Science.gov

Sample records for air conditioned room

  1. Control of Computer Room Air Conditioning using IT Equipment Sensors

    SciTech Connect

    Bell, Geoffrey C.; Storey, Bill; Patterson, Michael K.

    2009-09-30

    The goal of this demonstration was to show how sensors in IT equipment could be accessed and used to directly control computer room air conditioning. The data provided from the sensors is available on the IT network and the challenge for this project was to connect this information to the computer room air handler's control system. A control strategy was developed to enable separate control of the chilled water flow and the fans in the computer room air handlers. By using these existing sensors in the IT equipment, an additional control system is eliminated (or could be redundant) and optimal cooling can be provided saving significant energy. Using onboard server temperature sensors will yield significant energy reductions in data centers. Intel hosted the demonstration in its Santa Clara, CA data center. Intel collaborated with IBM, HP, Emerson, Wunderlich-Malec Engineers, FieldServer Technologies, and LBNL to install the necessary components and develop the new control scheme. LBNL also validated the results of the demonstration.

  2. [Design, equipment, and management for air conditioning in operating room].

    PubMed

    Fuji, Kumiko; Mizuno, Ju

    2011-11-01

    In order to maintain air cleanliness in the operating room (OR) permanently, air exchange rate in the OR should be more than 15 times x hr(-1), the laminar air flow should be kept, and the numbers of the persons in the OR and the numbers of opening and closing OR door should be limited. High efficiency particulate air (HEPA) filter is effective in collection and removal of airborne microbes, and is used in the biological clean room. We need to design, equip, and manage the OR environment according to Guideline for Design and Operation of Hospital HVAC Systems HEAS-02-2004 established by Healthcare Engineering Association of Japan and Guideline for Prevention of Surgical Site Infection (SSI) established by the Center for Disease Control and Prevention (CDC) in the USA. PMID:22175178

  3. The Design of Research Laboratories. Part I: A General Assessment. Part II: Air Conditioning and Conditioned Rooms.

    ERIC Educational Resources Information Center

    Legget, R. F.; Hutcheon, N. B.

    Design factors in the planning of research laboratories are described which include--(1) location, (2) future expansion, (3) internal flexibility, (4) provision of services, (5) laboratory furnishing, (6) internal traffic, (7) space requirements, and (8) building costs. A second part discusses air-conditioning and conditioned rooms--(1)…

  4. Impact of surface disinfection and sterile draping of furniture on room air quality in a cardiac procedure room with a ventilation and air-conditioning system (extrusion airflow, cleanroom class 1b (DIN 1946-4))

    PubMed Central

    Below, Harald; Ryll, Sylvia; Empen, Klaus; Dornquast, Tina; Felix, Stefan; Rosenau, Heike; Kramer, Sebastian; Kramer, Axel

    2010-01-01

    In a cardiac procedure room, ventilated by a ventilation and air-conditioning system with turbulent mixed airflow, a protection zone in the operating area could be defined through visualization of airflows. Within this protection zone, no turbulence was detectable in the room air. Under the given conditions, disinfection of all surfaces including all furniture and equipment after the last operation and subsequent draping of furniture and all equipment that could not be removed from the room with sterile surgical drapes improved the indoor room air quality from cleanroom class C to cleanroom class B. This also allows procedures with elevated requirements to be performed in room class 1b. PMID:20941336

  5. Basement utility room (room 24; air handling room), near the ...

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

    Basement utility room (room 24; air handling room), near the west end of the combat operations center, looking southwest towards fan system one, air ducts, and walk-in filter rooms. The exterior equipment well is visible at the left - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  6. Benefits of Leapfrogging to Superefficiency and Low Global Warming Potential Refrigerants in Room Air Conditioning

    SciTech Connect

    Shah, Nihar K.; Wei, Max; Letschert, Virginie; Phadke, Amol A.

    2015-10-01

    Hydrofluorocarbons (HFCs) emitted from uses such as refrigerants and thermal insulating foam, are now the fastest growing greenhouse gases (GHGs), with global warming potentials (GWP) thousands of times higher than carbon dioxide (CO2). Because of the short lifetime of these molecules in the atmosphere,1 mitigating the amount of these short-lived climate pollutants (SLCPs) provides a faster path to climate change mitigation than control of CO2 alone. This has led to proposals from Africa, Europe, India, Island States, and North America to amend the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) to phase-down high-GWP HFCs. Simultaneously, energy efficiency market transformation programs such as standards, labeling and incentive programs are endeavoring to improve the energy efficiency for refrigeration and air conditioning equipment to provide life cycle cost, energy, GHG, and peak load savings. In this paper we provide an estimate of the magnitude of such GHG and peak electric load savings potential, for room air conditioning, if the refrigerant transition and energy efficiency improvement policies are implemented either separately or in parallel.

  7. Hepa room air purifier

    SciTech Connect

    Davis, G.B.

    1986-12-16

    This patent describes a portable air purification apparatus comprising a housing including a base portion and cover means, the base portion including an air deflection means and a plate means mounted in spaced relationship to the air deflection means so as to create a substantially continuous air exhaust opening therebetween. A centrifugal fan means is disposed between the plate means and the air deflection means and is mounted so as to direct air radially outwardly therefrom through the air exhaust opening, at least one opening through the plate means to permit air flow therethrough to the centrifugal fan means. The motor means carried by the base portion and extends upwardly with respect to the opening in the plate means, the motor means having drive shaft means for driving the centrifugal fan means. An air filter means is mounted between the base portion and the cover means so that air is drawn therethrough toward the centrifugal fan means, and a means for secures the cover means relative to the base means to thereby retain the air filter means therebetween.

  8. Field Test of Room-to-Room Uniformity of Ventilation Air Distribution in Two New Houses

    SciTech Connect

    Hendron, Robert; Anderson, Ren; Barley, Dennis; Rudd, Armin; Townsend, Aaron; Hancock, Ed

    2006-12-01

    This report describes a field test to characterize the uniformity of room-to-room ventilation air distribution under various operating conditions by examining multi-zone tracer gas decay curves and calculating local age-of-air.

  9. High Efficiency Room Air Conditioner

    SciTech Connect

    Bansal, Pradeep

    2015-01-01

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  10. ZnO/MoO 3 mixed oxide nanotube: A highly efficient and stable catalyst for degradation of dye by air under room conditions

    NASA Astrophysics Data System (ADS)

    Huang, Jiguo; Wang, Xiaohong; Li, Sen; Wang, Yu

    2010-10-01

    As a continuation of our work to develop catalysts with high activity for catalytic air wet oxidation process under mild conditions, degradation of wastewater containing 0.3 g/L Safranin-T (ST) by air oxidation over ZnO/MoO 3 nanotube catalyst was studied. It was found the decolorization efficiency and the chemical oxygen demand (COD) removal of ST reached above 98% and 95%, respectively, within 18 min at room temperature and atmospheric pressure. And the organic pollutants were totally mineralized to simple inorganic species such as HCO 3-, Cl - and NO 3-, while the total organic carbon (TOC) decreased 99.3%. The structure and morphology of the catalyst after ten cycling runs showed that the catalyst was stable under such operating condition and the leaching test showed negligible leaching effect. This ZnO/MoO 3 nanotube is proved to be an active and stable heterogeneous catalyst in CWAO of ST under extremely mild conditions.

  11. Historical and projected emissions of HCFC-22 and HFC-410A from China's room air conditioning sector

    NASA Astrophysics Data System (ADS)

    Wang, Ziyuan; Fang, Xuekun; Li, Li; Bie, Pengju; Li, Zhifang; Hu, Jianxin; Zhang, Boya; Zhang, Jianbo

    2016-05-01

    Recent decades witnessed the increase in production and uses of HCFC-22 (chlorodifluoromethane, CHClF2) and its alternative, HFC-410A (a blend of difluoromethane and pentafluoroethane), in China in response to the booming of room air conditioners (RACs) for both domestic use and exports. HCFC-22 is an ozone-depleting substance under the Montreal Protocol, while both HCFC-22 and HFC-410A are greenhouse gases (GHGs). This study provides a most comprehensive consumption and emission inventory of refrigerants emissions (HCFC-22 and HFC-410A) from RAC sector during 1995-2014, for the first time. Our estimates show that HCFC-22 emissions increased from 0.7 Gg/yr in 1995 to 48.2 Gg/yr in 2014. The accumulative emissions contributed to global total HCFCs emissions by 4.4% (3.3%-6.1%) CFC-11-equivalent (CFC-11-eq) and 5.4% (4.1%-7.5%) CO2-equivalent (CO2-eq) during 1995-2012. If left uncontrolled, accumulative emissions of HFC-410A will be12.4 (7.1-20.2) CO2-eq Pg during 2015-2050, which can offset the global climate benefits achieved by the Montreal Protocol. The HFC-410A emissions from China's RAC sector are estimated to be of importance to both global HFCs emissions and China's GHG emissions. Further, we probed the emission mitigation performances of the current 2014 North American Proposal scenario and a modified more ambitious scenario. The emissions of two mitigation scenarios are only 28% and 22% of the emissions without mitigation actions, respectively. This study is the first effort to map the transition of eliminated substance HCFC-22 and its alternative HFC-410A in RAC sector. Therefore, alternative chemicals should be scrutinized with cautions before they are promoted and applied.

  12. Historical and projected emissions of HCFC-22 and HFC-410A from China's room air conditioning sector

    NASA Astrophysics Data System (ADS)

    Wang, Ziyuan; Fang, Xuekun; Li, Li; Bie, Pengju; Li, Zhifang; Hu, Jianxin; Zhang, Boya; Zhang, Jianbo

    2016-05-01

    Recent decades witnessed the increase in production and uses of HCFC-22 (chlorodifluoromethane, CHClF2) and its alternative, HFC-410A (a blend of difluoromethane and pentafluoroethane), in China in response to the booming of room air conditioners (RACs) for both domestic use and exports. HCFC-22 is an ozone-depleting substance under the Montreal Protocol, while both HCFC-22 and HFC-410A are greenhouse gases (GHGs). This study provides a most comprehensive consumption and emission inventory of refrigerants emissions (HCFC-22 and HFC-410A) from RAC sector during 1995-2014, for the first time. Our estimates show that HCFC-22 emissions increased from 0.7 Gg/yr in 1995 to 48.2 Gg/yr in 2014. The accumulative emissions contributed to global total HCFCs emissions by 4.4% (3.3%-6.1%) CFC-11-equivalent (CFC-11-eq) and 5.4% (4.1%-7.5%) CO2-equivalent (CO2-eq) during 1995-2012. If left uncontrolled, accumulative emissions of HFC-410A will be12.4 (7.1-20.2) CO2-eq Pg during 2015-2050, which can offset the global climate benefits achieved by the Montreal Protocol. The HFC-410A emissions from China's RAC sector are estimated to be of importance to both global HFCs emissions and China's GHG emissions. Further, we probed the emission mitigation performances of the current 2014 North American Proposal scenario and a modified more ambitious scenario. The emissions of two mitigation scenarios are only 28% and 22% of the emissions without mitigation actions, respectively. This study is the first effort to map the transition of eliminated substance HCFC-22 and its alternative HFC-410A in RAC sector. Therefore, alternative chemicals should be scrutinized with cautions before they are promoted and applied.

  13. REACH. Air Conditioning Units.

    ERIC Educational Resources Information Center

    Garrison, Joe; And Others

    As a part of the REACH (Refrigeration, Electro-Mechanical, Air-Conditioning, Heating) electromechanical cluster, this student manual contains individualized instructional units in the area of air conditioning. The instructional units focus on air conditioning fundamentals, window air conditioning, system and installation, troubleshooting and…

  14. Room air monitor for radioactive aerosols

    DOEpatents

    Balmer, David K.; Tyree, William H.

    1989-04-11

    A housing assembly for use with a room air monitor for simultaneous collection and counting of suspended particles includes a casing containing a combination detector-preamplifier system at one end, a filter system at the other end, and an air flow system consisting of an air inlet formed in the casing between the detector-preamplifier system and the filter system and an air passageway extending from the air inlet through the casing and out the end opposite the detector-preamplifier combination. The filter system collects suspended particles transported directly through the housing by means of the air flow system, and these particles are detected and examined for radioactivity by the detector-pre The U.S. Government has rights in this invention pursuant to Contract No. DE-AC04-76DP03533 between the Department of Energy and Rockwell International Corporation.

  15. Room air monitor for radioactive aerosols

    DOEpatents

    Balmer, D.K.; Tyree, W.H.

    1987-03-23

    A housing assembly for use with a room air monitor for simultaneous collection and counting of suspended particles includes a casing containing a combination detector-preamplifier system at one end, a filter system at the other end, and an air flow system consisting of an air inlet formed in the casing between the detector-preamplifier system and the filter system and an air passageway extending from the air inlet through the casing and out the end opposite the detector-preamplifier combination. The filter system collects suspended particles transported directly through the housing by means of the air flow system, and these particles are detected and examined for radioactivity by the detector-preamplifier combination. 2 figs.

  16. Predictions of thermal comfort and pollutant distributions for a thermostatically-controlled, air-conditioned, partitioned room: Numerical results and enhanced graphical presentation

    SciTech Connect

    White, M.D.; Eyler, L.L.

    1989-05-01

    An index of local thermal comfort and pollutant distributions have been computed with the TEMPEST computer code, in a transient simulation of an air-conditioned enclosure with an incomplete partition. This complex three-dimensional air conditioning problem included forced ventilation through inlet veins, flow through a partition, remote return air vents, and infiltration source, a pollutant source, and a thermostatically controlled air conditioning system. Five forced ventilation schemes that varied in vent areas and face velocities were simulated. Thermal comfort was modeled as a three-dimensional scalar field dependent on the fluid velocity and temperature fields; where humidity activity levels, and clothing were considered constants. Pollutants transport was incorporated through an additional constituent diffusion equation. Six distinct graphic techniques for the visualization of the three-dimensional data fields of air velocity, temperature, and comfort index were tested. 4 refs., 7 figs., 1 tab.

  17. Air-Conditioning Mechanic.

    ERIC Educational Resources Information Center

    Marine Corps Inst., Washington, DC.

    This student guide, one of a series of correspondence training courses designed to improve the job performance of members of the Marine Corps, deals with the skills needed by air conditioning mechanics. Addressed in the four chapters, or lessons, of the manual are the following topics: principles of air conditioning, refrigeration components as…

  18. No-reheat air-conditioning

    NASA Technical Reports Server (NTRS)

    Obler, H. D.

    1980-01-01

    Air conditioning system, for environmentally controlled areas containing sensitive equipment, regulates temperature and humidity without wasteful and costly reheating. System blends outside air with return air as dictated by various sensors to ensure required humidity in cooled spaces (such as computer room).

  19. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Room air conditioners. 429.15 Section 429.15 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.15 Room air conditioners. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to room air...

  20. Tritium Room Air Monitor Operating Experience Review

    SciTech Connect

    L. C. Cadwallader; B. J. Denny

    2008-09-01

    Monitoring the breathing air in tritium facility rooms for airborne tritium is a radiological safety requirement and a best practice for personnel safety. Besides audible alarms for room evacuation, these monitors often send signals for process shutdown, ventilation isolation, and cleanup system actuation to mitigate releases and prevent tritium spread to the environment. Therefore, these monitors are important not only to personnel safety but also to public safety and environmental protection. This paper presents an operating experience review of tritium monitor performance on demand during small (1 mCi to 1 Ci) operational releases, and intentional airborne inroom tritium release tests. The tritium tests provide monitor operation data to allow calculation of a statistical estimate for the reliability of monitors annunciating in actual tritium gas airborne release situations. The data show a failure to operate rate of 3.5E-06/monitor-hr with an upper bound of 4.7E-06, a failure to alarm on demand rate of 1.4E-02/demand with an upper bound of 4.4E-02, and a spurious alarm rate of 0.1 to 0.2/monitor-yr.

  1. Stability limit of room air temperature of a VAV system

    SciTech Connect

    Matsuba, Tadahiko; Kamimura, Kazuyuki; Kasahara, Masato; Kimbara, Akiomi; Kurosu, Shigeru; Murasawa, Itaru; Hashimoto, Yukihiko

    1998-12-31

    To control heating, ventilating, and air-conditioning (HVAC) systems, it has been necessary to accept an analog system controlled mainly by proportional-plus-integral-plus-derivative (PID) action. However, when conventional PID controllers are replaced with new digital controllers by selecting the same PID parameters as before, the control loops have often got into hunting phenomena, which result in undamped oscillations. Unstable control characteristics (such as huntings) are thought to be one of the crucial problems faced by field operators. The PID parameters must be carefully selected to avoid instabilities. In this study, a room space is simulated as a thermal system that is air-conditioned by a variable-air-volume (VAV) control system. A dynamic room model without infiltration or exfiltration, which is directly connected to a simple air-handling unit without an economizer, is developed. To explore the possible existence of huntings, a numerical system model is formulated as a bilinear system with time-delayed feedback, and a parametric analysis of the stability limit is presented. Results are given showing the stability region affected by the selection of control and system parameters. This analysis was conducted to help us tune the PID controllers for optimal HVAC control.

  2. 46. Communication equipment room, shock isolator air compressor at right, ...

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

    46. Communication equipment room, shock isolator air compressor at right, looking northeast - Ellsworth Air Force Base, Delta Flight, Launch Control Facility, County Road CS23A, North of Exit 127, Interior, Jackson County, SD

  3. INTERIOR OF COMMUNICATIONS ROOM. VIEW TO NORTHEAST Plattsburgh Air ...

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

    INTERIOR OF COMMUNICATIONS ROOM. VIEW TO NORTHEAST - Plattsburgh Air Force Base, Air Force Communications Systems (AFCS) Maintenance Facility, Off Alabama Avenue, adjacent to Flightline Apron, Plattsburgh, Clinton County, NY

  4. 45. Communication equipment room, cable air dryer on left, motorola ...

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

    45. Communication equipment room, cable air dryer on left, motorola base station (vhf) at right, looking southwest - Ellsworth Air Force Base, Delta Flight, Launch Control Facility, County Road CS23A, North of Exit 127, Interior, Jackson County, SD

  5. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Room air conditioners. 429.15 Section 429.15 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.15 Room air conditioners. (a) Sampling plan for selection of units for testing. (1)...

  6. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in...

  7. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in...

  8. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in...

  9. High efficiency air cycle air conditioning system

    SciTech Connect

    Rannenberg, G. C.

    1985-11-19

    An air cycle air conditioning system is provided with regenerative heat exchangers upstream and downstream of an expansion turbine. A closedloop liquid circulatory system serially connects the two regenerative heat exchangers for regeneration without the bulk associated with air-to-air heat exchange. The liquid circulatory system may also provide heat transport to a remote sink heat exchanger and from a remote load as well as heat exchange within the sink heat exchanger and load for enhanced compactness and efficiency.

  10. Acoustic method for measuring air temperature and humidity in rooms

    NASA Astrophysics Data System (ADS)

    Kanev, N. G.

    2014-05-01

    A method is proposed to determine air temperature and humidity in rooms with a system of sound sources and receivers, making it possible to find the sound velocity and reverberation time. Nomograms for determining the air temperature and relative air humidity are constructed from the found sound velocity and time reverberation values. The required accuracy of measuring these parameters is estimated.

  11. VIEW OF ROOM 136, FACING SOUTHWEST Cape Canaveral Air ...

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

    VIEW OF ROOM 136, FACING SOUTHWEST - Cape Canaveral Air Force Station, Launch Complex 34, Operations Support Building, Freedom Road, Southwest of Launch Stand CX-34, Cape Canaveral, Brevard County, FL

  12. 21. Interior view of citric acid air pollution control room ...

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

    21. Interior view of citric acid air pollution control room (also known as scrubber room) in Components Test Laboratory (T-27), looking southeast. Photograph shows upgraded instrumentation, piping, tanks, and technological modifications installed in 1997-99 to accommodate component testing requirements for the Atlas V missile. - Air Force Plant PJKS, Systems Integration Laboratory, Components Test Laboratory, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

  13. Energy-Efficient Air Conditioning

    SciTech Connect

    Krigger, J.; Stewart, K.

    1999-06-30

    Many people buy or use air conditioners without understanding their designs, components, and operating principles. Proper sizing, selection, installation, maintenance, and correct use are keys to cost-effective operation and lower overall costs. This publication discusses both central and room air conditioners. Heat pumps, which provide both home cooling and heating, are not covered in this publication. Contact www.eren.doe.gov/consumerinfo for more information.

  14. Air Conditioning Does Reduce Air Pollution Indoors

    ERIC Educational Resources Information Center

    Healy, Bud

    1970-01-01

    Report of the winter meeting of the American Society of Heating, Refrigerating and Air-Conditioning Engineers. Subjects covered are--(1) title subject, (2) predictions for the human habitat in 1994, (3) fans, and (4) fire safety in buildings. (JW)

  15. Laser sheet light flow visualization for evaluating room air flowsfrom Registers

    SciTech Connect

    Walker, Iain S.; Claret, Valerie; Smith, Brian

    2006-04-01

    Forced air heating and cooling systems and whole house ventilation systems deliver air to individual rooms in a house via supply registers located on walls ceilings or floors; and occasionally less straightforward locations like toe-kicks below cabinets. Ideally, the air velocity out of the registers combined with the turbulence of the flow, vectoring of air by register vanes and geometry of register placement combine to mix the supply air within the room. A particular issue that has been raised recently is the performance of multiple capacity and air flow HVAC systems. These systems vary the air flow rate through the distribution system depending on the system load, or if operating in a ventilation rather than a space conditioning mode. These systems have been developed to maximize equipment efficiency, however, the high efficiency ratings do not include any room mixing effects. At lower air flow rates, there is the possibility that room air will be poorly mixed, leading to thermal stratification and reduced comfort for occupants. This can lead to increased energy use as the occupants adjust the thermostat settings to compensate and parts of the conditioned space have higher envelope temperature differences than for the well mixed case. In addition, lack of comfort can be a barrier to market acceptance of these higher efficiency systems To investigate the effect on room mixing of reduced air flow rates requires the measurement of mixing of supply air with room air throughout the space to be conditioned. This is a particularly difficult exercise if we want to determine the transient performance of the space conditioning system. Full scale experiments can be done in special test chambers, but the spatial resolution required to fully examine the mixing problem is usually limited by the sheer number of thermal sensors required. Current full-scale laboratory testing is therefore severely limited in its resolution. As an alternative, we used a water-filled scale model

  16. Air conditioned suit

    NASA Technical Reports Server (NTRS)

    Carl, G. R. (Inventor)

    1973-01-01

    An environmentally controlled suit is described consisting of an airtight outergarment attached by an airtight bellows to the wall of a sterile chamber, an undergarment providing for circulation of air near the skin of the wearer, and a circulation system comprised of air supply and distribution to the extremities of the undegarment and central collection and exhaust of air from the midsection of the undergarment. A workman wearing the undergarment and attached circulation system enters the outer garment through a tunnel in the chamber wall and the attached bellows to work in the chamber without any danger of spreading bacteria.

  17. Control Technologies for Room Air-conditioner and Packaged Air-conditioner

    NASA Astrophysics Data System (ADS)

    Ito, Nobuhisa

    Trends of control technologies about air-conditioning machineries, especially room or packaged air conditioners, are presented in this paper. Multiple air conditioning systems for office buildings are mainly described as one application of the refrigeration cycle control technologies including sensors for thermal comfort and heating/ cooling loads are also described as one of the system control technologies. Inverter systems and related technologies for driving variable speed compressors are described in both case of including induction motors and brushless DC motors. Technologies for more accurate control to meet various kind of regulations such as ozone layer destruction, energy saving and global warming, and for eliminating harmonic distortion of power source current, as a typical EMC problem, will be urgently desired.

  18. 44. Communication equipment room, cable air dryer on left, motorola ...

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

    44. Communication equipment room, cable air dryer on left, motorola base station (vhf) in center, telephone repeater group at right, looking west - Ellsworth Air Force Base, Delta Flight, Launch Control Facility, County Road CS23A, North of Exit 127, Interior, Jackson County, SD

  19. Air conditioning system

    DOEpatents

    Lowenstein, Andrew; Miller, Jeffrey; Gruendeman, Peter; DaSilva, Michael

    2005-02-01

    An air conditioner comprises a plurality of plates arranged in a successively stacked configuration with portions thereof having a spaced apart arrangement, and defining between successive adjacent pairs of plates at the spaced apart portions a first and second series of discrete alternating passages wherein a first air stream is passed through the first series of passages and a second air stream is passed through the second series of passages; and said stacked configuration of plates forming integrally therewith a liquid delivery means for delivering from a source a sufficient quantity of a liquid to the inside surfaces of the first series of fluid passages in a manner which provides a continuous flow of the liquid from a first end to a second end of the plurality of plates while in contact with the first air stream.

  20. 23. Station Compressor Room 1 with Air Compressors and Accumulator ...

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

    23. Station Compressor Room 1 with Air Compressors and Accumulator Tanks, view to the south. One of the two large station air compressor units used for depressing the draft tube water level is visible atop a concrete pedestal on the left side of photograph (the second identical compressor is located in an adjacent room). Two of the six station air accumulator tanks are visible in the background. The smaller station service air compressor is visible in right foreground of the photograph was installed in the early 1980s, and replaced the original station service air compressor. - Washington Water Power Clark Fork River Noxon Rapids Hydroelectric Development, Powerhouse, South bank of Clark Fork River at Noxon Rapids, Noxon, Sanders County, MT

  1. Air Conditioning Overflow Sensor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Technology Transfer Office at Stennis Space Center helped a local inventor develop a prototype of an attachment for central air conditioners and heat pumps that helps monitor water levels to prevent condensation overflow. The sensor will indicate a need for drain line maintenance and prevent possible damage caused by drain pan water spillover. An engineer in the Stennis Space Center prototype Development Laboratory used SSC sensor technology in the development of the sensor.

  2. Air conditioning and refrigeration engineering

    SciTech Connect

    Kreith, F.

    1999-12-01

    This book supplies the basics of design, from selecting the optimum system and equipment to preparing the drawings and specifications. It discusses the four phases of preparing a project: gathering information, developing alternatives, evaluating alternatives, and selling the best solution. In addition, the author breaks down the responsibilities of the engineer design documents, computer aided design, and government codes and standards. It provides you with an easy reference to all aspects of the topic. This resource addresses the most current areas of interest, such as computer aided design and drafting, desiccant air conditioning and energy conservation. It is a thorough and convenient guide to air conditioning and refrigeration engineering. Contents include: introduction; psychrometrics; air-conditioning processes and cycles; refrigerants and refrigeration cycles; outdoor design conditions and indoor design criteria; load calculations; air handling units and packaged units; refrigeration components and evaporative coolers; water systems; heating systems; refrigeration systems; thermal storage system; air system basics; absorption systems; air-conditioning systems and selection; and desiccant dehumidification and air-conditioning.

  3. [A trouble in air conditioning in the operating area].

    PubMed

    Katsumata, Kiyoshi; Kaneko, Takehiko; Owaki, Akira

    2004-07-01

    We experienced malfunction of air conditioning system in the operating area. Rust inside the circulating pipe to the operating area was an obstacle to inflow of cold and hot water. Installing an additional air conditioning system and treatment with chemicals to remove the dust made it possible to adjust room temperature appropriately. Anesthesiologists should be interested and understand equipments used in the operation area such as air conditioning system. PMID:15298259

  4. Thermal conditions and perceived air quality in an air-conditioned auditorium

    NASA Astrophysics Data System (ADS)

    Polednik, Bernard; Guz, Łukasz; Skwarczyński, Mariusz; Dudzińska, Marzenna R.

    2016-07-01

    The study reports measurements of indoor air temperature (T) and relative humidity (RH), perceived air quality (PAQ) and CO2, fine aerosol particle number (PN) and mass (PM1) concentrations in an air conditioned auditorium. The measurements of these air physical parameters have been carried out in the unoccupied auditorium with the air conditioning system switched off (AC off mode) and in the unoccupied and occupied auditorium with the air conditioning system switched off during the night and switched on during the day (AC on/off mode). The average indoor air thermal parameters, CO2 concentration and the PAQ value (in decipols) were elevated, while average PM1 concentration was lower in the AC on/off mode. A statistically significant (p < 0.001) positive correlation has been observed between T and PAQ values and CO2 concentrations (r = 0.66 and r = 0.59, respectively) in that AC mode. A significant negative correlation has been observed between T and PN and PM1 concentrations (r = -0.38 and r = -0.49, respectively). In the AC off mode the above relations between T and the particle concentrations were not that unequivocal. These findings may be of importance as they indicate that in certain AC operation modes the indoor air quality deteriorates along with the variation of the indoor air microclimate and room occupation. This, in turn, may adversely affect the comfort and productivity of the users of air conditioned premises.

  5. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Room air conditioners. 429.15 Section 429.15 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND... selected and tested to ensure that— (i) Any represented value of estimated annual operating cost,...

  6. 36. FIFTH FLOOR BLDG. 27, "CLEAN ROOM" AIR FILTERS LOOKING ...

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

    36. FIFTH FLOOR BLDG. 27, "CLEAN ROOM" AIR FILTERS LOOKING SOUTH. - Fafnir Bearing Plant, Bounded on North side by Myrtle Street, on South side by Orange Street, on East side by Booth Street & on West side by Grove Street, New Britain, Hartford County, CT

  7. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 1 2011-01-01 2011-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE CONCERNING DISCLOSURES REGARDING ENERGY CONSUMPTION AND WATER USE OF CERTAIN HOME APPLIANCES AND...

  8. Can airborne fungal allergens pass through an air-conditioning system. [Aspergillus fumigatus

    SciTech Connect

    Elixmann, J.H. ); Linskens, H.F.; Schata, M.; Jorde, W. )

    1989-01-01

    Fungal spores, an important fraction of aeroplankton particles, can be filtered in an air-conditioning system, resulting in a drastic reduction of the spore count in the air-conditioned rooms. Nevertheless, using the EISA inhibition test against Aspergillus fumigatus, it was found that air samples from air-conditioned rooms show inhibition of the serum activity of a highly sensitized patient. There is evidence that airborne allergens can pass both coarse and fine filters of an air-conditioning system.

  9. Control room envelope unfiltered air inleakage test protocols

    SciTech Connect

    Lagus, P.L.; Grot, R.A.

    1997-08-01

    In 1983, the Advisory Committee on Reactor Safeguards (ACRS) recommended that the US NRC develop a control room HVAC performance testing protocol. To date no such protocol has been forthcoming. Beginning in mid-1994, an effort was funded by NRC under a Small Business Innovation Research (SBIR) grant to develop several simplified test protocols based on the principles of tracer gas testing in order to measure the total unfiltered inleakage entering a CRE during emergency mode operation of the control room ventilation system. These would allow accurate assessment of unfiltered air inleakage as required in SRP 6.4. The continuing lack of a standard protocol is unfortunate since one of the significant parameters required to calculate operator dose is the amount of unfiltered air inleakage into the control room. Often it is assumed that, if the Control Room Envelope (CRE) is maintained at +1/8 in. w.g. differential pressure relative to the surroundings, no significant unfiltered inleakage can occur it is further assumed that inleakage due to door openings is the only source of unfiltered air. 23 refs., 13 figs., 2 tabs.

  10. Impact of room fragrance products on indoor air quality

    NASA Astrophysics Data System (ADS)

    Uhde, Erik; Schulz, Nicole

    2015-04-01

    Everyday life can no longer be imagined without fragrances and scented products. For the consumer, countless products exists which are solely or partly intended to give off a certain scent in sufficient concentrations to odorize a complete room. Sprays, diffusers and evaporators, scented candles and automatic devices for the distribution of fragrance liquids are typical examples of such products. If the consumer uses such products, his consent to the release of certain chemicals in his home can be implied, however, he may not know what kind of fragrance substances and solvents will be present in which concentrations. In this study, we determined the volatile emissions of a number of fragrance products in detail. Measurements were carried out under controlled conditions in test chambers. The products were tested in a passive (unused) and an active state, wherever applicable. Following a defined test protocol, the release of volatile organic compounds, ultrafine particles and NOx was monitored for each product. The potential for forming secondary organic aerosols under the influence of ozone was studied, and for a selection of products the long-term emission behavior was assessed. A remarkable variety of fragrance substances was found and more than 100 relevant compounds were identified and quantified. While it is the intended function of such products to release fragrance substances, also considerable amounts of non-odorous solvents and by-products were found to be released from several air fresheners. Emissions rates exceeding 2 mg/(unit*h) were measured for the five most common solvents.

  11. 27. ROOM 210, VIEW TOWARDS THE NORTHWEST. ALL CONDITIONS ARE ...

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

    27. ROOM 210, VIEW TOWARDS THE NORTHWEST. ALL CONDITIONS ARE THE SAME AS DESCRIPTION FOR #24, ABOVE. - Presidio of San Francisco, Cavalry Stables, Cowles Street, between Lincoln Boulevard & McDowell Street, San Francisco, San Francisco County, CA

  12. Smart Sensors Enable Smart Air Conditioning Control

    PubMed Central

    Cheng, Chin-Chi; Lee, Dasheng

    2014-01-01

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection. PMID:24961213

  13. Smart sensors enable smart air conditioning control.

    PubMed

    Cheng, Chin-Chi; Lee, Dasheng

    2014-01-01

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection. PMID:24961213

  14. Computer Developments in Air Conditioning.

    ERIC Educational Resources Information Center

    Pancoast, Ferendino, Grafton and Skeels, Architects, Miami, FL.

    Proceedings of a conference on the present and future uses of computer techniques in the air conditioning field. The recommendation of this report is, for the most part, negative insofar as it applies to the use of computers for design by the small office. However, there should be an awareness of their usefulness in controlling the environmental…

  15. Passive Room-to-Room Air Transfer, Fresno, California (Fact Sheet)

    SciTech Connect

    Not Available

    2014-02-01

    Field testing was performed in a retrofit unoccupied test house in Fresno, California. Three air-based heating, ventilation, and air conditioning (HVAC) distribution systems - a typical airflow ducted system to the bedrooms, a low airflow ducted system to the bedrooms, and a system with no ductwork to the bedrooms - were evaluated during heating, cooling, and midseason conditions. The relative ability of each of the three systems was assessed with respect to relevant Air Conditioning Contractors of America (ACCA) and ASHRAE standards for house temperature uniformity and stability, respectively. Computational fluid dynamics (CFD) modeling also was performed and refined based on comparison to field test results to determine the air flow rate into the bedrooms of over-door and bottom-of-door air transfer grilles.

  16. Distribution and Room Air Mixing Risks to Retrofitted Homes

    SciTech Connect

    Burdick, A.

    2014-12-01

    ​Energy efficiency upgrades reduce heating and cooling loads on a house. With enough load reduction and if the HVAC system warrants replacement, the HVAC system is often upgraded with a more efficient, lower capacity system that meets the loads of the upgraded house. For a single-story house with ceiling supply air diffusers, ducts are often removed and upgraded. For houses with ducts that are embedded in walls, the cost of demolition precludes the replacement of ducts. The challenge with the use of existing ducts is that the reduced airflow creates a decreased throw at the supply registers, and the supply air and room air do not mix well, leading to potential thermal comfort complaints. This project investigates this retrofit scenario. The issues and solutions discussed here are relevant to all climate zones, with emphasis on climates that require cooling.

  17. Distribution and Room Air Mixing Risks to Retrofitted Homes

    SciTech Connect

    Burdick, A.

    2014-12-01

    Energy efficiency upgrades reduce heating and cooling loads on a house. With enough load reduction and if the HVAC system warrants replacement, the HVAC system is often upgraded with a more efficient, lower capacity system that meets the loads of the upgraded house. For a single-story house with ceiling supply air diffusers, ducts are often removed and upgraded. For houses with ducts that are embedded in walls, the cost of demolition precludes the replacement of ducts. The challenge with the use of existing ducts is that the reduced airflow creates a decreased throw at the supply registers, and the supply air and room air do not mix well, leading to potential thermal comfort complaints. This project investigates this retrofit scenario. The issues and solutions discussed here are relevant to all climate zones, with emphasis on climates that require cooling.

  18. The Performance Evaluation of Room Air Conditioner Using R32

    NASA Astrophysics Data System (ADS)

    Taira, Shigeharu; Yazima, Ryuzaburo; Koyama, Shigeru

    This paper deals with an experimental study on the performance evaluation of a room air conditioner using R32. The test room air conditioner is a product developed for the R410A use. The COP, cooling and heating capacities, charge amount of refrigerant, electric power input, refrigerant thermodynamic states in the air conditioner etc. were measured for both refrigerant R410A and R32, based on JIS-C9612 standard. The experimental results of R32 are evaluated in comparison with the results of R410A, and the following are confirmed :(1) The performance of R32 is higher than R410A. This reason is mainly due to the pressure drop and heat exchange characteristics (in the evaporator and the condenser), (2) The charge amount of R32 is less than that of R410A. From the above results, the further improving the performance and saving the refrigerant amount are expected when refrigerant R410A is replaced with R32. The effects of the performance of components on the COP are also analyzed based on the measured thermodynamic states at both ends of components in the system. Then, it's clarified that the most effective factor is irreversibility of the compressor and the following is the pressure drop in low pressure side including the evaporator and the suction pipe in the system.

  19. Decontamination of room air and adjoining wall surfaces by nebulizing hydrogen peroxide

    PubMed Central

    Koburger, Torsten; Below, Harald; Dornquast, Tina; Kramer, Axel

    2011-01-01

    Aim: In 2010, the ASP GLOSAIRTM 400 was introduced in Germany for nebulizing hydrogen peroxide (H2O2). Since there were no results of practical experience, the new method was to be checked under practical conditions for its effectiveness in decontaminating air in rooms, infested with mold after water damage and, at the same time, under experimentally controlled conditions, test surfaces, contaminated with Aspergillus brasiliensis. Method: After the nebulizer was used in two rooms with a massive mold infestation, the air colony count was determined (MAS-100® Zinsser Analytik) and, at the same time, the mold infestation in samples of wall plaster. As part of this controlled study, test surfaces contaminated with Aspergillus brasiliensis were positioned vertically and horizontally in a test room. The effectiveness of the nebulization (5–6% H2O2 for 2 hours) was tested on these surfaces according to EN 13697. Results: In a massive mold infestation resulting from water damage (worst case), an approximately 9-fold decrease in the mold content and an approximately 13-fold decrease in the number of colony-forming units (sum of the bacteria + fungi) could be detected in the room air immediately after the nebulizing was finished. Even in samples of wall and joint plaster, the molds were reduced, although to a distinctly lesser extent. By indoor nebulization of 5–6% H2O2, A. brasiliensis was reduced >4 log on vertical and horizontal surfaces. Discussion: In rooms with a massive mold infestation, the ASP GLOSAIRTM 400 system is suitable for attaining a clear reduction in the fungal and bacterial room air load, lasting for a week. On vertical and horizontal surfaces, contaminated experimentally with A. brasiliensis, a reduction of >4 lg is achieved. As a load of 104 to 105 fungal spores is unlikely to occur on pre-cleaned surfaces, the GLOSAIRTM 400 can be considered a suitable complementary process for the substantial reduction of fungal contamination. PMID:22242090

  20. CONVENIENT SAMPLING OF AIR BACTERIA IN OPERATING ROOMS.

    PubMed

    WARNER, P; GLASSCO, A; KROEKER, J

    1964-02-22

    A convenient arrangement for sampling air bacteria in operating rooms with a slit sampler (the Fort Detrick sampler) is described. Its purpose is to contribute as far as possible to the convenience of the surgical staff and thereby to the safety of the patient. It has the advantages of recording minute-to-minute changes in bacterial air count; it is unobtrusive and yet can be continually observed by a technician; it is not noisy and avoids the dangers of explosion and static electricity; it is inexpensive, and parts are easily replaced; and finally it provides a means of keeping permanent photographic records of bacterial counts. Results of a preliminary trial of this method appeared to be satisfactory. PMID:14118695

  1. Technical and economic analysis of energy efficiency of Chinese room air conditioners

    SciTech Connect

    Fridley, David G.; Rosenquist, Gregory; Jiang, Lin; Li, Aixian; Xin, Dingguo; Cheng, Jianhong

    2001-02-01

    China has experienced tremendous growth in the production and sales of room air conditioners over the last decade. Although minimum room air conditioner energy efficiency standards have been in effect since 1989, no efforts were made during most of the 1990's to update the standard to be more reflective of current market conditions. In 1999, China's State Bureau of Technical Supervision (SBTS) included in their annual plan the development and revision of the 1989 room air conditioner standard, and experts from SBTS worked together with LBNL to analyze the new standards. Based on the engineering and life cycle-cost analyses performed, the most predominant type of room air conditioner in the Chinese market (split-type with a cooling capacity between 2500 and 4500 W (8500 Btu/h and 15,300Btu/h)) can have its efficiency increased cost-effectively to an energy efficiency ratio (EER) of 2.92 W/W (9.9 Btu/hr/W). If an EER standard of 2.92 W/W became effective in 2001, Chinese consumers would be estimated to save over 3.5 billion Yuan (420 million U.S. dollars) over the period of 2001-2020. Carbon emissions over the same period would be reduced by approximately 12 million metric tonnes.

  2. High Energy Efficiency Air Conditioning

    SciTech Connect

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these

  3. Low GWP Refrigerants Modelling Study for a Room Air Conditioner Having Microchannel Heat Exchangers

    SciTech Connect

    Shen, Bo; Bhandari, Mahabir S

    2016-01-01

    Microchannel heat exchangers (MHX) have found great successes in residential and commercial air conditioning applications, being compact heat exchangers, to reduce refrigerant charge and material cost. This investigation aims to extend the application of MHXs in split, room air conditioners (RAC), per fundamental heat exchanger and system modelling. For this paper, microchannel condenser and evaporator models were developed, using a segment-to-segment modelling approach. The microchannel heat exchanger models were integrated to a system design model. The system model is able to predict the performance indices, such as cooling capacity, efficiency, sensible heat ratio, etc. Using the calibrated system and heat exchanger models, we evaluated numerous low GWP (global warming potential) refrigerants. The predicted system performance indices, e.g. cooling efficiency, compressor discharge temperature, and required compressor displacement volume etc., are compared. Suitable replacements for R22 and R-410A for the room air conditioner application are recommended.

  4. Allergies to molds caused by fungal spores in air conditioning equipment

    SciTech Connect

    Schata, M.; Jorde, W. ); Elixmann, J.H.; Linskens, H.F. )

    1989-01-01

    People suffering from various symptoms while in air-conditioned rooms often show sensitizations to fungi that can be isolated when the fungi are removed from air conditioners. By using specific challenge tests it was shown that fungal spores in air conditioners can evoke allergic symptoms. Hyposensitization was the specific therapy prescribed for such allergic reactions. After hyposensitization therapy, more than 70% of the patients so treated could live and work again in air-conditioned rooms without developing specific symptoms.

  5. Modeling indoor air concentrations near emission sources in imperfectly mixed rooms.

    PubMed

    Furtaw, E J; Pandian, M D; Nelson, D R; Behar, J V

    1996-09-01

    Assessments of exposure to indoor air pollutants usually employ spatially well-mixed models which assume homogeneous concentrations throughout a building or room. However, practical experience and experimental data indicate that concentrations are not uniform in rooms containing point sources of emissions; concentrations tend to be greater in close proximity to the source than they are further from it. This phenomenon could account for the observation that "personal air" monitors frequently yield higher concentrations than nearby microenvironmental monitors (i.e., the so-called "personal cloud" effect). In this project, we systematically studied the concentrations of a tracer gas at various distances from its emission source in a controlled-environment, room-size chamber under a variety of ventilation conditions. Measured concentrations in the proximity of the source deviated significantly above the predictions of a conventional well-mixed single-compartment mass balance model. The deviation was found to be a function of distance from the source and total room air flow rate. At typical air flow rates, the average concentration at arm's length (approximately 0.4 meters) from the source exceeds the theoretical well-mixed concentration by a ratio of about 2:1. However, this ratio is not constant; the monitored concentration appears to vary randomly from near the theoretical value to several times above it. Concentration data were fitted to a two-compartment model with the source located in a small virtual compartment within the room compartment. These two compartments were linked with a stochastic air transfer rate parameter. The resulting model provides a more realistic simulation of exposure concentrations than does the well-mixed model for assessing exposure to emissions from active sources. Parameter values are presented for using the enhanced model in a variety of typical situations. PMID:8925388

  6. Numerical Modelling of Airflow and Temperature Distribution in a Living Room with Different Heat Exchange Conditions

    NASA Astrophysics Data System (ADS)

    Gendelis, S.; Jakovičs, A.

    2010-01-01

    Numerical mathematical modelling of the indoor thermal conditions and of the energy losses for separate rooms is an important part of the analysis of the heat-exchange balance and energy efficiency in buildings. The measurements of heat transfer coefficients for bounding structures, the air-tightness tests and thermographic diagnostics done for a building allow the influence of those factors to be predicted more correctly in developed numerical models. The temperature distribution and airflows in a typical room (along with the heat losses) were calculated for different heater locations and solar radiation (modelled as a heat source) through the window, as well as various pressure differences between the openings in opposite walls. The airflow velocities and indoor temperature, including its gradient, were also analysed as parameters of thermal comfort conditions. The results obtained show that all of the listed factors have an important influence on the formation of thermal comfort conditions and on the heat balance in a room.

  7. Existing Whole-House Solutions Case Study: Passive Room-to-Room Air Transfer, Fresno, California

    SciTech Connect

    D. Stecher and A. Poershke

    2014-02-01

    In this project, IBACOS, a U.S. Department of Energy Building America team, assessed a strategy for providing conditioned air to bedrooms when the bedroom doors are closed and measured potential thermal discomfort that occupants may experience when this strategy is used. Builders can use this information to discuss space conditioning options for low-load houses with their clients to determine acceptable comfort levels for occupants in these cost-optimized, energy-efficient houses.

  8. Room Air Conditioners; Appliance Repair--Advanced: 9027.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This Quinmester course includes installations, electrical and mechanical servicing, reverse cycle air conditioning, malfunctions, troubleshooting and repair, discharge, pump down, and recharging the system. The course may be taught as a two or three Quinmester credit course. In each instance the course consists of six instructional blocks:…

  9. Concentration of dimethylnitrosamine in the air of smoke-filled rooms

    SciTech Connect

    Stehlik, G.; Richter, O.; Altmann, H.

    1982-12-01

    In order to evaluate the contribution of volatile nitrosamines from tobacco smoke to indoor air pollution, N-nitroso-dimethylamine (NDMA) and N-nitroso-diethylamine (NDEA) were measured in indoor air under artificial and natural conditions. In controlled experiments under extreme conditions, we found that tobacco smoke-related NDMA levels above 0.07 ng/liter were associated with a highly irritating atmosphere which was scarcely tolerable to those present. In smoke-filled rooms under natural conditions NDMA levels ranged from 0.02 to 0.05 ng/liter except a minimum value of less than 0.01 ng/liter in a restaurant and a maximum of 0.07 ng/liter in a dancing bar. These NDMA levels are thus below comparable values reported by others. The NDMA/NDEA ratios found in air samples taken from some rooms under conditions of everyday life are quite different from those found in sidestream smoke of cigarettes. Irritation was not reported under natural conditions. From the results it is concluded that NDMA levels, measured under real life conditions, are usually not caused by tobacco smoke alone. Evidence for other sources of volatile nitrosamines is discussed.

  10. Collection and analysis of NASA clean room air samples

    NASA Technical Reports Server (NTRS)

    Sheldon, L. S.; Keever, J.

    1985-01-01

    The environment of the HALOE assembly clean room at NASA Langley Research Center is analyzed to determine the background levels of airborne organic compounds. Sampling is accomplished by pumping the clean room air through absorbing cartridges. For volatile organics, cartridges are thermally desorbed and then analyzed by gas chromatography and mass spectrometry, compounds are identified by searching the EPA/NIH data base using an interactive operator INCOS computer search algorithm. For semivolatile organics, cartridges are solvent entracted and concentrated extracts are analyzed by gas chromatography-electron capture detection, compound identification is made by matching gas chromatogram retention times with known standards. The detection limits for the semivolatile organics are; 0.89 ng cu m for dioctylphlhalate (DOP) and 1.6 ng cu m for polychlorinated biphenyls (PCB). The detection limit for volatile organics ranges from 1 to 50 parts per trillion. Only trace quantities of organics are detected, the DOP levels do not exceed 2.5 ng cu m and the PCB levels do not exceed 454 ng cu m.

