Sparks Beef Research Unit. Steers were fed in 5 groups and were individually weighed every 14 days. Within each group, steers were blocked by body weight (low and high) and randomly assigned to 1 of 4 pens containing approximately 30 steers per pen. Each pen provided 103.0 m2 of shade and included an Insentec system containing 6 feed bunks and 1 water bunk. Steers were fed a constant diet across groups and dry matter intake was calculated using the average of weekly percent dry matter within group. Average feed and water intakes for each animal were computed for increasingly large test durations (7, 14, 21, 28, 35, 42, 49, 56, 63 and 70 d), and ADG was calculated using a regression formed from body weights (BW) taken every14 d (0, 14, 28, 42, 56, and 70 d). Intervals for all traits were computed starting from both the beginning (d 0) and the end of the testing period (d 70). Pearson and Spearman correlations were computed for phenotypes from each shortened test period and for the full 70-d test. Minimum test duration was determined when the Pearson correlations were greater than 0.95 for each trait. Our results indicated that minimum test duration for WI, DMI, and ADG were 35, 42, and 70 d, respectively. No comparable studies exist for WI; however, our results for FI and ADG are consistent with those in the literature. Although further testing in other populations of cattle and areas of the country should take place, our results suggest that WI phenotypes can be collected concurrently with DMI, without extending test duration, even if following procedures for decoupled intake and gain tests.

Endogenous and dietary lipids influencing feed intake and energy metabolism of periparturient dairy cows.

PubMed

Kuhla, B; Metges, C C; Hammon, H M

2016-07-01

The high metabolic priority of the mammary gland for milk production, accompanied by limited feed intake around parturition results in a high propensity to mobilize body fat reserves. Under these conditions, fuel selection of many peripheral organs is switched, for example, from carbohydrate to fat utilization to spare glucose for milk production and to ensure partitioning of tissue- and dietary-derived nutrients toward the mammary gland. For example, muscle tissue uses nonesterified fatty acids (NEFA) but releases lactate and amino acids in a coordinated order, thereby providing precursors for milk synthesis or hepatic gluconeogenesis. Tissue metabolism and in concert, nutrient partitioning are controlled by the endocrine system involving a reduction in insulin secretion and systemic insulin sensitivity and orchestrated changes in plasma hormones such as insulin, adiponectin, insulin growth factor-I, growth hormone, glucagon, leptin, glucocorticoids, and catecholamines. However, the endocrine system is highly sensitive and responsive to an overload of fatty acids no matter if excessive NEFA supply originates from exogenous or endogenous sources. Feeding a diet containing rumen-protected fat from late lactation to calving and beyond exerts similar negative effects on energy intake, glucose and insulin concentrations as does a high extent of body fat mobilization around parturition in regard to the risk for ketosis and fatty liver development. High plasma NEFA concentrations are thought not to act directly at the brain level, but they increase the energy charge of the liver which is, signaled to the brain to diminish feed intake. Cows differing in fat mobilization during the transition phase differ in their hepatic energy charge, whole body fat oxidation, glucose metabolism, plasma ghrelin, and leptin concentrations and in feed intake several week before parturition. Hence, a high lipid load, no matter if stored, mobilized or fed, affects the endocrine system, metabolism, and feed intake, and increases the risk for metabolic disorders. Future research should focus on a timely parallel increase in feed intake and milk yield during early lactation to reduce the impact of body fat on feed intake, metabolic health, and negative energy balance. Copyright © 2015 Elsevier Inc. All rights reserved.

The interaction of central nitrergic and GABAergic systems on food intake in neonatal layer-type chicks.