  11. Institutional Tuberculosis Transmission. Controlled Trial of Upper Room Ultraviolet Air Disinfection: A Basis for New Dosing Guidelines

    PubMed Central

    Mphaphlele, Matsie; Dharmadhikari, Ashwin S.; Jensen, Paul A.; Rudnick, Stephen N.; van Reenen, Tobias H.; Pagano, Marcello A.; Leuschner, Wilhelm; Sears, Tim A.; Milonova, Sonya P.; van der Walt, Martie; Stoltz, Anton C.; Weyer, Karin

    2015-01-01

    Rationale: Transmission is driving the global tuberculosis epidemic, especially in congregate settings. Worldwide, natural ventilation is the most common means of air disinfection, but it is inherently unreliable and of limited use in cold climates. Upper room germicidal ultraviolet (UV) air disinfection with air mixing has been shown to be highly effective, but improved evidence-based dosing guidelines are needed. Objectives: To test the efficacy of upper room germicidal air disinfection with air mixing to reduce tuberculosis transmission under real hospital conditions, and to define the application parameters responsible as a basis for proposed new dosing guidelines. Methods: Over an exposure period of 7 months, 90 guinea pigs breathed only untreated exhaust ward air, and another 90 guinea pigs breathed only air from the same six-bed tuberculosis ward on alternate days when upper room germicidal air disinfection was turned on throughout the ward. Measurements and Main Results: The tuberculin skin test conversion rates (>6 mm) of the two chambers were compared. The hazard ratio for guinea pigs in the control chamber converting their skin test to positive was 4.9 (95% confidence interval, 2.8–8.6), with an efficacy of approximately 80%. Conclusions: Upper room germicidal UV air disinfection with air mixing was highly effective in reducing tuberculosis transmission under hospital conditions. These data support using either a total fixture output (rather than electrical or UV lamp wattage) of 15–20 mW/m3 total room volume, or an average whole-room UV irradiance (fluence rate) of 5–7 μW/cm2, calculated by a lighting computer-assisted design program modified for UV use. PMID:25928547

  12. Simulation of effects of direction and air flow speed on temperature distribution in the room covered by various roof materials

    NASA Astrophysics Data System (ADS)

    Sukanto, H.; Budiana, E. P.; Putra, B. H. H.

    2016-03-01

    The objective of this research is to get a comparison of the distribution of the room temperature by using three materials, namely plastic-rubber composite, clay, and asbestos. The simulation used Ansys Fluent to get the temperature distribution. There were two conditions in this simulations, first the air passing beside the room and second the air passing in front of the room. Each condition will be varied with the air speed of 1 m/s, 2 m/s, 3 m/s, 4 m/s, 5 m/s for each material used. There are three heat transfers in this simulation, namely radiation, convection, and conduction. Based on the ANSI/ ASHRAE Standard 55-2004, the results of the simulation showed that the best temperature distribution was the roof of plastic-rubber composites.

  13. Concentrated Solar Air Conditioning for Buildings Project

    NASA Technical Reports Server (NTRS)

    McLaughlin, Rusty

    2010-01-01

    This slide presentation reviews project to implement the use of solar power to provide air conditioning for NASA buildings. Included is an overall conceptual schematic, and an diagram of the plumbing and instrumentation for the project. The use of solar power to power air conditioning in buildings, particularly in the Southwest, could save a significant amount of money. DOD studies have concluded that air conditioning accounts for 30-60% of total energy expenditures.

  14. Passive inhalation of marijuana smoke: urinalysis and room air levels of delta-9-tetrahydrocannabinol.

    PubMed

    Cone, E J; Johnson, R E; Darwin, W D; Yousefnejad, D; Mell, L D; Paul, B D; Mitchell, J

    1987-01-01

    In two separate studies, 5 drug-free male volunteers with a history of marijuana use were passively exposed to the sidestream smoke of 4 and 16 marijuana cigarettes (2.8% delta-9-tetrahydrocannabinol [THC]) for 1 h each day for 6 consecutive days. A third study was similarly performed with 2 marijuana-naive subjects passively exposed to the smoke of 16 marijuana cigarettes. Passive smoke exposure was conducted in a small, unventilated room. Room air levels of THC and CO were monitored frequently. All urine specimens were collected and analyzed by EMIT d.a.u. assay, Abuscreen radioimmunoassay and GC/MS. The studies show that significant amounts of THC were absorbed by all subjects at the higher level of passive smoke exposure (eg., smoke from 16 marijuana cigarettes), resulting in urinary excretion of significant amounts of cannabinoid metabolites. However, it seems improbable that subjects would unknowingly tolerate the noxious smoke conditions produced by this exposure. At the lower level of passive marijuana-smoke exposure, specimens tested positive only infrequently or were negative. Room air levels of THC during passive smoke exposure appeared to be the most critical factor in determining whether a subject produced cannabinoid-positive urine specimens. PMID:3037193

  15. Passive inhalation of marijuana smoke: urinalysis and room air levels of delta-9-tetrahydrocannabinol

    SciTech Connect

    Cone, E.J.; Johnson, R.E.; Darwin, W.D.; Yousefnejad, D.; Mell, L.D.; Paul, B.D.; Mitchell, J.

    1987-05-01

    In two separate studies, 5 drug-free male volunteers with a history of marijuana use were passively exposed to the sidestream smoke of 4 and 16 marijuana cigarettes (2.8% delta-9-tetrahydrocannabinol (THC)) for 1 h each day for 6 consecutive days. A third study was similarly performed with 2 marijuana-naive subjects passively exposed to the smoke of 16 marijuana cigarettes. Passive smoke exposure was conducted in a small, unventilated room. Room air levels of THC and CO were monitored frequently. All urine specimens were collected and analyzed by EMIT d.a.u. assay, Abuscreen radioimmunoassay and GC/MS. The studies show that significant amounts of THC were absorbed by all subjects at the higher level of passive smoke exposure (eg., smoke from 16 marijuana cigarettes), resulting in urinary excretion of significant amounts of cannabinoid metabolites. However, it seems improbable that subjects would unknowingly tolerate the noxious smoke conditions produced by this exposure. At the lower level of passive marijuana-smoke exposure, specimens tested positive only infrequently or were negative. Room air levels of THC during passive smoke exposure appeared to be the most critical factor in determining whether a subject produced cannabinoid-positive urine specimens.

  16. 8. VIEW OF ROOM 101 (ASSEMBLY ROOM) FROM NORTHEAST CORNER ...

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

    8. VIEW OF ROOM 101 (ASSEMBLY ROOM) FROM NORTHEAST CORNER SHOWING FLEXIBLE AIR-CONDITIONING DUCT - Vandenberg Air Force Base, Space Launch Complex 3, Vehicle Support Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  17. Air Conditioning. Performance Objectives. Intermediate Course.

    ERIC Educational Resources Information Center

    Long, William

    Several intermediate performance objectives and corresponding criterion measures are listed for each of seven terminal objectives for an intermediate air conditioning course. The titles of the seven terminal objectives are Refrigeration Cycle, Job Requirement Skills, Air Conditioning, Trouble Shooting, Performance Test, Shop Management, and S.I.E.…

  18. HEATING AND AIR CONDITIONING EDUCATIONAL PROGRAM.

    ERIC Educational Resources Information Center

    Lennox Industries, Inc., Marshalltown, IA.

    INCREASED MOTIVATION, INCREASED INITIAL COMPREHENSION, AND INCREASED RETENTION ARE THE PRIME GOALS OF THE LENNOX HEATING AND AIR CONDITIONING EDUCATION PROGRAM. IT IS A COMPLETE PROGRAM WITH ALL THE TEACHING TOOLS REQUIRED TO PRODUCE A KNOWLEDGEABLE HEATING AND AIR-CONDITIONING INSTALLER OR SERVICE MAN. THIS INSTRUCTIONAL PROGRAM IS DESIGNED…

  19. Air Conditioning. FOS: Fundamentals of Service.

    ERIC Educational Resources Information Center

    Employment and Training Administration (DOL), Washington, DC. Office of Youth Programs.

    This manual on air conditioning is one of a series of power mechanics texts and visual aids covering theory of operation, diagnosis, and repair. Information is presented for use by vocational students and teachers as well as shop servicemen and laymen. Focus is on air conditioning systems for mobile machines, but most of the information also…

  20. Air Conditioning and Heating Technology--II.

    ERIC Educational Resources Information Center

    Gattone, Felix

    Twenty-eight chapters and numerous drawings provide information for instructors and students of air conditioning and heating technology. Chapter 1 lists the occupational opportunities in the field. Chapter 2 covers the background or development of the industry of air conditioning and heating technology. Chapter 3 includes some of the principle…

  1. Oxygen enrichment of room air to improve well-being and productivity at high altitude.

    PubMed

    West, J B

    1999-01-01

    Increasingly, commercial activities, such as mines, and scientific facilities, such as telescopes, are being placed at very high altitudes, up to 5,000 m. Frequently workers commute to these locations from much lower altitudes, or even from sea level. In addition, large numbers of people permanently live and work at high altitudes. The hypoxia of high altitude impairs sleep quality, mental performance, productivity, and general well-being. Recently it has become feasible to raise the oxygen concentration of room air by injecting oxygen into the air conditioning. This is remarkably effective at reducing the equivalent altitude. For example, increasing the oxygen concentration by 1% (e.g., from 21% to 22%) reduces the equivalent altitude by about 300 m. In other words, a room at an altitude of 4,500 m containing 26% oxygen is effectively at an altitude of 3,000 m. Oxygen enrichment has now been tested in several studies and shown to improve sleep quality and cognitive function. The fire hazard is less than in air at sea level. This innovative technique promises to improve productivity and well-being at high altitude. PMID:10441257

  2. Effect of room air recirculation delay on the decay rate of tracer gas concentration

    SciTech Connect

    Kristoffersen, A.R.; Gadgil, A.J.; Lorenzetti, D.M.

    2004-05-01

    Tracer gas measurements are commonly used to estimate the fresh air exchange rate in a room or building. Published tracer decay methods account for fresh air supply, infiltration, and leaks in ductwork. However, the time delay associated with a ventilation system recirculating tracer back to the room also affects the decay rate. We present an analytical study of tracer gas decay in a well-mixed, mechanically-ventilated room with recirculation. The analysis shows that failing to account for delays can lead to under- or over-estimates of the fresh air supply, depending on whether the decay rate calculation includes the duct volume.

  3. Mine ventilation and air conditioning. 3. edition

    SciTech Connect

    Hartman, H.L.; Mutmansky, J.M.; Ramani, R.V.; Wang, Y.J.

    1998-12-31

    This revised edition presents an engineering design approach to ventilation and air conditioning as part of the comprehensive environmental control of the mine atmosphere. It provides an in-depth look, for practitioners who design and operate mines, into the health and safety aspects of environmental conditions in the underground workplace. The contents include: Environmental control of the mine atmosphere; Properties and behavior of air; Mine air-quality control; Mine gases; Dusts and other mine aerosols; Mine ventilation; Airflow through mine openings and ducts; Mine ventilation circuits and networks; Natural ventilation; Fan application to mines; Auxiliary ventilation and controlled recirculation; Economics of airflow; Control of mine fires and explosions; Mine air conditioning; Heat sources and effect in mines; Mine air conditioning systems; Appendices; References; Answers to selected problems; and Index.

  4. Breakthrough Video: Desiccant Enhanced Evaporative Air Conditioning

    SciTech Connect

    2012-01-01

    Researchers at the National Renewable Energy Laboratory (NREL) invented a breakthrough technology that improves air conditioning in a novel way—with heat. NREL combined desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90% less electricity and up to 80% less total energy than traditional air conditioning (AC). This solution, called the desiccant enhanced evaporative air conditioner (DEVAP), also controls humidity more effectively to improve the comfort of people in buildings.

  5. Troubleshooting the residential air conditioning system

    SciTech Connect

    Puzio, H.

    1996-01-01

    In order to effectively diagnose problems in a residential air conditioning system, the technician should develop and follow a logical step-by-step troubleshooting procedure. A list of problems, along with possible causes and solutions, that a technician may encounter when servicing a residential air conditioner is presented.

  6. USE OF EMERGENCY ROOM PATIENT POPULATIONS IN AIR POLLUTION EPIDEMIOLOGY

    EPA Science Inventory

    The long-term objective of this project was the design and implementation of a particular epidemiological approach to investigation of ambient pollutant effects: the correlation of pollutant exposure with patterns of hospital emergency room utilization. The report covers the init...

  7. Use of a portable air disinfecting system to remove seeded coliphage in hospital rooms.

    PubMed

    Verhougstraete, Marc; Reynolds, Kelly

    2016-06-01

    Health care-associated infections are a major problem worldwide, and the airborne route is believed to be a contributory source of secondary health care-associated infections. This study examined the efficacy of a portable air disinfecting system to remove seeded coliphage virus from the air in hospitals rooms. Aerosolized coliphage concentrations were not statistically different between treatment and no treatment measurements. However, future research should focus on additional investigations in the patient rooms that incorporate fomite and air testing alongside portable air filtration devices. PMID:26905789

  8. A Well-Mixed Computational Model for Estimating Room Air Levels of Selected Constituents from E-Vapor Product Use

    PubMed Central

    Rostami, Ali A.; Pithawalla, Yezdi B.; Liu, Jianmin; Oldham, Michael J.; Wagner, Karl A.; Frost-Pineda, Kimberly; Sarkar, Mohamadi A.

    2016-01-01

    Concerns have been raised in the literature for the potential of secondhand exposure from e-vapor product (EVP) use. It would be difficult to experimentally determine the impact of various factors on secondhand exposure including, but not limited to, room characteristics (indoor space size, ventilation rate), device specifications (aerosol mass delivery, e-liquid composition), and use behavior (number of users and usage frequency). Therefore, a well-mixed computational model was developed to estimate the indoor levels of constituents from EVPs under a variety of conditions. The model is based on physical and thermodynamic interactions between aerosol, vapor, and air, similar to indoor air models referred to by the Environmental Protection Agency. The model results agree well with measured indoor air levels of nicotine from two sources: smoking machine-generated aerosol and aerosol exhaled from EVP use. Sensitivity analysis indicated that increasing air exchange rate reduces room air level of constituents, as more material is carried away. The effect of the amount of aerosol released into the space due to variability in exhalation was also evaluated. The model can estimate the room air level of constituents as a function of time, which may be used to assess the level of non-user exposure over time. PMID:27537903

  9. A Well-Mixed Computational Model for Estimating Room Air Levels of Selected Constituents from E-Vapor Product Use.

    PubMed

    Rostami, Ali A; Pithawalla, Yezdi B; Liu, Jianmin; Oldham, Michael J; Wagner, Karl A; Frost-Pineda, Kimberly; Sarkar, Mohamadi A

    2016-01-01

    Concerns have been raised in the literature for the potential of secondhand exposure from e-vapor product (EVP) use. It would be difficult to experimentally determine the impact of various factors on secondhand exposure including, but not limited to, room characteristics (indoor space size, ventilation rate), device specifications (aerosol mass delivery, e-liquid composition), and use behavior (number of users and usage frequency). Therefore, a well-mixed computational model was developed to estimate the indoor levels of constituents from EVPs under a variety of conditions. The model is based on physical and thermodynamic interactions between aerosol, vapor, and air, similar to indoor air models referred to by the Environmental Protection Agency. The model results agree well with measured indoor air levels of nicotine from two sources: smoking machine-generated aerosol and aerosol exhaled from EVP use. Sensitivity analysis indicated that increasing air exchange rate reduces room air level of constituents, as more material is carried away. The effect of the amount of aerosol released into the space due to variability in exhalation was also evaluated. The model can estimate the room air level of constituents as a function of time, which may be used to assess the level of non-user exposure over time. PMID:27537903

  10. Reduced bleed air extraction for DC-10 cabin air conditioning

    NASA Technical Reports Server (NTRS)

    Newman, W. H.; Viele, M. R.; Hrach, F. J.

    1980-01-01

    It is noted that a significant fuel savings can be achieved by reducing bleed air used for cabin air conditioning. Air in the cabin can be recirculated to maintain comfortable ventilation rates but the quality of the air tends to decrease due to entrainment of smoke and odors. Attention is given to a development system designed and fabricated under the NASA Engine Component Improvement Program to define the recirculation limit for the DC-10. It is shown that with the system, a wide range of bleed air reductions and recirculation rates is possible. A goal of 0.8% fuel savings has been achieved which results from a 50% reduction in bleed extraction from the engine.

  11. Development of a Ventilation and Air-conditioning System using Fixed Bed Desiccant Units

    NASA Astrophysics Data System (ADS)

    Miyazaki, Takahiko; Akisawa, Atsushi; Ueda, Yuki; Shindoh, Shinji; Godo, Masazumi; Takatsuka, Takeshi

    The study investigated fixed bed desiccant units for ventilation and air-conditioning. The role of the system is the dehumidification of the outdoor fresh air to be supplied to an air-conditioned room. Hence, the latent heat load of the air-conditioner in the room can be mitigated. The system consisted of two pairs of a desiccant unit and a heat storage unit. The microwave irradiation to the desiccant unit was examined as a candidate of the regeneration method of the system, and the performance of the microwave regeneration was compared with that of the hot air regeneration in terms of the supply air humidity ratio, outdoor air based COP, and the process air temperatures. The results revealed the effects of the switching time and the irradiation timing on the performance of the microwave irradiation.

  12. Disinfection of indoor air microorganisms in stack room of university library using gaseous chlorine dioxide.

    PubMed

    Hsu, Ching-Shan; Lu, Ming-Chun; Huang, Da-Ji

    2015-02-01

    As with all indoor public spaces in Taiwan, the stack rooms in public libraries should meet the air quality guidelines laid down by the Taiwan Environmental Protection Administration. Accordingly, utilizing a university library in Taiwan for experimental purposes, this study investigates the efficiency of gaseous chlorine dioxide (ClO2) as a disinfection agent when applied using three different treatment modes, namely a single-daily disinfection mode (SIM), a twice-daily disinfection mode (TWM), and a triple-daily disinfection mode (TRM). For each treatment mode, the ClO2 is applied using an ultrasonic aerosol device and is performed both under natural lighting conditions and under artificial lighting conditions. The indoor air quality is evaluated before and after each treatment session by measuring the bioaerosol levels of bacteria and fungi. The results show that for all three disinfection modes, the application of ClO2 reduces the indoor bacteria and fungi concentrations to levels lower than those specified by the Taiwan EPA (i.e., bacteria <1500 CFU/m(3), fungi <1000 CFU/m(3)), irrespective of the lighting conditions under which the disinfection process is performed. For each disinfection mode, a better disinfection efficiency is obtained under natural lighting conditions since ClO2 readily decomposes under strong luminance levels. Among the three treatment modes, the disinfection efficiencies of the TWM and TRM modes are very similar under natural lighting conditions and are significantly better than that of the SIM mode. Thus, overall, the results suggest that the TWM treatment protocol represents the most cost-effective and efficient method for meeting the indoor air quality requirements of the Taiwan EPA. PMID:25626564

  13. A strategy for oxygen conditioning at high altitude: comparison with air conditioning.

    PubMed

    West, John B

    2015-09-15

    Large numbers of people live or work at high altitude, and many visit to trek or ski. The inevitable hypoxia impairs physical working capacity, and at higher altitudes there is also cognitive impairment. Twenty years ago oxygen enrichment of room air was introduced to reduce the hypoxia, and this is now used in dormitories, hotels, mines, and telescopes. However, recent advances in technology now allow large amounts of oxygen to be obtained from air or cryogenic oxygen sources. As a result it is now feasible to oxygenate large buildings and even institutions such as hospitals. An analogy can be drawn between air conditioning that has improved the living and working conditions of millions of people who live in hot climates and oxygen conditioning that can do the same at high altitude. Oxygen conditioning is similar to air conditioning except that instead of cooling the air, the oxygen concentration is raised, thus reducing the equivalent altitude. Oxygen conditioning on a large scale could transform living and working conditions at high altitude, where it could be valuable in homes, hospitals, schools, dormitories, company headquarters, banks, and legislative settings. PMID:26139219

  14. 76 FR 19913 - Compliance Testing Procedures: Correction Factor for Room Air Conditioners

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-11

    ... contained in the petition. (75 FR 72739, Nov. 26, 2010). In addition to a comment from AHAM reiterating... that as atmospheric pressure drops, so does the air density and, therefore, the mass of air in a room. As atmospheric pressure drops, the efficiency of a unit would also drop because there would be...

  15. Thermal analysis of car air conditioning

    NASA Astrophysics Data System (ADS)

    Trzebiński, Daniel; Szczygieł, Ireneusz

    2010-10-01

    Thermodynamic analysis of car air cooler is presented in this paper. Typical refrigerator cycles are studied. The first: with uncontrolled orifice and non controlled compressor and the second one with the thermostatic controlled expansion valve and externally controlled compressor. The influence of the refrigerant decrease and the change of the air temperature which gets to exchangers on the refrigeration efficiency of the system; was analysed. Also, its effectiveness and the power required to drive the compressor were investigated. The impact of improper refrigerant charge on the performance of air conditioning systems was also checked.

  16. Test Protocol for Room-to-Room Distribution of Outside Air by Residential Ventilation Systems

    SciTech Connect

    Barley, C. D.; Anderson, R.; Hendron, B.; Hancock, E.

    2007-12-01

    This test and analysis protocol has been developed as a practical approach for measuring outside air distribution in homes. It has been used successfully in field tests and has led to significant insights on ventilation design issues. Performance advantages of more sophisticated ventilation systems over simpler, less-costly designs have been verified, and specific problems, such as airflow short-circuiting, have been identified.

  17. The Effect of Computers on School Air-Conditioning.

    ERIC Educational Resources Information Center

    Fickes, Michael

    2000-01-01

    Discusses the issue of increased air-conditioning demand when schools equip their classrooms with computers that require enhanced and costlier air-conditioning systems. Air-conditioning costs are analyzed in two elementary schools and a middle school. (GR)

  18. ALTERNATIVE TECHNOLOGIES FOR REFRIGERATION AND AIR-CONDITIONING APPLICATIONS

    EPA Science Inventory

    The report gives results of an assessment of refrigeration technologies that are alternatives to vapor compression refrigeration for use in five application categories: domestic air conditioning, commercial air conditioning, mobile air conditioning, domestic refrigeration, and co...

  19. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System.

    PubMed

    Zhao, Baiwang; Peng, Na; Liang, Canzeng; Yong, Wai Fen; Chung, Tai-Shung

    2015-01-01

    In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18-22 g/m³ to a range of 13.5-18.3 g/m³. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process. PMID:26580660

  20. Hollow Fiber Membrane Dehumidification Device for Air Conditioning System

    PubMed Central

    Zhao, Baiwang; Peng, Na; Liang, Canzeng; Yong, Wai Fen; Chung, Tai-Shung

    2015-01-01

    In order to provide a comfortable living and working environment indoors in tropical countries, the outdoor air often needs to be cooled and dehumidified before it enters the rooms. Membrane separation is an emerging technology for air dehumidification and it is based on the solution diffusion mechanism. Water molecules are preferentially permeating through the membranes due to its smaller kinetic diameter and higher condensability than the other gases. Compared to other dehumidification technologies such as direct cooling or desiccation, there is no phase transition involved in membrane dehumidification, neither the contact between the fresh air stream and the desiccants. Hence, membrane dehumidification would not only require less energy consumption but also avoid cross-contamination problems. A pilot scale air dehumidification system is built in this study which comprises nine pieces of one-inch PAN/PDMS hollow fiber membrane modules. A 150 h long-term test shows that the membrane modules has good water vapor transport properties by using a low vacuum force of only 0.78 bar absolute pressure at the lumen side. The water vapor concentration of the feed humid air decreases dramatically from a range of 18–22 g/m3 to a range of 13.5–18.3 g/m3. Most importantly, the total energy saving is up to 26.2% compared with the conventional air conditioning process. PMID:26580660

  1. Automobile air-conditioning unit. Final report

    SciTech Connect

    Schaetzle, W.J.

    1982-12-01

    In this study the refrigerant in the automobile air-conditioner is compressed by thermal energy in a unique compression system rather than by work in a standard compressor. The compression uses an intermittent compression process with a solid absorbent. The vapor is absorbed by an absorbent at relatively low temperature and ejected as the absorbent temperature is raised. A set of one way valves limits flow to one direction. Major contributions are heat transfer requirements, molecular sieve-refrigerant matching, minimizing non-producing mass, solving thermal fatigue and shock problems, and applying this to automobile air-conditioning. The performance study shows energy savings up to fifty percent are possible, depending on engine load. A twenty percent energy savings with the vehicle tested with the air-conditioner in operation is average. The study also showed that less fuel is used with the windows open than with the air-conditioner operating.

  2. TEWI Evaluation for Household Refrigeration and Air-Conditioning Systems

    NASA Astrophysics Data System (ADS)

    Sobue, Atsushi; Watanabe, Koichi

    In the present study, we have quantitatively evaluated the global warming impact by household refrigerator and air-conditioning systems on the basis of reliable TEWI information. In TEWI evaluation of household refrigerators, the percentage of the impact by refrigerant released to the atmosphere (direct effect) is less than 18.6% in TEWI. In case of room air-conditioners, however, the percentage of direct effect is less than 5.4% in TEWI. Therefore, it was confirmed that impact by CO2 released as a result of the energy consumed to drive the refrigeration or air-conditioning systems throughout their lifetime (indirect effect) is far larger than direct effect by the entire system. A reduction of indirect effect by energy saving is the most effective measure in reducing the global warming impact by refrigeration and air-conditioning systems, For a realization of the energy saving, not only the advanced improvement in energy efficiency by household appliance manufacturers but also the improvement of consumer's mind in selecting the systems and a way of using are concluded important.

  3. Air, water, and surface bacterial contamination in a university-hospital autopsy room.

    PubMed

    Maujean, Géraldine; Malicier, Daniel; Fanton, Laurent

    2012-03-01

    Today, little is known about the bacteriological environment of the autopsy room and its potential interest for medico-legal practices. Seven hundred fifty microbiological samples were taken from surface (n = 660), air (n = 48), and water (n = 42) to evaluate it in a French University Forensic Department. Median bacterial counts were compared before and during autopsy for air samples, and before and after autopsy for surface samples, using Wilcoxon matched pairs signed ranks test. Bacterial identification relied on traditional phenotypic methods. Bacterial counts in the air were low before autopsy, increased significantly during procedure, and seemed more linked to the number of people in the room than to an important production of aerosol-containing bacteria. Despite cleaning, human fecal flora was omnipresent on surfaces, which revealed insufficient disinfection. Bacteriological sampling is an easy way to monitor cleaning practices in postmortem rooms, but chiefly a way to improve the reliability of medico-legal proofs of infectious deaths. PMID:22309163

  4. MOBILE AIR-CONDITIONING RECYCLING MANUAL

    EPA Science Inventory

    The report gives guidelines on the recovery and recycle of the chlorofluorocarbon (CFC), dichlorodifluoromethane (CFC-12), from mobile air conditions. It is intended for wide distribution internationally and is especially for use by developing countries and the World Bank to ass...

  5. Standardized Curriculum for Heating and Air Conditioning.

    ERIC Educational Resources Information Center

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    Standardized vocational education course titles and core contents for two courses in Mississippi are provided: heating and air conditioning I and II. The first course contains the following units: (1) orientation; (2) safety; (3) refrigeration gauges and charging cylinder; (4) vacuum pump service operations; (5) locating refrigerant leaks; (6)…

  6. Solar powered desiccant air conditioning system

    NASA Astrophysics Data System (ADS)

    1981-07-01

    A solar-powered desiccant air conditioning system using silica gel was developed, and modifications to the existing unit and additional testing are proposed to demonstrate the feasibility of the unit. Conversion from a rotating bed to a fixed bed of silica gel is proposed. Some general plans for commercialization are briefly discussed.

  7. Air Conditioning and Refrigeration Book IV.

    ERIC Educational Resources Information Center

    Eckes, William; Fulkerson, Dan

    This publication is the concluding text in a four-part curriculum for air conditioning and refrigeration. Materials in Book 4 are designed to complement theoretical and functional elements in Books 1-3. Instructional materials in this publication are written in terms of student performance using measurable objectives. The course includes six…

  8. Air Conditioning and Refrigeration Supplementary Units.

    ERIC Educational Resources Information Center

    Winston, Del; And Others

    This document contains supplemental materials for special needs high school students intended to facilitate their mainstreaming in regular air conditioning and refrigeration courses. Teacher's materials precede the materials for students and include general notes for the instructor, additional suggestions, two references, a questionnaire on the…

  9. Readings in Air Conditioning and Refrigeration.

    ERIC Educational Resources Information Center

    Uberto, Jeffrey A.

    Designed to encourage vocational high school students to read by offering reading materials relevant to their vocational goals, this document contains thirty-seven articles related to air conditioning and refrigeration which have been selected from trade journals, magazines, and newspapers and adapted to the students' reading capabilities. A…

  10. Fundamentals of Air Conditioning and Refrigeration.

    ERIC Educational Resources Information Center

    Clemons, Mark

    This set of instructional materials provides secondary and postsecondary students with a state-of-the-art curriculum for the air conditioning and refrigeration industry that includes the many changes brought by new Environmental Protection Agency (EPA) regulations. Introductory materials explain the use of this publication and provide the…

  11. Air Conditioning and Refrigeration. Book One.

    ERIC Educational Resources Information Center

    Wantiez, Gary W.

    Designed to provide students with the basic skills for an occupation in air conditioning and refrigeration, this curriculum guide includes seven major areas, each consisting of one or more units of instruction. These areas and their respective units are titled as follows: Orientation (history and development, and job opportunities), Safety…

  12. Air Conditioning and Refrigeration Book III.

    ERIC Educational Resources Information Center

    Eckes, William; Fulkerson, Dan

    Designed to present theory as a functional aspect, this air conditioning and refrigeration curriculum guide is comprised of nine units of instruction. Unit titles include (1) Job Orientation, (2) Applying for a Job, (3) Customer Relations, (4) Business Management, (5) Psychometrics, (6) Residential Heat Loss and Heat Gain, (7) Duct Design and…

  13. Air Conditioning and Refrigeration. Book Two.

    ERIC Educational Resources Information Center

    Wantiez, Gary W.

    This curriculum guide (book II), along with book I, is designed to provide students with the basic skills for an occupation in air conditioning and refrigeration. Six major areas are included, each consisting of one or more units of instruction. These areas and their respective units are titled as follows: Electricity (fundamentals of electricity,…

  14. Metrics for Air Conditioning & Refrigeration, Heating, Ventilating.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of the air conditioning and refrigeration, heating and ventilating student, this instructional package is one of three for the construction occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already…

  15. Objective Volumetric Comparison of Room Air versus Carbon Dioxide for Colonic Distention at Screening CT Colonography

    PubMed Central

    Patrick, James L.; Bakke, Joshua R.; Bannas, Peter; Kim, David H.; Lubner, Meghan G.; Pickhardt, Perry J.

    2014-01-01

    Purpose To objectively compare colonic distention at CT colonography (CTC) achieved with manual room air versus automated low-pressure carbon dioxide using a novel automated volumetric quality assessment tool. Methods Volumetric analysis was retrospectively performed on CTC studies in 300 asymptomatic adults using an automated quality assessment tool (V3D Colon [beta version], Viatronix). Colonic distention was achieved with room air self-administered to tolerance via hand-held pump (mean number of pumps, 39 ± 32) in 150 individuals (mean age, 59 years; 98 men, 51 women) and via continuous low-pressure automated infusion of carbon dioxide in 150 individuals (mean age, 57 years; 89 men, 61 women). CTC studies in supine and prone position were assessed to determine total colonic volume (luminal gas and fluid). The colonic length along the automated centerline was also recorded to enable calculation of length-adjusted colonic volumes. Results The mean total colonic volume (± SD) for individuals receiving room air and carbon dioxide distention was 1809± 514 mL and 2223 ± 686 mL, respectively (p<0.01). The prone position was better distended in 78.7% (118/150) of cases using room air; whereas, the supine was better in 66.0% (99/150) of carbon dioxide cases (p<0.01). Using a volume threshold of 2000 ml, 49 (32.7%) of room air cases and 92 (61.3%) of CO2 cases were above this cut-off. The mean length-adjusted colonic volume (mL/cm) for the room air and carbon dioxide techniques was 9.9 ± 2.4 mL/cm and 11.6 ± 2.6 mL/cm (p<0.01). Conclusions Using automated volumetry allowed quantitative analyses of colonic volumes and objectively confirmed that continuous low-pressure carbon dioxide provides greater overall colonic distention than the manual room air technique at CTC. The supine position demonstrated better distention with carbon dioxide, whereas the prone position was better distended with the room air technique. PMID:25081924

  16. Air Conditioning System using Rankine Cycle

    NASA Astrophysics Data System (ADS)

    Nagatomo, Shigemi; Yamaguchi, Hiroichi; Hattori, Hitoshi; Futamura, Motonori

    Natural gas is used as the energy source to cope with the recent situation of increasing demand for electricity especially in summer. In this paper, the performance of a Rankine cycle air conditioning system driven by natural gas was studied. The following results were obtained : (1) Basic equations of performance, refrigerant mass flow rate and expander volume were developed by using the values of heating efficiency, regeneration efficiency, expander efficiency and compressor efficiency. (2) R134a refrigerant has been considered to be suitable for the Rankine cycle air conditioning system, compared with other refrigerants. (3)A Rankine cycle cooling system using R134a refrigerant as a single working fluid was developed. System COP of 0.47 was attained at typical operating condition.

  17. Quantitative assessment of bio-aerosols contamination in indoor air of University dormitory rooms

    PubMed Central

    Hayleeyesus, Samuel Fekadu; Ejeso, Amanuel; Derseh, Fikirte Aklilu

    2015-01-01

    Objectives The purpose of this study is to provide insight into how students are exposed to indoor bio-aerosols in the dormitory rooms and to figure out the major possible factors that govern the contamination levels. Methodology The Bio-aerosols concentration level of indoor air of thirty dormitory rooms of Jimma University was determined by taking 120 samples. Passive air sampling technique; the settle plate method using open Petri-dishes containing different culture media was employed to collect sample twice daily. Results The range of bio-aerosols contamination detected in the dormitory rooms was 511–9960 CFU/m3 for bacterial and 531–6568 CFU/m3 for fungi. Based on the criteria stated by WHO expert group, from the total 120 samples 95 of the samples were above the recommended level. The statistical analysis showed that, occupancy were significantly affected the concentrations of bacteria that were measured in all dormitory rooms at 6:00 am sampling time (p-value=0.000) and also the concentrations of bacteria that were measured in all dormitory rooms were significantly different to each other (p-value=0.013) as of their significance difference in occupancy (p-value=0.000). Moreover, there were a significant different on the contamination level of bacteria at 6:00 am and 7:00 pm sampling time (p=0.015), whereas there is no significant difference for fungi contamination level for two sampling times (p= 0.674). Conclusion There is excessive bio-aerosols contaminant in indoor air of dormitory rooms of Jimma University and human occupancy produces a marked concentration increase of bacterial contamination levels and most fungi species present into the rooms air of Jimma University dormitory were not human-borne. PMID:26609289

  18. Alternative Air Conditioning Technologies: Underfloor AirDistribution (UFAD)

    SciTech Connect

    Webster, Tom

    2004-06-01

    Recent trends in today's office environment make it increasingly more difficult for conventional centralized HVAC systems to satisfy the environmental preferences of individual officer workers using the standardized approach of providing a single uniform thermal and ventilation environment. Since its original introduction in West Germany during the 1950s, the open plan office containing modular workstation furniture and partitions is now the norm. Thermostatically controlled zones in open plan offices typically encompass relatively large numbers of workstations in which a diverse work population having a wide range of preferred temperatures must be accommodated. Modern office buildings are also being impacted by a large influx of heat-generating equipment (computers, printers, etc.) whose loads may vary considerably from workstation to workstation. Offices are often reconfigured during the building's lifetime to respond to changing tenant needs, affecting the distribution of within-space loads and the ventilation pathways among and over office partitions. Compounding this problem, there has been a growing awareness of the importance of the comfort, health, and productivity of individual office workers, giving rise to an increased demand among employers and employees for a high-quality work environment. During recent years an increasing amount of attention has been paid to air distribution systems that individually condition the immediate environments of office workers within their workstations to address the issues outlined above. As with task/ambient lighting systems, the controls for the ''task'' components of these systems are partially or entirely decentralized and under the control of the occupants. Typically, the occupant has control over the speed and direction, and in some cases the temperature, of the incoming air supply. Variously called ''task/ambient conditioning,'' ''localized thermal distribution,'' and ''personalized air conditioning'' systems, these

  19. Urban air pollution and emergency room admissions for respiratory symptoms: a case-crossover study in Palermo, Italy

    PubMed Central

    2011-01-01

    Background Air pollution from vehicular traffic has been associated with respiratory diseases. In Palermo, the largest metropolitan area in Sicily, urban air pollution is mainly addressed to traffic-related pollution because of lack of industrial settlements, and the presence of a temperate climate that contribute to the limited use of domestic heating plants. This study aimed to investigate the association between traffic-related air pollution and emergency room admissions for acute respiratory symptoms. Methods From January 2004 through December 2007, air pollutant concentrations and emergency room visits were collected for a case-crossover study conducted in Palermo, Sicily. Risk estimates of short-term exposures to particulate matter and gaseous ambient pollutants including carbon monoxide, nitrogen dioxide, and sulfur dioxide were calculated by using a conditional logistic regression analysis. Results Emergency departments provided data on 48,519 visits for respiratory symptoms. Adjusted case-crossover analyses revealed stronger effects in the warm season for the most part of the pollutants considered, with a positive association for PM10 (odds ratio = 1.039, 95% confidence interval: 1.020 - 1.059), SO2 (OR = 1.068, 95% CI: 1.014 - 1.126), nitrogen dioxide (NO2: OR = 1.043, 95% CI: 1.021 - 1.065), and CO (OR = 1.128, 95% CI: 1.074 - 1.184), especially among females (according to an increase of 10 μg/m3 in PM10, NO2, SO2, and 1 mg/m3 in CO exposure). A positive association was observed either in warm or in cold season only for PM10. Conclusions Our findings suggest that, in our setting, exposure to ambient levels of air pollution is an important determinant of emergency room (ER) visits for acute respiratory symptoms, particularly during the warm season. ER admittance may be considered a good proxy to evaluate the adverse effects of air pollution on respiratory health. PMID:21489245

  20. Innovative Air Conditioning and Climate Control

    NASA Technical Reports Server (NTRS)

    Graf, John

    2015-01-01

    NASA needed to develop a desiccant wheel based humidity removal system to enable the long term testing of the Orion CO2 scrubber on the International Space Station. In the course of developing that system, we learned three things that are relevant to energy efficient air conditioning of office towers. NASA developed a conceptual design for a humidity removal system for an office tower environment. We are looking for interested partners to prototype and field test this concept.

  1. Numerical simulation and nasal air-conditioning

    PubMed Central

    Keck, Tilman; Lindemann, Jörg

    2011-01-01

    Heating and humidification of the respiratory air are the main functions of the nasal airways in addition to cleansing and olfaction. Optimal nasal air conditioning is mandatory for an ideal pulmonary gas exchange in order to avoid desiccation and adhesion of the alveolar capillary bed. The complex three-dimensional anatomical structure of the nose makes it impossible to perform detailed in vivo studies on intranasal heating and humidification within the entire nasal airways applying various technical set-ups. The main problem of in vivo temperature and humidity measurements is a poor spatial and time resolution. Therefore, in vivo measurements are feasible only to a restricted extent, solely providing single temperature values as the complete nose is not entirely accessible. Therefore, data on the overall performance of the nose are only based on one single measurement within each nasal segment. In vivo measurements within the entire nose are not feasible. These serious technical issues concerning in vivo measurements led to a large number of numerical simulation projects in the last few years providing novel information about the complex functions of the nasal airways. In general, numerical simulations merely calculate predictions in a computational model, e.g. a realistic nose model, depending on the setting of the boundary conditions. Therefore, numerical simulations achieve only approximations of a possible real situation. The aim of this review is the synopsis of the technical expertise on the field of in vivo nasal air conditioning, the novel information of numerical simulations and the current state of knowledge on the influence of nasal and sinus surgery on nasal air conditioning. PMID:22073112

  2. 21 CFR 878.5070 - Air-handling apparatus for a surgical operating room.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Air-handling apparatus for a surgical operating room. 878.5070 Section 878.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Therapeutic Devices §...

  3. 21 CFR 878.5070 - Air-handling apparatus for a surgical operating room.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Air-handling apparatus for a surgical operating room. 878.5070 Section 878.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Therapeutic Devices §...

  4. 21 CFR 878.5070 - Air-handling apparatus for a surgical operating room.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Air-handling apparatus for a surgical operating room. 878.5070 Section 878.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Therapeutic Devices §...

  5. 21 CFR 878.5070 - Air-handling apparatus for a surgical operating room.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Air-handling apparatus for a surgical operating room. 878.5070 Section 878.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Therapeutic Devices §...

  6. 21 CFR 878.5070 - Air-handling apparatus for a surgical operating room.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Air-handling apparatus for a surgical operating room. 878.5070 Section 878.5070 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Therapeutic Devices §...

  7. Seminar 14 - Desiccant Enhanced Air Conditioning: Desiccant Enhanced Evaporative Air Conditioning (Presentation)

    SciTech Connect

    Kozubal, E.

    2013-02-01

    This presentation explains how liquid desiccant based coupled with an indirect evaporative cooler can efficiently produce cool, dry air, and how a liquid desiccant membrane air conditioner can efficiently provide cooling and dehumidification without the carryover problems of previous generations of liquid desiccant systems. It provides an overview to a liquid desiccant DX air conditioner that can efficiently provide cooling and dehumidification to high latent loads without the need for reheat, explains how liquid desiccant cooling and dehumidification systems can outperform vapor compression based air conditioning systems in hot and humid climates, explains how liquid desiccant cooling and dehumidification systems work, and describes a refrigerant free liquid desiccant based cooling system.

  8. Indoor air flow and pollutant removal in a room with desk-top ventilation

    SciTech Connect

    Faulkner, D.; Fisk, W.J.; Sullivan, D.P.

    1993-04-01

    In a furnished experimental facility with three workstations separated by partitions, we studied indoor air flow patterns and tobacco smoke removal efficiency of a desk-top task ventilation system. The task ventilation system permits occupant control of the temperature, flow rate and direction of air supplied through two desk-mounted supply nozzles. In the configuration evaluated, air exited the ventilated space through a ceiling-mounted return grill. To study indoor air flow patterns, we measured the age of air at multiple indoor locations using the tracer gas step-up procedure. To study the intra-room transport of tobacco smoke particles and the efficiency of panicle removal by ventilation, a cigarette was smoked mechanically in one workstation and particle concentrations were measured at multiple indoor locations including the exhaust airstream. Test variables included the direction of air supply from the nozzles, supply nozzle area, supply flow rate and temperature, percent recirculation of chamber air, and internal heatloads. With nozzles pointed toward the occupants, 100% outside air supplied at the desk-top, and air supply rates of approximately 40 L/s per workstation, the age of air at the breathing level of ventilated workstations was approximately 30% less than the age of air that would occur throughout the test space with perfectly mixed indoor air. With smaller air supply rates and/or air supplied parallel to the edges of the desk, ages of air at breathing locations were not significantly lower than the age with perfect mixing. Indoor tobacco smoke particle concentrations at specific locations were generally within 12% of the average measured indoor concentration and concentrations of particles in the exhaust airstream were not significantly different from concentration of particles at breathing locations.

  9. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1“Active mode” means a mode in which the room air... 10 Energy 3 2012-01-01 2012-01-01 false Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY...

  10. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1“Active mode” means a mode in which the room air... 10 Energy 3 2013-01-01 2013-01-01 false Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY...

  11. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1 “Active mode” means a mode in which the room air... 10 Energy 3 2014-01-01 2014-01-01 false Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY...

  12. Alternative non-CFC mobile air conditioning

    SciTech Connect

    Mei, V.C.; Chen, F.C.; Kyle, D.M.

    1992-09-01

    Concern about the destruction of the global environment by chlorofluorocarbon (CFC) fluids has become an impetus in the search for alternative, non-CFC refrigerants and cooling methods for mobile air conditioning (MAC). While some alternative refrigerants have been identified, they are not considered a lasting solution because of their high global warming potential, which could result in their eventual phaseout. In view of this dilemma, environmentally acceptable alternative cooling methods have become important. This report, therefore, is aimed mainly at the study of alternative automotive cooling methodologies, although it briefly discusses the current status of alternative refrigerants. The alternative MACs can be divided into work-actuated and heat-actuated systems. Work-actuated systems include conventional MAC, reversed Brayton air cycle, rotary vane compressor air cycle, Stirling cycle, thermoelectric (TE) cooling, etc. Heat-actuated MACs include metal hydride cooling, adsorption cooling, ejector cooling, absorption cycle, etc. While we are better experienced with some work-actuated cycle systems, heat-actuated cycle systems have a high potential for energy savings with possible waste heat applications. In this study, each altemative cooling method is discussed for its advantages and its limits.

  13. Room Acoustic Conditions of Performers in AN Old Opera House

    NASA Astrophysics Data System (ADS)

    IANNACE, GINO; IANNIELLO, CARMINE; MAFFEI, LUIGI; ROMANO, ROSARIO

    2000-04-01

    Proposed objective criteria related to the acoustic conditions for instrumentalists and singers have not received a sufficiently wide consent yet. In spite of this situation, it is the opinion of the authors that the measurement of existing criteria is useful for analysis and comparison. This paper reports the results of various acoustic measurements carried out in the Teatro di San Carlo, Naples-Italy, with the aim of obtaining objective information about its acoustics for performers. A first set of measurements was carried out when the theater was fitted for a symphonic concert and a second one when it was fitted for an opera performance.

  14. Conditions for free-air laser communications in Buenos Aires

    NASA Astrophysics Data System (ADS)

    Sica, D. S.; Castro, E. H.

    2005-08-01

    The wavelength, availability, range and power budget of an infrared free-space laser communication system critically depend on the atmospheric channel, which in turn is closely related to local weather conditions. As a result, the atmospheric propagation characteristics of the transmission medium must be taken into account from the beginning in the design of a free-space laser communication link. The most important linear effects that affect the attenuation of laser beam propagation through the atmosphere are absorption, scattering and turbulence. Weather parameters such as humidity, temperature and visibility are essential in determining the performance of a free-space laser communication system. Based on weather data recorded in Buenos Aires city (Argentina) at every hour during two years and made available to us by the Servicio Meteorologico Nacional (National Meteorological Service of the Argentinean Air Force), we calculate attenuation of laser radiation for an horizontal transmission path of 1 km for a near infrared direct detection optical communication system. Then, with these results, we estimate link availability and draw conclusions about when it is more convenient to transfer information.

  15. Development of a Ventilation and Air-conditioning System using Fixed Bed Desiccant Units

    NASA Astrophysics Data System (ADS)

    Miyazaki, Takahiko; Akisawa, Atsushi; Shindoh, Shinji; Masazumi, Godo; Takeshi, Takatsuka; Hamamoto, Yoshinori; Mori, Hideo

    The study investigated fixed bed desiccant units for ventilation and air-conditioning. The system mainly dehumidifies the outdoor fresh air to be supplied to an air-conditioned room. Hence, the airconditioning load of the air-conditioner in the room can be mitigated. Several adsorbents were compared from the viewpoints of humidity ratio at the outlet of the desiccant unit, dehumidified quantity per unit volume, and dehumidified quantity per unit adsorbent mass. The performance of the desiccant unit was predicted by simulation which was validated by comparison with experiment. The results revealed the most suitable adsorbent to reduce the desiccant unit size. It was also found that the humidity ratio at the outlet of the desiccant unit could be lowered by shortening the dimensionless switching time.

  16. Refrigeration, Heating & Air Conditioning. Post Secondary Curriculum Guide.

    ERIC Educational Resources Information Center

    Garrison, Joe C.; And Others

    This curriculum guide was designed for use in postsecondary refrigeration, heating and air conditioning education programs in Georgia. Its purpose is to provide for the development of entry level skills in refrigeration, heating, and air conditioning in the areas of air conditioning knowledge, theoretical structure, tool usage, diagnostic ability,…

  17. Applied patent RFID systems for building reacting HEPA air ventilation system in hospital operation rooms.

    PubMed

    Lin, Jesun; Pai, Jar-Yuan; Chen, Chih-Cheng

    2012-12-01

    RFID technology, an automatic identification and data capture technology to provide identification, tracing, security and so on, was widely applied to healthcare industry in these years. Employing HEPA ventilation system in hospital is a way to ensure healthful indoor air quality to protect patients and healthcare workers against hospital-acquired infections. However, the system consumes lots of electricity which cost a lot. This study aims to apply the RFID technology to offer a unique medical staff and patient identification, and reacting HEPA air ventilation system in order to reduce the cost, save energy and prevent the prevalence of hospital-acquired infection. The system, reacting HEPA air ventilation system, contains RFID tags (for medical staffs and patients), sensor, and reacting system which receives the information regarding the number of medical staff and the status of the surgery, and controls the air volume of the HEPA air ventilation system accordingly. A pilot program was carried out in a unit of operation rooms of a medical center with 1,500 beds located in central Taiwan from Jan to Aug 2010. The results found the air ventilation system was able to function much more efficiently with less energy consumed. Furthermore, the indoor air quality could still keep qualified and hospital-acquired infection or other occupational diseases could be prevented. PMID:22081235

  18. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test...