PubMed

Mokhtarpouriani, Kasra; Zendehdel, Morteza; Jonaidi, Hossein; Babapour, Vahab; Shayan, Parviz

2016-05-01

Most physiological behaviors such as food intake are controlled by the hypothalamus and its nuclei. It has been demonstrated that injection of the paraventricular nucleus of the hypothalamus with nitric oxide (NO) donors elicited changes in the concentration of some amino acids, including GABA. Also, central nitrergic and GABAergic systems are known to provide inputs to the paraventricular nucleus and are involved in food intake control. Therefore, the present study examines the probable interaction of central nitrergic and GABAergic systems on food intake in neonatal layer-type chicks. The results of this study showed that intracerebroventricular (ICV) injection of L-arginine (400 and 800 nmol), as a NO donor, significantly decreased food intake (P < 0.001), but ICV injection of Nω-Nitro-L-arginine methyl ester (L-NAME) (200 and 400 nmol), a NO synthesis inhibitor, increased food intake (P < 0.001). In addition, the orexigenic effect of gaboxadol (0.2 µg), a GABAA agonist, was significantly attenuated in ICV co-injection of L-arginine (200 nmol) and gaboxadol (0.2 µg) (P < 0.001), but it was significantly amplified in ICV co-injection of L-NAME (100 nmol) and gaboxadol (0.2 µg) (P < 0.001). On the other hand, the orexigenic effect of baclofen (0.2 µg), a GABAB agonist, did not change in ICV co-injection of L-arginine (200 nmol) or L-NAME (100 nmol) with baclofen (0.2 µg) (P > 0.05). Also, the hypophagic effect of L-arginine (800 nmol) was significantly amplified in ICV co-injection of picrotoxin (0.5 µg), a GABAA antagonist, or CGP54626 (21 ng), a GABAB antagonist, with L-arginine (800 nmol) (P < 0.001). These results probably suggest an interaction of central nitrergic and GABAergic systems on food intake in neonatal layer-type chicks and GABAA receptors play a major role in this interaction.

A Closer look at calcium absorption and the benefits and risks of dietary versus supplemental calcium.

PubMed

Booth, Anna; Camacho, Pauline

2013-11-01

To perform a thorough search of the literature on calcium research and specifically address the topic of calcium absorption. PubMed and Ovid were the main engines used for primary literature searches; textbooks, review articles, and book chapters are examples of the other sources used for supplemental information. Regarding calcium absorption, it seems apparent that the absorption efficiency of all calcium salts, regardless of solubility, is fairly equivalent and not significantly less than the absorption efficiency of dietary calcium. However, dietary calcium has been shown to have greater impact in bone building than supplemental calcium. This is likely due to improved absorption with meals and the tendency of people to intake smaller amounts more frequently, which is more ideal for the body's method of absorption. In addition, the cardiovascular risks of excessive calcium intake appear to be more closely related to calcium supplements than dietary calcium; this relationship continues to be controversial in the literature. We conclude that further studies are needed for direct comparison of supplemental and dietary calcium to fully establish if one is superior to the other with regard to improving bone density. We also propose further studies on the cardiovascular risk of long-term increased calcium intake and on physician estimates of patients' daily calcium intake to better pinpoint those patients who require calcium supplementation.

Evaluation of certain food additives and contaminants.

PubMed

2004-01-01

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, with a view to recommending acceptable daily intakes (ADIs) and to prepare specifications for the identity and purity of food additives. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of food additives (including flavouring agents) and contaminants, assessments of intake, and the establishment and revision of specifications for food additives. A summary follows of the Committee's evaluations of toxicological and intake data on various specific food additives (alpha-amylase from Bacillus lichenformis containing a genetically engineered alpha-amylase gene from B. licheniformis, annatto extracts, curcumin, diacetyl and fatty acid esters of glycerol, D-tagatose, laccase from Myceliophthora thermophila expressed in Aspergillus oryzae, mixed xylanase, beta-glucanase enzyme preparation produced by a strain of Humicola insolens, neotame, polyvinyl alcohol, quillaia extracts and xylanase from Thermomyces lanuginosus expressed in Fusarium venenatum), flavouring agents, a nutritional source of iron (ferrous glycinate, processed with citric acid), a disinfectant for drinking-water (sodium dichloroisocyanurate) and contaminants (cadmium and methylmercury). Annexed to the report are tables summarizing the Committee's recommendations for ADIs of the food additives, recommendations on the flavouring agents considered, and tolerable intakes of the contaminants considered, changes in the status of specifications and further information requested or desired.

Role of relaxin-3/RXFP3 system in stress-induced binge-like eating in female rats.