  19. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test...

  20. 40 CFR Table B-4 to Subpart B of... - Line Voltage and Room Temperature Test Conditions

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Conditions B Table B-4 to Subpart B of Part 53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Testing Performance Characteristics of Automated Methods for SO2, CO, O3, and NO2 Pt. 53, Subpt. B, Table B-4 Table B-4 to Subpart B of Part 53—Line Voltage and Room Temperature Test Conditions Test...

  1. MULTI - TRACER CONTROL ROOM AIR INLEAKAGE PROTOCOL AND SIMULATED PRIMARY AND EXTENDED MULTI - ZONE RESULTS.

    SciTech Connect

    DIETZ,R.N.

    2002-01-01

    The perfluorocarbon tracer (PFT) technology can be applied simultaneously to the wide range in zonal flowrates (from tens of cfms in some Control Rooms to almost 1,000,000 cfm in Turbine Buildings), to achieve the necessary uniform tagging for subsequent determination of the desired air inleakage and outleakage from all zones surrounding a plant's Control Room (CR). New types of PFT sources (Mega sources) were devised and tested to handle the unusually large flowrates in a number of HVAC zones in power stations. A review of the plans of a particular nuclear power plant and subsequent simulations of the tagging and sampling results confirm that the technology can provide the necessary concentration measurement data to allow the important ventilation pathways involving the Control Room and its air flow communications with all adjacent zones to be quantitatively determined with minimal uncertainty. Depending on need, a simple single or 3-zone scheme (involving the Control Room alone or along with the Aux. Bldg. and Turbine Bldg.) or a more complex test involving up to 7 zones simultaneously can be accommodated with the current revisions to the technology; to test all the possible flow pathways, several different combinations of up to 7 zones would need to be run. The potential exists that for an appropriate investment, in about 2 years, it would be possible to completely evaluate an entire power plant in a single extended multizone test with up to 12 to 13 separate HVAC zones. With multiple samplers in the Control Room near each of the contiguous zones, not only will the prevalent inleakage or outleakage zones be documented, but the particular location of the pathway's room of ingress can be identified. The suggested protocol is to perform a 3-zone test involving the Control Room, Aux. Bldg., and Turbine Bldg. to (1) verify CR total inleakage and (2) proportion that inleakage to distinguish that from the other 2 major buildings and any remaining untagged locations

  2. Heating, ventilation and air conditioning systems

    SciTech Connect

    Kyle, D.M.; Sullivan, R.A.

    1993-02-01

    A study is made of several outstanding issues concerning the commercial development of environmental control systems for electric vehicles (EVs). Engineering design constraints such as federal regulations and consumer requirements are first identified. Next, heating and cooling loads in a sample automobile are calculated using a computer model available from the literature. The heating and cooling loads are then used as a basis for estimating the electrical consumption that is to be expected for heat pumps installed in EVs. The heat pump performance is evaluated using an automobile heat pump computer model which has been developed recently at Oak Ridge National Laboratory (ORNL). The heat pump design used as input to the model consists of typical finned-tube heat exchangers and a hermetic compressor driven by a variable-speed brushless dc motor. The simulations suggest that to attain reasonable system efficiencies, the interior heat exchangers that are currently installed as automobile air conditioning will need to be enlarged. Regarding the thermal envelope of the automobile itself, calculations are made which show that considerable energy savings will result if steps are taken to reduce {open_quote}hot soak{close_quote} temperatures and if the outdoor air ventilation rate is well controlled. When these changes are made, heating and cooling should consume less than 10% of the total stored electrical energy for steady driving in most U.S. climates. However, this result depends strongly upon the type of driving: The fraction of total power for heating and cooling ({open_quote}range penalty{close_quote}) increases sharply for driving scenarios having low average propulsion power, such as stop-and-go driving.

  3. Indoor Chemical Exposures: Humans' Non-respiratory Interactions with Room Air

    SciTech Connect

    Charles Weschler

    2010-03-29

    March 18, 2010 Berkeley Lab Environmental Energy Technology Division distinguished lecture: The marked difference in pollutant concentrations between an occupied and un-occupied room are only partially explained by human bio-effluents. Humans alter levels of ozone and related oxidants such as nitrate and hydroxyl radicals in the rooms they inhabit; in effect, they change the oxidative capacity of room air. Ozone-initiated reactions on exposed skin, hair and clothing generate products, including potentially irritating chemicals whose concentrations are much higher in the occupant's breathing zone than in the core of the room. Charles J. Weschler is a Professor at the School of Public Health, the Department of Environmental and Occupational Medicine and the Environmental and Occupational Health Sciences Institute (EOHSI) at the University of Medicine and Dentistry of New Jersey (UMDNJ)/Robert Wood Johnson Medical School & Rutgers University (New Jersey). He is also a Visiting Professor at the International Centre for Indoor Environment and Energy, Technical University of Denmark (DTU, Lyngby, Denmark).

  4. Indoor Chemical Exposures: Humans' Non-respiratory Interactions with Room Air

    ScienceCinema

    Charles Weschler

    2010-09-01

    March 18, 2010 Berkeley Lab Environmental Energy Technology Division distinguished lecture: The marked difference in pollutant concentrations between an occupied and un-occupied room are only partially explained by human bio-effluents. Humans alter levels of ozone and related oxidants such as nitrate and hydroxyl radicals in the rooms they inhabit; in effect, they change the oxidative capacity of room air. Ozone-initiated reactions on exposed skin, hair and clothing generate products, including potentially irritating chemicals whose concentrations are much higher in the occupant's breathing zone than in the core of the room. Charles J. Weschler is a Professor at the School of Public Health, the Department of Environmental and Occupational Medicine and the Environmental and Occupational Health Sciences Institute (EOHSI) at the University of Medicine and Dentistry of New Jersey (UMDNJ)/Robert Wood Johnson Medical School & Rutgers University (New Jersey). He is also a Visiting Professor at the International Centre for Indoor Environment and Energy, Technical University of Denmark (DTU, Lyngby, Denmark).

  5. Forced-air warming: a source of airborne contamination in the operating room?

    PubMed Central

    Albrecht, Mark; Gauthier, Robert; Leaper, David

    2009-01-01

    Forced-air-warming (FAW) is an effective and widely used means for maintaining surgical normothermia, but FAW also has the potential to generate and mobilize airborne contamination in the operating room. We measured the emission of viable and non-viable forms of airborne contamination from an arbitrary selection of FAW blowers (n=25) in the operating room. A laser particle counter measured particulate concentrations of the air near the intake filter and in the distal hose airstream. Filtration efficiency was calculated as the reduction in particulate concentration in the distal hose airstream relative to that of the intake. Microbial colonization of the FAW blower's internal hose surfaces was assessed by culturing the microorganisms recovered through swabbing (n=17) and rinsing (n=9) techniques. Particle counting revealed that 24% of FAW blowers were emitting significant levels of internally generated airborne contamination in the 0.5 to 5.0 µm size range, evidenced by a steep decrease in FAW blower filtration efficiency for particles 0.5 to 5.0 µm in size. The particle size-range-specific reduction in efficiency could not be explained by the filtration properties of the intake filter. Instead, the reduction was found to be caused by size-range-specific particle generation within the FAW blowers. Microorganisms were detected on the internal air path surfaces of 94% of FAW blowers. The design of FAW blowers was found to be questionable for preventing the build-up of internal contamination and the emission of airborne contamination into the operating room. Although we did not evaluate the link between FAW and surgical site infection rates, a significant percentage of FAW blowers with positive microbial cultures were emitting internally generated airborne contamination within the size range of free floating bacteria and fungi (<4 µm) that could, conceivably, settle onto the surgical site. PMID:21808690

  6. The Mycobiota of Air Inside and Outside the Meju Fermentation Room and the Origin of Meju Fungi.

    PubMed

    Kim, Dae-Ho; Kim, Sun-Hwa; Kwon, Soon-Wo; Lee, Jong-Kyu; Hong, Seung-Beom

    2015-09-01

    The fungi on Meju are known to play an important role as degrader of macromolecule of soybeans. In order to elucidate the origin of fungi on traditional Meju, mycobiota of the air both inside and outside traditional Meju fermentation rooms was examined. From 11 samples of air collected from inside and outside of 7 Meju fermentation rooms, 37 genera and 90 species of fungi were identified. In outside air of the fermentation room, Cladosporium sp. and Cladosporium cladosporioides were the dominant species, followed by Cladosporium tenuissimum, Eurotium sp., Phoma sp., Sistotrema brinkmannii, Alternaria sp., Aspergillus fumigatus, Schizophyllum commune, and Penicillium glabrum. In inside air of the fermentation room, Cladosporium sp., Aspergillus oryzae, Penicillium chrysogenum, Asp. nidulans, Aspergillus sp., Cla. cladosporioides, Eurotium sp., Penicillium sp., Cla. tenuissimum, Asp. niger, Eur. herbariorum, Asp. sydowii, and Eur. repens were collected with high frequency. The concentrations of the genera Aspergillus, Eurotium, and Penicillium were significantly higher in inside air than outside air. From this result and those of previous reports, the origin of fungi present on Meju was inferred. Of the dominant fungal species present on Meju, Lichtheimia ramosa, Mucor circinelloides, Mucor racemosus, and Scopulariopsis brevicaulis are thought to be originated from outside air, because these species are not or are rarely isolated from rice straw and soybean; however, they were detected outside air of fermentation room and are species commonly found in indoor environments. However, Asp. oryzae, Pen. polonicum, Eur. repens, Pen. solitum, and Eur. chevalieri, which are frequently found on Meju, are common in rice straw and could be transferred from rice straw to Meju. The fungi grow and produce abundant spores during Meju fermentation, and after the spores accumulate in the air of fermentation room, they could influence mycobiota of Meju fermentation in the following

  7. Air Conditioner Charging. Automotive Mechanics. Air Conditioning. Instructor's Guide [and] Student Guide.

    ERIC Educational Resources Information Center

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automobile air conditioning, consists of a student guide and an instructor guide dealing with air conditioning charging. Covered in the module are checking the air conditioning system for leaks, checking and adding refrigerant oil as needed, evacuating the system,…

  8. Refrigeration and Air-Conditioning Technology Workshop

    NASA Astrophysics Data System (ADS)

    Lewis, P. J.; Counce, D. M.

    1993-12-01

    The Alternative Fluorocarbon Environmental Acceptability Study (AFEAS), a consortium of fluorocarbon manufacturers, and the U.S. Department of Energy (DOE) are collaborating on a project to evaluate the energy use and global warming impacts of CFC alternatives. The goal of this project is to identify technologies that could replace the use of CFC's in refrigeration, heating, and air-conditioning equipment; to evaluate the direct impacts of chemical emissions on global warming; and to compile accurate estimates of energy use and indirect CO2 emissions of substitute technologies. The first phase of this work focused on alternatives that could be commercialized before the year 2000. The second phase of the project is examining not-in-kind and next-generation technologies that could be developed to replace CFC's, HCFC's, and HFC's over a longer period. As part of this effort, Oak Ridge National Laboratory held a workshop on June 23-25, 1993. The preliminary agenda covered a broad range of alternative technologies and at least one speaker was invited to make a brief presentation at the workshop on each technology. Some of the invited speakers were unable to participate, and in a few cases other experts could not be identified. As a result, those technologies were not represented at the workshop. Each speaker was asked to prepare a five to seven page paper addressing six key issues concerning the technology he/she is developing. These points are listed in the sidebar. Each expert also spoke for 20 to 25 minutes at the workshop and answered questions from the other participants concerning the presentation and area of expertise. The primary goal of the presentations and discussions was to identify the developmental state of the technology and to obtain comparable data on system efficiencies.

  9. On boundary conditions for the diffusion equation in room-acoustic prediction: Theory, simulations, and experiments.

    PubMed

    Jing, Yun; Xiang, Ning

    2008-01-01

    This paper proposes a modified boundary condition to improve the room-acoustic prediction accuracy of a diffusion equation model. Previous boundary conditions for the diffusion equation model have certain limitations which restrict its application to a certain number of room types. The boundary condition employing the Sabine absorption coefficient [V. Valeau et al., J. Acoust. Soc. Am. 119, 1504-1513 (2006)] cannot predict the sound field well when the absorption coefficient is high, while the boundary condition employing the Eyring absorption coefficient [Y. Jing and N. Xiang, J. Acoust. Soc. Am. 121, 3284-3287 (2007); A. Billon et al., Appl. Acoust. 69, (2008)] has a singularity whenever any surface material has an absorption coefficient of 1.0. The modified boundary condition is derived based on an analogy between sound propagation and light propagation. Simulated and experimental data are compared to verify the modified boundary condition in terms of room-acoustic parameter prediction. The results of this comparison suggest that the modified boundary condition is valid for a range of absorption coefficient values and successfully eliminates the singularity problem. PMID:18177146

  10. [Calibration of a room air gas monitor with certified reference gases].

    PubMed

    Krueger, W A; Trick, M; Schroeder, T H; Unertl, K E

    2003-12-01

    Photo-acoustic infrared spectrometry is considered to be the gold standard for on-line measurement of anesthetic waste gas in room air. For maintenance of the precision of the measurements, the manufacturer recommends calibration of the gas monitor monitor every 3-12 months. We investigated whether the use of reference gases with analysis certificate could serve as a feasible alternative to commercial recalibration. We connected a multi-gas monitor type1302 (Bruel & Kjaer, Naerum, Denmark) to compressed air bottles containing reference gases with analysis certificate. Using a T-piece with a flow-meter, we avoided the entry of room air during the calibration phase. Highly purified nitrogen was used for zero calibration. The reference concentrations for desflurane, enflurane, halothane, isoflurane, and sevoflurane ranged from 41.6-51.1 ml/m(3) (ppm) in synthetic air. Since there is an overlap of the infrared absorption spectra of volatile anesthetics with alcohol used in operating rooms, we performed a cross-compensation with iso-propanol (107.0 ppm). A two-point calibration was performed for N(2)O (96.2 and 979.0 ppm), followed by cross-compensation with CO(2). Nafion tubes were used in order to avoid erroneous measurements due to molecular relaxation phenomena. The deviation of the measurement values ranged initially from 0-2.0% and increased to up to 4.9% after 18 months. For N(2)O, the corresponding values were 4.2% and 2.7%, respectively. Thus, our calibration procedure using certified reference gases yielded precise measurements with low deterioration over 18 months. It seems to be advantageous that the precision can be determined whenever deemed necessary. This allows for an individual decision, when the gas monitor needs to be calibrated again. The costs for reference gases and working time as well as logistic aspects such as storage and expiration dates must be individually balanced against the costs for commercial recalibration. PMID:14691626

  11. Possible Economies in Air-Conditioning by Accepting Temperature Swings.

    ERIC Educational Resources Information Center

    Loudon, A. G.; Petherbridge, P.

    Public building air conditioning systems, which use constant and varying heat and cooling loads, are compared and investigated. Experiments indicated that constant temperature controls based on outside air temperature alone were inefficient. Ventilating a building with outside air and the methods of doing so are cited as being the most economical…

  12. Use of Recirculating Ventilation with Dust Filtration to Improve Wintertime Air Quality in a Swine Farrowing Room

    PubMed Central

    Anthony, T. Renée; Altmaier, Ralph; Jones, Samuel; Gassman, Rich; Park, Jae Hong; Peters, Thomas M.

    2016-01-01

    The performance of a recirculating ventilation system with dust filtration was evaluated to determine its effectiveness to improve the air quality in a swine farrowing room of a concentrated animal feeding operation (CAFO). Air was exhausted from the room (0.47 m3sec−1; 1000 cfm), treated with a filtration unit (Shaker-Dust Collector), and returned to the farrowing room to reduce dust concentrations while retaining heat necessary for livestock health. The air quality in the room was assessed over a winter, during which time limited fresh air is traditionally brought into the building. Over the study period, dust concentrations ranged from 0.005 to 0.31 mg m−3 (respirable) and 0.17 to 2.09 mg m−3 (inhalable). In-room dust concentrations were reduced (41% for respirable and 33% for inhalable) with the system in operation, while gas concentrations (ammonia [NH3], hydrogen sulfide [H2S], carbon monoxide [CO], carbon dioxide [CO2]) were unchanged. The position of the exhaust and return air systems provided reasonably uniform contaminant distributions, although the respirable dust concentrations nearest one of the exhaust ducts was statistically higher than other locations in the room, with differences averaging only 0.05 mg m−3. Throughout the study, CO2 concentrations consistently exceeded 1540 ppm (industry recommendations) and on eight of the 18 study days it exceeded 2500 ppm (50% of the ACGIH TLV), with significantly higher concentrations near a door to a temperature-controlled hallway that was typically often left open. Alternative heaters are recommended to reduce CO2 concentrations in the room. Contaminant concentrations were modeled using production and environmental factors, with NH3 related to the number of sow in the room and outdoor temperatures and CO2 related to the number of piglets and outdoor temperatures. The recirculating ventilation system provided dust reduction without increasing concentrations of hazardous gases. PMID:25950713

  13. Use of Recirculating Ventilation With Dust Filtration to Improve Wintertime Air Quality in a Swine Farrowing Room.

    PubMed

    Anthony, T Renée; Altmaier, Ralph; Jones, Samuel; Gassman, Rich; Park, Jae Hong; Peters, Thomas M

    2015-01-01

    The performance of a recirculating ventilation system with dust filtration was evaluated to determine its effectiveness to improve the air quality in a swine farrowing room of a concentrated animal feeding operation (CAFO). Air was exhausted from the room (0.47 m(3) sec(-1); 1000 cfm), treated with a filtration unit (Shaker-Dust Collector), and returned to the farrowing room to reduce dust concentrations while retaining heat necessary for livestock health. The air quality in the room was assessed over a winter, during which time limited fresh air is traditionally brought into the building. Over the study period, dust concentrations ranged from 0.005-0.31 mg m(-3) (respirable) and 0.17-2.09 mg m(-3) (inhalable). In-room dust concentrations were reduced (41% for respirable and 33% for inhalable) with the system in operation, while gas concentrations (ammonia [NH3], hydrogen sulfide [H2S], carbon monoxide [CO], carbon dioxide [CO2]) were unchanged. The position of the exhaust and return air systems provided reasonably uniform contaminant distributions, although the respirable dust concentrations nearest one of the exhaust ducts was statistically higher than other locations in the room, with differences averaging only 0.05 mg m(-3). Throughout the study, CO2 concentrations consistently exceeded 1540 ppm (industry recommendations) and on eight of the 18 study days it exceeded 2500 ppm (50% of the ACGIH TLV), with significantly higher concentrations near a door to a temperature-controlled hallway that was typically often left open. Alternative heaters are recommended to reduce CO2 concentrations in the room. Contaminant concentrations were modeled using production and environmental factors, with NH3 related to the number of sow in the room and outdoor temperatures and CO2 related to the number of piglets and outdoor temperatures. The recirculating ventilation system provided dust reduction without increasing concentrations of hazardous gases. PMID:25950713

  14. Repair Air Conditioning, COC Bldg 2605, Basement Plan. By Strategic ...

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

    Repair Air Conditioning, COC Bldg 2605, Basement Plan. By Strategic Air Command, Civil Engineering. Drawing no. R-156, sheet no. 1 of 4, 15 August 1968; project no. MAR-125-8;CE-572; file drawer 2605-5. Last revised 31 August 1968?. Scale one-eighth inch and one-quarter inch to one foot. 29x41 inches. pencil on paper - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  15. Repair Air Conditioning, COC Bldg 2605, First Floor Plan. By ...

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

    Repair Air Conditioning, COC Bldg 2605, First Floor Plan. By Strategic Air Command, Civil Engineering. Drawing no. R-156, sheet no. 2 of 4, 15 August 1968; project no. MAR-125-8;CE-572; file drawer 2605-6. Scale one-eighth inch to one foot. 29x41 inches. pencil on paper 405 - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  16. Solar-powered air-conditioning

    NASA Technical Reports Server (NTRS)

    Clark, D. C.; Rousseau, J.

    1977-01-01

    Report focuses on recent study on development of solar-powered residential air conditioners and is based on selected literature through 1975. Its purposes are to characterize thermal and mechanical systems that might be useful in development of Rankine-cycle approach to solar cooling and assessment of a Lithium Bromide/Water absorption cycle system.

  17. The Influence of Meteorological Conditions on Air Pollution

    ERIC Educational Resources Information Center

    Campbell, N. A.; Gipps, J.

    1975-01-01

    Explains the distribution of air pollutants as related to such meteorological conditions as temperature inversions, ground inversion, and wind velocity. Uses a power station to illustrate the effect of some of the meteorological conditions mentioned. (GS)

  18. Thermal Environment for Classrooms. Central System Approach to Air Conditioning.

    ERIC Educational Resources Information Center

    Triechler, Walter W.

    This speech compares the air conditioning requirements of high-rise office buildings with those of large centralized school complexes. A description of one particular air conditioning system provides information about the system's arrangement, functions, performance efficiency, and cost effectiveness. (MLF)

  19. Heating, Ventilation, and Air Conditioning Series. Duty Task List.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This task list is intended for use in planning and/or evaluating a competency-based course in heating, ventilation, and air conditioning. The guide outlines the tasks entailed in eight different duties typically required of employees in the following occupations: residential installer, domestic refrigeration technician, air conditioning and…

  20. Air Conditioning and Refrigeration Program Articulation, 1981-1982.

    ERIC Educational Resources Information Center

    Dallas County Community Coll. District, TX.

    Based on a survey of high school programs and courses in the Dallas County Community College District (DCCCD), this articulated program is designed to prepare students for entry-level employment in the air conditioning and refrigeration industry, including residential and commercial air conditioning and commercial refrigeration. The skills and…

  1. Mountain Plains Learning Experience Guide: Heating, Refrigeration, & Air Conditioning.

    ERIC Educational Resources Information Center

    Carey, John

    This Heating, Refrigeration, and Air Conditioning course is comprised of eleven individualized units: (1) Refrigeration Tools, Materials, and Refrigerant; (2) Basic Heating and Air Conditioning; (3) Sealed System Repairs; (4) Basic Refrigeration Systems; (5) Compression Systems and Compressors; (6) Refrigeration Controls; (7) Electric Circuit…

  2. Residential Heat and Air Conditioning. Florida Vocational Program Guide.

    ERIC Educational Resources Information Center

    University of South Florida, Tampa. Dept. of Adult and Vocational Education.

    The program guide for residential heat and air conditioning courses in Florida identifies primary considerations for the organization, operation, and evaluation of a vocational education program. Following an occupational description for the job title for air-conditioning installer-servicer, window unit, and its Dictionary of Occupational Titles…

  3. BEETIT: Building Cooling and Air Conditioning

    SciTech Connect

    2010-09-01

    BEETIT Project: The 14 projects that comprise ARPA-E’s BEETIT Project, short for “Building Energy Efficiency Through Innovative Thermodevices,” are developing new approaches and technologies for building cooling equipment and air conditioners. These projects aim to drastically improve building energy efficiency and reduce greenhouse gas emissions such as carbon dioxide (CO2) at a cost comparable to current technologies.

  4. Air pollution and emergency room admissions for chronic obstructive pulmonary disease: A 5-year study

    SciTech Connect

    Sunyer, J.; Saez, M.; Murillo, C.; Castellsague, J.; Martinez, F.; Anto, J.M. )

    1993-04-01

    An association between sulfur dioxide levels in urban air and the daily number of emergency room admissions for chronic obstructive pulmonary disease was previously reported in Barcelona, Spain, for the period 1985-1986. The present study assesses this association over a longer period of time, 1985-1989. This made it possible to carry out separate analyses for the winter and summer seasons and thus to control more adequately for weather and influenza epidemics. An increase of 25 micrograms/m3 in sulfur dioxide (24-hour average) produced adjusted changes of 6% and 9% in emergency room admissions for chronic obstructive pulmonary disease during winter and summer, respectively. For black smoke, a similar change was found during winter, although the change was smaller in summer. The association of each pollutant with chronic obstructive pulmonary disease admissions remained significant after control for the other pollutant. The present findings support the conclusion that current levels of sulfur dioxide and black smoke may have an effect on the respiratory health of susceptible persons.

  5. Air conditioning system with supplemental ice storing and cooling capacity

    DOEpatents

    Weng, Kuo-Lianq; Weng, Kuo-Liang

    1998-01-01

    The present air conditioning system with ice storing and cooling capacity can generate and store ice in its pipe assembly or in an ice storage tank particularly equipped for the system, depending on the type of the air conditioning system. The system is characterized in particular in that ice can be produced and stored in the air conditioning system whereby the time of supplying cooled air can be effectively extended with the merit that the operation cycle of the on and off of the compressor can be prolonged, extending the operation lifespan of the compressor in one aspect. In another aspect, ice production and storage in great amount can be performed in an off-peak period of the electrical power consumption and the stored ice can be utilized in the peak period of the power consumption so as to provide supplemental cooling capacity for the compressor of the air conditioning system whereby the shift of peak and off-peak power consumption can be effected with ease. The present air conditioning system can lower the installation expense for an ice-storing air conditioning system and can also be applied to an old conventional air conditioning system.

  6. Tribological reactions of perfluoroalkyl polyether oils with stainless steel under ultrahigh vacuum conditions at room temperature

    NASA Technical Reports Server (NTRS)

    Mori, Shigeyuki; Morales, Wilfredo

    1989-01-01

    The reaction between three types of commercial perfluoroalkyl polyether (PFPE) oils and stainless steel 440C was investigated experimentally during sliding under ultrahigh vacuum conditions at room temperature. It is found that the tribological reaction of PFPE is mainly affected by the activity of the mechanically formed fresh surfaces of metals rather than the heat generated at the sliding contacts. The fluorides formed on the wear track act as a boundary layer, reducing the friction coefficient.

  7. Air-conditioning in the human nasal cavity.

    PubMed

    Elad, David; Wolf, Michael; Keck, Tilman

    2008-11-30

    Healthy humans normally breathe through their nose even though its complex geometry imposes a significantly higher resistance in comparison with mouth breathing. The major functional roles of nasal breathing are defense against infiltrating particles and conditioning of the inspired air to nearly alveolar conditions in order to maintain the internal milieu of the lung. The state-of-the-art of the existing knowledge on nasal air-conditioning will be discussed in this review, including in vivo measurements in humans and computational studies on nasal air-conditioning capacity. Areas where further studies will improve our understanding and may help medical diagnosis and intervention in pathological states will be introduced. PMID:18565805

  8. Experimental investigation on performance of ice storage air-conditioning system with separate heat pipe

    SciTech Connect

    Fang, Guiyin; Liu, Xu; Wu, Shuangmao

    2009-11-15

    An experimental study on operation performance of ice storage air-conditioning system with separate helical heat pipe is conducted in this paper. The experimental system of ice storage air-conditioning system with separate heat pipe is set up. The performance parameters such as the evaporation pressure and the condensation pressure of refrigeration system, the refrigeration capacity and the COP (coefficient of performance) of the system, the IPF (ice packing factor) and the cool storage capacity in the cool storage tank during charging period, and the cool discharge rate and the cool discharge capacity in the cool storage tank, the outlet water temperature in the cool storage tank and the outlet air temperature in room unit during discharging period are investigated. The experimental results show that the ice storage air-conditioning system with separate helical heat pipe can stably work during charging and discharging period. This indicates that the ice storage air-conditioning system with separate helical heat pipe is well adapted to cool storage air-conditioning systems in building. (author)

  9. Technology Solutions Case Study: Overcoming Comfort Issues Due to Reduced Flow Room Air Mixing

    SciTech Connect

    2015-03-01

    Energy efficiency upgrades reduce heating and cooling loads on a house. With enough load reduction and if the HVAC system warrants replacement, the HVAC system is often upgraded with a more efficient, lower capacity system that meets the loads of the upgraded house. In this project, IBACOS studied when HVAC equipment is downsized and ducts are unaltered to determine conditions that could cause a supply air delivery problem and to evaluate the feasibility of modifying the duct systems using minimally invasive strategies to improve air distribution.

  10. Tuneable polaritonics at room temperature with strongly coupled Tamm plasmon polaritons in metal/air-gap microcavities

    NASA Astrophysics Data System (ADS)

    Grossmann, C.; Coulson, C.; Christmann, G.; Farrer, I.; Beere, H. E.; Ritchie, D. A.; Baumberg, J. J.

    2011-06-01

    We report strong coupling between Tamm plasmons and excitons in III-V quantum wells at room temperature in ultracompact sample designs. A high refractive index contrast air-gap mirror together with optical Tamm states at a metal/semiconductor interface tightly confines the intracavity field leading to substantial local field enhancements. Angular-resolved reflectivity spectra give clear evidence for anticrossing in the dispersion relation. Room temperature Rabi splittings of 10 meV are found in excellent agreement with simulations. Electrical control of the polariton modes is realized without need for doped mirror layers. Such air-gap microcavities open innovative possibilites for electrically tunable microcavities and polaritonic microelectromechanics.

  11. Air pollution and hospital emergency room admissions for chronic obstructive pulmonary disease in Valencia, Spain.

    PubMed

    Tenías, José Maria; Ballester, Ferran; Pérez-Hoyos, Santiago; Rivera, María Luisa

    2002-01-01

    The short-term relationship between levels of air pollution and emergency room admissions for chronic obstructive pulmonary disease was assessed in Valencia, Spain. The design was an ecological time-series study in which daily variation in air pollution was related to emergency chronic obstructive pulmonary disease visits to one of the city's hospitals. The pollutants under investigation were Black Smoke, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone. The degree of association was analyzed with Poisson autoregressive regression, for which trend, seasonal patterns, temperature, humidity, days of the week, and incidence of influenza were controlled. Increases of 10 microg/m3 in ozone levels (lag 5) and of 1 mg/m3 in carbon monoxide (lag 1) were associated with increases of 6.1% (95% confidence interval [CI] = 2.2%, 10.1%) and of 3.9% (95% CI = 1.4%, 6.6%), respectively, in the expected chronic obstructive pulmonary disease cases. There was no significant association for the remainder of the pollutants. The described effects persisted even when the authors used models of differing specifications and when generalized additive models were used. The authors concluded that the results of this investigation, together with results of earlier research, demonstrate the significant effect of pollution on various health indicaors within Valencia. PMID:12071359

  12. Diethylene glycol mono butyl ether concentrations in room air from application of cleaner formulations to hard surfaces.

    PubMed

    Gibson, W B; Keller, P R; Foltz, D J; Harvey, G J

    1991-07-01

    Diethylene glycol monobutyl ether (DGBE) is a solvent used in some liquid hard surface cleaners. We evaluated the inhalation component of consumer exposure in the home to DGBE from the use of cleaning products containing up to 9% DGBE. Several experiments were conducted with restricted room air flow, exaggerated amounts of cleaning solutions, and no rinsing in order to develop an exposure scenario that would exceed exposures likely encountered by consumers. DGBE vapors in the air were monitored by collection on charcoal tubes, followed by desorption and quantitation by gas chromatography. Air was collected from the centre of the room and from the breathing zone of the person doing the washing task. Room air concentrations of DGBE showed peak values between one and three hours after task initiation; DGBE concentrations then gradually decreased with time. Peak concentrations did not exceed 1.6 ppmv. The total DGBE in the air at the time of maximum air concentrations accounted for only 1 to 3% of the DGBE on the washed surfaces. The person doing the washing task was exposed to average DGBE concentrations in the breathing zone below 0.8 ppmv in all experiments. The methods described for measuring DGBE concentrations in air are generally applicable to other solvents and easily adaptable to various experimental situations. PMID:1824325

  13. Phase transformation of lithium tungsten bronzes, Li {sub x}WO{sub 3}, at room temperature ambient conditions

    SciTech Connect

    Dey, K.R.; Ruescher, C.H. . E-mail: C.ruescher@mineralogie.uni-hannover.de; Gesing, Th.M.; Hussain, A.

    2007-04-12

    Samples of Li {sub x}WO{sub 3} with x = 0.05-0.7 were synthesized at 700 deg. C for 7 days using appropriate amounts of Li{sub 2}WO{sub 4}, WO{sub 3} and WO{sub 2} in evacuated sealed silica tubes. The products reveal different phases of perovskite tungsten bronze (PTB). An interesting phenomenon observed for the PTB phases is the gradual change in colours when they are exposed at room temperature ambient conditions (in air). This effect has been investigated using X-ray powder diffraction, infrared absorption and optical reflectivity methods for the powdered samples before and after 30 and 90 days in air. The spectra of the samples with x = 0.25-0.5 are dominated by a peak with maximum around 16,000 cm{sup -1} in the Kubelka Munk spectra which is related to the cubic Li {sub x}WO{sub 3} phase. The peak intensity increases with increasing x. After 30 days of exposure in air this peak disappeared for x < 0.5 samples due to a diffusion of Li from Li {sub x}WO{sub 3}. X-ray and IR data show a gradual transformation into the lower symmetric phases (PTB{sub cubic} {sup {yields}} PTB{sub tetragonal} {sup {yields}} PTB{sub orthorhombic} {sup {yields}} PTB{sub monoclinic}). The results suggest that Li is attracted by O{sub 2} to the surface forming Li{sub 2}O which further reacts with H{sub 2}O and CO{sub 2} in air. The in air altered samples regain their original colour when reheated at 500 deg. C in vacuum.

  14. Desiccant Enhanced Evaporative Air Conditioning: Parametric Analysis and Design; Preprint

    SciTech Connect

    Woods, J.; Kozubal, E.

    2012-10-01

    This paper presents a parametric analysis using a numerical model of a new concept in desiccant and evaporative air conditioning. The concept consists of two stages: a liquid desiccant dehumidifier and a dew-point evaporative cooler. Each stage consists of stacked air channel pairs separated by a plastic sheet. In the first stage, a liquid desiccant film removes moisture from the process (supply-side) air through a membrane. An evaporatively-cooled exhaust airstream on the other side of the plastic sheet cools the desiccant. The second-stage indirect evaporative cooler sensibly cools the dried process air. We analyze the tradeoff between device size and energy efficiency. This tradeoff depends strongly on process air channel thicknesses, the ratio of first-stage to second-stage area, and the second-stage exhaust air flow rate. A sensitivity analysis reiterates the importance of the process air boundary layers and suggests a need for increasing airside heat and mass transfer enhancements.

  15. Techno-Economic Analysis of Indian Draft Standard Levels for RoomAir Conditioners

    SciTech Connect

    McNeil, Michael A.; Iyer, Maithili

    2007-03-01

    The Indian Bureau of Energy Efficiency (BEE) finalized its first set of efficiency standards and labels for room air conditioners in July of 2006. These regulations followed soon after the publication of levels for frost-free refrigerators in the same year. As in the case of refrigerators, the air conditioner program introduces Minimum Efficiency Performance Standards (MEPS) and comparative labels simultaneously, with levels for one to five stars. Also like the refrigerator program, BEE defined several successive program phases of increasing stringency. In support of BEE's refrigerator program, Lawrence Berkeley National Laboratory (LBNL) produced an analysis of national impacts of standards in collaboration with the Collaborative Labeling and Standards Program (CLASP). That analysis drew on LBNL's experience with standards programs in the United States, as well as many other countries. Subsequently, as part of the process for setting optimal levels for air conditioner regulations, CLASP commissioned LBNL to provide support to BEE in the form of a techno-economic evaluation of air conditioner efficiency technologies. This report describes the methodology and results of this techno-economic evaluation. The analysis consists of three components: (1) Cost effectiveness to consumers of efficiency technologies relative to current baseline. (2) Impacts on the current market from efficiency regulations. (3) National energy and financial impacts. The analysis relied on detailed and up-to-date technical data made available by BEE and industry representatives. Technical parameters were used in conjunction with knowledge about air conditioner use patterns in the residential and commercial sectors, and prevailing marginal electricity prices, in order to give an estimate of per-unit financial impacts. In addition, the overall impact of the program was evaluated by combining unit savings with market forecasts in order to yield national impacts. LBNL presented preliminary results

  16. High pressure air jet in the endoscopic preparation room: risk of noise exposure on occupational health.

    PubMed

    Chiu, King-Wah; Lu, Lung-Sheng; Wu, Cheng-Kun

    2015-01-01

    After high-level disinfection of gastrointestinal endoscopes, they are hung to dry in order to prevent residual water droplets impact on patient health. To allow for quick drying and clinical reuse, some endoscopic units use a high pressure air jet (HPAJ) to remove the water droplets on the endoscopes. The purpose of this study was to evaluate the excessive noise exposure with the use of HPAJ in endoscopic preparation room and to investigate the risk to occupational health. Noise assessment was taken during 7 automatic endoscopic reprocessors (AERs) and combined with/without HPAJ use over an 8-hour time-weighted average (TWA). Analytical procedures of the NIOSH and the ISO for noise-induced hearing loss were estimated to develop analytic models. The peak of the noise spectrum of combined HPAJ and 7 AERs was significantly higher than that of the 7 AERs alone (108.3 ± 1.36 versus 69.3 ± 3.93 dBA, P < 0.0001). The risk of hearing loss (HL > 2.5 dB) was 2.15% at 90 dBA, 11.6% at 95 dBA, and 51.3% at 100 dBA. The odds ratio was 49.1 (95% CI: 11.9 to 203.6). The noise generated by the HPAJ to work over TWA seriously affected the occupational health and safety of those working in an endoscopic preparation room. PMID:25710009

  17. Association of allergic asthma emergency room visits with the main biological and chemical air pollutants.

    PubMed

    Makra, László; Matyasovszky, István; Bálint, Beatrix

    2012-08-15

    Joint effect of biological (pollen) and chemical air pollutants on asthma emergency room (ER) visits was analyzed for Szeged region of Southern Hungary. Our database of a nine-year period (1999-2007) includes daily number of asthma emergency room (ER) visits, and daily mean concentrations of CO, PM(10), NO, NO(2), O(3) and SO(2), furthermore two pollen variables (Ambrosia and total pollen excluding Ambrosia), as well. The analysis was performed for ER visits of asthma bronchiale using two age groups (adults and the elderly) of males and females for three seasons. Factor analysis was performed in order to clarify the relative importance of the pollutant variables affecting asthma ER visits. Asthma ER visits denote notably stronger associations with the pollutants in adult male than in adult female patients both for the pollen season of Ambrosia and the pollen-free season. Furthermore, adults are substantially more sensitive to severe asthma attack than the elderly for the season of total pollen excluding Ambrosia pollen. The joint effect of the chemical and pollen variables is the highest for the asthma ER cases in the pollen season of Ambrosia, basically due to the extra impact of the total pollen excluding Ambrosia pollen and partly due to Ambrosia pollen. A nonparametric regression technique was applied to discriminate between events of ER visit-no ER visit using pollen and chemical pollutants as explaining variables. Based on multiple correlations, the strongest relationships between ER visits and pollutants are observed during the pollen-free season. The elderly group with asthma bronchiale is characterized by weaker relationships between ER visits and pollutants compared to adults. Ratio of the number of correct decisions on the events of ER visit-no ER visit is lowest for the season of total pollen excluding Ambrosia pollen. Otherwise, similar conclusions hold as those received by multiple correlations. PMID:22750174

  18. Extreme conditions in a dissolving air nanobubble

    NASA Astrophysics Data System (ADS)

    Yasui, Kyuichi; Tuziuti, Toru; Kanematsu, Wataru

    2016-07-01

    Numerical simulations of the dissolution of an air nanobubble in water have been performed taking into account the effect of bubble dynamics (inertia of the surrounding liquid). The presence of stable bulk nanobubbles is not assumed in the present study because the bubble radius inevitably passes the nanoscale in the complete dissolution of a bubble. The bubble surface is assumed to be clean because attachment of hydrophobic materials on the bubble surface could considerably change the gas diffusion rate. The speed of the bubble collapse (the bubble wall speed) increases to about 90 m/s or less. The shape of a bubble is kept nearly spherical because the amplitude of the nonspherical component of the bubble shape is negligible compared to the instantaneous bubble radius. In other words, a bubble never disintegrates into daughter bubbles during the dissolution. At the final moment of the dissolution, the temperature inside a bubble increases to about 3000 K due to the quasiadiabatic compression. The bubble temperature is higher than 1000 K only for the final 19 ps. However, the Knudsen number is more than 0.2 for this moment, and the error associated with the continuum model should be considerable. In the final 2.3 ns, only nitrogen molecules are present inside a bubble as the solubility of nitrogen is the lowest among the gas species. The radical formation inside a bubble is negligible because the probability of nitrogen dissociation is only on the order of 10-15. The pressure inside a bubble, as well as the liquid pressure at the bubble wall, increases to about 5 GPa at the final moment of dissolution. The pressure is higher than 1 GPa for the final 0.7 ns inside a bubble and for the final 0.6 ns in the liquid at the bubble wall. The liquid temperature at the bubble wall increases to about 360 K from 293 K at the final stage of the complete dissolution.

  19. Extreme conditions in a dissolving air nanobubble.

    PubMed

    Yasui, Kyuichi; Tuziuti, Toru; Kanematsu, Wataru

    2016-07-01

    Numerical simulations of the dissolution of an air nanobubble in water have been performed taking into account the effect of bubble dynamics (inertia of the surrounding liquid). The presence of stable bulk nanobubbles is not assumed in the present study because the bubble radius inevitably passes the nanoscale in the complete dissolution of a bubble. The bubble surface is assumed to be clean because attachment of hydrophobic materials on the bubble surface could considerably change the gas diffusion rate. The speed of the bubble collapse (the bubble wall speed) increases to about 90 m/s or less. The shape of a bubble is kept nearly spherical because the amplitude of the nonspherical component of the bubble shape is negligible compared to the instantaneous bubble radius. In other words, a bubble never disintegrates into daughter bubbles during the dissolution. At the final moment of the dissolution, the temperature inside a bubble increases to about 3000 K due to the quasiadiabatic compression. The bubble temperature is higher than 1000 K only for the final 19 ps. However, the Knudsen number is more than 0.2 for this moment, and the error associated with the continuum model should be considerable. In the final 2.3 ns, only nitrogen molecules are present inside a bubble as the solubility of nitrogen is the lowest among the gas species. The radical formation inside a bubble is negligible because the probability of nitrogen dissociation is only on the order of 10^{-15}. The pressure inside a bubble, as well as the liquid pressure at the bubble wall, increases to about 5 GPa at the final moment of dissolution. The pressure is higher than 1 GPa for the final 0.7 ns inside a bubble and for the final 0.6 ns in the liquid at the bubble wall. The liquid temperature at the bubble wall increases to about 360 K from 293 K at the final stage of the complete dissolution. PMID:27575216

  20. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. F Appendix F to Subpart B of Part 430—Uniform...

  1. Copper-catalyzed N-arylation of amines with part-per-million catalyst loadings under air at room temperature.

    PubMed

    Xie, Ruilong; Fu, Hua; Ling, Yun

    2011-08-21

    An efficient copper-catalyzed method for N-arylation of amines has been developed with part-per-million catalyst loadings at room temperature under air. Reactions of substituted (E)-1-(2-halophenyl)alkanone oximes with aliphatic amines or aromatic amines provided the N-arylation products in good to excellent yields. PMID:21727962

  2. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. F Appendix F to Subpart B of Part 430—Uniform...

  3. Application of solar energy to air conditioning systems

    NASA Technical Reports Server (NTRS)

    Nash, J. M.; Harstad, A. J.

    1976-01-01

    The results of a survey of solar energy system applications of air conditioning are summarized. Techniques discussed are both solar powered (absorption cycle and the heat engine/Rankine cycle) and solar related (heat pump). Brief descriptions of the physical implications of various air conditioning techniques, discussions of status, proposed technological improvements, methods of utilization and simulation models are presented, along with an extensive bibliography of related literature.

  4. Isolation and Characterization of Bacteria Capable of Tolerating the Extreme Conditions of Clean Room Environments▿

    PubMed Central

    La Duc, Myron T.; Dekas, Anne; Osman, Shariff; Moissl, Christine; Newcombe, David; Venkateswaran, Kasthuri

    2007-01-01

    In assessing the bacterial populations present in spacecraft assembly, spacecraft test, and launch preparation facilities, extremophilic bacteria (requiring severe conditions for growth) and extremotolerant bacteria (tolerant to extreme conditions) were isolated. Several cultivation approaches were employed to select for and identify bacteria that not only survive the nutrient-limiting conditions of clean room environments but can also withstand even more inhospitable environmental stresses. Due to their proximity to spacefaring objects, these bacteria pose a considerable risk for forward contamination of extraterrestrial sites. Samples collected from four geographically distinct National Aeronautics and Space Administration clean rooms were challenged with UV-C irradiation, 5% hydrogen peroxide, heat shock, pH extremes (pH 3.0 and 11.0), temperature extremes (4°C to 65°C), and hypersalinity (25% NaCl) prior to and/or during cultivation as a means of selecting for extremotolerant bacteria. Culture-independent approaches were employed to measure viable microbial (ATP-based) and total bacterial (quantitative PCR-based) burdens. Intracellular ATP concentrations suggested a viable microbial presence ranging from below detection limits to 106 cells/m2. However, only 0.1 to 55% of these viable cells were able to grow on defined culture medium. Isolated members of the Bacillaceae family were more physiologically diverse than those reported in previous studies, including thermophiles (Geobacillus), obligate anaerobes (Paenibacillus), and halotolerant, alkalophilic species (Oceanobacillus and Exiguobacterium). Non-spore-forming microbes (α- and β-proteobacteria and actinobacteria) exhibiting tolerance to the selected stresses were also encountered. The multiassay cultivation approach employed herein enhances the current understanding of the physiological diversity of bacteria housed in these clean rooms and leads us to ponder the origin and means of translocation of

  5. Isolation and characterization of bacteria capable of tolerating the extreme conditions of clean room environments.

    PubMed

    La Duc, Myron T; Dekas, Anne; Osman, Shariff; Moissl, Christine; Newcombe, David; Venkateswaran, Kasthuri

    2007-04-01

    In assessing the bacterial populations present in spacecraft assembly, spacecraft test, and launch preparation facilities, extremophilic bacteria (requiring severe conditions for growth) and extremotolerant bacteria (tolerant to extreme conditions) were isolated. Several cultivation approaches were employed to select for and identify bacteria that not only survive the nutrient-limiting conditions of clean room environments but can also withstand even more inhospitable environmental stresses. Due to their proximity to spacefaring objects, these bacteria pose a considerable risk for forward contamination of extraterrestrial sites. Samples collected from four geographically distinct National Aeronautics and Space Administration clean rooms were challenged with UV-C irradiation, 5% hydrogen peroxide, heat shock, pH extremes (pH 3.0 and 11.0), temperature extremes (4 degrees C to 65 degrees C), and hypersalinity (25% NaCl) prior to and/or during cultivation as a means of selecting for extremotolerant bacteria. Culture-independent approaches were employed to measure viable microbial (ATP-based) and total bacterial (quantitative PCR-based) burdens. Intracellular ATP concentrations suggested a viable microbial presence ranging from below detection limits to 10(6) cells/m(2). However, only 0.1 to 55% of these viable cells were able to grow on defined culture medium. Isolated members of the Bacillaceae family were more physiologically diverse than those reported in previous studies, including thermophiles (Geobacillus), obligate anaerobes (Paenibacillus), and halotolerant, alkalophilic species (Oceanobacillus and Exiguobacterium). Non-spore-forming microbes (alpha- and beta-proteobacteria and actinobacteria) exhibiting tolerance to the selected stresses were also encountered. The multiassay cultivation approach employed herein enhances the current understanding of the physiological diversity of bacteria housed in these clean rooms and leads us to ponder the origin and means

  6. Anaerobic digestion in mesophilic and room temperature conditions: Digestion performance and soil-borne pathogen survival.