PubMed

Calvez, Juliane; de Ávila, Camila; Matte, Louis-Olivier; Guèvremont, Geneviève; Gundlach, Andrew L; Timofeeva, Elena

2016-03-01

Binge eating is frequently stimulated by stress. The neuropeptide relaxin-3 (RLN3) and its native receptor RXFP3 are implicated in stress and appetitive behaviors. We investigated the dynamics of the central RLN3/RXFP3 system in a newly established model of stress-induced binge eating. Female Sprague-Dawley rats were subjected to unpredictable intermittent 1-h access to 10% sucrose. When sucrose intake stabilized, rats were assessed for consistency of higher or lower sucrose intake in response to three unpredictable episodes of foot-shock stress; and assigned as binge-like eating prone (BEP) or binge-like eating resistant (BER). BEP rats displayed elevated consumption of sucrose under non-stressful conditions (30% > BER) and an additional marked increase in sucrose intake (60% > BER) in response to stress. Conversely, sucrose intake in BER rats was unaltered by stress. Chow intake was similar in both phenotypes on 'non-stress' days, but was significantly reduced by stress in BER, but not BEP, rats. After stress, BEP, but not BER, rats displayed a significant increase in RLN3 mRNA levels in the nucleus incertus. In addition, in response to stress, BEP, but not BER, rats had increased RXFP3 mRNA levels in the paraventricular and supraoptic nuclei of the hypothalamus. Intracerebroventricular administration of a selective RXFP3 antagonist, R3(B1-22)R, blocked the stress-induced increase in sucrose intake in BEP rats and had no effect on sucrose intake in BER rats. These results provide important evidence for a role of the central RLN3/RXFP3 system in the regulation of stress-induced binge eating in rats, and have therapeutic implications for eating disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

Whey proteins in the regulation of food intake and satiety.

PubMed

Luhovyy, Bohdan L; Akhavan, Tina; Anderson, G Harvey

2007-12-01

Whey protein has potential as a functional food component to contribute to the regulation of body weight by providing satiety signals that affect both short-term and long-term food intake regulation. Because whey is an inexpensive source of high nutritional quality protein, the utilization of whey as a physiologically functional food ingredient for weight management is of current interest. At present, the role of individual whey proteins and peptides in contributing to food intake regulation has not been fully defined. However, Whey protein reduces short-term food intake relative to placebo, carbohydrate and other proteins. Whey protein affects satiation and satiety by the actions of: (1) whey protein fractions per se; (2) bioactive peptides; (3) amino-acids released after digestion; (4) combined action of whey protein and/or peptides and/or amino acids with other milk constituents. Whey ingestion activates many components of the food intake regulatory system. Whey protein is insulinotropic, and whey-born peptides affect the renin-angiotensin system. Therefore whey protein has potential as physiologically functional food component for persons with obesity and its co-morbidities (hypertension, type II diabetes, hyper- and dislipidemia). It remains unclear, however, if the favourable effects of whey on food intake, subjective satiety and intake regulatory mechanisms in humans are obtained from usual serving sizes of dairy products. The effects described have been observed in short-term experiments and when whey is consumed in much higher amounts.

IET. Aerial view of snaptran destructive experiment in 1964. Camera ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET. Aerial view of snaptran destructive experiment in 1964. Camera facing north. Test cell building (TAN-624) is positioned away from coupling station. Weather tower in right foreground. Divided duct just beyond coupling station. Air intake structure on south side of shielded control room. Experiment is on dolly at coupling station. Date: 1964. INEEL negative no. 64-1736 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Population Health in Regions Adjacent to the Semipalatinsk Nuclear Test Site

DTIC Science & Technology

1998-09-01

HEALTH OCEANS, AND FISHERIES EFFECTS OF RADIATION ATTN: DIRECTOR U.S. FOOD AND DRUG ADMINISTRATION ATTN: WINCHESTER ENGINEERING AND OAK RIDGE ASSOCIATED...radionuclides [7]. This commission assessed population health strontium-90 and cesium-137 through the human and hygienic, environmental, and radiation food ...as intake of radioactive sub- identified strontium-90 and potassium-40 in the stances with food and water are provided below. 19 Population Health in