    PubMed

    Chen, Le; Jian, Shanshan; Bi, Jinhua; Li, Yunlong; Chang, Zhizhou; He, Jian; Ye, Xiaomei

    2016-05-01

    Tomato plant waste (TPW) was used as the feedstock of a batch anaerobic reactor to evaluate the effect of anaerobic digestion on Ralstonia solanacearum and Phytophthora capsici survival. Batch experiments were carried out for TS (total solid) concentrations of 2%, 4% and 6% respectively, at mesophilic (37±1°C) and room (20-25°C) temperatures. Results showed that higher digestion performance was achieved under mesophilic digestion temperature and lower TS concentration conditions. The biogas production ranged from 71 to 416L/kg VS (volatile solids). The inactivation of anaerobic digestion tended to increase as digestion performance improved. The maximum log copies reduction of R. solanacearum and P. capsici detected by quantitative PCR (polymerase chain reaction) were 3.80 and 4.08 respectively in reactors with 4% TS concentration at mesophilic temperatures. However, both in mesophilic and room temperature conditions, the lowest reduction of R. solanacearum was found in the reactors with 6% TS concentration, which possessed the highest VFA (volatile fatty acid) concentration. These findings indicated that simple accumulation of VFAs failed to restrain R. solanacearum effectively, although the VFAs were considered poisonous. P. capsici was nearly completely dead under all conditions. Based on the digestion performance and the pathogen survival rate, a model was established to evaluate the digestate biosafety. PMID:27155428

  7. Greenhouse gas emissions for refrigerant choices in room air conditioner units.

    PubMed

    Galka, Michael D; Lownsbury, James M; Blowers, Paul

    2012-12-01

    In this work, potential replacement refrigerants for window-mounted room air conditioners (RACs) in the U.S. have been evaluated using a greenhouse gas (GHG) emissions analysis. CO(2)-equivalent emissions for several hydrofluoroethers (HFEs) and other potential replacements were compared to the most widely used refrigerants today. Included in this comparison are pure refrigerants that make up a number of hydrofluorocarbon (HFC) mixtures, pure hydrocarbons, and historically used refrigerants such as propane and ammonia. GHG emissions from direct and indirect sources were considered in this thermodynamic analysis. Propylene, dimethyl ether, ammonia, R-152a, propane, and HFE-152a all performed effectively in a 1 ton window unit and produced slightly lower emissions than the currently used R-22 and R-134a. The results suggest that regulation of HFCs in this application would have some effect on reducing emissions since end-of-life emissions remain at 55% of total refrigerant charge despite EPA regulations that mandate 80% recovery. Even so, offsite emissions due to energy generation dominate over direct GHG emissions and all the refrigerants perform similarly in totals of indirect GHG emissions. PMID:23136858

  8. Circularly Polarized Persistent Room-Temperature Phosphorescence from Metal-Free Chiral Aromatics in Air.

    PubMed

    Hirata, Shuzo; Vacha, Martin

    2016-04-21

    Circularly polarized room-temperature phosphorescence (RTP) with persistent emission characteristics was observed from metal-free chiral binaphthyl structures. Enantiomers of the binaphthyl compounds doped into an amorphous hydroxylated steroid matrix produced blue fluorescence and yellow persistent RTP in air. The lifetime and quantum yield of the yellow persistent RTP were 0.67 s and 2.3%, respectively. The dissymmetry factors of circular dichroism (CD) in the first absorption band, circularly polarized fluorescence (CPF), and circularly polarized persistent RTP were |1.1 × 10(-3)|, |4.5 × 10(-4)|, and |2.3 × 10(-3)|, respectively. A comparison between the experimental data and calculations by time-dependent density functional theory for transient CD spectra confirmed that the binaphthyl conformations in the lowest singlet excited state (S1) and the lowest triplet state (T1) were different. The large difference in the dissymmetry factors for the CPF and the circularly polarized persistent RTP was likely caused by this conformational change between S1 and T1. PMID:27058743

  9. Association between weather conditions and the number of patients at the emergency room in an Argentine hospital

    NASA Astrophysics Data System (ADS)

    Rusticucci, Matilde; Bettolli, Laura M.; de los Angeles Harris, M.

    2002-02-01

    The aim of this paper is to study the relationships between hospital emergencies and weather conditions by analysing summer and winter cases of patients requiring attention at the emergency room of a hospital in the city of Buenos Aires, Argentina. Hospital data have been sorted into seven different diagnostic groups as follows: (1) respiratory, cardiovascular and chest-pain complaints; (2) digestive, genitourinary and abdominal complaints; (3) neurological and psychopathological disorders; (4) infections; (5) contusion and crushing, bone and muscle complaints; (6) skin and allergies and (7) miscellaneous complaints. In general, there is an increase of 16.7% in winter while, for group 2 and group 6, there are more patients in summer, 54% and 75% respectively. In summer, the total number of patients for group 6 shows a significant positive correlation with temperature and dew-point temperature, and a negative correlation with the sea-level pressure for the same day. In winter, the same relationship exists, however its correlation is not as strong. The lags observed between these three variables: maximum dew-point temperature, maximum temperature, minimum air pressure and the peaks in admissions are 1, 2 and 4 days respectively. In winter, increases in temperature and dew point and decreases in pressure are followed by a peak in admissions for group 2. In winter, there are significantly more cases in group 5 on warm, dry days and on warm, wet days in the summer.

  10. The microbiological quality of air improves when using air conditioning systems in cars

    PubMed Central

    2010-01-01

    Background Because of better comfort, air conditioning systems are a common feature in automobiles these days. However, its impact on the number of particles and microorganisms inside the vehicle - and by this its impact on the risk of an allergic reaction - is yet unknown. Methods Over a time period of 30 months, the quality of air was investigated in three different types of cars (VW Passat, VW Polo FSI, Seat Alhambra) that were all equipped with a automatic air conditioning system. Operation modes using fresh air from outside the car as well as circulating air from inside the car were examined. The total number of microorganisms and the number of mold spores were measured by impaction in a high flow air sampler. Particles of 0.5 to 5.0 μm diameter were counted by a laser particle counter device. Results Overall 32 occasions of sampling were performed. The concentration of microorganisms outside the cars was always higher than it was inside the cars. Few minutes after starting the air conditioning system the total number of microorganisms was reduced by 81.7%, the number of mold spores was reduced by 83.3%, and the number of particles was reduced by 87.8%. There were no significant differences neither between the types of cars nor between the types of operation mode of the air conditioning system (fresh air vs. circulating air). All parameters that were looked for in this study improved during utilization of the car's air conditioning system. Conclusions We believe that the risk of an allergic reaction will be reduced during use also. Nevertheless, we recommend regular maintenance of the system and replacement of older filters after defined changing intervals. PMID:20515449

  11. Pioneer developments in self-contained air conditioning

    SciTech Connect

    Steinfeld, H.K.

    1986-01-01

    This is a story covering a chapter in the air conditioning industry when that industry was young. It had created the science through the inventions of Dr. Carrier and had developed the art of large systems to a high degree. But prior to 1930, only big jobs were installed, in all of which the air was pre-conditioned by sprays of water. Air conditioning solely for the benefit of the ordinary citizen was not available, and the progress of developing small equipment was lacking. It was only with the invention of ''Freon 12'' in 1930 by Thomas Midgley that all pieces seemed to fall into place for the design of self-contained units. Large companies and small entrepreneurs were ready to enter the field and combine newly developed components like hermetic compressors, improved electrical equipment, capacitors, etc., and lightweight finned coils.

  12. Non-CFC air conditioning for transit buses

    SciTech Connect

    Pesaran, A.A.; Parent, Y.O.; Bharathan, D.

    1992-11-01

    In the United Sates, more than 80% of transit city buses are air conditioned. Vapor compression refrigeration systems are standard for air conditioning buses and account for up to 25% of fuel consumption in the cooling season. Vapor compression devices use chlorofluorocarbons (CFCs), chemicals that contributes to Earths`s ozone depletion and to global warming. Currently, evaporative cooling is an economical alternative to CFC vapor compression refrigeration for air conditioning buses. It does not use CFCs but is restricted in use to arid climates. This limitation can be eliminated by dehumidifying the supply air using desiccants. We studied desiccant systems for cooling transit buses and found that the use of a desiccant-assisted evaporative cooling system is feasible and can deliver the required cooling. The weight and the size of the desiccant system though larger than vapor compression systems, can be easily accommodated within a bus. Fuel consumption for naming desiccant systems was about 70% less than CFC refrigeration system, resulting in payback periods of less than 2.5 years under most circumstances. This preliminary study indicated that desiccant systems combined with evaporative cooling is a CFC-free option to vapor compression refrigeration for air conditioning of transit buses. The concept is ready to be tested in a fun prototype scale in a commercial bus.

  13. Non-CFC air conditioning for transit buses

    SciTech Connect

    Pesaran, A.A.; Parent, Y.O.; Bharathan, D.

    1992-11-01

    In the United Sates, more than 80% of transit city buses are air conditioned. Vapor compression refrigeration systems are standard for air conditioning buses and account for up to 25% of fuel consumption in the cooling season. Vapor compression devices use chlorofluorocarbons (CFCs), chemicals that contributes to Earths's ozone depletion and to global warming. Currently, evaporative cooling is an economical alternative to CFC vapor compression refrigeration for air conditioning buses. It does not use CFCs but is restricted in use to arid climates. This limitation can be eliminated by dehumidifying the supply air using desiccants. We studied desiccant systems for cooling transit buses and found that the use of a desiccant-assisted evaporative cooling system is feasible and can deliver the required cooling. The weight and the size of the desiccant system though larger than vapor compression systems, can be easily accommodated within a bus. Fuel consumption for naming desiccant systems was about 70% less than CFC refrigeration system, resulting in payback periods of less than 2.5 years under most circumstances. This preliminary study indicated that desiccant systems combined with evaporative cooling is a CFC-free option to vapor compression refrigeration for air conditioning of transit buses. The concept is ready to be tested in a fun prototype scale in a commercial bus.

  14. Using listening difficulty ratings of conditions for speech communication in rooms

    NASA Astrophysics Data System (ADS)

    Sato, Hiroshi; Bradley, John S.; Morimoto, Masayuki

    2005-03-01

    The use of listening difficulty ratings of speech communication in rooms is explored because, in common situations, word recognition scores do not discriminate well among conditions that are near to acceptable. In particular, the benefits of early reflections of speech sounds on listening difficulty were investigated and compared to the known benefits to word intelligibility scores. Listening tests were used to assess word intelligibility and perceived listening difficulty of speech in simulated sound fields. The experiments were conducted in three types of sound fields with constant levels of ambient noise: only direct sound, direct sound with early reflections, and direct sound with early reflections and reverberation. The results demonstrate that (1) listening difficulty can better discriminate among these conditions than can word recognition scores; (2) added early reflections increase the effective signal-to-noise ratio equivalent to the added energy in the conditions without reverberation; (3) the benefit of early reflections on difficulty scores is greater than expected from the simple increase in early arriving speech energy with reverberation; (4) word intelligibility tests are most appropriate for conditions with signal-to-noise (S/N) ratios less than 0 dBA, and where S/N is between 0 and 15-dBA S/N, listening difficulty is a more appropriate evaluation tool. .

  15. Trend of Refrigeration and Air-Conditioning Technology in Korea

    NASA Astrophysics Data System (ADS)

    Oh, Hoo-Kyu; Papk, Ki-Won

    It can be said that refrigeration and air-conditioning technology in Korea dates back to the ancient dynasty, all the way up to the Sokkuram(700s) and Seokbinggo(1700s), But modern refrigeration and air-conditioning technology was first developed in and introduced to Korea in the1960swith the modernization of Korea, Today it is at a level which meets that of advanced countries in both the industrial and domestic fields. As of 2003, there were about 700 companies that owned cold storage/freezing/refrigeration facilities, with cold storage capacity of about 2,000, 000tons and capacity per company of about 3,000 tons. These facilities most are continuously expanding and automating their facilities. 62 million units of refrigeration and air-conditioning machinery and equipment were produced in 2003, worth a total of 7.7 trillion won(about 7.7 thousand million US). On the academic side there are 9 universities and 12 junior colleges with courses in either refrigeration and air-conditioning or architectural equipment. Academic societies such as the Society of Air-conditioning and Refrigerating Engineers of Korea(SAREK), and industrial societies like the Korean Association of Refrigeration(KAR) are active members of the refrigeration and air-conditioning industry. The1eare also national/government-established research institutions such as the Korea Institute of Science and Technology(KIST), the Korea Institute of Machinery and Materials (KIMM), the Korea Institute of Energy Research(KIER), and the Korea Institute of Industrial Technology (KITECH).

  16. Effects of the air pressure on the wave-packet dynamics of gaseous iodine molecules at room temperature

    NASA Astrophysics Data System (ADS)

    Fan, Rongwei; He, Ping; Chen, Deying; Xia, Yuanqin; Yu, Xin; Wang, Jialing; Jiang, Yugang

    2013-02-01

    Based on ultrafast laser pulses, time-resolved resonance enhancement coherent anti-Stokes Raman scattering (RE-CARS) is applied to investigate wave-packet dynamics in gaseous iodine. The effects of air pressure on the wave-packet dynamics of iodine molecules are studied at pressures ranging from 1.5 Torr to 750 Torr. The RE-CARS signals are recorded in a gas cell filled with a mixture of about 0.3 Torr iodine in air buffer gas at room temperature. The revivals and fractional revival structures in the wave-packet signal are found to gradually disappear with rising air pressure up to 750 Torr, and the decay behaviors of the excited B-state and ground X-state become faster with increasing air pressure, which is due to the collision effects of the molecules and the growing complexity of the spectra at high pressures.

  17. Winter weather conditions vs. air quality in Tricity, Poland

    NASA Astrophysics Data System (ADS)

    Nidzgorska-Lencewicz, Jadwiga; Czarnecka, Małgorzata

    2015-02-01

    The principal aim of this paper is to assess the influence of meteorological conditions on the variability of sulfur dioxide and PM10 particulate matter concentration of pollutants during winter with consideration of an excess of admissible standards. The basis for the analysis were hourly concentrations of PM10 and sulfur dioxide as well as the basic meteorological elements automatically recorded at five stations located in the Tricity agglomeration, and operating within the weather station network belonging to the Agency of Regional Air Quality Monitoring in the Gdańsk Metropolitan Area (ARMAAG). The analysis covers the calendar winters (December-February) in the years 2004/2005 through 2009/2010. The variability of the concentrations of both pollutants under certain weather conditions, i.e. air temperature and relative humidity, atmospheric pressure, as well as wind speed and direction, were evaluated by means of cluster analysis using k-means belonging to a group of non-hierarchical cluster analysis method. The composite effect of meteorological conditions on the variability of sulfur dioxide and PM10 concentrations in isolated clusters were determined by multiple linear regression, using a stepwise procedure, at the significance level α = 0.05 and α = 0.01. The effect of individual weather elements on the pattern of concentration levels was determined using partial regression coefficients. Clusters grouping the highest concentrations of pollutants were characterised, in most cases, by the lowest air temperature and a lower wind speed, and often a higher pressure, and sometimes slightly lower relative air humidity, i.e. the conditions of anticyclonic weather. Weather conditions had a statistically significant effect on the concentrations of both pollutants in all clusters; however, air temperature and wind speed had the crucial role. Thermal conditions were the decisive factor in the winter season 2005/2006 with the most frequent, overnormative daily

  18. Effect of Room Ventilation Rates in Rodent Rooms with Direct-Exhaust IVC Systems.

    PubMed

    Geertsema, Roger S; Lindsell, Claire E

    2015-09-01

    When IVC are directly exhausted from a rodent housing room, the air quality of the room can become independent of the intracage air quality and may reduce the need for high room ventilation rates. This study assessed the effect of decreasing the ventilation rate in rodent rooms using direct-exhaust IVC systems. The study was conducted over 16 wk and compared conditions in 8 rodent rooms that had ventilation rates of 5 to 6 air changes per hour (ACH) with those in rooms at 10 to 12 ACH. At the low ventilation rate, rooms had higher CO₂ concentrations, higher dew point temperature, and lower particulate levels and spent a greater percentage of time above the temperature set point than did rooms at the high rate. The levels of allergens and endotoxins in room air were the same regardless of the ventilation rate. Differences seen in parameters within cages at the 2 ventilation rates were operationally irrelevant. We detected no total volatile organic compounds in the room that were attributable to ammonia, regardless of the ventilation rate. Clearing the air of ethanol after a spill took longer at the low compared with high rate. However, ethanol clearance was faster at the low rate when the demand-control system was activated than at the high ventilation rate alone. Air quality in the room and in the cages were acceptable with room ventilation rates of 5 to 6 ACH in rodent rooms that use direct-exhaust IVC systems. PMID:26424250

  19. Effect of Room Ventilation Rates in Rodent Rooms with Direct-Exhaust IVC Systems

    PubMed Central

    Geertsema, Roger S; Lindsell, Claire E

    2015-01-01

    When IVC are directly exhausted from a rodent housing room, the air quality of the room can become independent of the intracage air quality and may reduce the need for high room ventilation rates. This study assessed the effect of decreasing the ventilation rate in rodent rooms using direct-exhaust IVC systems. The study was conducted over 16 wk and compared conditions in 8 rodent rooms that had ventilation rates of 5 to 6 air changes per hour (ACH) with those in rooms at 10 to 12 ACH. At the low ventilation rate, rooms had higher CO2 concentrations, higher dew point temperature, and lower particulate levels and spent a greater percentage of time above the temperature set point than did rooms at the high rate. The levels of allergens and endotoxins in room air were the same regardless of the ventilation rate. Differences seen in parameters within cages at the 2 ventilation rates were operationally irrelevant. We detected no total volatile organic compounds in the room that were attributable to ammonia, regardless of the ventilation rate. Clearing the air of ethanol after a spill took longer at the low compared with high rate. However, ethanol clearance was faster at the low rate when the demand-control system was activated than at the high ventilation rate alone. Air quality in the room and in the cages were acceptable with room ventilation rates of 5 to 6 ACH in rodent rooms that use direct-exhaust IVC systems. PMID:26424250

  20. Technology Equipment Rooms.

    ERIC Educational Resources Information Center

    Day, C. William

    2001-01-01

    Examines telecommunications equipment room design features that allow for growth and can accommodate numerous equipment replacements and upgrades with minimal service disruption and with minimal cost. Considerations involving the central hub, power and lighting needs, air conditioning, and fire protection are discussed. (GR)

  1. Study of long term options for electric vehicle air conditioning

    SciTech Connect

    Dieckmann, J.; Mallory, D. , Inc., Cambridge, MA )

    1991-07-01

    There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an [open quotes]upsized[close quotes] condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.

  2. Study of long term options for electric vehicle air conditioning

    SciTech Connect

    Dieckmann, J.; Mallory, D.

    1991-07-01

    There are strong incentives in terms of national energy and environmental policy to encourage the commercialization of electrically powered vehicles in the U.S. Among these incentives are reduced petroleum consumption, improved electric generation capacity utilization, reduced IC engine emissions, and, depending on the primary fuel used for electric power generation, reduced emissions of carbon dioxide. A basic requirement for successfully commercializing any motor vehicle in the US is provision of adequate passenger comfort heating and air conditioning (cooling). Although air conditioning is generally sold as optional equipment, in excess of 80% of the automobiles and small trucks sold in the US have air conditioning systems. In current, pre-commercial electric vehicles, comfort heating is provided by a liquid fuel fired heater that heats water which is circulated through the standard heater core in the conventional interior air handling unit. Air conditioning is provided by electric motor driven compressors, installed in a system having, perhaps, an {open_quotes}upsized{close_quotes} condenser and a standard evaporator (front and rear evaporators in some instances) installed in the conventional interior air handler. Although this approach is adequate in the near term for initial commercialization efforts, a number of shortcomings of this arrangement, as well as longer range concerns need to be addressed. In this project, the long term alternatives for cooling and heating electric vehicles effectively, efficiently (with minimum range penalties), and without adverse environmental impacts have been examined. Identification of options that can provide both heating and cooling is important, in view of the disadvantages of carrying separate heating and cooling systems in the vehicle.

  3. State Skill Standards: Heating, Ventilation, Air Conditioning, and Refrigeration

    ERIC Educational Resources Information Center

    Ball, Larry; Soukup, Dennis

    2006-01-01

    The Department of Education has undertaken an ambitious effort to develop statewide career and technical education skill standards. The standards in this document are for Heating, Ventilation, Air Conditioning and Refrigeration (HVAC&R) programs and are designed to clearly state what the student should know and be able to do upon completion of an…

  4. Advanced Print Reading. Heating, Ventilation and Air Conditioning.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    This is a workbook for students learning advanced blueprint reading for heating, ventilation, and air conditioning applications. The workbook contains eight units covering the following material: architectural working drawings; architectural symbols and dimensions; basic architectural electrical symbols; wiring symbols; basic piping symbols;…

  5. Air Conditioning, Heating, and Refrigeration. Competency-Based Curriculum Manual.

    ERIC Educational Resources Information Center

    Gourley, Frank A., Jr.

    This manual was developed to serve as an aid to administrators and instructors involved with postsecondary air conditioning, heating, and refrigeration programs. The first of six chapters contains general information on program implementation, the curriculum design, facilities and equipment requirements, and textbooks and references. Chapter 2…

  6. Heating, Air-Conditioning, and Refrigeration Technician. National Skill Standards.

    ERIC Educational Resources Information Center

    Vocational Technical Education Consortium of States, Decatur, GA.

    This guide contains information on the knowledge and skills identified by industry as essential to the job performance of heating, air-conditioning, and refrigeration technicians. It is intended to assist training providers in public and private institutions, as well as in industry, to develop and implement training that will provide workers with…

  7. An Analysis of the Air Conditioning, Refrigerating and Heating Occupation.

    ERIC Educational Resources Information Center

    Frass, Melvin R.; Krause, Marvin

    The general purpose of the occupational analysis is to provide workable, basic information dealing with the many and varied duties performed in the air conditioning, refrigerating, and heating occupation. The document opens with a brief introduction followed by a job description. The bulk of the document is presented in table form. Six duties are…

  8. Air Conditioning, Heating, and Refrigeration: Scope and Sequence.

    ERIC Educational Resources Information Center

    Nashville - Davidson County Metropolitan Public Schools, TN.

    This scope and sequence guide, developed for an air conditioning, heating, and refrigeration vocational education program, represents an initial step in the development of a systemwide articulated curriculum sequence for all vocational programs within the Metropolitan Nashville Public School System. It was developed as a result of needs expressed…

  9. Heating and Air Conditioning Specialist. Teacher Edition. Automotive Service Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This instructor's guide contains materials for teaching the heating and air conditioning specialist component of a competency-based instructional program for students preparing for employment in the automotive service trade. It is based on the National Institute of Automotive Service Excellence task lists. The six instructional units presented…

  10. Heating, Ventilating, and Air Conditioning. Energy Technology Series.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    This course in heating, ventilating, and air conditioning is one of 16 courses in the Energy Technology Series developed for an Energy Conservation-and-Use Technology curriculum. Intended for use in two-year postsecondary technical institutions to prepare technicians for employment, the courses are also useful in industry for updating employees in…

  11. Careers for the 70's in Heating and Air Conditioning

    ERIC Educational Resources Information Center

    Toner, James P.

    1974-01-01

    In a trade encompassing all others in construction, installation foremen for heating/air conditioning firms spend a varied day (repairing a water heater, overseeing installation crews). Decision-makers who must think while using their hands, they rely heavily on preparation in math, mechanical drawing, blueprint reading, physics, and electicity.…

  12. Modelling and simulation of air-conditioning cycles

    NASA Astrophysics Data System (ADS)

    Rais, Sandi; Kadono, Yoshinori; Murayama, Katsunori; Minakuchi, Kazuya; Takeuchi, Hisae; Hasegawa, Tatsuya

    2016-05-01

    The heat-pump cycle for air conditioning was investigated both numerically and experimentally by evaluating the coefficient of performance (COP) under Japanese Industrial Standard (JIS B 8619:1999) and ANSI/AHRI standard 750-2007 operating conditions. We used two expansion valve coefficients Cv_{(\\varphi )} = 0.12 for standard operating conditions (Case 1) approaching 1.3 MPa at high pressure and 0.2 MPa at low pressure, and Cv_{(\\varphi )} = 0.06 namely poor operating conditions (Case 2). To improve the performance of the air conditioner, we compared the performance for two outside air temperatures, 35 and 40 °C (Case 3). The simulation and experiment comparison resulted the decreasing of the COP for standard operating condition is equal to 14 %, from 3.47 to 2.95 and a decrease of the cooling capacity is equal to 18 %, from 309.72 to 253.53 W. This result was also occurred in poor operating condition which the COP was superior at 35 °C temperature.

  13. An Assessment of Indoor Air Quality before, during and after Unrestricted Use of E-Cigarettes in a Small Room

    PubMed Central

    O’Connell, Grant; Colard, Stéphane; Cahours, Xavier; Pritchard, John D.

    2015-01-01

    Airborne chemicals in the indoor environment arise from a wide variety of sources such as burning fuels and cooking, construction materials and furniture, environmental tobacco smoke as well as outdoor sources. To understand the contribution of exhaled e-cigarette aerosol to the pre-existing chemicals in the ambient air, an indoor air quality study was conducted to measure volatile organic compounds (including nicotine and low molecular weight carbonyls), polycyclic aromatic hydrocarbons, tobacco-specific nitrosamines and trace metal levels in the air before, during and after e-cigarette use in a typical small office meeting room. Measurements were compared with human Health Criteria Values, such as indoor air quality guidelines or workplace exposure limits where established, to provide a context for potential bystander exposures. In this study, the data suggest that any additional chemicals present in indoor air from the exhaled e-cigarette aerosol, are unlikely to present an air quality issue to bystanders at the levels measured when compared to the regulatory standards that are used for workplaces or general indoor air quality. PMID:25955526

  14. Efficacy of ultraviolet germicidal irradiation of upper-room air in inactivating airborne bacterial spores and mycobacteria in full-scale studies

    NASA Astrophysics Data System (ADS)

    Xu, Peng; Peccia, Jordan; Fabian, Patricia; Martyny, John W.; Fennelly, Kevin P.; Hernandez, Mark; Miller, Shelly L.

    The efficacy of ultraviolet germicidal irradiation (UVGI) for inactivating airborne bacterial spores and vegetative mycobacteria cells was evaluated under full-scale conditions. Airborne bacteria inactivation experiments were conducted in a test room (87 m 3), fitted with a modern UVGI system (216 W all lamps operating, average upper zone UV irradiance 42±19 μW cm -2) and maintained at 25°C and 50% relative humidity, at two ventilation rates (0 and 6 air changes per hour). Bacillus subtilis (spores), Mycobacterium parafortuitum, and Mycobacterium bovis BCG cells were aerosolized continuously into the room such that their numbers and physiologic state were comparable both with and without the UVGI and ventilation system operating. Air samples were collected using glass impingers (9 breathing-zone locations) and multi-stage impactors, and collected bacteria were quantified using direct microscopy and standard culturing assays. UVGI reduced the room-average concentration of culturable airborne bacteria between 46% and 80% for B. subtilis spores, between 83% and 98% for M. parafortuitum, and 96-97% for M. bovis BCG cells, depending on the ventilation rate. An additional set of experiments, in which M. parafortuitum was aerosolized into the test room and then allowed to decay under varying UVGI and ventilation rates, yielded an inactivation rate of 16±1.2 h -1 for the UVGI system, all lamps operating. The Z value (inactivation rate normalized to UVGI irradiance) was estimated to be 1.2±0.15×10 -3 cm 2 μW -1 s -1 for aerosolized M. parafortuitum at 50% relative humidity.

  15. Influence of indoor air quality (IAQ) objectives on air-conditioned offices in Hong Kong.

    PubMed

    Hui, Pui-Shan; Mui, Kwok-Wai; Wong, Ling-Tim

    2008-09-01

    It is costly to sample all air pollutants of a general community. Air sampling should be conducted based on a practical assessment strategy and monitoring plan. In Hong Kong, the Environmental Protection Department (HKEPD) launched an Indoor Air Quality (IAQ) certification scheme to grade workplace IAQ as 'Excellent' or 'Good' by measuring the levels of nine common indoor air pollutants, namely carbon dioxide (CO(2)), carbon monoxide (CO), respirable suspended particulates (RSP), nitrogen dioxide (NO(2)), ozone (O(3)), formaldehyde (HCHO), total volatile organic compounds (TVOC), radon (Rn), and airborne bacteria count (ABC). Although average office IAQ performance has been improved since the implementation of this certification scheme, there are still resource issues and technical difficulties. To streamline the assessment of office IAQ performance, this study proposes a simple index of IAQ benchmarks formulated in compliance with the HKEPD requirements. In particular, three of the nine listed common air pollutants were selected as the 'representatives' for the overall satisfactory IAQ. Together with the assessment results of 422 Hong Kong air-conditioned offices, the index was evaluated in terms of test sensitivity, specificity and predictive values. Proved to be feasible to describe the IAQ of some air-conditioned offices, this IAQ index would be a useful tool for policymakers, building owners and professionals to quantify IAQ performance in offices and to make decisions on resources and manpower management for efficient mitigation actions. PMID:17973197

  16. Prostaglandin release from isolated rabbit cerebral cortex micro-vessels--comparison of 6-keto PGF1 alpha and PGE2 release from micro-vessels incubated in 100% O2, room air and 95% N2:5% CO2.

    PubMed

    Rodrigues, A M; Gerritsen, M E

    1984-01-01

    Prostaglandin release from microvessels isolated from the rabbit cerebral cortex was determined under three different atmospheric conditions: 100% O2 ("O2") room air, and 95% N2:5% CO2 ("N2-CO2"). Initial studies with homogenates prepared from rabbit cerebral microvessels (RCMV) indicated two pathways of enzymatic PGH2 transformation, namely PGI2 synthase and GSH-dependent PGH-PGE isomerase. We measured the release of the principal products of these pathways, 6-keto PGF1 alpha and PGE2 from freshly prepared RCMV. The release of 6-keto PGF1 alpha exceeded that of PGE2 in all three protocols. RCMV incubated in "N2-CO2" exhibited a reduction in the release of 6-keto PGF1 alpha compared to room air or "O2" incubated RCMV, evident at 30-60 min of incubation. No significant differences in the release of PGE2 were observed among the three incubation protocols. In all three incubation protocols the ratio of 6-keto PGF1 alpha to PGE2 did not differ during the initial 10 minutes of each incubation. After 30 to 60 min of incubation, this ratio did not change from the "O2" or room air treated RCMV, but decreased significantly for the "N2-CO2" treated group. To determine the reversibility of the apparent "N2-CO2" induced decline in 6-keto PGF1 alpha release, microvessels were removed from the nitrogen atmosphere and incubated in room air. Release was measured during the initial 10 min following reintroduction to room air and was compared to room air pretreated controls treated in an identical manner.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6431653

  17. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    SciTech Connect

    Boeder, A; Zimm, C

    2006-09-30

    Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate

  18. Interaction of Failed Fuel Rods Under Air Ingress Conditions

    SciTech Connect

    Hozer, Zoltan; Windberg, Peter; Nagy, Imre; Maroti, Laszlo; Matus, Lajos; Horvath, Marta; Csordas, Anna Pinter; Balasko, Marton; Czitrovszky, Aladar; Jani, Peter

    2003-03-15

    In the late phase of a severe reactor accident, the molten corium interacts with the vessel wall, and it can lead to the failure of the lower head. Through the failed bottom wall, part of the corium can flow into the cavity, and air can enter the primary circuit. The residual fuel in the core periphery will be further oxidized in air atmosphere. The degradation process will accelerate, and new chemical species will be formed, which can have an impact on the release of radioactive materials.Two experiments were carried out with electrically heated nine-rod pressurized water reactor-type bundles in the CODEX (COre Degradation EXperiment) facility to provide experimental data on the behavior of real fuel bundles under air oxidation conditions. The main objective of the tests was the investigation of oxidation phenomena, and some other important aspects (e.g., enhanced fission product release) were not addressed.The CODEX air ingress tests indicated the acceleration of oxidation phenomena and core degradation processes during the late phase of the vessel melt through accident, when air can have access to the residual fuel bundles in the reactor core. The degradation process was accompanied with zirconium-nitride formation and release of uranium-rich aerosols.

  19. Do residential air-conditioning rebates miss the mark?

    SciTech Connect

    Stickney, B.; Shepard, M.

    1994-12-31

    The rebates utilities provide for residential central air conditioners and heat pumps to encourage improved cooling efficiency may inadvertently reward higher peak demand in many cases. This problem could be avoided by using both efficiency and peak performance to determine eligibility for rebates. Such changes to incentive formulas would better align the utilities` DSM programs with the dual goals of improved efficiency and peak demand reduction. Improved peak performance would be especially advantageous for sunbelt utilities whose residential cooling load is highly coincident with the summer peak. Air conditioning has been called the utilities` ``load from hell,`` because it is intermittent, unpredictable, and is the largest contributor to summer peak demand, requiring massive investments in power generation and delivery capacity. It is no wonder then that more DSM programs are targeted at space cooling than at any other end use. Ironically, however, all of the residential rebate programs the authors examined for central air conditioners and heat pumps are based on the seasonal energy efficiency ratio (SEER), which provides a valuable measure of seasonal energy efficiency but is not a good indicator of peak demand. Residential central air conditioning incentive programs for eight major utilities are based exclusively on SEER and most ratchet up the incentive levels with increasing SEER. None include the measure for peak demand for residential cooling equipment, which is the so-called energy efficiency ratio, or EER.

  20. The Effects of Workload and Working Conditions on Operating Room Nurses and Technicians.

    PubMed

    Uğurlu, Ziyafet; Karahan, Azize; Ünlü, Hayriye; Abbasoğlu, Aysel; Özhan Elbaş, Nalan; Avcı Işık, Sevcan; Tepe, Aylin

    2015-09-01

    This study was conducted between August 15 and September 20, 2013, to determine the effects of workload and working conditions on operating room (OR) nurses and technicians. The study sample included 74 OR nurses and technicians working in a private university's six hospitals. The Individual Workload Perception Scale and a questionnaire that collected data on risk and environmental factors were used. The mean age of study participants was 29.3 ± 6.7 years, and 62.2% of the participants were female. More than 90% of the nurses and technicians had experienced spills or splashing of blood or other body fluids; anesthetic gases and radiation had affected 63.5% and 71.6% of nurses and technicians, respectively; 63.5% reported lumbar pain; and 46.6% defined the work environment as very stressful. The average workload scale score was 32.4 ± 6.2 (min = 11, max = 55). OR nurses and technicians are exposed to many occupational risks. PMID:26206853

  1. Solar air conditioning with solid absorbents and earth cooling

    NASA Astrophysics Data System (ADS)

    Mayer, E.

    An experimental design is described for an efficient desiccant cooling system using natural cold sink to reduce the moisture content of the ambient air. Used in a warm, humid, tropical climate, the unit is shown to provide up to 0.77 ton of refrigeration under extreme conditions with an average daily coefficient of performance of 0.5. Solar heat is applied to regenerate the silica gel.

  2. [Simulation and air-conditioning in the nose].

    PubMed

    Keck, T; Lindemann, J

    2010-05-01

    Heating and humidification of the respiratory air are the main functions of the nasal airways in addition to cleansing and olfaction. Optimal nasal air conditioning is mandatory for an ideal pulmonary gas exchange in order to avoid dessication and adhesion of the alveolar capillary bed. The complex three-dimensional anatomical structure of the nose makes it impossible to perform detailed in vivo studies on intranasal heating and humidification within the entire nasal airways applying various technical set-ups. The main problem of in vivo temperature and humidity measurements is a poor spatial and time resolution. Therefore, in vivo measurements are feasible to a restricted extent, only providing single temperature values as the complete nose is not entirely accessible. Therefore, data on the overall performance of the nose are only based on one single measurement within each nasal segment. In vivo measurements within the entire nose are not feasible. These serious technical issues concerning in vivo measurements led to a large number of numerical simulation projects in the last few years providing novel information about the complex functions of the nasal airways. In general, numerical simulations only calculate predictions in a computational model, e. g. realistic nose model, depending on the setting of the boundary conditions. Therefore, numerical simulations achieve only approximations of a possible real situation. The aim of this report is the synopsis of the technical expertise on the field of in vivo nasal air conditioning, the novel information of numerical simulations and the current state of knowledge on the influence of nasal and sinus surgery on nasal air conditioning. PMID:20352565

  3. Solar air-conditioning-active, hybrid and passive

    SciTech Connect

    Yellott, J. I.

    1981-04-01

    After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)

  4. Room temperature freezing and orientational control of surface-immobilized peptides in air.

    PubMed

    Li, Yaoxin; Zhang, Xiaoxian; Myers, John; Abbott, Nicholas L; Chen, Zhan

    2015-07-14

    Sugar coatings can stabilize the "native" structure and control the orientation of surface-immobilized peptides in air, providing a potential approach to retain biological functions of surface-immobilized biomolecules in air. This method is general and applicable to complex enzymes. PMID:26068205

  5. High Technology Centrifugal Compressor for Commercial Air Conditioning Systems

    SciTech Connect

    Ruckes, John

    2006-04-15

    R&D Dynamics, Bloomfield, CT in partnership with the State of Connecticut has been developing a high technology, oil-free, energy-efficient centrifugal compressor called CENVA for commercial air conditioning systems under a program funded by the US Department of Energy. The CENVA compressor applies the foil bearing technology used in all modern aircraft, civil and military, air conditioning systems. The CENVA compressor will enhance the efficiency of water and air cooled chillers, packaged roof top units, and other air conditioning systems by providing an 18% reduction in energy consumption in the unit capacity range of 25 to 350 tons of refrigeration The technical approach for CENVA involved the design and development of a high-speed, oil-free foil gas bearing-supported two-stage centrifugal compressor, CENVA encompassed the following high technologies, which are not currently utilized in commercial air conditioning systems: Foil gas bearings operating in HFC-134a; Efficient centrifugal impellers and diffusers; High speed motors and drives; and System integration of above technologies. Extensive design, development and testing efforts were carried out. Significant accomplishments achieved under this program are: (1) A total of 26 builds and over 200 tests were successfully completed with successively improved designs; (2) Use of foil gas bearings in refrigerant R134a was successfully proven; (3) A high speed, high power permanent magnet motor was developed; (4) An encoder was used for signal feedback between motor and controller. Due to temperature limitations of the encoder, the compressor could not operate at higher speed and in turn at higher pressure. In order to alleviate this problem a unique sensorless controller was developed; (5) This controller has successfully been tested as stand alone; however, it has not yet been integrated and tested as a system; (6) The compressor successfully operated at water cooled condensing temperatures Due to temperature

  6. Increased cardiac output, not pulmonary artery systolic pressure, increases intrapulmonary shunt in healthy humans breathing room air and 40% O2

    PubMed Central

    Elliott, Jonathan E; Duke, Joseph W; Hawn, Jerold A; Halliwill, John R; Lovering, Andrew T

    2014-01-01

    Blood flow through intrapulmonary arteriovenous anastomoses (IPAVAs) has been demonstrated to increase in healthy humans during a variety of conditions; however, whether or not this blood flow represents a source of venous admixture (/) that impairs pulmonary gas exchange efficiency (i.e. increases the alveolar-to-arterial difference (A–aDO2)) remains controversial and unknown. We hypothesized that blood flow through IPAVAs does provide a source of /. To test this, blood flow through IPAVAs was increased in healthy humans at rest breathing room air and 40% O2: (1) during intravenous adrenaline (epinephrine) infusion at 320 ng kg−1 min−1 (320 ADR), and (2) with vagal blockade (2 mg atropine), before and during intravenous adrenaline infusion at 80 ng kg−1 min−1 (ATR + 80 ADR). When breathing room air the A–aDO2 increased by 6 ± 2 mmHg during 320 ADR and by 5 ± 2 mmHg during ATR + 80 ADR, and the change in calculated / was +2% in both conditions. When breathing 40% O2, which minimizes contributions from diffusion limitation and alveolar ventilation-to-perfusion inequality, the A–aDO2 increased by 12 ± 7 mmHg during 320 ADR, and by 9 ± 6 mmHg during ATR + 80 ADR, and the change in calculated / was +2% in both conditions. During 320 ADR cardiac output () and pulmonary artery systolic pressure (PASP) were significantly increased; however, during ATR + 80 ADR only was significantly increased, yet blood flow through IPAVAs as detected with saline contrast echocardiography was not different between conditions. Accordingly, we suggest that blood flow through IPAVAs provides a source of intrapulmonary shunt, and is mediated primarily by increases in rather than PASP. PMID:25085889

  7. Effect of Intake Air Filter Condition on Vehicle Fuel Economy

    SciTech Connect

    Norman, Kevin M; Huff, Shean P; West, Brian H

    2009-02-01

    The U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and the U.S. Environmental Protection Agency (EPA) jointly maintain a fuel economy website (www.fueleconomy.gov), which helps fulfill their responsibility under the Energy Policy Act of 1992 to provide accurate fuel economy information [in miles per gallon (mpg)] to consumers. The site provides information on EPA fuel economy ratings for passenger cars and light trucks from 1985 to the present and other relevant information related to energy use such as alternative fuels and driving and vehicle maintenance tips. In recent years, fluctuations in the price of crude oil and corresponding fluctuations in the price of gasoline and diesel fuels have renewed interest in vehicle fuel economy in the United States. (User sessions on the fuel economy website exceeded 20 million in 2008 compared to less than 5 million in 2004 and less than 1 million in 2001.) As a result of this renewed interest and the age of some of the references cited in the tips section of the website, DOE authorized the Oak Ridge National Laboratory (ORNL) Fuels, Engines, and Emissions Research Center (FEERC) to initiate studies to validate and improve these tips. This report documents a study aimed specifically at the effect of engine air filter condition on fuel economy. The goal of this study was to explore the effects of a clogged air filter on the fuel economy of vehicles operating over prescribed test cycles. Three newer vehicles (a 2007 Buick Lucerne, a 2006 Dodge Charger, and a 2003 Toyota Camry) and an older carbureted vehicle were tested. Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in

  8. Initial proof-of-principle for near room temperature Xe and Kr separation from air with MOFs

    SciTech Connect

    Thallapally, Praveen K.; Strachan, Denis M.

    2012-06-06

    Materials were developed and tested in support of the U.S. Department of Energy, Office of Nuclear Energy, Fuel Cycle Technology Separations and Waste Forms Campaign. Specifically, materials are being developed for the removal of Xenon and krypton from gaseous products of nuclear fuel reprocessing unit operations. During FY 2012, Three Metal organic framework (MOF) structures were investigated in greater detail for the removal and storage of Xe and Kr from air at room temperature. Our breakthrough measurements on Nickel based MOF could capture and separate parts per million levels of Xe from Air (40 ppm Kr, 78% N2, 21% O2, 0.9% Ar, 0.03% CO2). Similarly, the selectivity can be changed from Xe > Kr to Xe < Kr simply by changing the temperature in another MOF. Also for the first time we estimated the cost of the metal organic frameworks in bulk.

  9. In-Cab Air Quality of Trucks Air Conditioned and Kept in Electrified Truck Stop

    SciTech Connect

    Lee, Doh-Won; Zietsman, Josias; Farzaneh, Mohamadreza; Li, Wen-Whai; Olvera, Hector; Storey, John Morse; Kranendonk, Laura

    2009-01-01

    At night, long-haul truck drivers rest inside the cabins of their vehicles. Therefore, the in-cab air quality while air conditioning (A/C) is being provided can be a great concern to the drivers health. The effect of using different A/C methods [truck's A/C, auxiliary power unit (APU), and truck stop electrification (TSE) unit] on in-cab air quality of a heavy-duty diesel vehicle was investigated at an electrified truck stop in the El Paso, Texas, area. The research team measured the in-cabin and the ambient air quality adjacent to the parked diesel truck as well as emissions from the truck and an APU while it was providing A/C. The measured results were compared and analyzed. On the basis of these results, it was concluded that the TSE unit provided better in-cab air quality while supplying A/C. Furthermore, the truck and APU exhaust emissions were measured, and fuel consumption of the truck (while idling) and the APU (during operation) were compared. The results led to the finding that emissions from the APU were less than those from the truck's engine idling, but the APU consumed more fuel than the engine while providing A/C under given conditions.

  10. Performance of Desiccant Particle Dispersion Type Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Hatano, Hiroyuki; Suzuki, Koichi; Kojima, Hiromitsu

    An investigation of desiccant air conditioning system is performed to demonstrate its performance in a dispersed desiccant particle systems, based on its higher gas solid contacting efficiency and isothermal dehumidification. Particle dispersion is achieved using the risers of a circulating fluidized bed, CFB, or of a pneumatic conveyer. The risers used for dehumidification are 1390 mm in height and 22 mm in diameter. The former is used to evaluate the overall dehumidification performance and the latter is used to measure the axial humidity distribution under 0.88 m/s of a superficial air velocity. Based on the results of the overall performance by changing solid loading rates, Gs, from 0.4 kg/m2s up to 6 kg/m2s, desiccant particle dispersion shows higher performance in dehumidification, while axial humidity distribution shows very rapid adsorption rate in the entrance zone of the riser. Removal of adsorption heat accelerates dehumidification rate compared to the adiabatic process.

  11. Particulate composition characteristics under different ambient air quality conditions.

    PubMed

    Tsai, Jiun-Horng; Chang, Lisa Tzu-Chi; Huang, Yao-Sheng; Chiang, Hung-Lung

    2011-07-01

    Particulate compositions including elemental carbon (EC), organic carbon (OC), water-soluble ionic species, and elemental compositions were investigated during the period from 2004 to 2006 in southern Taiwan. The correlation between the pollutant standard index (PSI) of ambient air quality and the various particle compositions was also addressed in this study. PSI revealed a correlation with fine (r = 0.74) and coarse (r = 0.80) particulate matter (PM). PSI manifested a significant correlation with the amount of analyzed ionic species (r approximately 0.80) in coarse and fine particles and a moderate correlation with carbon content (r = 0.63) in fine particles; however, it showed no correlation with elemental content. Although the ambient air quality ranged from good to moderate, the ionic species including chloride (Cl-), nitrate (NO3-), sulfate (SO4(2-)), sodium (Na+), ammonium (NH4+), magnesium (Mg2+), and calcium (Ca2+) increased significantly (1.5-3.7 times for Daliao and 1.8-6.9 times for Tzouying) in coarse PM. For fine particles, NO3-, SO4(2-), NH4+, and potassium (K+) also increased significantly (1.3-2.4 times for Daliao and 2.8-9.6 times for Tzouying) when the air quality went from good to moderate. For meteorological parameters, temperature evidenced a slightly negative correlation with PM concentration and PSI value, which implied a high PM concentration in the low-temperature condition. This reflects the high frequency of PM episodes in winter and spring in southern Taiwan. In addition, the mixing height increase from 980 to 1450 m corresponds to the air quality condition changing from unhealthy to good. PMID:21850835

  12. SU-D-BRE-03: Dosimetric Impact of In-Air Spot Size Variations for Commissioning a Room-Matched Beam Model for Pencil Beam Scanning Proton Therapy

    SciTech Connect

    Zhang, Y; Giebeler, A; Mascia, A; Piskulich, F; Perles, L; Lepage, R; Dong, L

    2014-06-01

    Purpose: To quantitatively evaluate dosimetric consequence of spot size variations and validate beam-matching criteria for commissioning a pencil beam model for multiple treatment rooms. Methods: A planning study was first conducted by simulating spot size variations to systematically evaluate dosimetric impact of spot size variations in selected cases, which was used to establish the in-air spot size tolerance for beam matching specifications. A beam model in treatment planning system was created using in-air spot profiles acquired in one treatment room. These spot profiles were also acquired from another treatment room for assessing the actual spot size variations between the two treatment rooms. We created twenty five test plans with targets of different sizes at different depths, and performed dose measurement along the entrance, proximal and distal target regions. The absolute doses at those locations were measured using ionization chambers at both treatment rooms, and were compared against the calculated doses by the beam model. Fifteen additional patient plans were also measured and included in our validation. Results: The beam model is relatively insensitive to spot size variations. With an average of less than 15% measured in-air spot size variations between two treatment rooms, the average dose difference was −0.15% with a standard deviation of 0.40% for 55 measurement points within target region; but the differences increased to 1.4%±1.1% in the entrance regions, which are more affected by in-air spot size variations. Overall, our single-room based beam model in the treatment planning system agreed with measurements in both rooms < 0.5% within the target region. For fifteen patient cases, the agreement was within 1%. Conclusion: We have demonstrated that dosimetrically equivalent machines can be established when in-air spot size variations are within 15% between the two treatment rooms.

  13. Room Acoustics

    NASA Astrophysics Data System (ADS)

    Kuttruff, Heinrich; Mommertz, Eckard

    The traditional task of room acoustics is to create or formulate conditions which ensure the best possible propagation of sound in a room from a sound source to a listener. Thus, objects of room acoustics are in particular assembly halls of all kinds, such as auditoria and lecture halls, conference rooms, theaters, concert halls or churches. Already at this point, it has to be pointed out that these conditions essentially depend on the question if speech or music should be transmitted; in the first case, the criterion for transmission quality is good speech intelligibility, in the other case, however, the success of room-acoustical efforts depends on other factors that cannot be quantified that easily, not least it also depends on the hearing habits of the listeners. In any case, absolutely "good acoustics" of a room do not exist.

  14. Association between Ambient Air Pollution and Emergency Room Visits for Respiratory Diseases in Spring Dust Storm Season in Lanzhou, China

    PubMed Central

    Ma, Yuxia; Xiao, Bingshuang; Liu, Chang; Zhao, Yuxin; Zheng, Xiaodong

    2016-01-01

    Background: Air pollution has become a major global public health problem. A number of studies have confirmed the association between air pollutants and emergency room (ER) visits for respiratory diseases in developed countries and some Asian countries, but little evidence has been seen in Western China. This study aims to concentrate on this region. Methods: A time-series analysis was used to examine the specific effects of major air pollutants (PM10, SO2 and NO2) on ER visits for respiratory diseases from 2007 to 2011 in the severely polluted city of Lanzhou. We examined the effects of air pollutants for stratified groups by age and gender, accounting for the modifying effect of dust storms in spring to test the possible interaction. Results: Significant associations were found between outdoor air pollution concentrations and respiratory diseases, as expressed by daily ER visits in Lanzhou in the spring dust season. The association between air pollution and ER visits appeared to be more evident on dust days than non-dust days. Relative risks (RRs) and 95% CIs per 10 µg/m3 increase in 3-day PM10 (L3), 5-day SO2 (L5), and the average of current and previous 2-day NO2 (L01) were 1.140 (1.071–1.214), 1.080 (0.967–1.205), and 1.298 (1.158–1.454), respectively, on dust days. More significant associations between PM10, SO2 and NO2 and ER visits were found on dust days for elderly females, elderly males and adult males, respectively. Conclusions: This study strengthens the evidence of dust-exacerbated ER visits for respiratory diseases in Lanzhou. PMID:27338430

  15. Analysis of non-CFC automotive air conditioning

    SciTech Connect

    Mei, V.C.; Chen, F.C. ); Sullivan, R.A. )

    1991-01-01

    Concern about the destruction of the global environment by chlorofluorocarbon (CFC) fluids has become an impetus in searching for alternative non-CFC refrigerants and cooling methods for mobile air conditioning (MAC). While some alternative refrigerants have been identified, they are not considered a lasting solution because of their high global warming potential (GWP), which could result in their eventual phase-out. In view of this dilemma, environmentally acceptable alternative cooling methods have become important. This study discusses the advantages and the limits of some of the alternative automotive cooling methodologies. 19 refs., 6 figs.

  16. Liquid over-feeding air conditioning system and method

    DOEpatents

    Mei, V.C.; Chen, F.C.

    1993-09-21

    A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant. 1 figure.

  17. Liquid over-feeding air conditioning system and method

    DOEpatents

    Mei, Viung C.; Chen, Fang C.

    1993-01-01

    A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant.

  18. Use of waste heat for automotive air conditioning

    SciTech Connect

    Hamner, R.M.

    1981-01-01

    The ejector-compression refrigeration system, a heat powered system which can be operated as a heat pump, is described. The operation of the system is discussed in general and the ejector itself is described in more detail. The central thrust of the paper is the application of the system to comfort air conditioning of automobiles. The advantages, limitations, and recommendations for future research and development are given. Several analyses of the theoretical cycle are made and equations describing the operation of the ejector are derived. A brief bibliography is listed.

  19. Do-It-Yourself Additives Recharge Auto Air Conditioning

    NASA Technical Reports Server (NTRS)

    2010-01-01

    In planning for a return mission to the Moon, NASA aimed to improve the thermal control systems that keep astronauts comfortable and cool while inside a spacecraft. Goddard Space Flight Center awarded a Small Business Innovation Research (SBIR) contract to Mainstream Engineering Corporation, of Rockledge, Florida, to develop a chemical/mechanical heat pump. IDQ Inc., of Garland, Texas, exclusively licensed the technology and incorporates it into its line of Arctic Freeze products for automotive air conditioning applications. While working on the design, Mainstream Engineering came up with a unique liquid additive called QwikBoost to enhance the performance of the advanced heat pump design.

  20. Lithium-air batteries using hydrophobic room temperature ionic liquid electrolyte

    NASA Astrophysics Data System (ADS)

    Kuboki, Takashi; Okuyama, Tetsuo; Ohsaki, Takahisa; Takami, Norio

    Lithium-air batteries using hydrophobic ionic liquid consisting of 1-alkyl-3-methyl imidazolium cation and perfluoroalkylsulfonyl imide anion were investigated. 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide, which has high conductivity and prevents hydrolysis of the lithium anode, showed the best electrolyte performance. The cell worked for 56 days in air, and the cathode carbon materials showed high discharge capacity of 5360 mAh g -1. In addition to hydrophobic ionic liquids for use as electrolytes, various carbon materials for use as high-capacity cathodes were investigated.

  1. Metal-air cell comprising an electrolyte with a room temperature ionic liquid and hygroscopic additive

    DOEpatents

    Friesen, Cody A.; Krishnan, Ramkumar; Tang, Toni; Wolfe, Derek

    2014-08-19

    An electrochemical cell comprising an electrolyte comprising water and a hydrophobic ionic liquid comprising positive ions and negative ions. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. A hydrophilic or hygroscopic additive modulates the hydrophobicity of the ionic liquid to maintain a concentration of the water in the electrolyte is between 0.001 mol % and 25 mol %.

  2. On the impact of entrapped air in infiltration under ponding conditions. Part a: Preferential air flow path effects on infiltration

    NASA Astrophysics Data System (ADS)

    Mizrahi, Guy; Weisbrod, Noam; Furman, Alex

    2015-04-01

    Entrapped air effects on infiltration under ponding conditions could be important for massive infiltration of managed aquifer recharge (MAR) or soil aquifer treatment (SAT) of treated wastewater. Earlier studies found that under ponding conditions, air is being entrapped and compressed until it reaches a pressure which will enable the air to escape (unstable air flow). They also found that entrapped air could reduce infiltration by 70-90%. Most studies have dealt with entrapped air effects when soil surface topography is flat. The objective of this study is to investigate, under ponding conditions, the effects of: (1) irregular surface topography on preferential air flow path development (stable air flow); (2) preferential air flow path on infiltration; and (3) hydraulic head on infiltration when air is trapped. Column experiments were used to investigate these particular effects. A 140 cm deep and 30 cm wide column packed with silica sand was used under two boundary conditions: in the first, air can only escape vertically upward through the soil surface; in the second, air is free to escape through 20 ports installed along the column perimeter. The surface was flooded with 13 liters of water, with ponding depth decreasing with time. Two soil surface conditions were tested: flat surface and irregular surface (high and low surface zones). Additionally, Helle-show experiments were conducted in order to obtain a visual observation of preferential air flow path development. The measurements were carried out using a tension meter, air pressure transducers, TDR and video cameras. It was found that in irregular surfaces, stable air flow through preferential paths was developed in the high altitude zones. Flat surface topography caused unstable air flow through random paths. Comparison between irregular and flat surface topography showed that the entrapped air pressure was lower and the infiltration rate was about 40% higher in the irregular surface topography than in the

  3. Absorption and adsorption chillers applied to air conditioning systems

    NASA Astrophysics Data System (ADS)

    Kuczyńska, Agnieszka; Szaflik, Władysław

    2010-07-01

    This work presents an application possibility of sorption refrigerators driven by low temperature fluid for air conditioning of buildings. Thermodynamic models were formulated and absorption LiBr-water chiller with 10 kW cooling power as well as adsorption chiller with silica gel bed were investigated. Both of them are using water for desorption process with temperature Tdes = 80 °C. Coefficient of performance (COP) for both cooling cycles was analyzed in the same conditions of the driving heat source, cooling water Tc = 25 °C and temperature in evaporator Tevap = 5 °C. In this study, the computer software EES was used to investigate the performance of absorption heat pump system and its behaviour in configuration with geothermal heat source.

  4. Guidelines on Thermal Comfort of Air Conditioned Indoor Environment

    NASA Astrophysics Data System (ADS)

    Miura, Toyohiko

    The thermal comfort of air conditioned indoor environment for workers depended, of course, on metabolic rate of work, race, sex, age, clothing, climate of the district and state of acclimatization. The attention of the author was directed to the seasonal variation and the sexual difference of comfortable temperature and a survey through a year was conducted on the thermal comfort, and health conditions of workers engaged in light work in a precision machine factory, in some office workers. Besides, a series of experiments were conducted for purpose of determinning the optimum temperature of cooling in summer time in relation to the outdoor temperature. It seemed that many of workers at present would prefer somewhat higher temperature than those before the World War II. Forty years ago the average homes and offices were not so well heated as today, and clothing worn on the average was considerably heavier.

  5. A Knoevenagel Initiated Annulation Reaction Using Room Temperature or Microwave Conditions

    ERIC Educational Resources Information Center

    Cook, A. Gilbert

    2007-01-01

    An experiment is presented that has the student execute a Knoevenagel initiated annulation reaction. The reaction can be carried out either through use of a microwave reactor or by allowing the mixture to stand at room temperature for two days. The student is then challenged to identify the reaction product through a guided prelab exercise of the…

  6. Effects of Air Pollution on Hospital Emergency Room Visits for Respiratory Diseases: Urban-Suburban Differences in Eastern China

    PubMed Central

    Liu, Peng; Wang, Xining; Fan, Jiayin; Xiao, Wenxin; Wang, Yan

    2016-01-01

    A study on the relationships between ambient air pollutants (PM2.5, SO2 and NO2) and hospital emergency room visits (ERVs) for respiratory diseases from 2013 to 2014 was performed in both urban and suburban areas of Jinan, a heavily air-polluted city in Eastern China. This research was analyzed using generalized additive models (GAM) with Poisson regression, which controls for long-time trends, the “day of the week” effect and meteorological parameters. An increase of 10 μg/m3 in PM2.5, SO2 and NO2 corresponded to a 1.4% (95% confidence interval (CI): 0.7%, 2.1%), 1.2% (95% CI: 0.5%, 1.9%), and 2.5% (95%: 0.8%, 4.2%) growth in ERVs for the urban population, respectively, and a 1.5% (95%: 0.4%, 2.6%), 0.8% (95%: −0.7%, 2.3%), and 3.1% (95%: 0.5%, 5.7%) rise in ERVs for the suburban population, respectively. It was found that females were more susceptible than males to air pollution in the urban area when the analysis was stratified by gender, and the reverse result was seen in the suburban area. Our results suggest that the increase in ERVs for respiratory illnesses is linked to the levels of air pollutants in Jinan, and there may be some urban-suburban discrepancies in health outcomes from air pollutant exposure. PMID:27007384

  7. Actual Performance Prediction of Split-type Room Air Conditioner which Considered Unsteady Operation Concerning Heat Island Problem

    NASA Astrophysics Data System (ADS)

    Shinomiya, Naruaki; Nishimura, Nobuya; Iyota, Hiroyuki; Nomura, Tomohiro

    Split type air conditioners are operated actually in the situation unlike the condition that was described in a product catalog. On the other hand, exhaust heat from air conditioner is considered as one of the causes of heat island problem in urban area, and the air conditioner performance and heat load affect exhaust heat amount. In this study, air conditioner performances in both standard summer day and severe hot day were examined by dynamic simulation which considered outdoor weather changes. As a result, actual performances of the air conditioner were demonstrated as a function of outdoor temperature, heat load and indoor temperature. The higher the outdoor temperature and heat load rise, the smaller influences of indoor temperature against COP became. In standard summer day, relative performance exceeded by 15 to 45% than that of JIS operating condition. Also, COP in severe hot day decreased about 6% at the peak time than that of standard day. As a result, the air conditioner exhaust heat during one day which was predicted by the proposed simulation model became about 16% smaller than the conventional prediction model.

  8. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... alternative air conditioning test simulations. (a) Upon petition from a manufacturer or upon the Agency's own initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  9. 24 CFR 3280.813 - Outdoor outlets, fixtures, air-conditioning equipment, etc.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Electrical Systems § 3280.813 Outdoor outlets, fixtures, air-conditioning equipment, etc. (a) Outdoor.../or air conditioning equipment located outside the manufactured home, shall have permanently affixed, adjacent to the outlet, a metal tag which reads: This Connection Is for Air Conditioning Equipment Rated...

  10. Prediction of Air Conditioning Load Response for Providing Spinning Reserve - ORNL Report

    SciTech Connect

    Kueck, John D; Kirby, Brendan J; Ally, Moonis Raza; Rice, C Keith

    2009-02-01

    This report assesses the use of air conditioning load for providing spinning reserve and discusses the barriers and opportunities. Air conditioning load is well suited for this service because it often increases during heavy load periods and can be curtailed for short periods with little impact to the customer. The report also provides an appendix describing the ambient temperature effect on air conditioning load.

  11. 14 CFR 203.5 - Compliance as condition on operations in air transportation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Compliance as condition on operations in... DEFENSES § 203.5 Compliance as condition on operations in air transportation. It shall be a condition on... 18900 as fully as if that air carrier or foreign air carrier had in fact filed a properly...

  12. 14 CFR 203.5 - Compliance as condition on operations in air transportation.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Compliance as condition on operations in... DEFENSES § 203.5 Compliance as condition on operations in air transportation. It shall be a condition on... 18900 as fully as if that air carrier or foreign air carrier had in fact filed a properly...

  13. 14 CFR 203.5 - Compliance as condition on operations in air transportation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Compliance as condition on operations in... DEFENSES § 203.5 Compliance as condition on operations in air transportation. It shall be a condition on... 18900 as fully as if that air carrier or foreign air carrier had in fact filed a properly...

  14. 14 CFR 203.5 - Compliance as condition on operations in air transportation.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 4 2012-01-01 2012-01-01 false Compliance as condition on operations in... DEFENSES § 203.5 Compliance as condition on operations in air transportation. It shall be a condition on... 18900 as fully as if that air carrier or foreign air carrier had in fact filed a properly...

  15. Investigation of Room Temperature Oxidation of Cu in Air by Yoneda-XAFS

    SciTech Connect

    Keil, P.; Luetzenkirchen-Hecht, D.; Frahm, R.

    2007-02-02

    The structure of thin copper oxide layers which are formed on metallic Cu due to the exposure to air are investigated with Yoneda-XAFS and ReflEXAFS. The measured Yoneda-XAFS data were compared to quantitative model calculations in the framework of the distorted wave Born approximation (DWBA) assuming different model structures for the oxide layer. Yoneda-XAFS fine structure spectra measured for various different grazing angles show that the experimental data are best described by a model structure consisting of a duplex type oxide layer with an outer layer of CuO (tenorite) in direct contact with the gas atmosphere and an inner Cu2O (cuprite) layer at the interface to the underlying Cu metal.

  16. The effect of simulated air conditions on N95 filtering facepiece respirators performance.

    PubMed

    Ramirez, Joel A; O'Shaughnessy, Patrick T

    2016-07-01

    The objective of this study was to determine the effect of several simulated air environmental conditions on the particle penetration and the breathing resistance of two N95 filtering facepiece respirator (FFR) models. The particle penetration and breathing resistance of the respirators were evaluated in a test system developed to mimic inhalation and exhalation breathing while relative humidity and temperature were modified. Breathing resistance was measured over 120 min using a calibrated pressure transducer under four different temperature and relative humidity conditions without aerosol loading. Particle penetration was evaluated before and after the breathing resistance test at room conditions using a sodium chloride aerosol measured with a scanning mobility particle sizer. Results demonstrated that increasing relative humidity and lowering external temperature caused significant increases in breathing resistance (p < 0.001). However, these same conditions did not influence the penetration or most penetrating particle size of the tested FFRs. The increase in breathing resistance varied by FFR model suggesting that some FFR media are less influenced by high relative humidity. PMID:26861653

  17. Inactivation of a 25.5 µm Enterococcus faecalis biofilm by a room-temperature, battery-operated, handheld air plasma jet

    NASA Astrophysics Data System (ADS)

    Pei, X.; Lu, X.; Liu, J.; Liu, D.; Yang, Y.; Ostrikov, K.; Chu, Paul K.; Pan, Y.

    2012-04-01

    Effective biofilm inactivation using a handheld, mobile plasma jet powered by a 12 V dc battery and operated in open air without any external gas supply is reported. This cold, room-temperature plasma is produced in self-repetitive nanosecond discharges with current pulses of ˜100 ns duration, current peak amplitude of ˜6 mA and repetition rate of ˜20 kHz. It is shown that the reactive plasma species penetrate to the bottom layer of a 25.5 µm-thick Enterococcus faecalis biofilm and produce a strong bactericidal effect. This is the thickest reported biofilm inactivated using room-temperature air plasmas.

  18. Investigation of nitrogen and carbon co-implantation under room temperature and cryo-condition

    NASA Astrophysics Data System (ADS)

    He, Yonggen; Wu, Bing; Yu, Guobin; Chen, Yong; Liu, Hailong; He, Youfeng; Dai, Haibo; Wu, Jingang; Zhang, David Wei; Lu, Junfeng; Xu, Jingrui; Guo, Baonian

    2012-11-01

    Co-implantation of non-dopant species is widely used in 65nm and beyond Complementary Metal-Oxide-Semiconductor (CMOS) technology node to meet ITRS ultra shallow junction roadmap and device performance requirement. With co-implantation, non-dopant species, such as Carbon (C), Fluorine (F) and Nitrogen (N), can either suppress doping diffusion or modify material property and improve device reliability. Cold implantation with wafer pedestal cooling to near -100°C is another hot topic in CMOS manufacture recently. It has obvious benefits, such as good amorphization performance, less end of range defect, less stress relaxation especially for e-SiGe formation. In the present work, different co-implantations with nitrogen and/or carbon were investigated for advanced NMOS Lightly Doped Drain (LDD) junction formation. The co-implantation was performed under room temperature or -100°C. It was found that C or C plus N co-implantations are very effective to suppress the diffusion of halo-implanted boron. Comparing with room temperature, the cryo-implantation under -100°C can get much better amorphization and less End of Range (EOR) defects, which result in reduced junction leakage and high activation as observed on blanket wafer and device wafers.

  19. Indoor air quality and energy performance of air-conditioned office buildings in Singapore.

    PubMed

    Sekhar, S C; Tham, K W; Cheong, K W

    2003-12-01

    An integrated indoor air quality (IAQ)-energy audit methodology has been developed in this study in Singapore, which provides a rigorous and systematic method of obtaining the status-quo assessment of an 'IAQ signature' in a building. The methodology entails a multi-disciplinary model in obtaining measured data pertaining to different dimensions within the built environment such as the physical, chemical, biological, ventilation, and occupant response characteristics. This paper describes the audit methodology and presents the findings from five air-conditioned office buildings in Singapore. The research has also led to the development of an indoor pollutant standard index (IPSI), which is discussed in this paper. Other performance indicators such as, the ventilation index and the energy index as well as the building symptom index (BSI) are also presented and discussed in the context of an integrated approach to IAQ and energy. Several correlation attempts were made on the various symptoms, indoor air acceptability, thermal comfort, BSI and IPSI, and while BSI values are found to correlate among them as well as with IAQ and THERMAL COMFORT acceptability, no such correlation was observed between BSI and IPSI. This would suggest that the occupants' perception of symptoms experienced as well as environmental acceptability is quite distinct from IAQ acceptability determined from empirical measurements of indoor pollutants, which reinforces the complex nature of IAQ issues. PMID:14636226

  20. Understanding the Dehumidification Performance of Air-Conditioning Equipment at Part-Load Conditions

    SciTech Connect

    Don B. Shirey III; Hugh I. Henderson Jr; Richard A. Raustad

    2006-01-01

    Air conditioner cooling coils typically provide both sensible cooling and moisture removal. Data from a limited number of field studies (Khattar et al. 1985; Henderson and Rengarajan 1996; Henderson 1998) have demonstrated that the moisture removal capacity of a cooling coil degrades at part-load conditions--especially when the supply fan operates continuously while the cooling coil cycles on and off. Degradation occurs because moisture that condenses on the coil surfaces during the cooling cycle evaporates back into air stream when the coil is off. This degradation affects the ability of cooling equipment to maintain proper indoor humidity levels and may negatively impact indoor air quality. This report summarizes the results of a comprehensive project to better understand and quantify the moisture removal (dehumidification) performance of cooling coils at part-load conditions. A review of the open literature was initially conducted to learn from previous research on this topic. Detailed performance measurements were then collected for eight cooling coils in a controlled laboratory setting to understand the impact of coil geometry and operating conditions on transient moisture condensation and evaporation by the coils. Measurements of cooling coil dehumidification performance and space humidity levels were also collected at seven field test sites. Finally, an existing engineering model to predict dehumidification performance degradation for single-stage cooling equipment at part-load conditions (Henderson and Rengarajan 1996) was enhanced to include a broader range of fan control strategies and an improved theoretical basis for modeling off-cycle moisture evaporation from cooling coils. The improved model was validated with the laboratory measurements, and this report provides guidance for users regarding proper model inputs. The model is suitable for use in computerized calculation procedures such as hourly or sub-hourly building energy simulation programs (e

  1. Cooling System Using Natural Circulation for Air Conditioning

    NASA Astrophysics Data System (ADS)

    Okazaki, Takashi; Seshimo, Yu

    In this paper, Cooling systems with natural circulation loop of refrigerants are reviewed. The cooling system can largely reduce energy consumption of a cooling system for the telecommunication base site. The cooling system consists of two refrigeration units; vapor compression refrigeration unit and sub-cooling unit with a natural-circulation loop. The experiments and calculations were carried out to evaluate the cycle performance of natural circulation loop with HFCs and CO2. The experimental results showed that the cooling capacity of R410A is approximately 30% larger than that of R407C at the temperature difference of 20K and the cooling capacity of CO2 was approximately 4-13% larger than that of R410A under the two-phase condition. On the other hand, the cooling capacity of CO2 was approximately 11% smaller than that of R410A under the supercritical condition. The cooling capacity took a maximum value at an amount of refrigerant and lineally increased as the temperature difference increases and the slightly increased as the height difference. The air intake temperature profile in the inlet of the heat exchangers makes the reverse circulation under the supercritical state and the driving head difference for the reverse circulation depends on the density change to temperature under the supercritical state. Also, a new fan control method to convert the reverse circulation into the normal circulation was reviewed.

  2. Airflow analysis in mechanically ventilated obstructed rooms

    NASA Astrophysics Data System (ADS)

    Priest, John Brian

    1999-11-01

    Local and mean air velocities and standard deviations were measured in realistic rooms. Obstructions represented occupants and equipment in the rooms, internal heat loads varied and supply air temperature differed from room averages. Experimental setups differed for the isothermal and nonisothermal tests. Room dimensions for isothermal tests were 2.44 m high by 4.88 x 4.88 m. Ten different obstruction ratios using three different inlet types were analyzed. Obstructions covered 0 to 30% floor area and from 0 to 75% of room height. Air was supplied at ventilation rates ranging between 0.8 and 1.1 m 3/s. Room dimensions for the nonisothermal tests were 2.44 m high by 3.66 x 7.32 m. Obstruction differences between solid versus open partitions for farrowing crates were investigated for three commercially available inlets using two ventilation loads. Ventilation rates were 0.11 to 1.18 m 3/s, simulating cold and warm weather ventilation conditions, respectively. Based on these data and theoretical calculations, a kinetic energy model that predicts average room air velocity and energy level was developed as a practical room air flow design and analysis tool. It was recommended that designers interested in using CFD as a tool should use a three dimensional laminar model for acceptable qualitative flow results. It was concluded that for typical room flowrates and inlet types the room air distribution system is obstruction ratio independent. Local velocities and standard deviations varied with each obstruction setup and inlet combination. However, average air velocities and turbulence intensities were not influenced by obstruction setups or inlet configurations. The decay rate of mean velocity kinetic energy in the bulk flow region was independent of obstructions and inlets. Room average kinetic energy was a function of the supplied kinetic energy within the supply jet plus internal kinetic energy resulting from internal heat load (convective energy).

  3. China Energy Efficiency Round Robin Testing Results for Room Air Conditioners

    SciTech Connect

    Zhou, Nan; Fridley, David; Zheng, Nina; Pierrot, Andre

    2010-06-07

    of all countries energy strategies. As we all know, a very large amount of total energy consumption is due to energy consuming products and equipment, which account for about 50% of China's total energy consumption. However, the current average energy utilization efficiency of this sector is only about 60%, 10 percent lower than the international advanced level. Therefore, China's energy consuming products and equipment sector holds great energy-saving potential. On the other hand, the energy supplied to these products is mainly from fossil fuel combustion, a major source of greenhouse gas (GHG) emissions. Therefore, improving the energy efficiency and augmenting the market share of market-dominant energy consuming products is of significant importance to achieving China's energy saving and emission reduction target and is an effective means to deal with energy and environmental constraints and climate change issues. Main energy consuming products generally include widely-used home appliances, industrial equipment, office equipment, transportation vehicles, etc. China is one of the major manufacturers and exporters of energy end-using products such as air-conditioners, refrigerators, televisions, etc. Their overall energy efficiency is comparatively low and the products are poorly designed, leading to great energy-saving potential. For example, electricity consumption of air conditioners accounts for about 20% of China's total electricity consumption and 40% of the summer electricity peak load in large and medium cities. However, less than 5% of units sold in the domestic market in 2009 reached the standard's highly efficient level of grade 2 above. The electricity consumption of electric motors and their related drive systems accounts for about 60% of China's total electricity consumption; however, less than 2% of the domestic market share consists of energy-efficient electric motor products. Promoting the energy efficiency and market shares of main energy

  4. Large Animal Model of Pumpless Arteriovenous Extracorporeal CO₂ Removal Using Room Air via Subclavian Vessels.

    PubMed

    Witer, Lucas J; Howard, Ryan A; Trahanas, John M; Bryner, Benjamin S; Alghanem, Fares; Hoffman, Hayley R; Cornell, Marie S; Bartlett, Robert H; Rojas-Peña, Alvaro

    2016-01-01

    End-stage lung disease (ESLD) causes progressive hypercapnia and dyspnea and impacts quality of life. Many extracorporeal support (ECS) configurations for CO2 removal resolve symptoms but limit ambulation. An ovine model of pumpless ECS using subclavian vessels was developed to allow for ambulatory support. Vascular grafts were anastomosed to the left subclavian vessels in four healthy sheep. A low-resistance membrane oxygenator was attached in an arteriovenous (AV) configuration. Device function was evaluated in each animal while awake and spontaneously breathing and while mechanically ventilated with hypercapnia induced. Sweep gas (FiO2 = 0.21) to the device was increased from 0 to 15 L/min, and arterial and postdevice blood gases, as well as postdevice air, were sampled. Hemodynamics remained stable with average AV shunt flows of 1.34 ± 0.14 L/min. In awake animals, CO2 removal was 3.4 ± 1.0 ml/kg/min at maximum sweep gas flow. Respiratory rate decreased from 60 ± 25 at baseline to 30 ± 11 breaths per minute. In animals with induced hypercapnia, PaCO2 increased to 73.9 ± 15.1. At maximum sweep gas flow, CO2 removal was 3.4 ± 0.4 ml/kg/min and PaCO2 decreased to 49.1 ± 6.7 mm Hg. Subclavian AV access is effective in lowering PaCO2 and respiratory rate and is potentially an effective ambulatory destination therapy for ESLD patients. PMID:26461241

  5. On the impact of entrapped air in infiltration under ponding conditions: Part a: Preferential air flow path effects on infiltration

    NASA Astrophysics Data System (ADS)

    Weisbord, N.; Mizrahi, G.; Furman, A.

    2015-12-01

    Entrapped air effects on infiltration under ponding conditions could be important for massive infiltration of managed aquifer recharge or soil aquifer treatment. Earlier studies found that under ponding conditions air could reduce infiltration by 70-90%. Most studies have dealt with entrapped air effects when soil surface topography is flat. The objective of this study is to investigate the effects of: (1) irregular surface topography on preferential air flow path development; (2) preferential air flow path on infiltration; and (3) hydraulic head on infiltration when air is trapped. Column experiments were used to investigate these particular effects. A 140 cm deep and 30 cm wide column packed with silica sand was used under two boundary conditions: in the first, air can only escape vertically upward through the soil surface; in the second, air is free to escape. The surface was flooded with 13 liters of water, with ponding depth decreasing with time. Two soil surface conditions were tested: flat surface and irregular. It was found that in irregular surfaces, stable air flow through preferential paths was developed in the high altitude zones. Flat surface topography caused unstable air flow through random paths. Comparison between irregular and flat surface topography showed that the entrapped air pressure was lower and the infiltration rate was about 40% higher in the irregular surface topography than in the flat surface topography. No difference of infiltration rate between flat and irregular surface topography was observed when air was free to escape along the infiltration path. It was also found that at the first stage of infiltration, higher hydraulic heads caused higher entrapped air pressures and lower infiltration rates. In contrast, higher hydraulic head results in higher infiltration rate, when air was free to escape. Our results suggest that during ponding conditions: (1) preferential air flow paths develop at high surface zones of irregular topography

  6. Weather conditions and visits to the medical wing of emergency rooms in a metropolitan area during the warm season in Israel: a predictive model.

    PubMed

    Novikov, Ilya; Kalter-Leibovici, Ofra; Chetrit, Angela; Stav, Nir; Epstein, Yoram

    2012-01-01

    Global climate changes affect health and present new challenges to healthcare systems. The aim of the present study was to analyze the pattern of visits to the medical wing of emergency rooms (ERs) in public hospitals during warm seasons, and to develop a predictive model that will forecast the number of visits to ERs 2 days ahead. Data on daily visits to the ERs of the four largest medical centers in the Tel-Aviv metropolitan area during the warm months of the year (April-October, 2001-2004), the corresponding daily meteorological data, daily electrical power consumption (a surrogate marker for air-conditioning), air-pollution parameters, and calendar information were obtained and used in the analyses. The predictive model employed a time series analysis with transitional Poisson regression. The concise multivariable model was highly accurate (r (2) = 0.819). The contribution of mean daily temperature was small but significant: an increase of 1°C in ambient temperature was associated with a 1.47% increase in the number of ER visits (P < 0.001). An increase in electrical power consumption significantly attenuated the effect of weather conditions on ER visits by 4% per 1,000 MWh (P < 0.001). Higher daily mean SO(2) concentrations were associated with a greater number of ER visits (1% per 1 ppb increment; P = 0.017). Calendar data were the main predictors of ER visits (r (2) = 0.794). The predictive model was highly accurate in forecasting the number of visits to ERs 2 days ahead. The marginal effect of temperature on the number of ER visits can be attributed to behavioral adaptations, including the use of air-conditioning. PMID:21267601

  7. Room temperature epitaxy of Pd films on GaN under conventional vacuum conditions

    NASA Astrophysics Data System (ADS)

    Liu, Q. Z.; Lau, S. S.; Perkins, N. R.; Kuech, T. F.

    1996-09-01

    Pd films deposited at room temperature have been found to grow epitaxially on GaN grown by metalorganic vapor phase epitaxy (MOVPE). The Pd films were deposited on GaN substrates cleaned by chemicals only, and in a conventional e-beam evaporation system with a vacuum of ˜1×10-7 Torr. MeV 4He backscattering spectrometry and the Read x-ray camera were used to evaluate the Pd films. The effects of various chemical etchants—such as aqua regia, HCl:H2O, and HF:H2O—on the epitaxial quality of the Pd films have also been investigated. Ni and Pt films deposited on GaN in a similar manner were also found to be epitaxial.

  8. Liquid Desiccant in Air Conditioners: Nano-Engineered Porous Hollow Fiber Membrane-Based Air Conditioning System

    SciTech Connect

    2010-09-02

    BEETIT Project: UTRC is developing an air conditioning system that is optimized for use in warm and humid climates. UTRC’s air conditioning system integrates a liquid drying agent or desiccant and a traditional vapor compression system found in 90% of air conditioners. The drying agent reduces the humidity in the air before it is cooled, using less energy. The technology uses a membrane as a barrier between the air and the liquid salt stream allowing only water vapor to pass through and not the salt molecules. This solves an inherent problem with traditional liquid desiccant systems—carryover of the liquid drying agent into the conditioned air stream—which eliminates corrosion and health issues

  9. Validation of two air quality models for Indian mining conditions.

    PubMed

    Chaulya, S K; Ahmad, M; Singh, R S; Bandopadhyay, L K; Bondyopadhay, C; Mondal, G C

    2003-02-01

    All major mining activity particularly opencast mining contributes to the problem of suspended particulate matter (SPM) directly or indirectly. Therefore, assessment and prediction are required to prevent and minimize the deterioration of SPM due to various opencast mining operations. Determination of emission rate of SPM for these activities and validation of air quality models are the first and foremost concern. In view of the above, the study was taken up for determination of emission rate for SPM to calculate emission rate of various opencast mining activities and validation of commonly used two air quality models for Indian mining conditions. To achieve the objectives, eight coal and three iron ore mining sites were selected to generate site specific emission data by considering type of mining, method of working, geographical location, accessibility and above all resource availability. The study covers various mining activities and locations including drilling, overburden loading and unloading, coal/mineral loading and unloading, coal handling or screening plant, exposed overburden dump, stock yard, workshop, exposed pit surface, transport road and haul road. Validation of the study was carried out through Fugitive Dust Model (FDM) and Point, Area and Line sources model (PAL2) by assigning the measured emission rate for each mining activity, meteorological data and other details of the respective mine as an input to the models. Both the models were run separately for the same set of input data for each mine to get the predicted SPM concentration at three receptor locations for each mine. The receptor locations were selected such a way that at the same places the actual filed measurement were carried out for SPM concentration. Statistical analysis was carried out to assess the performance of the models based on a set measured and predicted SPM concentration data. The value of coefficient of correlation for PAL2 and FDM was calculated to be 0.990-0.994 and 0

  10. 15. Readiness Crew Building interior, Room 105, former briefing room, ...

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

    15. Readiness Crew Building interior, Room 105, former briefing room, looking northwest. Projection room in at the back wall. Thalheimer - Whiteman Air Force Base, Bomber Alert Facility S-6, 1300 Alert Road, Knob Noster, Johnson County, MO

  11. 32 CFR 809a.9 - Conditions for use of Air Force resources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Conditions for use of Air Force resources. 809a.9 Section 809a.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... Disturbance Intervention and Disaster Assistance § 809a.9 Conditions for use of Air Force resources. This...

  12. 32 CFR 809a.9 - Conditions for use of Air Force resources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Conditions for use of Air Force resources. 809a.9 Section 809a.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... Disturbance Intervention and Disaster Assistance § 809a.9 Conditions for use of Air Force resources. This...

  13. 32 CFR 809a.9 - Conditions for use of Air Force resources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Conditions for use of Air Force resources. 809a.9 Section 809a.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... Disturbance Intervention and Disaster Assistance § 809a.9 Conditions for use of Air Force resources. This...

  14. 32 CFR 809a.9 - Conditions for use of Air Force resources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Conditions for use of Air Force resources. 809a.9 Section 809a.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... Disturbance Intervention and Disaster Assistance § 809a.9 Conditions for use of Air Force resources. This...

  15. 32 CFR 809a.9 - Conditions for use of Air Force resources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Conditions for use of Air Force resources. 809a.9 Section 809a.9 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE... Disturbance Intervention and Disaster Assistance § 809a.9 Conditions for use of Air Force resources. This...

  16. Assessing summertime urban air conditioning consumption in a semiarid environment

    NASA Astrophysics Data System (ADS)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Wang, M.; Svoma, B. M.

    2013-09-01

    Evaluation of built environment energy demand is necessary in light of global projections of urban expansion. Of particular concern are rapidly expanding urban areas in environments where consumption requirements for cooling are excessive. Here, we simulate urban air conditioning (AC) electric consumption for several extreme heat events during summertime over a semiarid metropolitan area with the Weather Research and Forecasting (WRF) model coupled to a multilayer building energy scheme. Observed total load values obtained from an electric utility company were split into two parts, one linked to meteorology (i.e., AC consumption) which was compared to WRF simulations, and another to human behavior. WRF-simulated non-dimensional AC consumption profiles compared favorably to diurnal observations in terms of both amplitude and timing. The hourly ratio of AC to total electricity consumption accounted for ˜53% of diurnally averaged total electric demand, ranging from ˜35% during early morning to ˜65% during evening hours. Our work highlights the importance of modeling AC electricity consumption and its role for the sustainable planning of future urban energy needs. Finally, the methodology presented in this article establishes a new energy consumption-modeling framework that can be applied to any urban environment where the use of AC systems is prevalent.

  17. Study on the Efficient Drive of a Desiccant Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Jeong, Jong-Soo; Saito, Kiyoshi; Kawai, Sunao

    This paper constructs the static simulation model of a desiccant air conditioning system and gives the guidelines for the efficient drive of the desiccant air conditioning system. The desiccant air conditioning system is composed of a desiccant wheel, a heat exchanger, two evaporative coolers and a heater. The process air and regeneration air are supplied to this system. The desiccant is Silica gel. In the simulation model, two-dimensional model in space is adopted for the desiccant wheel. As the simulation result, it is clarified that optimum outlet temperature of the regeneration air in the heater, rotational speed of the desiccant wheel, the rejected air flow rate of the regeneration air, the process and regeneration air flow rate that maximize COP exist. For example, in case that the regeneration temperature is 63°C and relative humidity is 55% maximum COP is about 0.62.

  18. Multivariate analysis comparing microbial air content of an air-conditioned building and a naturally ventilated building over one year

    NASA Astrophysics Data System (ADS)

    Parat, Sylvie; Perdrix, Alain; Fricker-Hidalgo, Hélène; Saude, Isabelle; Grillot, Renee; Baconnier, Pierre

    Heating, ventilation and air-conditioning (HVAC) may be responsible for the production and spread of airborne microorganisms in office buildings. In order to compare airborne microbiological flora in an air-conditioned building with that in a naturally ventilated building, eight sets of measurements were made over a 1-year period. Concurrently with other environmental measurements, air samples were collected in each building, from three offices and from the outdoor air, using the Andersen single-stage sampler. Three different media were used to culture fungi, staphylococci and mesophilic bacteria. Multivariate analysis revealed a group of offices more contaminated than others, and a marked seasonal variation in fungal concentrations. A comparison of mean levels of microorganisms measured in the two buildings showed that the air microbial content was significantly higher and more variable in the naturally ventilated building than in the air-conditioned building. Moreover, in the naturally ventilated building, the interior fungal content was strongly dependent on the outdoor content, while in the air-conditioned building fungal concentrations remained constant despite significant variations measured outside. This was confirmed by a statistical comparison of the correlation coefficients between indoor and outdoor concentrations. No difference was observed regarding gaseous pollutants and temperature, but relative humidity was significantly higher in the air-conditioned building. The effect of HVAC was to prevent the intake of outdoor particles and to dilute the indoor concentrations. These results are consistent with the presence of high-efficiency filters and a steam humidifier in the HVAC system under study.

  19. Interaction of Plutonium with Diverse Materials in Moist Air and Nitrogen-Argon Atmospheres at Room Temperature

    SciTech Connect

    John M. Haschke; Raymond J. Martinez; Robert E. Pruner II; Barbara Martinez; Thomas H. Allen

    2001-04-01

    Chemical and radiolytic interactions of weapons-grade plutonium with metallic, inorganic, and hydrogenous materials in atmospheres containing moist air-argon mixtures have been characterized at room temperature from pressure-volume-temperature and mass spectrometric measurements of the gas phase. A reaction sequence controlled by kinetics and gas-phase composition is defined by correlating observed and known reaction rates. In all cases, O{sub 2} is eliminated first by the water-catalyzed Pu + O{sub 2} reaction and H{sub 2}O is then consumed by the Pu + H{sub 2}O reaction, producing a gas mixture of N{sub 2}, argon, and H{sub 2}. Hydrogen formed by the reaction of water and concurrent radiolysis of hydrogenous materials either reacts to form PuH{sub 2} or accumulates in the system. Accumulation of H{sub 2} is correlated with the presence of hydrogenous materials in liquid and volatile forms that are readily distributed over the plutonium surface. Areal rates of radiolytic H{sub 2} generation are determined and applied in showing that modest extents of H{sub 2} production are expected for hydrogenous solids if the contact area with plutonium is limited. The unpredictable nature of complex chemical systems is demonstrated by occurrence of the chloride-catalyzed Pu + H{sub 2}O reaction in some tests and hydride-catalyzed nitriding in another.

  20. Controllable Growth of Perovskite Films by Room-Temperature Air Exposure for Efficient Planar Heterojunction Photovoltaic Cells

    SciTech Connect

    Yang, Bin; Dyck, Ondrej; Poplawsky, Jonathan; Keum, Jong; Das, Sanjib; Puretzky, Alexander; Aytug, Tolga; Joshi, Pooran C.; Rouleau, Christopher M.; Duscher, Gerd; Geohegan, David B.; Xiao, Kai

    2015-12-01

    A two-step-solution-processing approach has been established to grow void-free perovskite films for low-cost and high-performance planar heterojunction photovoltaic devices. We generally applied a high-temperature thermal annealing treatment in order to drive the diffusion of CH3NH3I precursor molecules into the compact PbI2 layer to form perovskite films. But, thermal annealing for extended periods would lead to degraded device performance due to the defects generated by decomposition of perovskite into PbI2. In this work, we explored a controllable layer-by-layer spin-coating method to grow bilayer CH3NH3I/PbI2 films, and then drive the interdiffusion between PbI2 and CH3NH3I layers by a simple room-temperature-air-exposure for making well-oriented, highly-crystalline perovskite films without thermal annealing. This high degree of crystallinity resulted in a carrier diffusion length of ~ 800 nm and high device efficiency of 15.6%, which is comparable to the reported values from thermally-annealed perovskite films based counterparts. Finally, the simplicity and high device performance of this processing approach is highly promising for direct integration into industrial-scale device manufacture.

  1. Controllable Growth of Perovskite Films by Room-Temperature Air Exposure for Efficient Planar Heterojunction Photovoltaic Cells

    DOE PAGESBeta

    Yang, Bin; Dyck, Ondrej; Poplawsky, Jonathan; Keum, Jong; Das, Sanjib; Puretzky, Alexander; Aytug, Tolga; Joshi, Pooran C.; Rouleau, Christopher M.; Duscher, Gerd; et al

    2015-12-01

    A two-step-solution-processing approach has been established to grow void-free perovskite films for low-cost and high-performance planar heterojunction photovoltaic devices. We generally applied a high-temperature thermal annealing treatment in order to drive the diffusion of CH3NH3I precursor molecules into the compact PbI2 layer to form perovskite films. But, thermal annealing for extended periods would lead to degraded device performance due to the defects generated by decomposition of perovskite into PbI2. In this work, we explored a controllable layer-by-layer spin-coating method to grow bilayer CH3NH3I/PbI2 films, and then drive the interdiffusion between PbI2 and CH3NH3I layers by a simple room-temperature-air-exposure for makingmore » well-oriented, highly-crystalline perovskite films without thermal annealing. This high degree of crystallinity resulted in a carrier diffusion length of ~ 800 nm and high device efficiency of 15.6%, which is comparable to the reported values from thermally-annealed perovskite films based counterparts. Finally, the simplicity and high device performance of this processing approach is highly promising for direct integration into industrial-scale device manufacture.« less

  2. Analyses of an air conditioning system with entropy generation minimization and entransy theory

    NASA Astrophysics Data System (ADS)

    Yan-Qiu, Wu; Li, Cai; Hong-Juan, Wu

    2016-06-01

    In this paper, based on the generalized heat transfer law, an air conditioning system is analyzed with the entropy generation minimization and the entransy theory. Taking the coefficient of performance (denoted as COP) and heat flow rate Q out which is released into the room as the optimization objectives, we discuss the applicabilities of the entropy generation minimization and entransy theory to the optimizations. Five numerical cases are presented. Combining the numerical results and theoretical analyses, we can conclude that the optimization applicabilities of the two theories are conditional. If Q out is the optimization objective, larger entransy increase rate always leads to larger Q out, while smaller entropy generation rate does not. If we take COP as the optimization objective, neither the entropy generation minimization nor the concept of entransy increase is always applicable. Furthermore, we find that the concept of entransy dissipation is not applicable for the discussed cases. Project supported by the Youth Programs of Chongqing Three Gorges University, China (Grant No. 13QN18).

  3. Apparatus for supplying conditioned air at a substantially constant temperature and humidity

    NASA Technical Reports Server (NTRS)

    Obler, H. D. (Inventor)

    1980-01-01

    The apparatus includes a supply duct coupled to a source of supply air for carrying the supply air therethrough. A return duct is coupled to the supply duct for carrying return conditioned air therethrough. A temperature reducing device is coupled to the supply duct for decreasing the temperature of the supply and return conditioned air. A by-pass duct is coupled to the supply duct for selectively directing portions of the supply and return conditioned air around the temperature reducing device. Another by-pass duct is coupled to the return duct for selectively directing portions of the return conditioned air around the supply duct and the temperature reduction device. Controller devices selectively control the flow and amount of mixing of the supply and return conditioned air.

  4. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... conditioning test simulations. 86.162-03 Section 86.162-03 Protection of Environment ENVIRONMENTAL PROTECTION... alternative air conditioning test simulations. (a) Upon petition from a manufacturer or upon the Agency's own initiative, the Administrator will approve a simulation of the environmental cell for air conditioning...

  5. COMPOSITION CHANGES IN REFRIGERANT BLENDS FOR AUTOMOTIVE AIR CONDITIONING

    EPA Science Inventory

    Three refrigerant blends used to replace CFC-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in b...

  6. 83. DETAIL OF HONEYWELL AIRCONDITIONING CONTROLS IN SLC3E CONTROL ROOM ...

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

    83. DETAIL OF HONEYWELL AIR-CONDITIONING CONTROLS IN SLC-3E CONTROL ROOM - Vandenberg Air Force Base, Space Launch Complex 3, Launch Operations Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  7. Reaction of perfluoroalkylpolyethers (PFPE) with 440C steel in vacuum under sliding conditions at room temperature

    NASA Technical Reports Server (NTRS)

    Mori, Shigeyuki; Morales, Wilfredo

    1989-01-01

    Reactions of perfluoroalkylpolyethers (PFPE: Fomblin, Demnum and Krytox) were studied during the sliding contact of stainless steel specimens under ultrahigh vacuum conditions. All three fluids reacted with the steel specimens during sliding. Fomblin, which has acetal linkages, decomposed under the sliding conditions generating gaseous products, (COF2 and fluorinated carbons) which were detected by a quadrupole mass spectrometer. Gaseous products were not detected for the Demnum and Krytox fluids. The amount of gaseous products from Fomblin increased with increasing sliding speed. At the end of the sliding experiments, the wear scar and deposits on the specimens were examined by small spot size XPS. The oxide layer on the specimen surface was removed during sliding, and metal fluorides were formed on the worn surface. The surface of the wear scar and deposits were covered with adsorbed PFPE. Based on these results, it was concluded that the decomposition reaction on Fomblin was initiated by contacting the fluid with a fresh metal surface which was formed during sliding.

  8. Air pollution and hospital admissions for respiratory conditions in Rome, Italy.

    PubMed

    Fusco, D; Forastiere, F; Michelozzi, P; Spadea, T; Ostro, B; Arcà, M; Perucci, C A

    2001-06-01

    Most of the evidence regarding the association between particulate air pollution and emergency room visits or hospital admissions for respiratory conditions and asthma comes from the USA. European time-series analyses have suggested that gaseous air pollutants are important determinants of acute hospitalization for respiratory conditions, at least as important as particulate mass. The association between daily mean levels of suspended particles and gaseous pollutants (sulphur dioxide, nitrogen dioxide, carbon monoxide, ozone) was examined. The daily emergency hospital admissions for respiratory conditions in the metropolitan area of Rome during 1995-1997 were also recorded. Daily counts of hospital admissions for total respiratory conditions (43 admissions day(-1)), acute respiratory infections including pneumonia (18 day(-1)), chronic obstructive pulmonary disease (COPD) (13 day(-1)), and asthma (4.5 day(-1)) among residents of all ages and among children (0-14 yrs) were analysed. The generalized additive models included spline smooth functions of the day of study, mean temperature, mean humidity, influenza epidemics, and indicator variables for day of the week and holidays. Total respiratory admissions were significantly associated with same-day level of NO2 (2.5% increase per interquartile range (IQR) change, 22.3 microg x m(-3)) and CO (2.8% increase per IQR, 1.5 mg x m(-3)). No effect was found for particulate matter and SO2, whereas O3 was associated with admissions only among children (lag 1, 5.5% increase per IQR, 23.9 microg x m3). The effect of NO2 was stronger on acute respiratory infections (lag 0, 4.0% increase) and on asthma among children (lag 1, 10.7% increase). The admissions for all ages for asthma and COPD were associated only with same-day level of CO (5.5% and 4.3% increase, respectively). Multipollutant models confirmed the role of CO on all respiratory admissions, including asthma and COPD, and that of NO2 on acute respiratory infections

  9. Structure, optical, and electrical properties of indium tin oxide thin films prepared by sputtering at room temperature and annealed in air or nitrogen

    SciTech Connect

    Guillen, C.; Herrero, J.

    2007-04-01

    Indium tin oxide (ITO) thin films have been grown onto soda-lime glass substrates by sputtering at room temperature with various oxygen to argon partial pressure ratios. After deposition, the samples have been annealed at temperatures ranging from 100 to 500 degree sign C in nitrogen or in air. The structure, optical, and electrical characteristics of the ITO coatings have been analyzed as a function of the deposition and the annealing parameters by x-ray diffraction, spectrophotometry, and Hall effect measurements. It has been found that the as-grown amorphous layers crystallize in the cubic structure by heating above 200 degree sign C. Simultaneously, the visible optical transmittance increases and the electrical resistance decreases, in proportions that depend mainly on the sputtering conditions. The lowest resistivity values have been obtained by annealing at 400 degree sign C in nitrogen, where the highest carrier concentrations are achieved, related to oxygen vacancy creation. Some relationships between the analyzed properties have been established, showing the dependence of the cubic lattice distortion and the infrared optical characteristics on the carrier concentration.

  10. Working conditions in the engine department - A qualitative study among engine room personnel on board Swedish merchant ships.

    PubMed

    Lundh, Monica; Lützhöft, Margareta; Rydstedt, Leif; Dahlman, Joakim

    2011-01-01

    The specific problems associated with the work on board within the merchant fleet are well known and have over the years been a topic of discussion. The work conditions in the engine room (ER) are demanding due to, e.g. the thermal climate, noise and awkward working postures. The work in the engine control room (ECR) has over recent years undergone major changes, mainly due to the introduction of computers on board. In order to capture the impact these changes had implied, and also to investigate how the work situation has developed, a total of 20 engine officers and engine ratings were interviewed. The interviews were semi-structured and Grounded Theory was used for the data analysis. The aim of the present study was to describe how the engine crew perceive their work situation and working environment on board. Further, the aim was to identify areas for improvements which the engine crew consider especially important for a safe and effective work environment. The result of the study shows that the design of the ECR and ER is crucial for how different tasks are performed. Design which does not support operational procedures and how tasks are performed risk inducing inappropriate behaviour as the crew members' are compelled to find alternative ways to perform their tasks in order to get the job done. These types of behaviour can induce an increased risk of exposure to hazardous substances and the engine crew members becoming injured. PMID:20870214

  11. Ice storage rooftop retrofit for rooftop air conditioning

    SciTech Connect

    Tomlinson, J.J.; Jennings, L.W.

    1997-09-01

    A significant fraction of the floor space in commercial and federal buildings is cooled by single-package rooftop air conditioning units. These units are located on flat roofs and usually operate during the day under hot conditions. They are usually less energy efficient than a chiller system for building cooling. Several U.S. companies are developing systems that employ ice storage in conjunction with chillers to replace older, inefficient rooftop units for improved performance and minimal use of on-peak electricity. Although the low evaporator temperatures needed for ice making tend to reduce the efficiency of the chiller, the overall operating costs of the ice storage system may be lower than that of a packaged, conventional rooftop installation. One version of this concept, the Roofberg{reg_sign} System developed by the Calmac Corporation, was evaluated on a small building at Oak Ridge National Laboratory in Oak Ridge, Tennessee. The Roofberg system consists of a chiller, an ice storage tank, and one or more rooftop units whose evaporator coils have been adapted to use a glycol solution for cooling. The ice storage component decouples the cooling demand of the building from the operation of the chiller. Therefore, the chiller can operate at night (cooler, more efficient condensing temperatures) to meet a daytime cooling demand. This flexibility permits a smaller chiller to satisfy a larger peak cooling load. Further, the system can be operated to shift the cooling demand to off-peak hours when electricity from the utility is generated more efficiently and at lower cost. This Roofberg system was successfully installed last year on a small one-story office building in Oak Ridge and is currently being operated to cool the building. The building and system were sufficiently instrumented to allow a determination of the performance and efficiency of the Roofberg system. Although the energy efficiency of a simulated Roofberg storage/chiller concept operating in the

  12. 32 CFR 855.7 - Conditions for use of Air Force airfields.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 6 2013-07-01 2013-07-01 false Conditions for use of Air Force airfields. 855.7 Section 855.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits §...

  13. 32 CFR 855.7 - Conditions for use of Air Force airfields.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 6 2012-07-01 2012-07-01 false Conditions for use of Air Force airfields. 855.7 Section 855.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits §...

  14. 32 CFR 855.7 - Conditions for use of Air Force airfields.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 6 2014-07-01 2014-07-01 false Conditions for use of Air Force airfields. 855.7 Section 855.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits §...

  15. 32 CFR 855.7 - Conditions for use of Air Force airfields.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 6 2010-07-01 2010-07-01 false Conditions for use of Air Force airfields. 855.7 Section 855.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits §...

  16. 32 CFR 855.7 - Conditions for use of Air Force airfields.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Conditions for use of Air Force airfields. 855.7 Section 855.7 National Defense Department of Defense (Continued) DEPARTMENT OF THE AIR FORCE AIRCRAFT CIVIL AIRCRAFT USE OF UNITED STATES AIR FORCE AIRFIELDS Civil Aircraft Landing Permits §...

  17. Fine Particulate Air Pollution and Hospital Emergency Room Visits for Respiratory Disease in Urban Areas in Beijing, China, in 2013

    PubMed Central

    Wang, Shuo; Wang, Chao; Huang, Fangfang; Gao, Qi; Wu, Lijuan; Tao, Lixin; Guo, Jin; Wang, Wei; Guo, Xiuhua

    2016-01-01

    Background Heavy fine particulate matter (PM2.5) air pollution occurs frequently in China. However, epidemiological research on the association between short-term exposure to PM2.5 pollution and respiratory disease morbidity is still limited. This study aimed to explore the association between PM2.5 pollution and hospital emergency room visits (ERV) for total and cause-specific respiratory diseases in urban areas in Beijing. Methods Daily counts of respiratory ERV from Jan 1 to Dec 31, 2013, were obtained from ten general hospitals located in urban areas in Beijing. Concurrently, data on PM2.5 were collected from the Beijing Environmental Protection Bureau, including 17 ambient air quality monitoring stations. A generalized-additive model was used to explore the respiratory effects of PM2.5, after controlling for confounding variables. Subgroup analyses were also conducted by age and gender. Results A total of 92,464 respiratory emergency visits were recorded during the study period. The mean daily PM2.5 concentration was 102.1±73.6 μg/m3. Every 10 μg/m3 increase in PM2.5 concentration at lag0 was associated with an increase in ERV, as follows: 0.23% for total respiratory disease (95% confidence interval [CI]: 0.11%-0.34%), 0.19% for upper respiratory tract infection (URTI) (95%CI: 0.04%-0.35%), 0.34% for lower respiratory tract infection (LRTI) (95%CI: 0.14%-0.53%) and 1.46% for acute exacerbation of chronic obstructive pulmonary disease (AECOPD) (95%CI: 0.13%-2.79%). The strongest association was identified between AECOPD and PM2.5 concentration at lag0-3 (3.15%, 95%CI: 1.39%-4.91%). The estimated effects were robust after adjusting for SO2, O3, CO and NO2. Females and people 60 years of age and older demonstrated a higher risk of respiratory disease after PM2.5 exposure. Conclusion PM2.5 was significantly associated with respiratory ERV, particularly for URTI, LRTI and AECOPD in Beijing. The susceptibility to PM2.5 pollution varied by gender and age. PMID

  18. Comprehensive Assessment of Influence of Enhanced Component in Vapor Compression Air Conditioning System on Performance

    NASA Astrophysics Data System (ADS)

    Shinomiya, Naruaki; Nishimura, Nobuya; Iyota, Hiroyuki

    System performance prediction model for air-cooled air conditioner has been developed, and influences of Grooved tubes on performance of air conditioners with R410A were quantitatively investigated. Calculated results with simulation model correspond approximately to measured results by the authors and other researchers. After that, performances of air conditioners with grooved tubes were predicted. Results show that condensation heat transfer coefficients decrease with the rise of air conditioning load rate, and boiling heat transfer coefficients increase with the rise of air conditioning load rate. On the other hand, pressure drops increase 1.2-1.4 times in evaporator. Then, COPs of air conditioners with the grooved tube are 1.16 times higher than COP of air-conditioners with the smooth tube.

  19. Performance of a photovoltaically powered air-conditioning system

    SciTech Connect

    Kern, Jr, E. C.; Millner, A. R.

    1980-01-01

    A vapor-compression air conditioner coupled directly to a photovoltaic array is discussed. Previous analyses of such a system are reviewed, and a development system designed to test the concept is described. Preliminary experiments indicate that the performance of this initial system falls considerably short of analytic expectations.

  20. Retrofitting Air Conditioning and Duct Systems in Hot, Dry Climates

    SciTech Connect

    Shapiro, Carl; Aldrich, Robb; Arena, Lois

    2012-07-01

    This technical report describes CARB's work with Clark County Community Resources Division in Las Vegas, Nevada, to optimize procedures for upgrading cooling systems on existing homes in the area to implement health, safety, and energy improvements. Detailed monitoring of five AC systems showed that three of the five systems met or exceeded air flow rate goals.

  1. Operator's Manual, Boiler Room Operations and Maintenance. Supplement A, Air Pollution Training Institute Self-Instructional Course SI-466.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Research Triangle Park, NC. Air Pollution Training Inst.

    This Operator's Manual is a supplement to a self-instructional course prepared for the United States Environmental Protection Agency. This publication is the Boiler Room Handbook for operating and maintaining the boiler and the boiler room. As the student completes this handbook, he is putting together a manual for running his own boiler. The…

  2. Imaging human brown adipose tissue under room temperature conditions with 11C-MRB, a selective norepinephrine transporter PET ligand

    PubMed Central

    Hwang, Janice J.; Yeckel, Catherine W.; Gallezot, Jean-Dominique; Aguiar, Renata Belfort-De; Ersahin, Devrim; Gao, Hong; Kapinos, Michael; Nabulsi, Nabeel; Huang, Yiyun; Cheng, David; Carson, Richard E.; Sherwin, Robert; Ding, Yu-Shin

    2015-01-01

    Introduction Brown adipose tissue (BAT) plays a critical role in adaptive thermogenesis and is tightly regulated by the sympathetic nervous system (SNS). However, current BAT imaging modalities require cold stimulation and are often unreliable to detect BAT in the basal state, at room temperature (RT). We have shown previously that BAT can be detected in rodents under both RT and cold conditions with 11C-MRB ((S,S)-11C-O-methylreboxetine), a highly selective ligand for the norepinephrine transporter (NET). Here, we evaluate this novel approach for BAT detection in adult humans under RT conditions. Methods Ten healthy, Caucasian subjects (5 M: age 24.6±2.6, BMI 21.6±2.7 kg/m2; 5 F: age 25.4±2.1, BMI 22.1±1.0 kg/m2) underwent 11C-MRB PET-CT imaging for cervical/supraclavicular BAT under RT and cold-stimulated conditions (RPCM Cool vest; enthalpy 15°C) compared to 18F-FDG PET-CT imaging. Uptake of 11C-MRB, was quantified as the distribution volume ratio (DVR) using the occipital cortex as a low NET density reference region. Total body fat and lean body mass were assessed via bioelectrical impedance analysis. Results As expected, 18F-FDG uptake in BAT was difficult to identify at RT but easily detected with cold stimulation (p=0.01). In contrast, BAT 11C-MRB uptake (also normalized for muscle) was equally evident under both RT and cold conditions (BAT DVR: RT 1.0±0.3 vs. cold 1.1±0.3, p=0.31; BAT/muscle DVR: RT 2.3±0.7 vs. cold 2.5±0.5, p=0.61). Importantly, BAT DVR and BAT/muscle DVR of 11C-MRB at RT correlated positively with core body temperature (r=0.76, p=0.05 and r=0.92, p=0.004, respectively), a relationship not observed with 18F-FDG (p=0.63). Furthermore, there were gender differences in 11C-MRB uptake in response to cold (p=0.03), which reflected significant differences in the change in 11C-MRB as a function of both body composition and body temperature. Conclusions Unlike 18F-FDG, the uptake of 11C-MRB in BAT offers a unique opportunity to

  3. Simulation of air gap vibration on aerostatic bearing under flow/structure coupled conditions

    NASA Astrophysics Data System (ADS)

    Wang, Qian; Wu, Jianjin; Li, Dongsheng

    2008-10-01

    The vibration of aerostatic bearing air gap is one of the main factors, which restricts the precision of nano-processing and nano-measurement. Finite volume method was employed to obtain the air gap steady flow of different air gap thicknesses for the demonstration of vibrations under flow/structure coupled conditions. The unsteady flow of air gap was analyzed numerically by using the air gap flow & boundary movement control equations to get the pressure distribution on the slide surface and the amplitude of air gap for further study on the self-excited vibration of aerostatic bearings. Numerical analyses show that the highest aerostatic bearing amplitude is relative to the difference between load capacity and gravity at the initial moment as air gap rises, and the final air gap thickness has nothing to do with the initial air gap thickness. The results presented a new analytic demonstration for the research on the reduction of aerostatic bearing vibration.

  4. The influence of air-conditioning on street temperatures in the city of Paris

    NASA Astrophysics Data System (ADS)

    de Munck, C. S.; Pigeon, G.; Masson, V.; Marchadier, C.; Meunier, F.; Tréméac, B.; Merchat, M.

    2010-12-01

    A consequence of urban heat islands in summer is the increased use of air-conditioning during extreme heat events : the use of air-conditioning systems, while cooling the inside of buildings releases waste heat (as latent and sensible heat) in the lower part of the urban atmosphere, hence potentially increasing air street temperatures where the heat is released. This may lead locally to a further increase in air street temperatures, therefore increasing the air cooling demand, while at the same time lowering the efficiency of air-conditioning units. A coupled model consisting of a meso-scale meteorological model (MESO-NH) and an urban energy balance model (TEB) has been implemented with an air-conditioning module and used in combination to real spatialised datasets to understand and quantify potential increases in temperature due to air-conditioning heat releases for the city of Paris . In a first instance, the current types of air-conditioning systems co-existing in the city were simulated (underground chilled water network, wet cooling towers and individual air-conditioning units) to study the effects of latent and sensible heat releases on street temperatures. In a third instance, 2 scenarios were tested to characterise the impacts of likely future trends in air-conditioning equipment in the city : a first scenario for which current heat releases were converted to sensible heat, and a second based on 2030s projections of air-conditioning equipment at the scale of the city. All the scenarios showed an increase in street temperature which, as expected, was greater at night time than day time. For the first two scenarios, this increase in street temperatures was localised at or near the sources of air-conditioner heat releases, while the 2030s air-conditioning scenario impacted wider zones in the city. The amplitude of the increase in temperature varied from 0,25°C to 1°C for the air-conditioning current state, between 0,25°C and 2°C for the sensible heat

  5. Large Eddy Simulation of Air Escape through a Hospital Isolation Room Single Hinged Doorway--Validation by Using Tracer Gases and Simulated Smoke Videos.

    PubMed

    Saarinen, Pekka E; Kalliomäki, Petri; Tang, Julian W; Koskela, Hannu

    2015-01-01

    The use of hospital isolation rooms has increased considerably in recent years due to the worldwide outbreaks of various emerging infectious diseases. However, the passage of staff through isolation room doors is suspected to be a cause of containment failure, especially in case of hinged doors. It is therefore important to minimize inadvertent contaminant airflow leakage across the doorway during such movements. To this end, it is essential to investigate the behavior of such airflows, especially the overall volume of air that can potentially leak across the doorway during door-opening and human passage. Experimental measurements using full-scale mock-ups are expensive and labour intensive. A useful alternative approach is the application of Computational Fluid Dynamics (CFD) modelling using a time-resolved Large Eddy Simulation (LES) method. In this study simulated air flow patterns are qualitatively compared with experimental ones, and the simulated total volume of air that escapes is compared with the experimentally measured volume. It is shown that the LES method is able to reproduce, at room scale, the complex transient airflows generated during door-opening/closing motions and the passage of a human figure through the doorway between two rooms. This was a basic test case that was performed in an isothermal environment without ventilation. However, the advantage of the CFD approach is that the addition of ventilation airflows and a temperature difference between the rooms is, in principle, a relatively simple task. A standard method to observe flow structures is dosing smoke into the flow. In this paper we introduce graphical methods to simulate smoke experiments by LES, making it very easy to compare the CFD simulation to the experiments. The results demonstrate that the transient CFD simulation is a promising tool to compare different isolation room scenarios without the need to construct full-scale experimental models. The CFD model is able to reproduce

  6. Large Eddy Simulation of Air Escape through a Hospital Isolation Room Single Hinged Doorway—Validation by Using Tracer Gases and Simulated Smoke Videos

    PubMed Central

    Saarinen, Pekka E.; Kalliomäki, Petri; Tang, Julian W.; Koskela, Hannu

    2015-01-01

    The use of hospital isolation rooms has increased considerably in recent years due to the worldwide outbreaks of various emerging infectious diseases. However, the passage of staff through isolation room doors is suspected to be a cause of containment failure, especially in case of hinged doors. It is therefore important to minimize inadvertent contaminant airflow leakage across the doorway during such movements. To this end, it is essential to investigate the behavior of such airflows, especially the overall volume of air that can potentially leak across the doorway during door-opening and human passage. Experimental measurements using full-scale mock-ups are expensive and labour intensive. A useful alternative approach is the application of Computational Fluid Dynamics (CFD) modelling using a time-resolved Large Eddy Simulation (LES) method. In this study simulated air flow patterns are qualitatively compared with experimental ones, and the simulated total volume of air that escapes is compared with the experimentally measured volume. It is shown that the LES method is able to reproduce, at room scale, the complex transient airflows generated during door-opening/closing motions and the passage of a human figure through the doorway between two rooms. This was a basic test case that was performed in an isothermal environment without ventilation. However, the advantage of the CFD approach is that the addition of ventilation airflows and a temperature difference between the rooms is, in principle, a relatively simple task. A standard method to observe flow structures is dosing smoke into the flow. In this paper we introduce graphical methods to simulate smoke experiments by LES, making it very easy to compare the CFD simulation to the experiments. The results demonstrate that the transient CFD simulation is a promising tool to compare different isolation room scenarios without the need to construct full-scale experimental models. The CFD model is able to reproduce

  7. Indoor air pollution due to tobacco smoke under real conditions. Preliminary results.

    PubMed

    Klus, H; Begutter, H; Nowak, A; Pinterits, G; Ultsch, I; Wihlidal, H

    1985-08-01

    A short review exploring the generation and composition of tobacco smoke is given. Experimental arrangements used to record sidestream smoke are critically discussed. Data from own experiments in a tobacco smoke polluted office room were presented and discussed. These data include nicotine, ammonia, formaldehyde, acetaldehyde, hydrogen cyanide, CO, NO and NO2. First results about the diameter of the particles in the smoke polluted room were also given. By the aid of the RINGOLD's equation the COHB content on basis of the CO-values of exhaled breath of active and passive smokers were determined. Data about the nitrosamine content in the air of the room during the smoke tests were also given and discussed. PMID:3836513

  8. The Effect of Air-Conditioning on Student and Teacher Performance.

    ERIC Educational Resources Information Center

    Phoenix Union High School District, AZ. Dept. of Research and Planning.

    The literature is reviewed to see if research shows a relationship between student and teacher performance and air conditioning of classrooms. The benefits of air conditioning in promoting learning are substantiated by studies that are summarized but not cited. The relationship of the report to the Phoenix Union High School System Advisory…

  9. Automotive Air Conditioning and Heating; Automotive Mechanics (Advanced): 9047.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This document presents an outline for a 135-hour course designed to provide the student with all the foundations necessary to become employable in the automotive air conditioning and heating trade. The course of study includes an orientation to the world of work, the elementary physics of air conditioning and heating, and laboratory experiments…

  10. Criterion-Referenced Test (CRT) Items for Air Conditioning, Heating and Refrigeration.

    ERIC Educational Resources Information Center

    Davis, Diane, Ed.

    These criterion-referenced test (CRT) items for air conditioning, heating, and refrigeration are keyed to the Missouri Air Conditioning, Heating, and Refrigeration Competency Profile. The items are designed to work with both the Vocational Instructional Management System and Vocational Administrative Management System. For word processing and…

  11. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Package, Special Form, and LSA-III Tests 2 § 71.74 Accident conditions for air transport...

  12. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Package, Special Form, and LSA-III Tests 2 § 71.74 Accident conditions for air transport of plutonium. (a) Test conditions—Sequence...

  13. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Package, Special Form, and LSA-III Tests 2 § 71.74 Accident conditions for air transport of plutonium. (a) Test conditions—Sequence...

  14. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Package, Special Form, and LSA-III Tests 2 § 71.74 Accident conditions for air transport of plutonium. (a) Test conditions—Sequence...

  15. 10 CFR 71.74 - Accident conditions for air transport of plutonium.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Accident conditions for air transport of plutonium. 71.74 Section 71.74 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) PACKAGING AND TRANSPORTATION OF RADIOACTIVE MATERIAL Package, Special Form, and LSA-III Tests 2 § 71.74 Accident conditions for air transport of plutonium. (a) Test conditions—Sequence...

  16. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... environmental cell test data for the range of vehicles to be covered by the simulation including items such as the tailpipe emissions, air conditioning compressor load, and fuel economy. (2) For any...

  17. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... determine a refrigerant leakage rate in grams per year from vehicle-based air conditioning units. The... using the following equation: Grams/YRTOT = Grams/YRRP + Grams/YRSP + Grams/YRFH + Grams/YRMC + Grams/YRC Where: Grams/YRTOT = Total air conditioning system emission rate in grams per year and rounded...

  18. Supporting Air-Conditioning Controller Design Using Evolutionary Computation

    NASA Astrophysics Data System (ADS)

    Kojima, Kazuyuki; Watanuki, Keiichi

    In recent years, as part of the remarkable development of electronic techniques, electronic control has been applied to various systems. Many sensors and actuators have been implemented into those systems, and energy efficiency and performance have been greatly improved. However, these systems have been complicated, and much time has been required to develop system controllers. In this paper, a method of automatic controller design for those systems is described. In order to automate the design of an electronic controller, an evolutionary hardware is applied. First, the framework for applying the genetic algorithm to the automation of controller design is described. In particular, the coding of a chromosome is shown in detail. Then, how to make a fitness function is represented, with an air conditioner as an example, and the controller of the air conditioner is developed automatically using our proposed framework. Finally, an evolutionary simulation is performed to confirm our framework.

  19. Reduction of air ion mobility to standard conditions

    NASA Astrophysics Data System (ADS)

    Tammet, H.

    1998-06-01

    The Langevin rule of the reduction of air ion mobility is adequate in case of zero-size ions. An alternative is the Stokes-Millikan equation that is adequate in the limit of macroscopic charged particles. The temperature variation of air ion mobility predicted by the Stokes-Millikan equation radically contradicts the Langevin rule. The temperature and pressure variation of air ion mobility is examined by using a new semiempirical model that describes the transition from the kinetic theory to the Stokes-Millikan equation. The model is valid in full mobility range. It allows to calculate at first the size of an ion according to the measured mobility and then the standard mobility according to the size. The ascent of the temperature-mobility curve on a logarithmic chart approaches the Langevin value of 1 only at very high mobilities not found in the atmosphere. The value of the ascent is 0.6 in the case of small ions of the mobility of 1.5 cm2 V-1 s-1 which brings about a considerable error when using the Langevin rule. It is recommended to store the natural values of the mobility in databases together with the values of temperature and pressure and to definitely indicate the method when the reduced mobilities are presented in publications.

  20. Reducing indoor air pollution by air conditioning is associated with improvements in cardiovascular health among the general population.

    PubMed

    Lin, Lian-Yu; Chuang, Hsiao-Chi; Liu, I-Jung; Chen, Hua-Wei; Chuang, Kai-Jen

    2013-10-01

    Indoor air pollution is associated with cardiovascular effects, however, little is known about the effects of improving indoor air quality on cardiovascular health. The aim of this study was to explore whether improving indoor air quality through air conditioning can improve cardiovascular health in human subjects. We recruited a panel of 300 healthy subjects from Taipei, aged 20 and over, to participate in six home visits each, to measure a variety of cardiovascular endpoints, including high sensitivity-C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG), fibrinogen in plasma and heart rate variability (HRV). Indoor particles and total volatile organic compounds (VOCs) were measured simultaneously at the participant's home during each visit. Three exposure conditions were investigated in this study: participants were requested to keep their windows open during the first two visits, close their windows during the next two visits, and close the windows and turn on their air conditioners during the last two visits. We used linear mixed-effects models to associate the cardiovascular endpoints with individual indoor air pollutants. The results showed that increases in hs-CRP, 8-OHdG and fibrinogen, and decreases in HRV indices were associated with increased levels of indoor particles and total VOCs in single-pollutant and two-pollutant models. The effects of indoor particles and total VOCs on cardiovascular endpoints were greatest during visits with the windows open. During visits with the air conditioners turned on, no significant changes in cardiovascular endpoints were observed. In conclusion, indoor air pollution is associated with inflammation, oxidative stress, blood coagulation and autonomic dysfunction. Reductions in indoor air pollution and subsequent improvements in cardiovascular health can be achieved by closing windows and turning on air conditioners at home. PMID:23803502

  1. Low-Flow Liquid Desiccant Air Conditioning: General Guidance and Site Considerations

    SciTech Connect

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.

    2014-09-01

    Dehumidification or latent cooling in buildings is an area of growing interest that has been identified as needing more research and improved technologies for higher performance. Heating, ventilating, and air-conditioning (HVAC) systems typically expend excessive energy by using overcool-and-reheat strategies to dehumidify buildings. These systems first overcool ventilation air to remove moisture and then reheat the air to meet comfort requirements. Another common strategy incorporates solid desiccant rotors that remove moisture from the air more efficiently; however, these systems increase fan energy consumption because of the high airside pressure drop of solid desiccant rotors and can add heat of absorption to the ventilation air. Alternatively, liquid desiccant air-conditioning (LDAC) technology provides an innovative dehumidification solution that: (1) eliminates the need for overcooling and reheating from traditional cooling systems; and (2) avoids the increased fan energy and air heating from solid desiccant rotor systems.

  2. Combustion of Gaseous Fuels with High Temperature Air in Normal- and Micro-gravity Conditions

    NASA Technical Reports Server (NTRS)

    Wang, Y.; Gupta, A. K.

    2001-01-01

    The objective of this study is determine the effect of air preheat temperature on flame characteristics in normal and microgravity conditions. We have obtained qualitative (global flame features) and some quantitative information on the features of flames using high temperature combustion air under normal gravity conditions with propane and methane as the fuels. This data will be compared with the data under microgravity conditions. The specific focus under normal gravity conditions has been on determining the global flame features as well as the spatial distribution of OH, CH, and C2 from flames using high temperature combustion air at different equivalence ratio.

  3. Avoiding 100 new power plants by increasing efficiency of room air conditioners in India: opportunities and challenges

    SciTech Connect

    Phadke, Amol; Abhyankar, Nikit; Shah, Nihar

    2013-10-15

    Electricity demand for room ACs is growing very rapidly in emerging economies such as India. We estimate the electricity demand from room ACs in 2030 in India considering factors such as weather and income growth using market data on penetration of ACs in different income classes and climatic regions. We discuss the status of the current standards, labels, and incentive programs to improve the efficiency of room ACs in these markets and assess the potential for further large improvements in efficiency and find that efficiency can be improved by over 40% cost effectively. The total potential energy savings from Room AC efficiency improvement in India using the best available technology will reach over 118 TWh in 2030; potential peak demand saving is found to be 60 GW by 2030. This is equivalent to avoiding 120 new coal fired power plants of 500 MW each. We discuss policy options to complement, expand and improve the ongoing programs to capture this large potential.

  4. Avoiding 100 New Power Plants by Increasing Efficiency of Room Air Conditioners in India: Opportunities and Challenges

    SciTech Connect

    Phadke, Amol; Abhyankar, Nikit; Shah, Nihar

    2014-06-19

    Electricity demand for room ACs is growing very rapidly in emerging economies such as India. We estimate the electricity demand from room ACs in 2030 in India considering factors such as weather and income growth using market data on penetration of ACs in different income classes and climatic regions. We discuss the status of the current standards, labels, and incentive programs to improve the efficiency of room ACs in these markets and assess the potential for further large improvements in efficiency and find that efficiency can be improved by over 40percent cost effectively. The total potential energy savings from Room AC efficiency improvement in India using the best available technology will reach over 118 TWh in 2030; potential peak demand saving is found to be 60 GW by 2030. This is equivalent to avoiding 120 new coal fired power plants of 500 MW each. We discuss policy options to complement, expand and improve the ongoing programs to capture this large potential.

  5. [Working ability between air and trimix breathing gas under 8 ATA air condition].

    PubMed

    Shibayama, M; Kosugi, S; Mohri, M; Yamamura, I; Oda, S; Kimura, A; Takeuchi, J; Mano, Y

    1990-04-01

    Pneumatic caisson work in Japan has come into operation since 1924. Afterward, this technique of compressed air work has been widely utilized in the construction of foundation basements, shafts of the bottom tunnel shields for subway and so forth. While using this technique of compressed air work means that workers have to be exposed to hyperbaric environment, this technique has risks of not only decompression sickness (DCS) but also toxicity of poisonous gas and/or oxygen deficiency. However, this technique is independent of city construction work and the operation of compressed air work higher than 5ATA (4.0 kg/cm2G) is actually been planning recently. Accordingly unmanned caisson work is considered as a better technique for such higher pressurized work, even though workers must enter into hyperbaric working fields for maintenance or repair of unmanned operated machinery and materials. This research is to establish the safe work under hyperbaric air environment at 8ATA. PMID:2400467

  6. Dynamics of electrical double layer formation in room-temperature ionic liquids under constant-current charging conditions

    SciTech Connect

    Jiang, Xikai; Huang, Jingsong; Zhao, Hui; Sumpter, Bobby G; Qiao, Rui

    2014-01-01

    We report detailed simulation results on the formation dynamics of an electrical double layer (EDL) inside an electrochemical cell featuring room-temperature ionic liquids (RTILs) enclosed between two planar electrodes. Under relatively small charging currents, the evolution of cell potential during charging can be suitably predicted by the Landau-Ginzburg-type continuum model proposed recently (M. Z. Bazant, B. D. Storey, and A. A. Kornyshev, Phys. Rev. Lett., 106, 046102, 2011). Under very large charging currents, the cell potential shows pronounced oscillation during the initial stage of charging, a feature not captured by the continuum model. Such oscillation originates from the sequential growth of the ionic space charge layers near the electrode surface, allowing the evolution of EDLs in RTILs with time, an atomistic process difficult to visualize experimentally, to be studied by analyzing the cell potential under constant current charging conditions. While the continuum model cannot predict the potential oscillation under such far-from-equilibrium charging conditions, it can nevertheless qualitatively capture the growth of cell potential during the later stage of charging. Improving the continuum model by introducing frequency-dependent dielectric constant and density-dependent ion diffusion coefficients may help to further extend the applicability of the model. Keywords: ionic

  7. Dynamics of electrical double layer formation in room-temperature ionic liquids under constant-current charging conditions.

    PubMed

    Jiang, Xikai; Huang, Jingsong; Zhao, Hui; Sumpter, Bobby G; Qiao, Rui

    2014-07-16

    We report detailed simulation results on the formation dynamics of an electrical double layer (EDL) inside an electrochemical cell featuring room-temperature ionic liquids (RTILs) enclosed between two planar electrodes. Under relatively small charging currents, the evolution of cell potential from molecular dynamics (MD) simulations during charging can be suitably predicted by the Landau-Ginzburg-type continuum model proposed recently (Bazant et al 2011 Phys. Rev. Lett. 106 046102). Under very large charging currents, the cell potential from MD simulations shows pronounced oscillation during the initial stage of charging, a feature not captured by the continuum model. Such oscillation originates from the sequential growth of the ionic space charge layers near the electrode surface. This allows the evolution of EDLs in RTILs with time, an atomistic process difficult to visualize experimentally, to be studied by analyzing the cell potential under constant-current charging conditions. While the continuum model cannot predict the potential oscillation under such far-from-equilibrium charging conditions, it can nevertheless qualitatively capture the growth of cell potential during the later stage of charging. Improving the continuum model by introducing frequency-dependent dielectric constant and density-dependent ion diffusion coefficients may help to further extend the applicability of the model. The evolution of ion density profiles is also compared between the MD and the continuum model, showing good agreement. PMID:24919471

  8. Buoyancy driven acceleration in a hospital operating room indoor environment

    NASA Astrophysics Data System (ADS)

    McNeill, James; Hertzberg, Jean; Zhai, John

    2011-11-01

    In hospital operating rooms, centrally located non-isothermal ceiling jets provide sterile air for protecting the surgical site from infectious particles in the room air as well as room cooling. Modern operating rooms are requiring larger temperature differences to accommodate increasing cooling loads for heat gains from medical equipment. This trend may lead to significant changes in the room air distribution patterns that may sacrifice the sterile air field across the surgical table. Quantitative flow visualization experiments using laser sheet illumination and RANS modeling of the indoor environment were conducted to demonstrate the impact of the indoor environment thermal conditions on the room air distribution. The angle of the jet shear layer was studied as function of the area of the vena contracta of the jet, which is in turn dependent upon the Archimedes number of the jet. Increases in the buoyancy forces cause greater air velocities in the vicinity of the surgical site increasing the likelihood of deposition of contaminants in the flow field. The outcome of this study shows the Archimedes number should be used as the design parameter for hospital operating room air distribution in order to maintain a proper supply air jet for covering the sterile region. This work is supported by ASHRAE.

  9. Commander's conference room (room 202), closet and hallway to bathroom ...

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

    Commander's conference room (room 202), closet and hallway to bathroom and bedroom, leading to conference room 211. Viewing windows look down on the display area. View to north - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  10. Composition changes in refrigerant blends for automotive air conditioning

    SciTech Connect

    Jetter, J.J.; Delafield, F.R.; Ng, A.S.; Ratanaphruks, K.; Tufts, M.W.

    1999-07-01

    Three refrigerant blends used to replace the chlorofluorocarbon R-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in blend compositions caused no significant changes in refrigeration capacities. However, when recommended procedures were not followed, changes in compositions were relatively large. The amount of change in composition and the resulting effect on performance varied among the three refrigerant blends that were tested. Of the three blends, a quaternary blend containing hydrochlorofluorocarbon R-22 had the greatest changes in composition, while a binary blend containing hydrofluorocarbon R-134a had the smallest changes in composition.

  11. Air Conditioning Stall Phenomenon Testing, Model Development, and Simulation

    SciTech Connect

    Irminger, Philip; Rizy, D Tom; Li, Huijuan; Smith, Travis; Rice, C Keith; Li, Fangxing; Adhikari, Sarina

    2012-01-01

    Electric distribution systems are experiencing power quality issues of extended reduced voltage due to fault-induced delayed voltage recovery (FIDVR). FIDVR occurs in part because modern air conditioner (A/C) and heat pump compressor motors are much more susceptible to stalling during a voltage sag or dip such as a sub-transmission fault. They are more susceptible than older A/C compressor motors due to the low inertia of these newer and more energy efficient motors. There is a concern that these local reduced voltage events on the distribution system will become more frequent and prevalent and will combine over larger areas and challenge transmission system voltage and ultimately power grid reliability. The Distributed Energy Communications and Controls (DECC) Laboratory at Oak Ridge National Laboratory (ORNL) has been employed to (1) test, (2) characterize and (3) model the A/C stall phenomenon.

  12. Alternate working fluids for solar air conditioning applications

    NASA Technical Reports Server (NTRS)

    Evans, R. D.; Beck, J. K.

    1978-01-01

    An experimental investigation of sixteen different refrigerant-absorbent fluid pairs has been carried out in order to determine their suitability as the working fluid in a solar-powered absorption cycle air conditioner. The criteria used in the initial selection of a refrigerant-absorbent pair included: high affinity (large negative deviation from Raoult's Law), high solubility, low specific heat, low viscosity, stability, corrosive properties, safety, and cost. For practical solar considerations of a fluid pair, refrigerants were selected with low boiling points whereas absorbent fluids were selected with a boiling point considerably above that of the refrigerant. Additional restrictions are determined by the operating temperatures of the absorber and the generator; these temperatures were specified as 100 F (39 C) and 170 F (77 C). Data are presented for a few selected pressures at the specified absorber and generator temperatures.

  13. Impaired Air Conditioning within the Nasal Cavity in Flat-Faced Homo.

    PubMed

    Nishimura, Takeshi; Mori, Futoshi; Hanida, Sho; Kumahata, Kiyoshi; Ishikawa, Shigeru; Samarat, Kaouthar; Miyabe-Nishiwaki, Takako; Hayashi, Misato; Tomonaga, Masaki; Suzuki, Juri; Matsuzawa, Tetsuro; Matsuzawa, Teruo

    2016-03-01

    We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD) with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved "Out of Africa" to explore the more severe climates of

  14. Impaired Air Conditioning within the Nasal Cavity in Flat-Faced Homo

    PubMed Central

    Nishimura, Takeshi; Mori, Futoshi; Hanida, Sho; Kumahata, Kiyoshi; Ishikawa, Shigeru; Samarat, Kaouthar; Miyabe-Nishiwaki, Takako; Hayashi, Misato; Tomonaga, Masaki; Suzuki, Juri; Matsuzawa, Tetsuro; Matsuzawa, Teruo

    2016-01-01

    We are flat-faced hominins with an external nose that protrudes from the face. This feature was derived in the genus Homo, along with facial flattening and reorientation to form a high nasal cavity. The nasal passage conditions the inhaled air in terms of temperature and humidity to match the conditions required in the lung, and its anatomical variation is believed to be evolutionarily sensitive to the ambient atmospheric conditions of a given habitat. In this study, we used computational fluid dynamics (CFD) with three-dimensional topology models of the nasal passage under the same simulation conditions, to investigate air-conditioning performance in humans, chimpanzees, and macaques. The CFD simulation showed a horizontal straight flow of inhaled air in chimpanzees and macaques, contrasting with the upward and curved flow in humans. The inhaled air is conditioned poorly in humans compared with nonhuman primates. Virtual modifications to the human external nose topology, in which the nasal vestibule and valve are modified to resemble those of chimpanzees, change the airflow to be horizontal, but have little influence on the air-conditioning performance in humans. These findings suggest that morphological variation of the nasal passage topology was only weakly sensitive to the ambient atmosphere conditions; rather, the high nasal cavity in humans was formed simply by evolutionary facial reorganization in the divergence of Homo from the other hominin lineages, impairing the air-conditioning performance. Even though the inhaled air is not adjusted well within the nasal cavity in humans, it can be fully conditioned subsequently in the pharyngeal cavity, which is lengthened in the flat-faced Homo. Thus, the air-conditioning faculty in the nasal passages was probably impaired in early Homo members, although they have survived successfully under the fluctuating climate of the Plio-Pleistocene, and then they moved “Out of Africa” to explore the more severe climates of

  15. Desiccant Enhanced Evaporative Air-Conditioning (DEVap): Evaluation of a New Concept in Ultra Efficient Air Conditioning

    SciTech Connect

    Kozubal, E.; Woods, J.; Burch, J.; Boranian, A.; Merrigan, T.

    2011-01-01

    NREL has developed the novel concept of a desiccant enhanced evaporative air conditioner (DEVap) with the objective of combining the benefits of liquid desiccant and evaporative cooling technologies into an innovative 'cooling core.' Liquid desiccant technologies have extraordinary dehumidification potential, but require an efficient cooling sink. DEVap's thermodynamic potential overcomes many shortcomings of standard refrigeration-based direct expansion cooling. DEVap decouples cooling and dehumidification performance, which results in independent temperature and humidity control. The energy input is largely switched away from electricity to low-grade thermal energy that can be sourced from fuels such as natural gas, waste heat, solar, or biofuels.

  16. A packed bed dehumidifier/regenerator for solar air conditioning with liquid desiccants

    NASA Astrophysics Data System (ADS)

    Factor, H. M.; Grossman, G.

    1980-01-01

    A packed column air-liquid contactor has been studied in application to air dehumidification and regeneration in solar air conditioning with liquid desiccants. A theoretical model has been developed to predict the performance of the device under various operating conditions. Computer simulations based on the model are presented which indicate the practical range of air to liquid flux ratios and associated changes in air humidity and desiccant concentration. An experimental apparatus has been constructed and experiments performed with Monoethylene Glycol (MEG) and Lithium Bromide as desiccants. MEG experiments have yielded inaccurate results and have pointed out some practical problems associated with the use of Glycols. LiBr experiments show very good agreement with the theoretical model. Preheating of the air is shown to greatly enhance desiccant regeneration. The packed column yields good results as a dehumidifier/regenerator, provided pressure drop can be reduced with the use of suitable packing.

  17. SCHOOL AIR CONDITIONING/CASE STUDY, MCPHERSON HIGH SCHOOL.

    ERIC Educational Resources Information Center

    OSTENBERG, JOE W.

    THE STANFORD UNIVERSITY SCHOOL PLANNING LABORATORIES CONDUCTED AN EDUCATIONAL SURVEY OF THE EDUCATIONAL NEEDS OF THE MCPHERSON CITY SCHOOLS BY STUDYING THE EXISTING CONDITIONS, LOCAL ECONOMIES, AND POTENTIAL POPULATION GROWTH. IT WAS RECOMMENDED THAT A NEW SENIOR HIGH BE BUILT TO HOUSE 700-750 STUDENTS, THE ANTICIPATED ENROLLMENT 10 YEARS AFTER…

  18. System and method for conditioning intake air to an internal combustion engine

    SciTech Connect

    Sellnau, Mark C.

    2015-08-04

    A system for conditioning the intake air to an internal combustion engine includes a means to boost the pressure of the intake air to the engine and a liquid cooled charge air cooler disposed between the output of the boost means and the charge air intake of the engine. Valves in the coolant system can be actuated so as to define a first configuration in which engine cooling is performed by coolant circulating in a first coolant loop at one temperature, and charge air cooling is performed by coolant flowing in a second coolant loop at a lower temperature. The valves can be actuated so as to define a second configuration in which coolant that has flowed through the engine can be routed through the charge air cooler. The temperature of intake air to the engine can be controlled over a wide range of engine operation.

  19. Indoor Airflow Simulation inside Lecture Room: A CFD Approach

    NASA Astrophysics Data System (ADS)

    Lin, S.; Tee, B. T.; Tan, C. F.

    2015-09-01

    Indoor air flow distribution is important as it will affect the productivity of the occupants. Poor air flow distribution not only cause discomfort to the occupants but also influence their ability to conduct their activities. The main purpose of this study is to investigate the indoor air flow inside lecture rooms through CFD simulation approach. Two types of air-conditioning configuration system in lecture rooms have been selected for this study which includes the split unit and centralized system. The air flow distribution between these two systems are analyzed and compared. Physical measurement is conducted using a velocity meter for validation purpose. CFD simulation is developed by using ANSYS Fluent software. The results specifically the air velocity and temperature data are compared and validated. Based on the findings, design recommendation is proposed with the aim to improve on the current air flow distribution in the lecture rooms.

  20. Air conditioning in a tropical climate: Impacts upon European residents in Darwin, Australia

    NASA Astrophysics Data System (ADS)

    Auliciems, A.; Dedear, R.

    1986-09-01

    The efficacy of current practices in air conditioning is investigated in the two monsoonal seasons in Darwin. Assessment is made of atmospheric parameters, clothing, metabolic rate. Some 1000 questionnaires are applied dealing with adaptations, health perceptions and preferences as related to air cooling and ventilation. The findings are discussed with reference to energy balance calculations and current models of psychological control in thermoregulation. The results indicate that Darwin's population is considerably overcooled, and contrary to assumptions and practice, air conditioning is not desired in office buildings during the “Dry”. In the home, air conditioning is not regarded as essential. The indications are that a rationalization of air cooling to comply with natural variability in warmth would lead to a significant reduction in energy consumption, and an overall enhancement to the health and comfort of the population through the greater ventilation rates that would be economically feasible were design temperatures lifted.

  1. Temperature and Humidity Independent Control Research on Ground Source Heat Pump Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Chen, G.; Wang, L. L.

    Taking green demonstration center building air conditioning system as an example, this paper presents the temperature and humidity independent control system combined with ground source heat pump system, emphasis on the design of dry terminal device system, fresh air system and ground source heat pump system.

  2. Colonization by Cladosporium spp. of painted metal surfaces associated with heating and air conditioning systems

    NASA Technical Reports Server (NTRS)

    Ahearn, D. G.; Simmons, R. B.; Switzer, K. F.; Ajello, L.; Pierson, D. L.

    1991-01-01

    Cladosporium cladosporioides and C. hebarum colonized painted metal surfaces of covering panels and register vents of heating, air conditioning and ventilation systems. Hyphae penetrated the paint film and developed characteristic conidiophores and conidia. The colonies were tightly appressed to the metal surface and conidia were not readily detectable via standard air sampling procedures.

  3. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to simulate the impact of an ambient heat load on the power requirements of the vehicle's air... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating... be shown that all of the ambient test condition performance requirements are satisfied. (d)...

  4. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Air conditioning environmental test facility ambient requirements. 86.161-00 Section 86.161-00 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations...

  5. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to simulate the impact of an ambient heat load on the power requirements of the vehicle's air... elements that are discussed are ambient air temperature and humidity, minimum test cell size, solar heating... be shown that all of the ambient test condition performance requirements are satisfied. (d)...

  6. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Air conditioning environmental test facility ambient requirements. 86.161-00 Section 86.161-00 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations...

  7. 40 CFR 86.161-00 - Air conditioning environmental test facility ambient requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Air conditioning environmental test facility ambient requirements. 86.161-00 Section 86.161-00 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations...

  8. 40 CFR 86.167-17 - AC17 Air Conditioning Emissions Test Procedure.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false AC17 Air Conditioning Emissions Test Procedure. 86.167-17 Section 86.167-17 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1977 and Later...

  9. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Method for calculating emissions due to air conditioning leakage. 86.166-12 Section 86.166-12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for...

  10. 40 CFR 86.166-12 - Method for calculating emissions due to air conditioning leakage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Method for calculating emissions due to air conditioning leakage. 86.166-12 Section 86.166-12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for...

  11. 40 CFR 86.165-12 - Air conditioning idle test procedure.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Air conditioning idle test procedure. 86.165-12 Section 86.165-12 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission Regulations for 1977 and Later Model Year...

  12. Air Conditioning, Heating, and Ventilating: Construction, Supervision, and Inspection. Course of Study.

    ERIC Educational Resources Information Center

    Messer, John D.

    This course of study on air conditioning, heating, and ventilating is part of a construction, supervision, and inspection series, which provides instructional materials for community or junior college technical courses in the inspection program. Material covered pertains to: piping and piping systems; air movers; boilers; heat exchangers; cooling…

  13. Influence of Boundary Conditions on Simulated U.S. Air Quality

    EPA Science Inventory

    One of the key inputs to regional-scale photochemical models frequently used in air quality planning and forecasting applications are chemical boundary conditions representing background pollutant concentrations originating outside the regional modeling domain. A number of studie...

  14. Evaluating Membrane Processes for Air Conditioning; Highlights in Research and Development, NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-06-01

    This NREL Highlight discusses a recent state-of-the-art review of membrane processes for air conditioning that identifies future research opportunities. This highlight is being developed for the June 2015 S&T Alliance Board meeting.

  15. Fuel Savings and Emission Reductions from Next-Generation Mobile Air Conditioning Technology in India: Preprint

    SciTech Connect

    Chaney, L.; Thundiyil, K.; Chidambaram, S.; Abbi, Y. P.; Anderson, S.

    2007-05-01

    This paper quantifies the mobile air-conditioning fuel consumption of the typical Indian vehicle, exploring potential fuel savings and emissions reductions these systems for the next generation of vehicles.

  16. DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, ...

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

    DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, FACING SOUTHEAST - Cape Canaveral Air Force Station, Launch Complex 39, Launch Control Center, LCC Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  17. DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 4, ...

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

    DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 4, FACING WEST - Cape Canaveral Air Force Station, Launch Complex 39, Launch Control Center, LCC Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  18. DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, ...

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

    DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, FACING NORTH - Cape Canaveral Air Force Station, Launch Complex 39, Launch Control Center, LCC Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  19. DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, ...

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

    DETAIL VIEW OF OPERATIONS MANAGEMENT ROOM, FIRING ROOM NO. 3, FACING EAST - Cape Canaveral Air Force Station, Launch Complex 39, Launch Control Center, LCC Road, East of Kennedy Parkway North, Cape Canaveral, Brevard County, FL

  20. 16. Readiness Crew Building interior, Room 105, former briefing room, ...

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

    16. Readiness Crew Building interior, Room 105, former briefing room, looking southeast. Thalheimer - Whiteman Air Force Base, Bomber Alert Facility S-6, 1300 Alert Road, Knob Noster, Johnson County, MO

  1. MACHINE ROOM FROM DOORWAY TO COMMUNICATIONS ROOM, VIEW FACING SOUTHWEST. ...

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

    MACHINE ROOM FROM DOORWAY TO COMMUNICATIONS ROOM, VIEW FACING SOUTHWEST. - Naval Air Station Barbers Point, World War II Command Center, Midway Street east of Lexington Avenue, Ewa, Honolulu County, HI

  2. 13. Interior view of conference room looking into break room ...

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

    13. Interior view of conference room looking into break room beyond; along west side of upper level; view to southwest. - Ellsworth Air Force Base, Mess Hall & Administration Building, 1301 Ellsworth Street, Blackhawk, Meade County, SD

  3. Solar technology assessment project. Volume 4: Solar air conditioning: Active, hybrid and passive

    NASA Astrophysics Data System (ADS)

    Yellott, J. I.

    1981-04-01

    The status of absorption cycle solar air conditioning and the Rankine cycle solar cooling system is reviewed. Vapor jet ejector chillers, solar pond based cooling, and photovoltaic compression air conditioning are also briefly discussed. Hybrid solar cooling by direct and indirect evaporative cooling, and dehumidification by desiccation are described and discussed. Passive solar cooling by convective and radiative processes, evaporative cooling by passive processes, and cooling with roof ponds and movable insulation are reviewed. Federal and state involvement in solar cooling is discussed.

  4. A Comparative Study of Sound Speed in Air at Room Temperature between a Pressure Sensor and a Sound Sensor

    ERIC Educational Resources Information Center

    Amrani, D.

    2013-01-01

    This paper deals with the comparison of sound speed measurements in air using two types of sensor that are widely employed in physics and engineering education, namely a pressure sensor and a sound sensor. A computer-based laboratory with pressure and sound sensors was used to carry out measurements of air through a 60 ml syringe. The fast Fourier…

  5. Looking west in the basement utility room, room 24, overview ...

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

    Looking west in the basement utility room, room 24, overview of air handling system, large walk-in filter, large ducts, pipes, and gauges - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  6. Contribution of air conditioning adoption to future energy use under global warming.

    PubMed

    Davis, Lucas W; Gertler, Paul J

    2015-05-12

    As household incomes rise around the world and global temperatures go up, the use of air conditioning is poised to increase dramatically. Air conditioning growth is expected to be particularly strong in middle-income countries, but direct empirical evidence is scarce. In this paper we use high-quality microdata from Mexico to describe the relationship between temperature, income, and air conditioning. We describe both how electricity consumption increases with temperature given current levels of air conditioning, and how climate and income drive air conditioning adoption decisions. We then combine these estimates with predicted end-of-century temperature changes to forecast future energy consumption. Under conservative assumptions about household income, our model predicts near-universal saturation of air conditioning in all warm areas within just a few decades. Temperature increases contribute to this surge in adoption, but income growth by itself explains most of the increase. What this will mean for electricity consumption and carbon dioxide emissions depends on the pace of technological change. Continued advances in energy efficiency or the development of new cooling technologies could reduce the energy consumption impacts. Similarly, growth in low-carbon electricity generation could mitigate the increases in carbon dioxide emissions. However, the paper illustrates the enormous potential impacts in this sector, highlighting the importance of future research on adaptation and underscoring the urgent need for global action on climate change. PMID:25918391

  7. Contribution of air conditioning adoption to future energy use under global warming

    PubMed Central

    Davis, Lucas W.; Gertler, Paul J.

    2015-01-01

    As household incomes rise around the world and global temperatures go up, the use of air conditioning is poised to increase dramatically. Air conditioning growth is expected to be particularly strong in middle-income countries, but direct empirical evidence is scarce. In this paper we use high-quality microdata from Mexico to describe the relationship between temperature, income, and air conditioning. We describe both how electricity consumption increases with temperature given current levels of air conditioning, and how climate and income drive air conditioning adoption decisions. We then combine these estimates with predicted end-of-century temperature changes to forecast future energy consumption. Under conservative assumptions about household income, our model predicts near-universal saturation of air conditioning in all warm areas within just a few decades. Temperature increases contribute to this surge in adoption, but income growth by itself explains most of the increase. What this will mean for electricity consumption and carbon dioxide emissions depends on the pace of technological change. Continued advances in energy efficiency or the development of new cooling technologies could reduce the energy consumption impacts. Similarly, growth in low-carbon electricity generation could mitigate the increases in carbon dioxide emissions. However, the paper illustrates the enormous potential impacts in this sector, highlighting the importance of future research on adaptation and underscoring the urgent need for global action on climate change. PMID:25918391

  8. Influence of Ventilation Ratio on Desiccant Air Conditioning System's Efficiency Performance

    NASA Astrophysics Data System (ADS)

    Tran, Thien Nha; Akisawa, Atsushi; Kashiwagi, Takao; Hamamoto, Yoshinori

    Ventilation air is a concern for engineers since ventilated air controls indoor air contamination; additional ventilation, however, increases the energy consumption of buildings. The study investigates the energy efficiency performance of the desiccant dehumidification air conditioning system in the context of ventilation for a hot-humid climate such as summer in Japan. The investigation focuses on the variable ratio of ventilation air as required by the application of air conditioning system. The COP of the desiccant air conditioning system is determined. The evaluation is subsequently performed by comparing the desiccant based system with the conventional absorption cooling system and the vapor compression cooling system. Based on 12 desiccant rotor simulations, it is found that the desiccant regeneration temperature required varies between 47°C to 85°C as ventilation ratio increases from 0. 0 to 100%, and up to 52. 5°C as the ventilation ratio achieves 14%. The heat required for regenerating desiccant accounts for 55% and higher of the system's total heat consumption; the system is expected to be energy efficient by using wasted heat from the absorption chiller for desiccant regeneration; and its energy efficiency expands as the ratio of ventilation air rises above 15% compared with the conventional absorption cooling system. The energy efficiency also benefits as the ratio rises beyond 70% against the conventional vapor compression cooling system.

  9. Long-term room-temperature hydrazine/air fuel cells based on low-cost nanotextured Cu-Ni catalysts

    NASA Astrophysics Data System (ADS)

    Filanovsky, Boris; Granot, Eran; Presman, Igor; Kuras, Iliya; Patolsky, Fernando

    2014-01-01

    We present here a long-term room-temperature (RT) direct-liquid hydrazine/air fuel cell device. This hydrazine/air fuel cell is based on low-cost easily-prepared nanotextured Cu-Ni anodes as the hydrazine (Hz) catalyst, combined with a commercial anion-exchange membrane film and a commercial air cathode. In addition, our hydrazine/air fuel cell consists on an improved novel design that results in remarkably high mechanical and chemical stabilities for long periods of operation. This hydrazine/air fuel cell can operates continuously for about ∼2000 h (limited mainly by cathode and membrane deterioration) with continuous fuel supply, and supplies about 0.58 V at 1 A (14.3 mA cm-2, with a discharge efficiency of about 70% (drift is less than 0.01% h-1), and appears to be suitable for mass production. The use of optimally-combined multi-metal electrodes suggests the possibility to create novel catalysts of improved electrochemical efficiency and stability. Our fuel cell devices can find broad applications in different civilian and military field mobile and stationary uses, for instance, in future fuel-cell operated vehicles and stationary back-up power electrical stations.

  10. Modeling Validation and Control Analysis for Controlled Temperature and Humidity of Air Conditioning System

    PubMed Central

    Lee, Jing-Nang; Lin, Tsung-Min

    2014-01-01

    This study constructs an energy based model of thermal system for controlled temperature and humidity air conditioning system, and introduces the influence of the mass flow rate, heater and humidifier for proposed control criteria to achieve the controlled temperature and humidity of air conditioning system. Then, the reliability of proposed thermal system model is established by both MATLAB dynamic simulation and the literature validation. Finally, the PID control strategy is applied for controlling the air mass flow rate, humidifying capacity, and heating, capacity. The simulation results show that the temperature and humidity are stable at 541 sec, the disturbance of temperature is only 0.14°C, 0006 kgw/kgda in steady-state error of humidity ratio, and the error rate is only 7.5%. The results prove that the proposed system is an effective controlled temperature and humidity of an air conditioning system. PMID:25250390

  11. Correction of Temperatures of Air-Cooled Engine Cylinders for Variation in Engine and Cooling Conditions

    NASA Technical Reports Server (NTRS)

    Schey, Oscar W; Pinkel, Benjamin; Ellerbrock, Herman H , Jr

    1939-01-01

    Factors are obtained from semiempirical equations for correcting engine-cylinder temperatures for variation in important engine and cooling conditions. The variation of engine temperatures with atmospheric temperature is treated in detail, and correction factors are obtained for various flight and test conditions, such as climb at constant indicated air speed, level flight, ground running, take-off, constant speed of cooling air, and constant mass flow of cooling air. Seven conventional air-cooled engine cylinders enclosed in jackets and cooled by a blower were tested to determine the effect of cooling-air temperature and carburetor-air temperature on cylinder temperatures. The cooling air temperature was varied from approximately 80 degrees F. to 230 degrees F. and the carburetor-air temperature from approximately 40 degrees F. to 160 degrees F. Tests were made over a large range of engine speeds, brake mean effective pressures, and pressure drops across the cylinder. The correction factors obtained experimentally are compared with those obtained from the semiempirical equations and a fair agreement is noted.

  12. Computational study of room scattering influence in the THOR BNCT treatment room.

    PubMed

    Hsiao, Ming-Chen; Liu, Yuan-Hao; Jiang, Shiang-Huei

    2014-06-01

    BNCT dosimetry has often employed heavy Monte Carlo calculations for the beam characterization and the dose determination. However, these calculations commonly ignored the scattering influence between the radiations and the room structure materials in order to facilitate the calculation speed. The aim of this article attempts to explore how the room scattering affects the physical quantities such as the capture reaction rate and the gamma-ray dose rate under in-phantom and free-air conditions in the THOR BNCT treatment room. The geometry and structure materials of the treatment room were simulated in detail. The capture reaction rates per atom, as well as the gamma-ray dose rate were calculated in various sizes of phantoms and in the free-air condition. Results of this study showed that the room scattering has significant influence on the physical quantities, whether in small phantoms or in the free-air condition. This paper may be of importance in explaining the discrepancies between measurements and calculations in the BNCT dosimetry using small phantoms, in addition to provide a useful consideration with a better understanding of how the room scattering influence acts in a BNCT facility. PMID:24365466

  13. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  14. Effects of air annealing on CdS quantum dots thin film grown at room temperature by CBD technique intended for photosensor applications

    SciTech Connect

    Shaikh, Shaheed U.; Desale, Dipalee J.; Siddiqui, Farha Y.; Ghosh, Arindam; Birajadar, Ravikiran B.; Ghule, Anil V.; Sharma, Ramphal

    2012-11-15

    Graphical abstract: The effect of different intensities (40, 60 100 and 200 W) of light on CdS quantum dots thin film annealed at 350 °C indicating enhancement in (a) photo-current and (b) photosensitivity. Highlights: ► The preparation of CdS nanodot thin film at room temperature by M-CBD technique. ► Study of air annealing on prepared CdS nanodots thin film. ► The optimized annealing temperature for CdS nanodot thin film is 350 °C. ► Modified CdS thin films can be used in photosensor application. -- Abstract: CdS quantum dots thin-films have been deposited onto the glass substrate at room temperature using modified chemical bath deposition technique. The prepared thin films were further annealed in air atmosphere at 150, 250 and 350 °C for 1 h and subsequently characterized by scanning electron microscopy, ultraviolet–visible spectroscopy, electrical resistivity and I–V system. The modifications observed in morphology and opto-electrical properties of the thin films are presented.

  15. Improving forecast skill by assimilation of quality-controlled AIRS temperature retrievals under partially cloudy conditions

    NASA Astrophysics Data System (ADS)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Liu, E.; Riishojgaard, L. P.; Terry, J.; Jusem, J. C.

    2008-04-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite is now recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  16. Improving Forecast Skill by Assimilation of Quality-controlled AIRS Temperature Retrievals under Partially Cloudy Conditions

    NASA Technical Reports Server (NTRS)

    Reale, O.; Susskind, J.; Rosenberg, R.; Brin, E.; Riishojgaard, L.; Liu, E.; Terry, J.; Jusem, J. C.

    2007-01-01

    The National Aeronautics and Space Administration (NASA) Atmospheric Infrared Sounder (AIRS) on board the Aqua satellite has been long recognized as an important contributor towards the improvement of weather forecasts. At this time only a small fraction of the total data produced by AIRS is being used by operational weather systems. In fact, in addition to effects of thinning and quality control, the only AIRS data assimilated are radiance observations of channels unaffected by clouds. Observations in mid-lower tropospheric sounding AIRS channels are assimilated primarily under completely clear-sky conditions, thus imposing a very severe limitation on the horizontal distribution of the AIRS-derived information. In this work it is shown that the ability to derive accurate temperature profiles from AIRS observations in partially cloud-contaminated areas can be utilized to further improve the impact of AIRS observations in a global model and forecasting system. The analyses produced by assimilating AIRS temperature profiles obtained under partial cloud cover result in a substantially colder representation of the northern hemisphere lower midtroposphere at higher latitudes. This temperature difference has a strong impact, through hydrostatic adjustment, in the midtropospheric geopotential heights, which causes a different representation of the polar vortex especially over northeastern Siberia and Alaska. The AIRS-induced anomaly propagates through the model's dynamics producing improved 5-day forecasts.

  17. Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration

    SciTech Connect

    2010-09-01

    BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics’ design uses a novel property of certain materials, called “magnetocaloric materials”, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses no ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.

  18. Heterogeneous copper-catalyzed hydroxylation of aryl iodides under air conditions.

    PubMed

    Ding, Guodong; Han, Hongling; Jiang, Tao; Wu, Tianbin; Han, Buxing

    2014-08-21

    In this work, the ligand-free heterogeneous copper Cu-g-C3N4 was synthesized and used for the hydroxylation of aryl iodides to synthesize phenols using cheap bases. The catalyst was conveniently prepared, air-tolerant, reusable and scalable, and is very efficient for a wide range of substrates. The synthesis of substituted phenols can be carried out under air conditions and has great potential for practical applications. PMID:24947007

  19. Impact of the electric compressor for automotive air conditioning system on fuel consumption and performance analysis

    NASA Astrophysics Data System (ADS)

    Zulkifli, A. A.; Dahlan, A. A.; Zulkifli, A. H.; Nasution, H.; Aziz, A. A.; Perang, M. R. M.; Jamil, H. M.; Misseri, M. N.

    2015-12-01

    Air conditioning system is the biggest auxiliary load in a vehicle where the compressor consumed the largest. Problem with conventional compressor is the cooling capacity cannot be control directly to fulfill the demand of thermal load inside vehicle cabin. This study is conducted experimentally to analyze the difference of fuel usage and air conditioning performance between conventional compressor and electric compressor of the air conditioning system in automobile. The electric compressor is powered by the car battery in non-electric vehicle which the alternator will recharge the battery. The car is setup on a roller dynamometer and the vehicle speed is varied at 0, 30, 60, 90 and 110 km/h at cabin temperature of 25°C and internal heat load of 100 and 400 Watt. The results shows electric compressor has better fuel consumption and coefficient of performance compared to the conventional compressor.

  20. An Expert Fault Diagnosis System for Vehicle Air Conditioning Product Development

    NASA Astrophysics Data System (ADS)

    Tan, C. F.; Tee, B. T.; Khalil, S. N.; Chen, W.; Rauterberg, G. W. M.

    2015-09-01

    The paper describes the development of the vehicle air-conditioning fault diagnosis system in automotive industries with expert system shell. The main aim of the research is to diagnose the problem of new vehicle air-conditioning system development process and select the most suitable solution to the problems. In the vehicle air-conditioning manufacturing industry, process can be very costly where an expert and experience personnel needed in certain circumstances. The expert of in the industry will retire or resign from time to time. When the expert is absent, their experience and knowledge is difficult to retrieve or lost forever. Expert system is a convenient method to replace expert. By replacing the expert with expert system, the accuracy of the processes will be increased compared to the conventional way. Therefore, the quality of product services that are produced will be finer and better. The inputs for the fault diagnosis are based on design data and experience of the engineer.

  1. Carbon Dioxide and Ionic Liquid Refrigerants: Compact, Efficient Air Conditioning with Ionic Liquid-Based Refrigerants

    SciTech Connect

    2010-10-01

    BEETIT Project: Notre Dame is developing an air-conditioning system with a new ionic liquid and CO2 as the working fluid. Synthetic refrigerants used in air conditioning and refrigeration systems are potent GHGs and can trap 1,000 times more heat in the atmosphere than CO2 alone—making CO2 an attractive alternative for synthetic refrigerants in cooling systems. However, operating cooling systems with pure CO2 requires prohibitively high pressures and expensive hardware. Notre Dame is creating a new fluid made of CO2 and ionic liquid that enables the use of CO2 at low pressures and requires minimal changes to existing hardware and production lines. This new fluid also produces no harmful emissions and can improve the efficiency of air conditioning systems— enabling new use of CO2 as a refrigerant in cooling systems.

  2. Potential Evaluation of Solar Heat Assisted Desiccant Hybrid Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Tran, Thien Nha; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    The solar thermal driven desiccant dehumidification-absorption cooling hybrid system has superior advantage in hot-humid climate regions. The reasonable air processing of desiccant hybrid air conditioning system and the utility of clean and free energy make the system environment friendly and energy efficient. The study investigates the performance of the desiccant dehumidification air conditioning systems with solar thermal assistant. The investigation is performed for three cases which are combinations of solar thermal and absorption cooling systems with different heat supply temperature levels. Two solar thermal systems are used in the study: the flat plate collector (FPC) and the vacuum tube with compound parabolic concentrator (CPC). The single-effect and high energy efficient double-, triple-effect LiBr-water absorption cooling cycles are considered for cooling systems. COP of desiccant hybrid air conditioning systems are determined. The evaluation of these systems is subsequently performed. The single effect absorption cooling cycle combined with the flat plate collector solar system is found to be the most energy efficient air conditioning system.

  3. From lithium to sodium: cell chemistry of room temperature sodium-air and sodium-sulfur batteries.

    PubMed

    Adelhelm, Philipp; Hartmann, Pascal; Bender, Conrad L; Busche, Martin; Eufinger, Christine; Janek, Juergen

    2015-01-01

    Research devoted to room temperature lithium-sulfur (Li/S8) and lithium-oxygen (Li/O2) batteries has significantly increased over the past ten years. The race to develop such cell systems is mainly motivated by the very high theoretical energy density and the abundance of sulfur and oxygen. The cell chemistry, however, is complex, and progress toward practical device development remains hampered by some fundamental key issues, which are currently being tackled by numerous approaches. Quite surprisingly, not much is known about the analogous sodium-based battery systems, although the already commercialized, high-temperature Na/S8 and Na/NiCl2 batteries suggest that a rechargeable battery based on sodium is feasible on a large scale. Moreover, the natural abundance of sodium is an attractive benefit for the development of batteries based on low cost components. This review provides a summary of the state-of-the-art knowledge on lithium-sulfur and lithium-oxygen batteries and a direct comparison with the analogous sodium systems. The general properties, major benefits and challenges, recent strategies for performance improvements and general guidelines for further development are summarized and critically discussed. In general, the substitution of lithium for sodium has a strong impact on the overall properties of the cell reaction and differences in ion transport, phase stability, electrode potential, energy density, etc. can be thus expected. Whether these differences will benefit a more reversible cell chemistry is still an open question, but some of the first reports on room temperature Na/S8 and Na/O2 cells already show some exciting differences as compared to the established Li/S8 and Li/O2 systems. PMID:25977873

  4. From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

    PubMed Central

    Hartmann, Pascal; Bender, Conrad L; Busche, Martin; Eufinger, Christine

    2015-01-01

    Summary Research devoted to room temperature lithium–sulfur (Li/S8) and lithium–oxygen (Li/O2) batteries has significantly increased over the past ten years. The race to develop such cell systems is mainly motivated by the very high theoretical energy density and the abundance of sulfur and oxygen. The cell chemistry, however, is complex, and progress toward practical device development remains hampered by some fundamental key issues, which are currently being tackled by numerous approaches. Quite surprisingly, not much is known about the analogous sodium-based battery systems, although the already commercialized, high-temperature Na/S8 and Na/NiCl2 batteries suggest that a rechargeable battery based on sodium is feasible on a large scale. Moreover, the natural abundance of sodium is an attractive benefit for the development of batteries based on low cost components. This review provides a summary of the state-of-the-art knowledge on lithium–sulfur and lithium–oxygen batteries and a direct comparison with the analogous sodium systems. The general properties, major benefits and challenges, recent strategies for performance improvements and general guidelines for further development are summarized and critically discussed. In general, the substitution of lithium for sodium has a strong impact on the overall properties of the cell reaction and differences in ion transport, phase stability, electrode potential, energy density, etc. can be thus expected. Whether these differences will benefit a more reversible cell chemistry is still an open question, but some of the first reports on room temperature Na/S8 and Na/O2 cells already show some exciting differences as compared to the established Li/S8 and Li/O2 systems. PMID:25977873

  5. Association between Air Pollutants and Asthma Emergency Room Visits and Hospital Admissions in Time Series Studies: A Systematic Review and Meta-Analysis

    PubMed Central

    Zheng, Xue-yan; Ding, Hong; Jiang, Li-na; Chen, Shao-wei; Zheng, Jin-ping; Qiu, Min; Zhou, Ying-xue; Chen, Qing; Guan, Wei-jie

    2015-01-01

    Background Air pollution constitutes a significant stimulus of asthma exacerbations; however, the impacts of exposure to major air pollutants on asthma-related hospital admissions and emergency room visits (ERVs) have not been fully determined. Objective We sought to quantify the associations between short-term exposure to air pollutants [ozone (O3), carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and particulate matter ≤10μm (PM10) and PM2.5] and the asthma-related emergency room visits (ERV) and hospitalizations. Methods Systematic computerized searches without language limitation were performed. Pooled relative risks (RRs) and 95% confidence intervals (95%CIs) were estimated using the random-effect models. Sensitivity analyses and subgroup analyses were also performed. Results After screening of 246 studies, 87 were included in our analyses. Air pollutants were associated with significantly increased risks of asthma ERVs and hospitalizations [O3: RR(95%CI), 1.009 (1.006, 1.011); I2 = 87.8%, population-attributable fraction (PAF) (95%CI): 0.8 (0.6, 1.1); CO: RR(95%CI), 1.045 (1.029, 1.061); I2 = 85.7%, PAF (95%CI): 4.3 (2.8, 5.7); NO2: RR(95%CI), 1.018 (1.014, 1.022); I2 = 87.6%, PAF (95%CI): 1.8 (1.4, 2.2); SO2: RR(95%CI), 1.011 (1.007, 1.015); I2 = 77.1%, PAF (95%CI): 1.1 (0.7, 1.5); PM10: RR(95%CI), 1.010 (1.008, 1.013); I2 = 69.1%, PAF (95%CI): 1.1 (0.8, 1.3); PM2.5: RR(95%CI), 1.023 (1.015, 1.031); I2 = 82.8%, PAF (95%CI): 2.3 (1.5, 3.1)]. Sensitivity analyses yielded compatible findings as compared with the overall analyses without publication bias. Stronger associations were found in hospitalized males, children and elderly patients in warm seasons with lag of 2 days or greater. Conclusion Short-term exposures to air pollutants account for increased risks of asthma-related ERVs and hospitalizations that constitute a considerable healthcare utilization and socioeconomic burden. PMID:26382947

  6. SUMMARY OF ELECTRIC SERVICE COSTS FOR TOTALLY AIR CONDITIONED SCHOOLS PREPARED FOR HOUSTON INDEPENDENT SCHOOL DISTRICT, MAY 31, 1967.

    ERIC Educational Resources Information Center

    WHITESIDES, M.M.

    THIS REPORT IS A COMPILATION OF DATA ON ELECTRIC AIR CONDITIONING COSTS, OPERATIONS AND MAINTENANCE. AIR CONDITIONING UNITS ARE COMPARED IN TERMS OF ELECTRIC VERSUS NON-ELECTRIC, AUTOMATIC VERSUS OPERATED, AIR COOLED VERSUS WATER COOLED, RECIPROCATING VERSUS CENTRIFUGAL COMPRESSORS, SPACE AND NOISE, REHEAT, MAINTENANCE AND ORIGINAL COST. DATA ARE…

  7. Minimum Energy type of Air Conditioning Controlby Switching Equilibrium Point of Control Variables

    NASA Astrophysics Data System (ADS)

    Takahata, Akihiko; Uchida, Kenko; Taira, Utaro

    In this paper, we propose an algorithm realizing minimum energy control for air conditioning. In the air conditioning system, control inputs are valve-open-value of cooler, heater and humidifier, and controlled variables are indoor temperature and humidity. That is, this system has three inputs and two outputs. The main step of the minimum energy algorithm is to switch two of the three actuators, depending on setpoints, for minimizing consumption energy. We apply this algorithm to a real plant, and show validity of the algorithm.

  8. Room-temperature thermal-resistance measurements of new and existing materials for shipboard air-duct systems

    SciTech Connect

    Zarr, R.R.; Somers, T.A.

    1988-10-01

    Thermal resistance measurements of conventional and composite-material insulation for shipboard air duct systems are described. Conventional shipboard air ducts are constructed of metal walls insulated externally with fibrous-glass board. Composite materials are being considered as replacements for these duct walls. Thermal measurements were conducted using the National Bureau of Standards 1-meter Guarded Hot Plate at a mean temperature of 23.9/sup 0/C (75/sup 0/F). Measurements of the fibrous-glass board specimens were within 3% of certified values of NBS SRM 1450a, fibrous-glass board. Measurements of two aramid-fiber honeycomb specimens were approximately one-half the thermal resistance of the fibrous-glass board specimens.

  9. Weather elements, chemical air pollutants and airborne pollen influencing asthma emergency room visits in Szeged, Hungary: performance of two objective weather classifications

    NASA Astrophysics Data System (ADS)

    Makra, László; Puskás, János; Matyasovszky, István; Csépe, Zoltán; Lelovics, Enikő; Bálint, Beatrix; Tusnády, Gábor

    2015-09-01

    Weather classification approaches may be useful tools in modelling the occurrence of respiratory diseases. The aim of the study is to compare the performance of an objectively defined weather classification and the Spatial Synoptic Classification (SSC) in classifying emergency department (ED) visits for acute asthma depending from weather, air pollutants, and airborne pollen variables for Szeged, Hungary, for the 9-year period 1999-2007. The research is performed for three different pollen-related periods of the year and the annual data set. According to age and gender, nine patient categories, eight meteorological variables, seven chemical air pollutants, and two pollen categories were used. In general, partly dry and cold air and partly warm and humid air aggravate substantially the symptoms of asthmatics. Our major findings are consistent with this establishment. Namely, for the objectively defined weather types favourable conditions for asthma ER visits occur when an anticyclonic ridge weather situation happens with near extreme temperature and humidity parameters. Accordingly, the SSC weather types facilitate aggravating asthmatic conditions if warm or cool weather occur with high humidity in both cases. Favourable conditions for asthma attacks are confirmed in the extreme seasons when atmospheric stability contributes to enrichment of air pollutants. The total efficiency of the two classification approaches is similar in spite of the fact that the methodology for derivation of the individual types within the two classification approaches is completely different.

  10. Weather elements, chemical air pollutants and airborne pollen influencing asthma emergency room visits in Szeged, Hungary: performance of two objective weather classifications.

    PubMed

    Makra, László; Puskás, János; Matyasovszky, István; Csépe, Zoltán; Lelovics, Enikő; Bálint, Beatrix; Tusnády, Gábor

    2015-09-01

    Weather classification approaches may be useful tools in modelling the occurrence of respiratory diseases. The aim of the study is to compare the performance of an objectively defined weather classification and the Spatial Synoptic Classification (SSC) in classifying emergency department (ED) visits for acute asthma depending from weather, air pollutants, and airborne pollen variables for Szeged, Hungary, for the 9-year period 1999-2007. The research is performed for three different pollen-related periods of the year and the annual data set. According to age and gender, nine patient categories, eight meteorological variables, seven chemical air pollutants, and two pollen categories were used. In general, partly dry and cold air and partly warm and humid air aggravate substantially the symptoms of asthmatics. Our major findings are consistent with this establishment. Namely, for the objectively defined weather types favourable conditions for asthma ER visits occur when an anticyclonic ridge weather situation happens with near extreme temperature and humidity parameters. Accordingly, the SSC weather types facilitate aggravating asthmatic conditions if warm or cool weather occur with high humidity in both cases. Favourable conditions for asthma attacks are confirmed in the extreme seasons when atmospheric stability contributes to enrichment of air pollutants. The total efficiency of the two classification approaches is similar in spite of the fact that the methodology for derivation of the individual types within the two classification approaches is completely different. PMID:25504051

  11. Future Air Conditioning Energy Consumption in Developing Countriesand what can be done about it: The Potential of Efficiency in theResidential Sector

    SciTech Connect

    McNeil, Michael A.; Letschert, Virginie E.

    2007-05-01

    The dynamics of air conditioning are of particular interestto energy analysts, both because of the high energy consumption of thisproduct, but also its disproportionate impact on peak load. This paperaddresses the special role of this end use as a driver of residentialelectricity consumption in rapidly developing economies. Recent historyhas shown that air conditioner ownership can grow grows more rapidly thaneconomic growth in warm-climate countries. In 1990, less than a percentof urban Chinese households owned an air conditioner; by 2003 this numberrose to 62 percent. The evidence suggests a similar explosion of airconditioner use in many other countries is not far behind. Room airconditioner purchases in India are currently growing at 20 percent peryear, with about half of these purchases attributed to the residentialsector. This paper draws on two distinct methodological elements toassess future residential air conditioner 'business as usual' electricityconsumption by country/region and to consider specific alternative 'highefficiency' scenarios. The first component is an econometric ownershipand use model based on household income, climate and demographicparameters. The second combines ownership forecasts and stock accountingwith geographically specific efficiency scenarios within a uniqueanalysis framework (BUENAS) developed by LBNL. The efficiency scenariomodule considers current efficiency baselines, available technologies,and achievable timelines for development of market transformationprograms, such as minimum efficiency performance standards (MEPS) andlabeling programs. The result is a detailed set of consumption andemissions scenarios for residential air conditioning.

  12. Optimization of microwave-assisted hot air drying conditions of okra using response surface methodology.

    PubMed

    Kumar, Deepak; Prasad, Suresh; Murthy, Ganti S

    2014-02-01

    Okra (Abelmoschus esculentus) was dried to a moisture level of 0.1 g water/g dry matter using a microwave-assisted hot air dryer. Response surface methodology was used to optimize the drying conditions based on specific energy consumption and quality of dried okra. The drying experiments were performed using a central composite rotatable design for three variables: air temperature (40-70 °C), air velocity (1-2 m/s) and microwave power level (0.5-2.5 W/g). The quality of dried okra was determined in terms of color change, rehydration ratio and hardness of texture. A second-order polynomial model was well fitted to all responses and high R(2) values (>0.8) were observed in all cases. The color change of dried okra was found higher at high microwave power and air temperatures. Rehydration properties were better for okra samples dried at higher microwave power levels. Specific energy consumption decreased with increase in microwave power due to decrease in drying time. The drying conditions of 1.51 m/s air velocity, 52.09 °C air temperature and 2.41 W/g microwave power were found optimum for product quality and minimum energy consumption for microwave-convective drying of okra. PMID:24493879

  13. Preliminary verification of instantaneous air temperature estimation for clear sky conditions based on SEBAL

    NASA Astrophysics Data System (ADS)

    Zhu, Shanyou; Zhou, Chuxuan; Zhang, Guixin; Zhang, Hailong; Hua, Junwei

    2016-03-01

    Spatially distributed near surface air temperature at the height of 2 m is an important input parameter for the land surface models. It is of great significance in both theoretical research and practical applications to retrieve instantaneous air temperature data from remote sensing observations. An approach based on Surface Energy Balance Algorithm for Land (SEBAL) to retrieve air temperature under clear sky conditions is presented. Taking the meteorological measurement data at one station as the reference and remotely sensed data as the model input, the research estimates the air temperature by using an iterative computation. The method was applied to the area of Jiangsu province for nine scenes by using MODIS data products, as well as part of Fujian province, China based on four scenes of Landsat 8 imagery. Comparing the air temperature estimated from the proposed method with that of the meteorological station measurement, results show that the root mean square error is 1.7 and 2.6 °C at 1000 and 30 m spatial resolution respectively. Sensitivity analysis of influencing factors reveals that land surface temperature is the most sensitive to the estimation precision. Research results indicate that the method has great potentiality to be used to estimate instantaneous air temperature distribution under clear sky conditions.

  14. Unique, low-energy air-conditioning system using naturally-frozen ice

    SciTech Connect

    Kirkpatrick, D.L.; Masoero, M.; Socolow, R.H.; Taylor, T.B.

    1981-01-01

    An effective low-energy-consumption air-conditioning system, using naturally-frozen ice as the heat sink, has been successfully demonstrated. During the summer of 1980, a test building at Princeton University was cooled using ice frozen during the previous winter. The ice is produced outdoors by spraying water into winter air, and stored until summer in an excavated reservoir under an insulating blanket. During the air-conditioning season, melt water from the bottom of the lined, ice-filled reservoir is pumped through a conventional water-to-air heat exchanger within the conditioned space, to provide air cooling and dehumidification. The water warmed in the exchange is returned to the reservoir, to be recooled to 0/sup 0/C by the remaining ice. This approach not only significantly reduces the total energy required to produce a given cooling effect relative to other means in current use, but also shifts the time of major energy use away from the electric utility's summer load peak period.

  15. Prediction of air temperature in the aircraft cabin under different operational conditions

    NASA Astrophysics Data System (ADS)

    Volavý, F.; Fišer, J.; Nöske, I.

    2013-04-01

    This paper deals with the prediction of the air temperature in the aircraft cabin by means of Computational Fluid Dynamics. The simulations are performed on the CFD model which is based on geometry and cabin interior arrangement of the Flight Test Facility (FTF) located at Fraunhofer IBP, Germany. The experimental test flights under three different cabin temperatures were done in FTF and the various data were gathered during these flights. Air temperature in the cabin was measured on probes located near feet, torso and head of each passenger and also surface temperature and air temperature distributed from inlets were measured. The data were firstly analysed in order to obtain boundary conditions for cabin surfaces and inlets. Then the results of air temperature from the simulations were compared with measured data. The suitability and accuracy of the CFD approach for temperature prediction is discussed.

  16. A study of the growth and decay of cigarette smoke NOx in ambient air under controlled conditions

    SciTech Connect

    Rickert, W.S.; Robinson, J.C. ); Collishaw, N.E. )

    1987-01-01

    The amount of NO{sub 2} and NO produced by the machine smoking of cigarettes was determined for 15 commercial Canadian brands. Average yield of NO was 1.44 {mu}moles or about 13% of the average reported for American cigarettes. Levels of NO{sub 2} were all less than 12% of NO and were probably due to the oxidation of NO. In order to assess the contribution of tobacco smoke to levels of NO in ambient air, 5 brands of cigarettes were smoked in a 27 cubic meter controlled environment room. Ventilation conditions were either 2.5 or 5.0 air changes per hour (ACH) and each experiment was replicated 3 times for a total of 30 experiments. Ventilation rates of 0.3 and 1.5 ACH were also selected in a second series of experiments in which only one brand of cigarette was smoked. Least squares estimates for the effective ventilation rates were obtained in the usual manner after linearizing the decay portion of the NO time curve. In each of the experiments, the regression explained at least 95% of the variation in the levels of NO with time. Loss of NO due to factors other than ventilation appeared to be constant within experimental error and averaged 2.22 ACH. Equilibrium values for NO were grossly underestimated when results from currently accepted procedures for smoke analysis were used in modeling the growth and decay of NO. Goodness-of-fit was improved when equilibrium values were estimated based on observed levels in ambient air.

  17. 10. CONTROL ROOM INTERIOR. Looking into southwest corner. CONTROL ROOM ...

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

    10. CONTROL ROOM INTERIOR. Looking into southwest corner. CONTROL ROOM INTERIOR, SHOWING ESCAPE HATCH. Looking north along east wall. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Instrumentation & Control Building, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

  18. Volatile organic compounds associated with microbial growth in automobile air conditioning systems.

    PubMed

    Rose, L J; Simmons, R B; Crow, S A; Ahearn, D G

    2000-09-01

    Volatile organic compounds from Penicillium viridicatum and Methylobacterium mesophilicum growing on laboratory media and on component materials of automobile air conditioners were analyzed with gas chromatography and mass spectrometry. P. viridicatum produced compounds such as 4-methyl thiazole, terpenes and alcohols, whereas M. mesophilicum produced dimethyl disulfide, dimethyl trisulfide, and chlorophenol with growth on laboratory media. In comparison with laboratory media, fewer volatiles were detected from colonized foam insulation materials. Biofilms of M. mesophilicum on aluminum evaporator components produced mainly dimethyl disulfide. These biofilms, after inoculation with P. viridicatum, produced offensive smelling alcohols and esters such as 2-methyl propanol, 3-penten-2-ol, and the ethyl ester of butanoic acid. The moisture and substrates innate to the automobile air conditioning systems provided an environment suitable for microbial biofilm development and odor production. Reduction of retained moisture in the air conditioning system coupled with use of less susceptible or antimicrobial substrates are advised for remediation of the noxious odors. PMID:10915209

  19. Workplace and environmental air contaminant concentrations measured by open path Fourier transform infrared spectroscopy: a statistical process control technique to detect changes from normal operating conditions.

    PubMed

    Malachowski, M S; Levine, S P; Herrin, G; Spear, R C; Yost, M; Yi, Z

    1994-05-01

    Open path Fourier transform infrared (OP-FTIR) spectroscopy is a new air monitoring technique that can be used to measure concentrations of air contaminants in real or near-real time. OP-FTIR spectroscopy has been used to monitor workplace gas and vapor exposures, emissions from hazardous waste sites, and to track emissions along fence lines. This paper discusses a statistical process control technique that can be used with air monitoring data collected with an OP-FTIR spectrometer to detect departures from normal operating conditions in the workplace or along a fence line. Time series data, produced by plotting consecutive air sample concentrations in time, were analyzed. Autocorrelation in the time series data was removed by fitting dynamic models. Control charts were used with the residuals of the model fit data to determine if departures from defined normal operating conditions could be rapidly detected. Shewhart and exponentially weighted moving average (EWMA) control charts were evaluated for use with data collected under different room air flow and mixing conditions. Under rapidly changing conditions the Shewhart control chart was able to detect a leak in a simulated process area. The EWMA control chart was found to be more sensitive to drifts and slowly changing concentrations in air monitoring data. The time series and statistical process control techniques were also applied to data obtained during a field study at a chemical plant. A production area of an acrylonitrile, 1,3-butadiene, and styrene (ABS) polymer process was monitored in near-real time. Decision logics based on the time series and statistical process control technique introduced suggest several applications in workplace and environmental monitoring. These applications might include signaling of an alarm or warning, increasing levels of worker respiratory protection, or evacuation of a community, when gas and vapor concentrations are determined to be out-of-control. PMID:8012765

  20. [Study on air quality and pollution meteorology conditions of Guangzhou during the 2010 Asian games].

    PubMed

    Li, Ting-Yuan; Deng, Xue-Jiao; Fan, Shao-Jia; Wu, Dui; Li, Fei; Deng, Tao; Tan, Hao-Bo; Jiang, De-Hai

    2012-09-01

    Based on the monitoring data of NO2, O3, SO2, PM, visibility, regional air quality index (RAQI) and the atmospheric transport and diffusion data from Nov. 4, 2010 to Dec. 10, 2010 in Guangzhou area, the variations of air quality and meteorological conditions during the Guangzhou Asian Games were analyzed. It was found that, during the Asian Games, the air quality was better than the air quality before or after the Asian Games. The visibility was greater than the visibility before or after the Asian Games, while the concentrations of PM1 and PM2.5 were lower. The correlation coefficient between visibility and the concentrations of PM1, PM2.5 indicated anti-correlation relationships. Daily and hourly concentrations of NO2 and SO2 met the primary ambient air quality standards, whereas the daily concentration of PM10 and hourly concentration of O3 met the secondary ambient air quality standards. Pollutants had been well controlled during the Asian Games. The concentration of SO2 in Guangzhou was influenced by local sources and long distance transmission, while the concentration of NO2 was significantly influenced by local sources. The emissions of NO2, SO2 and PM10 surrounding Guangzhou had a trend to affect the concentrations in Guangzhou, but the situation of O3 was opposite, the relatively high concentration of O3 in Guangzhou had tendency to be transported to the surrounding areas. The pollution meteorology conditions in the period of Asian Games were better than the conditions before or after the Asian Games. The decrease in the concentrations during the Asian Games did not only benefit from the emission control by the government, but also from the good meteorological conditions. PMID:23243841

  1. Study of indoor radon levels in high-rise air-conditioned office buildings.

    PubMed

    Chao, C Y

    1999-12-01

    A series of measurements were conducted to study the indoor radon pollution in air-conditioned high-rise office buildings. Continuous monitoring of indoor radon levels in nine air-conditioned premises located in six office buildings in Hong Kong was conducted from August 1996 to February 1998. Each of the tests lasted for at least 48 hours. The measurement covered both day time monitoring while the air-conditioning was on and night time monitoring while the air-conditioning was off. The indoor radon level followed inversely the operation pattern of the mechanical ventilation systems in the buildings. During office hours when the mechanical ventilation was on, the indoor radon level decayed and after the mechanical ventilation was off during non-office hours, the radon level increased. The average indoor radon level during office hours on the nine premises varied from 87 Bq/m3 to 296 Bq/m3, and the indoor averaged radon levels over both day time and night time periods without mechanical ventilation were about 25 percent higher. The air infiltration rate and the radon emission characteristics from the building materials were estimated from the radon build-up curves which were observed after the mechanical ventilation was off. The radon decay curve observed after the mechanical ventilation system was turned on was used to calculate the total fresh air intake rate. Average radon emanation rates of the building materials in the six buildings varied from 0.0019 to 0.0033 Bq/m2s. It has been found that building infiltration rate accounted for about 10-30 percent of the total building ventilation rate in the buildings depending on building tightness. PMID:10633952

  2. 24 CFR 3280.813 - Outdoor outlets, fixtures, air-conditioning equipment, etc.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 5 2012-04-01 2012-04-01 false Outdoor outlets, fixtures, air-conditioning equipment, etc. 3280.813 Section 3280.813 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND...

  3. Geothermal as a heat sink application for raising air conditioning efficency

    NASA Astrophysics Data System (ADS)

    Ibrahim, Hesham Safwat Osman Mohamed

    2016-04-01

    Objective: Geothermal applications in heating, ventilation, air-conditioning is a US technology for more than 30 years old ,which saves more than 30% average energy cost than the traditional air-conditioning systems systems. Applying this technology in Middle East and African countries would be very feasible specially in Egypt specially as it suffers Electric crisis --The temperature of the condensers and the heat rejecting equipment is much higher than the Egyptian land at different depth which is a great advantages, and must be measured, recorded, and studied accurately -The Far goal of the proposal is to construct from soil analysis a temperature gradient map for Egypt and , African countries on different depth till 100 m which is still unclear nowadays and must be measured and recorded in databases through researches - The main model of the research is to study the heat transfer gradient through the ground earth borehole,grout,high density polyethylene pipes , and water inlet temperature which affect the electric efficiency of the ground source heat pump air conditioning unit Impact on the Region: Such research result will contribute widely in Energy saving sector specially the air conditioning sector in Egypt and the African countries which consumes more than 30% of the electric consumption of the total consumption . and encouraging Green systems such Geothermal to be applied

  4. Refrigeration and Air Conditioning Mechanic: Apprenticeship Course Outline. Apprenticeship and Industry Training. 1411.2

    ERIC Educational Resources Information Center

    Alberta Advanced Education and Technology, 2011

    2011-01-01

    The graduate of the Refrigeration and Air Conditioning Mechanic apprenticeship training is a journeyman who will: (1) supervise, train and coach apprentices; (2) use and maintain hand and power tools to the standards of competency and safety required in the trade; (3) have a thorough knowledge of the principle components of refrigeration systems,…

  5. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... approvals will be granted, the Administrator will consider data showing how well the simulation matches environmental cell test data for the range of vehicles to be covered by the simulation including items such...

  6. 40 CFR 86.162-03 - Approval of alternative air conditioning test simulations.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... initiative, the Administrator will approve a simulation of the environmental cell for air conditioning test... approvals will be granted, the Administrator will consider data showing how well the simulation matches environmental cell test data for the range of vehicles to be covered by the simulation including items such...

  7. Introduction to Heating, Ventilation and Air Conditioning (HVAC). Instructor Edition. Introduction to Construction Series.

    ERIC Educational Resources Information Center

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This instructor's guide contains the materials required to teach a competency-based introductory course in heating, ventilating, and air conditioning (HVAC) to students who have chosen to explore careers in construction. It contains three units: HVAC materials, HVAC tools, and applied skills. Each instructional unit includes some or all of the…

  8. Getting Down to Business: Air Conditioning and Heating Service, Module 36. [Student Guide]. Entrepreneurship Training Components.

    ERIC Educational Resources Information Center

    Sanderson, Barbara

    This module on owning and operating an air conditioning and heating service is one of 36 in a series on entrepreneurship. The introduction tells the student what topics will be covered and suggests other modules to read in related occupations. Each unit includes student goals, a case study, and a discussion of the unit subject matter. Learning…

  9. Environmental Control System Installer/Servicer (Residential Air Conditioning Mechanic). V-TECS Guide.

    ERIC Educational Resources Information Center

    Meyer, Calvin F.; Benson, Robert T.

    This guide provides job relevant tasks, performance objectives, performance guides, resources, learning activitites, evaluation standards, and achievement testing in the occupation of environmental control system installer/servicer (residential air conditioning mechanic). It is designed to be used with any chosen teaching method. The course…

  10. Technology evaluation of heating, ventilation, and air conditioning for MIUS application

    NASA Technical Reports Server (NTRS)

    Gill, W. L.; Keough, M. B.; Rippey, J. O.

    1974-01-01

    Potential ways of providing heating, ventilation, and air conditioning for a building complex serviced by a modular integrated utility system (MIUS) are examined. Literature surveys were conducted to investigate both conventional and unusual systems to serve this purpose. The advantages and disadvantages of the systems most compatible with MIUS are discussed.

  11. PIC (PRODUCTS OF INCOMPLETE COMBUSTION) FORMATION UNDER PYROLYTIC AND STARVED AIR CONDITIONS

    EPA Science Inventory

    A comprehensive program of laboratory studies based on the non-flame mode of thermal decomposition produced much data on PIC (Products of Incomplete Combustion) formation, primarily under pyrolytic and starved air conditions. Most significantly, laboratory results from non-flame ...

  12. Instructional Guide for Air Conditioning and Refrigeration. V & TECC Curriculum Guide.

    ERIC Educational Resources Information Center

    Duenk, Lester G.; And Others

    This trade and industrial curriculum guide is intended for use in vocational programs that prepare students to enter the air conditioning/refrigeration field. The introductory section provides a statement of philosophy, objectives, block time schedule, and recommended facilities and equipment. Following the introductory section, eighteen blocks of…

  13. Refrigeration and Air Conditioning Equipment, 11-9. Military Curriculum Materials for Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This military-developed text consists of three blocks of instructional materials for use by those studying to become refrigeration and air conditioning specialists. Covered in the individual course blocks are the following topics: refrigeration and trouble analysis, thermodynamics, and principles of refrigeration; major components and domestic and…

  14. Military Curricula for Vocational & Technical Education. Refrigeration & Air Conditioning Specialist, Blocks I-II.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This plan of instruction, study guides, workbooks, and programmed texts for a secondary-postsecondary-level course in refrigeration and air conditioning are one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. It is the first section of a…

  15. Heating, Air Conditioning and Refrigeration. Vocational Education Curriculum Guide. Industrial and Technical Education.

    ERIC Educational Resources Information Center

    West Virginia State Vocational Curriculum Lab., Cedar Lakes.

    This curriculum guide contains 17 units that provides the basic curriculum components required to develop lesson plans for the heating, air conditioning, and refrigeration curriculum. The guide is not intended to be a complete, self-contained curriculum, but instead provides the teacher with a number of informational items related to the learning…

  16. Heating, Ventilation, Air-conditioning, and Refrigeration. Ohio's Competency Analysis Profile.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Vocational Instructional Materials Lab.

    Developed through a modified DACUM (Developing a Curriculum) process involving business, industry, labor, and community agency representatives in Ohio, this document is a comprehensive and verified employer competency profile for heating, ventilation, air conditioning, and refrigeration occupations. The list contains units (with and without…

  17. Military Curricula for Vocational & Technical Education. Refrigeration and Air Conditioning Specialist, Blocks VI-IX.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. National Center for Research in Vocational Education.

    This plan of instruction, study guides, and workbooks for a secondary-postsecondary-level course in refrigeration and air conditioning are one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. It is the third section of a three-part course (see…

  18. Introduction to Heating, Ventilation and Air Conditioning (HVAC). Introduction to Construction Series. Instructor Edition.

    ERIC Educational Resources Information Center

    Associated General Contractors of America, Washington, DC.

    This module on introductory heating, ventilating, and air conditioning (HVAC) is one of a series of modules designed to teach basic skills necessary for entry-level employment in this field. The module contains four instructional units that cover the following topics: (1) HVAC materials; (2) HVAC tools; (3) HVAC layout; and (4) HVAC basic skills.…

  19. A laser Doppler system for the remote sensing of boundary layer winds in clear air conditions

    NASA Technical Reports Server (NTRS)

    Lawrence, T. R.; Krause, M. C.; Craven, C. E.; Morrison, L. K.; Thomson, J. A. L.; Cliff, W. C.; Huffaker, R. M.

    1975-01-01

    The system discussed uses a laser Doppler radar in combination with a velocity azimuth display mode of scanning to determine the three-dimensional wind field in the atmospheric boundary layer. An attractive feature of this CW monostatic system is that the ambient aerosol provides a 'sufficient' scattering target to permit operation under clear air conditions. Spatial resolution is achieved by focusing.

  20. Heating, Air Conditioning and Refrigeration Curriculum Guide. Michigan Trade and Industrial Education.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for heating, air conditioning, and refrigeration is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a career ladder, a matrix relating duty/task numbers to job titles, and a…

  1. V-TECS Guide for Automobile Air Conditioning and Electrical System Technician.

    ERIC Educational Resources Information Center

    Meyer, Calvin F.; Benson, Robert T.

    This curriculum guide provides an outline for an eight-unit course to train automobile air conditioning and electrical system technicians. Each unit focuses on a duty that is composed of a number of performance objectives. For each objective, these materials are provided: a task, a standard of performance of task, source of standard, conditions…

  2. 14 CFR 203.5 - Compliance as condition on operations in air transportation.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Compliance as condition on operations in air transportation. 203.5 Section 203.5 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS WAIVER OF WARSAW CONVENTION LIABILITY LIMITS...

  3. A GUIDE FOR USE IN DEVELOPING TRAINING PROGRAMS IN VOCATIONAL REFRIGERATION AND AIR CONDITIONING (DOMESTIC).

    ERIC Educational Resources Information Center

    Mississippi State Univ., State College.

    THE MATERIAL IN THIS CURRICULUM GUIDE WAS DEVELOPED TO HELP THE INSTRUCTOR TRAIN STUDENTS TO MEET THE ENTRY REQUIREMENTS FOR REFRIGERATION AND AIR CONDITIONING TRADESMEN. EXPERIENCED TEACHERS DETERMINED OBJECTIVES, DEVELOPED A JOB ANALYSIS, IDENTIFIED THE INSTRUCTIONAL CONTENT, SEQUENCED LEARNING EXPERIENCES, AND SELECTED PERTINENT LITERATURE. THE…

  4. Non-Print Instructional Materials for the Air Conditioning and Refrigeration Maintenance Field.

    ERIC Educational Resources Information Center

    Golitko, Raymond L., Ed.; And Others

    This catalog contains a listing of air conditioning/refrigeration maintenance audiovisual training materials from the Houston Community College System library media collection. The material is organized by subject heading. The media titles are listed in alphabetical order by title under each subject heading in the catalog. The citation for each…

  5. LINKING ETA MODEL WITH THE COMMUNITY MULTISCALE AIR QUALITY (CMAQ) MODELING SYSTEM: OZONE BOUNDARY CONDITIONS

    EPA Science Inventory

    A prototype surface ozone concentration forecasting model system for the Eastern U.S. has been developed. The model system is consisting of a regional meteorological and a regional air quality model. It demonstrated a strong prediction dependence on its ozone boundary conditions....

  6. Design of a test facility for gas-fired desiccant-based air conditioning systems

    SciTech Connect

    Jalalzadeh-Azar, A.A.; Steele, W.G.; Hodge, B.K.

    1996-12-31

    The design of a facility for testing desiccant-based air conditioning systems is presented. The determination of the performance parameters of desiccant systems is discussed including moisture removal capacity, latent and total cooling capacities, and efficiency indexes. The appropriate procedures and key measurements for determining these parameters are identified using uncertainty analysis.

  7. Urban air quality assessment using monitoring data of fractionized aerosol samples, chemometrics and meteorological conditions.

    PubMed

    Yotova, Galina I; Tsitouridou, Roxani; Tsakovski, Stefan L; Simeonov, Vasil D

    2016-01-01

    The present article deals with assessment of urban air by using monitoring data for 10 different aerosol fractions (0.015-16 μm) collected at a typical urban site in City of Thessaloniki, Greece. The data set was subject to multivariate statistical analysis (cluster analysis and principal components analysis) and, additionally, to HYSPLIT back trajectory modeling in order to assess in a better way the impact of the weather conditions on the pollution sources identified. A specific element of the study is the effort to clarify the role of outliers in the data set. The reason for the appearance of outliers is strongly related to the atmospheric condition on the particular sampling days leading to enhanced concentration of pollutants (secondary emissions, sea sprays, road and soil dust, combustion processes) especially for ultra fine and coarse particles. It is also shown that three major sources affect the urban air quality of the location studied-sea sprays, mineral dust and anthropogenic influences (agricultural activity, combustion processes, and industrial sources). The level of impact is related to certain extent to the aerosol fraction size. The assessment of the meteorological conditions leads to defining of four downwind patterns affecting the air quality (Pelagic, Western and Central Europe, Eastern and Northeastern Europe and Africa and Southern Europe). Thus, the present study offers a complete urban air assessment taking into account the weather conditions, pollution sources and aerosol fractioning. PMID:26942452

  8. VESL for Heating and Air Conditioning: A Competency-based Curriculum Guide. Project OSCAER.

    ERIC Educational Resources Information Center

    Lopez-Valadez, Jeanne, Ed.; Pankratz, David, Ed.

    This guide is intended for vocational educators developing the vocational English as a second language (VESL) component of a course in heating and air conditioning. The introductory section examines assumptions about second language learning and instruction and VESL classes, local adaptations of the curriculum, and sample VESL lessons. The chapter…

  9. Principles of Refrigeration. Automotive Mechanics. Air Conditioning. Instructor's Guide [and] Student Guide.

    ERIC Educational Resources Information Center

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automobile air conditioning, consists of a student guide and an instructor guide dealing with the principles of refrigeration. Covered in the module are defining the term heat, defining the term British Thermal Unit (BTU), defining the term latent heat, listing…

  10. Heating, Ventilation, Air Conditioning. Resource Manual for Custodial Training Course #3.

    ERIC Educational Resources Information Center

    Florida State Dept. of Education, Tallahassee. School Plant Management Section.

    Intended as a manual to provide school custodians with some understanding of basic functions of heating, ventilating, and air conditioning equipment for safe, efficient operation. Contains general rules and specifications for providing custodians with a more complete awareness of their equipment and the field of "Climate Control" within the…

  11. Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop

    SciTech Connect

    Not Available

    1994-09-01

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  12. An Investigation of Energy Consumption and Cost in Large Air-Conditioned Buildings. An Interim Report.

    ERIC Educational Resources Information Center

    Milbank, N. O.

    Two similarly large buildings and air conditioning systems are comparatively analyzed as to energy consumption, costs, and inefficiency during certain measured periods of time. Building design and velocity systems are compared to heating, cooling, lighting and distribution capabilities. Energy requirements for pumps, fans and lighting are found to…

  13. Hygiene guideline for the planning, installation, and operation of ventilation and air-conditioning systems in health-care settings - Guideline of the German Society for Hospital Hygiene (DGKH).

    PubMed

    Külpmann, Rüdiger; Christiansen, Bärbel; Kramer, Axel; Lüderitz, Peter; Pitten, Frank-Albert; Wille, Frank; Zastrow, Klaus-Dieter; Lemm, Friederike; Sommer, Regina; Halabi, Milo

    2016-01-01

    Since the publication of the first "Hospital Hygiene Guideline for the implementation and operation of air conditioning systems (HVAC systems) in hospitals" (http://www.krankenhaushygiene.de/informationen/fachinformationen/leitlinien/12) in 2002, it was necessary due to the increase in knowledge, new regulations, improved air-conditioning systems and advanced test methods to revise the guideline. Based on the description of the basic features of ventilation concepts, its hygienic test and the usage-based requirements for ventilation, the DGKH section "Ventilation and air conditioning technology" attempts to provide answers for the major air quality issues in the planning, design and the hygienically safe operation of HVAC systems in rooms of health care. PMID:26958457

  14. Hygiene guideline for the planning, installation, and operation of ventilation and air-conditioning systems in health-care settings – Guideline of the German Society for Hospital Hygiene (DGKH)

    PubMed Central

    Külpmann, Rüdiger; Christiansen, Bärbel; Kramer, Axel; Lüderitz, Peter; Pitten, Frank-Albert; Wille, Frank; Zastrow, Klaus-Dieter; Lemm, Friederike; Sommer, Regina; Halabi, Milo

    2016-01-01

    Since the publication of the first “Hospital Hygiene Guideline for the implementation and operation of air conditioning systems (HVAC systems) in hospitals” (http://www.krankenhaushygiene.de/informationen/fachinformationen/leitlinien/12) in 2002, it was necessary due to the increase in knowledge, new regulations, improved air-conditioning systems and advanced test methods to revise the guideline. Based on the description of the basic features of ventilation concepts, its hygienic test and the usage-based requirements for ventilation, the DGKH section “Ventilation and air conditioning technology” attempts to provide answers for the major air quality issues in the planning, design and the hygienically safe operation of HVAC systems in rooms of health care. PMID:26958457

  15. Statistical modeling of urban air temperature distributions under different synoptic conditions

    NASA Astrophysics Data System (ADS)

    Beck, Christoph; Breitner, Susanne; Cyrys, Josef; Hald, Cornelius; Hartz, Uwe; Jacobeit, Jucundus; Richter, Katja; Schneider, Alexandra; Wolf, Kathrin

    2015-04-01

    Within urban areas air temperature may vary distinctly between different locations. These intra-urban air temperature variations partly reach magnitudes that are relevant with respect to human thermal comfort. Therefore and furthermore taking into account potential interrelations with other health related environmental factors (e.g. air quality) it is important to estimate spatial patterns of intra-urban air temperature distributions that may be incorporated into urban planning processes. In this contribution we present an approach to estimate spatial temperature distributions in the urban area of Augsburg (Germany) by means of statistical modeling. At 36 locations in the urban area of Augsburg air temperatures are measured with high temporal resolution (4 min.) since December 2012. These 36 locations represent different typical urban land use characteristics in terms of varying percentage coverages of different land cover categories (e.g. impervious, built-up, vegetated). Percentage coverages of these land cover categories have been extracted from different sources (Open Street Map, European Urban Atlas, Urban Morphological Zones) for regular grids of varying size (50, 100, 200 meter horizonal resolution) for the urban area of Augsburg. It is well known from numerous studies that land use characteristics have a distinct influence on air temperature and as well other climatic variables at a certain location. Therefore air temperatures at the 36 locations are modeled utilizing land use characteristics (percentage coverages of land cover categories) as predictor variables in Stepwise Multiple Regression models and in Random Forest based model approaches. After model evaluation via cross-validation appropriate statistical models are applied to gridded land use data to derive spatial urban air temperature distributions. Varying models are tested and applied for different seasons and times of the day and also for different synoptic conditions (e.g. clear and calm

  16. Performance and evaluation of gas engine driven rooftop air conditioning equipment at the Willow Grove (PA) Naval Air Station

    SciTech Connect

    Armstrong, P.R.; Conover, D.R.

    1993-05-01

    In a field evaluation conducted for the US Department of Energy (DOE) Office of Federal Energy Management Program (FEMP), the Pacific Northwest Laboratory (PNL) examined the performance of a new US energy-related technology under the FEMP Test Bed Demonstration Program. The technology was a 15-ton natural gas engine driven roof top air conditioning unit. Two such units were installed on a naval retail building to provide space conditioning to the building. Under the Test Bed Demonstration Program, private and public sector interests are focused to support the installation and evaluation of new US technologies in the federal sector. Participating in this effort under a Cooperative Research and Development Agreement (CRADA) with DOE were the American Gas Cooling Center, Philadelphia Electric Company, Thermo King Corporation, and the US Naval Air Station at Willow Grove, Pennsylvania. Equipment operating and service data as well as building interior and exterior conditions were secured for the 1992 cooling season. Based on a computer assessment of the building using standard weather data, a comparison was made with the energy and operating costs associated with the previous space conditioning system. Based on performance during the 1992 cooling season and adjusted to a normal weather year, the technology will save the site $6,000/yr in purchased energy costs. An additional $9,000 in savings due to electricity demand ratchet charge reductions will also be realized. Detailed information on the technology, the installation, and the results of the technology test are provided to illustrate the advantages to the federal sector of using this technology. A history of the CRADA development process is also reported.

  17. Experimental Study on Ultrafine Particle Removal Performance of Portable Air Cleaners with Different Filters in an Office Room.

    PubMed

    Ma, Huan; Shen, Henggen; Shui, Tiantian; Li, Qing; Zhou, Liuke

    2016-01-01

    Size- and time-dependent aerodynamic behaviors of indoor particles, including PM1.0, were evaluated in a school office in order to test the performance of air-cleaning devices using different filters. In-situ real-time measurements were taken using an optical particle counter. The filtration characteristics of filter media, including single-pass efficiency, volume and effectiveness, were evaluated and analyzed. The electret filter (EE) medium shows better initial removal efficiency than the high efficiency (HE) medium in the 0.3-3.5 μm particle size range, while under the same face velocity, the filtration resistance of the HE medium is several times higher than that of the EE medium. During service life testing, the efficiency of the EE medium decreased to 60% with a total purifying air flow of 25 × 10⁴ m³/m². The resistance curve rose slightly before the efficiency reached the bottom, and then increased almost exponentially. The single-pass efficiency of portable air cleaner (PAC) with the pre-filter (PR) or the active carbon granule filter (CF) was relatively poor. While PAC with the pre-filter and the high efficiency filter (PR&HE) showed maximum single-pass efficiency for PM1.0 (88.6%), PAC with the HE was the most effective at removing PM1.0. The enhancement of PR with HE and electret filters augmented the single-pass efficiency, but lessened the airflow rate and effectiveness. Combined with PR, the decay constant of large-sized particles could be greater than for PACs without PR. Without regard to the lifetime, the electret filters performed better with respect to resource saving and purification improvement. A most penetrating particle size range (MPPS: 0.4-0.65 μm) exists in both HE and electret filters; the MPPS tends to become larger after HE and electret filters are combined with PR. These results serve to provide a better understanding of the indoor particle removal performance of PACs when combined with different kinds of filters in school

  18. Experimental Study on Ultrafine Particle Removal Performance of Portable Air Cleaners with Different Filters in an Office Room

    PubMed Central

    Ma, Huan; Shen, Henggen; Shui, Tiantian; Li, Qing; Zhou, Liuke

    2016-01-01

    Size- and time-dependent aerodynamic behaviors of indoor particles, including PM1.0, were evaluated in a school office in order to test the performance of air-cleaning devices using different filters. In-situ real-time measurements were taken using an optical particle counter. The filtration characteristics of filter media, including single-pass efficiency, volume and effectiveness, were evaluated and analyzed. The electret filter (EE) medium shows better initial removal efficiency than the high efficiency (HE) medium in the 0.3–3.5 μm particle size range, while under the same face velocity, the filtration resistance of the HE medium is several times higher than that of the EE medium. During service life testing, the efficiency of the EE medium decreased to 60% with a total purifying air flow of 25 × 104 m3/m2. The resistance curve rose slightly before the efficiency reached the bottom, and then increased almost exponentially. The single-pass efficiency of portable air cleaner (PAC) with the pre-filter (PR) or the active carbon granule filter (CF) was relatively poor. While PAC with the pre-filter and the high efficiency filter (PR&HE) showed maximum single-pass efficiency for PM1.0 (88.6%), PAC with the HE was the most effective at removing PM1.0. The enhancement of PR with HE and electret filters augmented the single-pass efficiency, but lessened the airflow rate and effectiveness. Combined with PR, the decay constant of large-sized particles could be greater than for PACs without PR. Without regard to the lifetime, the electret filters performed better with respect to resource saving and purification improvement. A most penetrating particle size range (MPPS: 0.4–0.65 μm) exists in both HE and electret filters; the MPPS tends to become larger after HE and electret filters are combined with PR. These results serve to provide a better understanding of the indoor particle removal performance of PACs when combined with different kinds of filters in school

  19. Total environmental warming impact (TEWI) calculations for alternative automative air-conditioning systems

    SciTech Connect

    Sand, J.R.; Fischer, S.K.

    1997-01-01

    The Montreal Protocol phase-out of chlorofluorocarbons (CFCs) has required manufacturers to develop refrigeration and air-conditioning systems that use refrigerants that can not damage stratospheric ozone. Most refrigeration industries have adapted their designs to use hydrochlorofluorocarbon (HCFC) or hydrofluorocarbon (HFC) refrigerants; new automobile air- conditioning systems use HFC-134a. These industries are now being affected by scientific investigations of greenhouse warming and questions about the effects of refrigerants on global warming. Automobile air-conditioning has three separate impacts on global warming; (1) the effects of refrigerant inadvertently released to the atmosphere from accidents, servicing, and leakage; (2) the efficiency of the cooling equipment (due to the emission of C0{sub 2} from burning fuel to power the system); and (3) the emission of C0{sub 2} from burning fuel to transport the system. The Total Equivalent Warming Impact (TEWI) is an index that should be used to compare the global warming effects of alternative air-conditioning systems because it includes these contributions from the refrigerant, cooling efficiency, and weight. This paper compares the TEWI of current air-conditioning systems using HFC-134a with that of transcritical vapor compression system using carbon dioxide and systems using flammable refrigerants with secondary heat transfer loops. Results are found to depend on both climate and projected efficiency of C0{sub 2}systems. Performance data on manufacturing prototype systems are needed to verify the potential reductions in TEWI. Extensive field testing is also required to determine the performance, reliability, and ``serviceability`` of each alternative to HFC-134a to establish whether the potential reduction of TEWI can be achieved in a viable consumer product.

  20. Waking the sleeping giant: Introducing new heat exchanger technology into the residential air-conditioning marketplace

    SciTech Connect

    Chapp, T.; Voss, M.; Stephens, C.

    1998-07-01

    The Air Conditioning Industry has made tremendous strides in improvements to the energy efficiency and reliability of its product offerings over the past 40 years. These improvement can be attributed to enhancements of components, optimization of the energy cycle, and modernized and refined manufacturing techniques. During this same period, energy consumption for space cooling has grown significantly. In January of 1992, the minimum efficiency requirement for central air conditioning equipment was raised to 10 SEER. This efficiency level is likely to increase further under the auspices of the National Appliance Energy Conservation Act (NAECA). A new type of heat exchanger was developed for air conditioning equipment by Modine Manufacturing Company in the early 1990's. Despite significant advantages in terms of energy efficiency, dehumidification, durability, and refrigerant charge there has been little interest expressed by the air conditioning industry. A cooperative effort between Modine, various utilities, and several state energy offices has been organized to test and demonstrate the viability of this heat exchanger design throughout the nation. This paper will review the fundamentals of heat exchanger design and document this simple, yet novel technology. These experiences involving equipment retrofits have been documented with respect to the performance potential of air conditioning system constructed with PF{trademark} Heat Exchangers (generically referred to as microchannel heat exchangers) from both an energy efficiency as well as a comfort perspective. The paper will also detail the current plan to introduce 16 to 24 systems into an extended field test throughout the US which commenced in the Fall of 1997.

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

    SciTech Connect

    Thomas, John F; Huff, Shean P; West, Brian H; Norman, Kevin M

    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. Four 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.

  2. Influence of indoor air conditions on radon concentration in a detached house.

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

    Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden. In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach. The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50-60%. PMID:23159846

  3. Selective growth and integration of silver nanoparticles on silver nanowires at room conditions for transparent nano-network electrode.

    PubMed

    Lu, Haifei; Zhang, Di; Ren, Xingang; Liu, Jian; Choy, Wallace C H

    2014-10-28

    Recently, metal nanowires have received great research interests due to their potential as next-generation flexible transparent electrodes. While great efforts have been devoted to develop enabling nanowire electrodes, reduced contact resistance of the metal nanowires and improved electrical stability under continuous bias operation are key issues for practical applications. Here, we propose and demonstrate an approach through a low-cost, robust, room temperature and room atmosphere process to fabricate a conductive silver nano-network comprising silver nanowires and silver nanoparticles. To be more specific, silver nanoparticles are selectively grown and chemically integrated in situ at the junction where silver nanowires meet. The site-selective growth of silver nanoparticles is achieved by a plasmon-induced chemical reaction using a simple light source at very low optical power density. Compared to silver nanowire electrodes without chemical treatment, we observe tremendous conductivity improvement in our silver nano-networks, while the loss in optical transmission is negligible. Furthermore, the silver nano-networks exhibit superior electrical stability under continuous bias operation compared to silver nanowire electrodes formed by thermal annealing. Interestingly, our silver nano-network is readily peeled off in water, which can be easily transferred to other substrates and devices for versatile applications. We demonstrate the feasibly transferrable silver conductive nano-network as the top electrode in organic solar cells. Consequently, the transparent and conductive silver nano-networks formed by our approach would be an excellent candidate for various applications in optoelectronics and electronics. PMID:25285984

  4. The effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions

    NASA Astrophysics Data System (ADS)

    Aydan, Ö.; Ito, T.

    2015-11-01

    It is well known that some sinkholes or subsidence take place from time to time in the areas where abandoned room and pillar type mines exist. The author has been involved with the stability of abandoned mines beneath urbanized residential areas in Tokai region and there is a great concern about the stability of these abandoned mines during large earthquakes as well as in the long term. The 2003 Miyagi Hokubu and 2011 Great East Japan earthquakes caused great damage to abandoned mines and resulted in many collapses. The author presents the effect of the depth and groundwater on the formation of sinkholes or ground subsidence associated with abandoned room and pillar lignite mines under static and dynamic conditions and discusses the implications on the areas above abandoned lignite mines in this paper.

  5. Solar Absorption Refrigeration System for Air-Conditioning of a Classroom Building in Northern India

    NASA Astrophysics Data System (ADS)

    Agrawal, Tanmay; Varun; Kumar, Anoop

    2015-10-01

    Air-conditioning is a basic tool to provide human thermal comfort in a building space. The primary aim of the present work is to design an air-conditioning system based on vapour absorption cycle that utilizes a renewable energy source for its operation. The building under consideration is a classroom of dimensions 18.5 m × 13 m × 4.5 m located in Hamirpur district of Himachal Pradesh in India. For this purpose, cooling load of the building was calculated first by using cooling load temperature difference method to estimate cooling capacity of the air-conditioning system. Coefficient of performance of the refrigeration system was computed for various values of strong and weak solution concentration. In this work, a solar collector is also designed to provide required amount of heat energy by the absorption system. This heat energy is taken from solar energy which makes this system eco-friendly and sustainable. A computer program was written in MATLAB to calculate the design parameters. Results were obtained for various values of solution concentrations throughout the year. Cost analysis has also been carried out to compare absorption refrigeration system with conventional vapour compression cycle based air-conditioners.

  6. Enhanced effect of water vapor on complete oxidation of formaldehyde in air with ozone over MnOx catalysts at room temperature.

    PubMed

    Zhao, De-Zhi; Shi, Chuan; Li, Xiao-Song; Zhu, Ai-Min; Jang, Ben W-L

    2012-11-15

    At room temperature, the enhanced effect of water vapor on ozone catalytic oxidation (OZCO) of formaldehyde to CO2 over MnOx catalysts and the reaction stability was reported. In a dry air stream, only below 20% of formaldehyde could be oxidized into CO2 by O3. In humid air streams (RH≥55%), ∼100% of formaldehyde were oxidized into CO2 by O3 and the reaction stability was significantly enhanced. Meanwhile, in situ Diffuse Reflectance Infrared Fourier Transform (DRIFT) spectra of OZCO of HCHO demonstrate that the amount of both monodentate and bidentate carbonate species on MnOx, in the dry stream, increased gradually with time on stream (TOS). However, in the humid stream, almost no accumulation of carbonate species on the catalysts was observed. To clarify the enhanced mechanism, formaldehyde surface reactions and CO2 adsorption/desorption on the fresh, O3 and O3+H2O treated MnOx catalysts were examined comparatively. PMID:23021101

  7. Talaromyces rubrifaciens, a new species discovered from heating, ventilation and air conditioning systems in China.

    PubMed

    Luo, Yi; Lu, Xiaohong; Bi, Wu; Liu, Fan; Gao, Weiwei

    2016-01-01

    A new Talaromyces species, T. rubrifaciens, was isolated from supply air outlets of heating, ventilation and air conditioning (HVAC) systems in three kinds of public building in Beijing and Nanjing, China. Morphologically it exhibits many characters of section Trachyspermi but is distinguished from other species of this section by restricted growth and broad and strictly biverticillate conidiophores. Phylogenetic analyses based on the internal transcribed spacer rDNA (ITS), β-tubulin (BenA), calmodulin (CaM) and RNA polymerase second largest subunit (RPB2) genes reveal that T. rubrifaciens is a distinct species in section Trachyspermi. PMID:27055570

  8. Fault tree analysis for exposure to refrigerants used for automotive air conditioning in the United States.

    PubMed

    Jetter, J J; Forte, R; Rubenstein, R

    2001-02-01

    A fault tree analysis was used to estimate the number of refrigerant exposures of automotive service technicians and vehicle occupants in the United States. Exposures of service technicians can occur when service equipment or automotive air-conditioning systems leak during servicing. The number of refrigerant exposures of service technicians was estimated to be 135,000 per year. Exposures of vehicle occupants can occur when refrigerant enters passenger compartments due to sudden leaks in air-conditioning systems, leaks following servicing, or leaks caused by collisions. The total number of exposures of vehicle occupants was estimated to be 3,600 per year. The largest number of exposures of vehicle occupants was estimated for leaks caused by collisions, and the second largest number of exposures was estimated for leaks following servicing. Estimates used in the fault tree analysis were based on a survey of automotive air-conditioning service shops, the best available data from the literature, and the engineering judgement of the authors and expert reviewers from the Society of Automotive Engineers Interior Climate Control Standards Committee. Exposure concentrations and durations were estimated and compared with toxicity data for refrigerants currently used in automotive air conditioners. Uncertainty was high for the estimated numbers of exposures, exposure concentrations, and exposure durations. Uncertainty could be reduced in the future by conducting more extensive surveys, measurements of refrigerant concentrations, and exposure monitoring. Nevertheless, the analysis indicated that the risk of exposure of service technicians and vehicle occupants is significant, and it is recommended that no refrigerant that is substantially more toxic than currently available substitutes be accepted for use in vehicle air-conditioning systems, absent a means of mitigating exposure. PMID:11332544

  9. Air Pollution modifies the association between successful and pathological aging throughout the frailty condition.

    PubMed

    Fougère, Bertrand; Vellas, Bruno; Billet, Sylvain; Martin, Perrine J; Gallucci, Maurizio; Cesari, Matteo

    2015-11-01

    The rapid growth in the number of older adults has many implications for public health, including the need to better understand the risks posed by environmental exposures. Aging leads to a decline and deterioration of functional properties at the cellular, tissue and organ level. This loss of functional properties yields to a loss of homeostasis and decreased adaptability to internal and external stress. Frailty is a geriatric syndrome characterized by weakness, weight loss, and low activity that is associated with adverse health outcomes. Frailty manifests as an age-related, biological vulnerability to stressors and decreased physiological reserves. Ambient air pollution exposure affects human health, and elderly people appear to be particularly susceptible to its adverse effects. The aim of this paper is to discuss the role of air pollution in the modulation of several biological mechanisms involved in aging. Evidence is presented on how air pollution can modify the bidirectional association between successful and pathological aging throughout the frailty conditions. PMID:26462883

  10. Maximum mixing times of methane and air under non-reacting and reacting conditions

    SciTech Connect

    Brasoveanu, D.; Gupta, A.K.

    1998-07-01

    Mixing times between methane and air under non-reacting or reacting conditions in the presence of rates of temperature and pressure and velocity gradients are examined using a mixing model based on the ideal gas law and the equation of continuity. The model is valid for low pressure combustors under non-reacting conditions. The model is also valid under reacting conditions for the fresh mixture which contains only trace amounts of combustion products. The effects of initial pressure, temperature and fluid composition on mixing time are also analyzed. In general, the exact mixing time has to be determined numerically. Nevertheless maximum values of mixing times can be determined analytically for a broad range of operational conditions. Results show that under both reacting and non-reacting conditions, the maximum mixing time is directly proportional to the initial pressure and temperature of mixture and inversely proportional to rates of pressure and temperature, and to velocity divergence. Mixing through fuel dispersion into the surrounding air is shown to be faster than via air penetration into the fuel flow. Rates of pressure of less than 1 atm/s acting along provide a mixing time in excess of one second which is unacceptably long for many applications, in particular gas turbine combustion. Rates of temperature produced by flame may provide mixing times shorter than 0.1 s. Mixing times of the order of a few milliseconds for efficient combustion and low emission, require high velocity gradients at the fuel-air boundary. Results show that enhanced mixing is achieved by combining temperature and velocity gradients. This analysis of mixing time is intended to provide important design guidelines for the development of high intensity, high efficiency and low emission combustors.

  11. Children's well-being at schools: Impact of climatic conditions and air pollution.

    PubMed

    Salthammer, Tunga; Uhde, Erik; Schripp, Tobias; Schieweck, Alexandra; Morawska, Lidia; Mazaheri, Mandana; Clifford, Sam; He, Congrong; Buonanno, Giorgio; Querol, Xavier; Viana, Mar; Kumar, Prashant

    2016-09-01

    Human civilization is currently facing two particular challenges: population growth with a strong trend towards urbanization and climate change. The latter is now no longer seriously questioned. The primary concern is to limit anthropogenic climate change and to adapt our societies to its effects. Schools are a key part of the structure of our societies. If future generations are to take control of the manifold global problems, we have to offer our children the best possible infrastructure for their education: not only in terms of the didactic concepts, but also with regard to the climatic conditions in the school environment. Between the ages of 6 and 19, children spend up to 8h a day in classrooms. The conditions are, however, often inacceptable and regardless of the geographic situation, all the current studies report similar problems: classrooms being too small for the high number of school children, poor ventilation concepts, considerable outdoor air pollution and strong sources of indoor air pollution. There have been discussions about a beneficial and healthy air quality in classrooms for many years now and in recent years extensive studies have been carried out worldwide. The problems have been clearly outlined on a scientific level and there are prudent and feasible concepts to improve the situation. The growing number of publications also highlights the importance of this subject. High carbon dioxide concentrations in classrooms, which indicate poor ventilation conditions, and the increasing particle matter in urban outdoor air have, in particular, been identified as primary causes of poor indoor air quality in schools. Despite this, the conditions in most schools continue to be in need of improvement. There are many reasons for this. In some cases, the local administrative bodies do not have the budgets required to address such concerns, in other cases regulations and laws stand in contradiction to the demands for better indoor air quality, and sometimes

  12. Low-Flow Liquid Desiccant Air-Conditioning: Demonstrated Performance and Cost Implications

    SciTech Connect

    Kozubal, E.; Herrmann, L.; Deru, M.; Clark, J.; Lowenstein, A.

    2014-09-01

    Cooling loads must be dramatically reduced when designing net-zero energy buildings or other highly efficient facilities. Advances in this area have focused primarily on reducing a building's sensible cooling loads by improving the envelope, integrating properly sized daylighting systems, adding exterior solar shading devices, and reducing internal heat gains. As sensible loads decrease, however, latent loads remain relatively constant, and thus become a greater fraction of the overall cooling requirement in highly efficient building designs, particularly in humid climates. This shift toward latent cooling is a challenge for heating, ventilation, and air-conditioning (HVAC) systems. Traditional systems typically dehumidify by first overcooling air below the dew-point temperature and then reheating it to an appropriate supply temperature, which requires an excessive amount of energy. Another dehumidification strategy incorporates solid desiccant rotors that remove water from air more efficiently; however, these systems are large and increase fan energy consumption due to the increased airside pressure drop of solid desiccant rotors. A third dehumidification strategy involves high flow liquid desiccant systems. These systems require a high maintenance separator to protect the air distribution system from corrosive desiccant droplet carryover and so are more commonly used in industrial applications and rarely in commercial buildings. Both solid desiccant systems and most high-flow liquid desiccant systems (if not internally cooled) add sensible energy which must later be removed to the air stream during dehumidification, through the release of sensible heat during the sorption process.

  13. Air conditioning impact on the dynamics of radon and its daughters concentration.

    PubMed

    Kozak, Krzysztof; Grządziel, Dominik; Połednik, Bernard; Mazur, Jadwiga; Dudzińska, Marzenna R; Mroczek, Mariusz

    2014-12-01

    Radon and its decay products are harmful pollutants present in indoor air and are responsible for the majority of the effective dose due to ionising radiation that people are naturally exposed to. The paper presents the results of the series of measurements of radon and its progeny (in unattached and attached fractions) as well as indoor air parameters: temperature, relative humidity, number and mass concentrations of fine aerosol particles. The measurements were carried out in the auditorium (lecture hall), which is an indoor air quality laboratory, in controlled conditions during two periods of time: when air conditioning (AC) was switched off (unoccupied auditorium) and when it was switched on (auditorium in normal use). The significant influence of AC and of students' presence on the dynamics of radon and its progeny was confirmed. A decrease in the mean value of radon and its attached progeny was found when AC was working. The mean value of radon equilibrium factor F was also lower when AC was working (0.49) than when it was off (0.61). The linear correlations were found between attached radon progeny concentration and particle number and mass concentration only when the AC was switched off. This research is being conducted with the aim to study the variability of radon equilibrium factor F which is essential to determine the effective dose due to radon and its progeny inhalation. PMID:24375376

  14. [The main ways of improvement of medical support of the Air Forces in modern conditions].

    PubMed

    Blaginin, A A; Grebeniuk, A N; Lizogub, I N

    2014-02-01

    Blaginin A.A., Grebenyuk A.N., Lizogub LN. - The main ways of improvement of medical support of the Air Forces in modern conditions. Aircrew conducting active hostilities suffers from the whole spectrum of factors and conditions of the combat situation. The main task for the medical service of the Air Force is to carry out preventive and curative action for aviation specialists who are responsible for the combat capability of aircraft formations. The medical service of the Air Force must have forces and facilities for planning, organization and implementation of the treatment of lightly wounded and sick aviation professionals with short periods of recovery, medical rehabilitation of aircrew qfter suffering injuries, diseases, sanatorium therapy of aircrew with partial failure of health, outpatient and inpatient medical examination aircrew - flight commissions, preventive rest of aviation specialists with symptoms of chronic fatigue. Should be trained aviation physicians, including both basic military medical education and in-depth study of the medical aspects of various fields of personnel of the Air Force. PMID:25046924

  15. Effect of green roofs on air temperature; measurement study of well-watered and dry conditions

    NASA Astrophysics Data System (ADS)

    Solcerova, Anna; van de Ven, Frans; Wang, Mengyu; van de Giesen, Nick

    2016-04-01

    Rapid urbanization and increasing number and duration of heat waves poses a need for understanding urban climate and ways to mitigate extremely high temperatures. One of repeatedly suggested and often investigated methods to moderate the so called urban heat island are green roofs. This study investigates several extensive green roofs in Utrecht (NL) and their effect on air temperature right above the roof surface. Air temperature was measured 15 and 30 cm above the roof surface and also in the substrate. We show that under normal condition is air above green roof, compared to white gravel roof, colder at night and warmer during day. This suggest that green roofs might help decrease air temperatures at night, when the urban heat island is strongest, but possibly contribute to high temperatures during daytime. We also measured situation when the green roofs wilted and dried out. Under such conditions green roof exhibits more similar behavior to conventional white gravel roof. Interestingly, pattern of soil temperature remains almost the same for both dry and well-prospering green roof, colder during day and warmer at night. As such, green roof works as a buffer of diurnal temperature changes.

  16. An efficient new automobile air-conditioning system based on CO{sub 2} vapor compression

    SciTech Connect

    Pettersen, J.

    1994-12-31

    A new, efficient, and environmentally safe automobile air-conditioning system based on carbon dioxide (CO{sub 2}) vapor compression has been developed. Although working pressures and component design are different, the basic principles are similar to those of current chlorofluorocarbon/hydrofluorocarbon (CFC/HFC) units. With the construction and testing of a laboratory prototype, it has been documented that the new system is highly competitive with current CFC-12 and HFC-134a units in terms of efficiency, capacity, cost, weight, and dimensions. The CO{sub 2} concept thus offers a solution to the environmental problem associated with automobile air conditioning and eliminates all uncertainties with respect to possible unforeseen effects from new refrigerant compounds. Further advantages of the natural fluid CO{sub 2} as a refrigerant are: no need for recycling or recovery, low cost of fluid, excellent availability, well-known properties, and more compact machinery and components.

  17. Characterization of Francisella species isolated from the cooling water of an air conditioning system.

    PubMed

    Gu, Quan; Li, Xunde; Qu, Pinghua; Hou, Shuiping; Li, Juntao; Atwill, Edward R; Chen, Shouyi

    2015-01-01

    Strains of Francisella spp. were isolated from cooling water from an air conditioning system in Guangzhou, China. These strains are Gram negative, coccobacilli, non-motile, oxidase negative, catalase negative, esterase and lipid esterase positive. In addition, these bacteria grow on cysteine-supplemented media at 20 °C to 40 °C with an optimal growth temperature of 30 °C. Analysis of 16S rRNA gene sequences revealed that these strains belong to the genus Francisella. Biochemical tests and phylogenetic and BLAST analyses of 16S rRNA, rpoB and sdhA genes indicated that one strain was very similar to Francisella philomiragia and that the other strains were identical or highly similar to the Francisella guangzhouensis sp. nov. strain 08HL01032 we previously described. Biochemical and molecular characteristics of these strains demonstrated that multiple Francisella species exist in air conditioning systems. PMID:26413079

  18. Energy Performance Comparison of Heating and Air Conditioning Systems for Multi-Family Residential Buildings

    SciTech Connect

    Wang, Weimin; Zhang, Jian; Jiang, Wei; Liu, Bing

    2011-07-31

    The type of heating, ventilation and air conditioning (HVAC) system has a large impact on the heating and cooling energy consumption in multifamily residential buildings. This paper compares the energy performance of three HVAC systems: a direct expansion (DX) split system, a split air source heat pump (ASHP) system, and a closed-loop water source heat pump (WSHP) system with a boiler and an evaporative fluid cooler as the central heating and cooling source. All three systems use gas furnace for heating or heating backup. The comparison is made in a number of scenarios including different climate conditions, system operation schemes and applicable building codes. It is found that with the minimum code-compliant equipment efficiency, ASHP performs the best among all scenarios except in extremely code climates. WSHP tends to perform better than the split DX system in cold climates but worse in hot climates.

  19. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ROOM AIR CONDITIONING UNITS AND HUMIDIFIERS.

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE), to assist in conducting waste minimization assessments at thirty small to medium sized businesses in the state of New Jersey. One of th...

  20. ENVIRONMENTAL RESEARCH BRIEF: WASTE REDUCTION ACTIVITIES AND OPTIONS FOR A MANUFACTURER OF ROOM AIR CONDITIONING UNITS AND HUMIDIFIERS

    EPA Science Inventory

    The U.S. Environmental Protection Agency (EPA) funded a project with the New Jersey Department of Environmental Protection and Energy (NJDEPE) ,to assist in conducting waste minimization assessments at- thirty small- to medium-sized businesses in the state of New Jersey. ne of th...

  1. Retrofitting Inefficient Rooftop Air-Conditioning Units Reduces U.S. Navy Energy Use (Fact Sheet)

    SciTech Connect

    Not Available

    2014-04-01

    As part of the U.S. Navy's overall energy strategy, the National Renewable Energy Laboratory (NREL) partnered with the Naval Facilities Engineering Command (NAVFAC) to demonstrate market-ready energy efficiency measures, renewable energy generation, and energy systems integration. One such technology - retrofitting rooftop air-conditioning units with an advanced rooftop control system - was identified as a promising source for reducing energy use and costs, and can contribute to increasing energy security.

  2. The feasibility study of the waste heat air-conditioning system for automobile

    NASA Astrophysics Data System (ADS)

    Lin, Gui-Ping; Yuan, Xiu-Gan; Mei, Zhi-Guang

    1994-06-01

    In this paper, the feasibility of application of a solid-absorption system using ammonia and chlorides as working pair to automobile air-conditioning system is investigated. This system has the advantages of minimum environmental problem and utilizing waste heat from the automobile engine as thermal energy input. Analyses show that the main problem associated with the application of solid-absorption system is the size of the reactors. Techniques to solve this problem are discussed.

  3. Industry sector analysis, Hong Kong: Air conditioning equipment. Export trade information

    SciTech Connect

    Not Available

    1993-01-01

    The market survey covers the air conditioning equipment market in Hong Kong. The analysis contains statistical and narrative information on projected market demand, end-users; receptivity of Hong Kong consumers to U.S. products; the competitive situation, and market access (tariffs, non-tariff barriers, standards, taxes, distribution channels). It also contains key contact information and information on upcoming trade events related to the industry.

  4. Application information on typical hygrometers used in heating, ventilating and air conditioning (HVAC) systems

    SciTech Connect

    Kao, J.Y.; Snyder, W.J.

    1982-01-01

    Hygrometer selection information is provided for application in heating, ventilating and air-conditioning (HVAC) systems. A general review of hygrometer literature has been provided and the most commonly used ones for HVAC are discussed. Typical hygrometer parameters are listed to indicate the type of performance that can be expected. Laboratory test results of self-regulating, salt-phase transition hygrometers are presented and discussed in detail.

  5. Potential emission savings from refrigeration and air conditioning systems by using low GWP refrigerants

    DOE PAGESBeta

    Beshr, Mohamed; Aute, Vikrant; Abdelaziz, Omar; Fricke, Brian; Radermacher, Reinhard

    2016-08-24

    Refrigeration and air conditioning systems have high, negative environmental impacts due to refrigerant charge leaks from the system and their corresponding high global warming potential. Thus, many efforts are in progress to obtain suitable low GWP alternative refrigerants and more environmentally friendly systems for the future. In addition, the system’s life cycle climate performance (LCCP) is a widespread metric proposed for the evaluation of the system’s environmental impact.

  6. Validation of the criteria for initiating the cleaning of heating, ventilation, and air-conditioning (HVAC) ductwork under real conditions.

    PubMed

    Lavoie, Jacques; Marchand, Geneviève; Cloutier, Yves; Lavoué, Jérôme

    2011-08-01

    Dust accumulation in the components of heating, ventilation, and air-conditioning (HVAC) systems is a potential source of contaminants. To date, very little information is available on recognized methods for assessing dust buildup in these systems. The few existing methods are either objective in nature, involving numerical values, or subjective in nature, based on experts' judgments. An earlier project aimed at assessing different methods of sampling dust in ducts was carried out in the laboratories of the Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). This laboratory study showed that all the sampling methods were practicable, provided that a specific surface-dust cleaning initiation criterion was used for each method. However, these conclusions were reached on the basis of ideal conditions in a laboratory using a reference dust. The objective of this present study was to validate these laboratory results in the field. To this end, the laboratory sampling templates were replicated in real ducts and the three sampling methods (the IRSST method, the method of the U.S. organization National Air Duct Cleaner Association [NADCA] and that of the French organization Association pour la Prévention et l'Étude de la Contamination [ASPEC]) were used simultaneously in a statistically representative number of systems. The air return and supply ducts were also compared. Cleaning initiation criteria under real conditions were found to be 6.0 mg/100 cm(2) using the IRSST method, 2.0 mg/100 cm(2) using the NADCA method, and 23 mg/100 cm(2) using the ASPEC method. In the laboratory study, the criteria using the same methods were 6.0 for the IRSST method, 2.0 for the NADCA method, and 3.0 for the ASPEC method. The laboratory criteria for the IRSST and NADCA methods were therefore validated in the field. The ASPEC criterion was the only one to change. The ASPEC method therefore allows for the most accurate evaluation of dust accumulation in HVAC

  7. The Maintenance of Heating, Ventilating and Air-Conditioning Systems and Indoor Air Quality in Schools: A Guide for School Facility Managers. Technical Bulletin.

    ERIC Educational Resources Information Center

    Wheeler, Arthur E.

    To help maintain good indoor air quality (IAQ) in schools, guidance for the development and implementation of an effective program for maintenance and operation of heating, ventilating, and air-conditioning (HVAC) systems are discussed. Frequently, a building's occupants will complain about IAQ when the temperature or humidity are at uncomfortable…

  8. Consistent pattern of elevated symptoms in air-conditioned office buildings: a reanalysis of epidemiologic studies.

    PubMed Central

    Mendell, M J; Smith, A H

    1990-01-01

    Published studies of the relation between type of building ventilation system and work-related symptom prevalence in office workers have been contradictory. A reanalysis was performed of six studies meeting specific eligibility criteria, combining published data with unpublished information obtained from study authors. Five eligible studies were from the United Kingdom, and one was from Denmark. Standardized categories of building ventilation type were created to allow comparison of effects across studies. Within each study, prevalence odds ratios (PORs) were calculated for symptoms in each ventilation category relative to a baseline category of naturally ventilated buildings. Air-conditioned buildings were consistently associated with increased prevalence of work-related headache (POR = 1.3-3.1), lethargy (POR = 1.4-5.1), and upper respiratory/mucus membrane symptoms (POR = 1.3-4.8). Humidification was not a necessary factor for the higher symptom prevalence associated with air-conditioning. Mechanical ventilation without air-conditioning was not associated with higher symptom prevalence. The consistent associations found between type of building ventilation and reported symptom prevalence have potentially important public health and economic implications. PMID:2400029

  9. Tourists’ attitudes towards ban on smoking in air-conditioned hotel lobbies in Thailand

    PubMed Central

    Viriyachaiyo, V; Lim, A

    2009-01-01

    Background: Thailand is internationally renowned for its stringent tobacco control measures. In Thailand, a regulation banning smoking in air-conditioned hotel lobbies was issued in late 2006, causing substantial apprehension within the hospitality industry. A survey of tourists’ attitudes toward the ban was conducted. Methods: A cross-sectional survey of 5550 travellers staying in various hotels in Bangkok, Surat Thani, Phuket, Krabi and Songkhla provinces, October 2005 to December 2006. Travellers aged 15 years or older with a check-in duration of at least one day and willing to complete the questionnaire were requested by hotel staff to fill in the 5-minute questionnaire at check-in or later at their convenience. Results: Secondhand cigarette smoke was recognised as harmful to health by 89.7% of respondents. 47.8% of travellers were aware of the Thai regulation banning smoking in air-conditioned restaurants. 80.9% of the respondents agreed with the ban, particularly female non-smokers. 38.6% of survey respondents indicated that they would be more likely to visit Thailand again because of the regulation, 53.4% that the regulation would not affect their decision and 7.9% that they would be less likely to visit Thailand again. Conclusion: Banning smoking in air-conditioned hotel lobbies in Thailand is widely supported by tourists. Enforcement of the regulation is more likely to attract tourists than dissuade them from holidaying in Thailand. PMID:19364754

  10. Towards energy efficient operation of Heating, Ventilation and Air Conditioning systems via advanced supervisory control design

    NASA Astrophysics Data System (ADS)

    Oswiecinska, A.; Hibbs, J.; Zajic, I.; Burnham, K. J.

    2015-11-01

    This paper presents conceptual control solution for reliable and energy efficient operation of heating, ventilation and air conditioning (HVAC) systems used in large volume building applications, e.g. warehouse facilities or exhibition centres. Advanced two-level scalable control solution, designed to extend capabilities of the existing low-level control strategies via remote internet connection, is presented. The high-level, supervisory controller is based on Model Predictive Control (MPC) architecture, which is the state-of-the-art for indoor climate control systems. The innovative approach benefits from using passive heating and cooling control strategies for reducing the HVAC system operational costs, while ensuring that required environmental conditions are met.

  11. Air release measurements of V-oil 1404 downstream of a micro orifice at choked flow conditions

    NASA Astrophysics Data System (ADS)

    Freudigmann, H.-A.; Iben, U.; Pelz, P. F.

    2015-12-01

    This study presents measurements on air release of V-oil 1404 in the back flow of a micro orifice at choked flow conditions using a shadowgraph imaging method. The released air was determined at three positions downstream of the orifice for different pressure conditions. It was found that more than 23% of the initially dissolved air is released and appears downstream of the orifice in the form of bubbles.

  12. Thermodynamic model of a thermal storage air conditioning system with dynamic behavior

    SciTech Connect

    Fleming, E; Wen, SY; Shi, L; da Silva, AK

    2013-12-01

    A thermodynamic model was developed to predict transient behavior of a thermal storage system, using phase change materials (PCMs), for a novel electric vehicle climate conditioning application. The main objectives of the paper are to consider the system's dynamic behavior, such as a dynamic air flow rate into the vehicle's cabin, and to characterize the transient heat transfer process between the thermal storage unit and the vehicle's cabin, while still maintaining accurate solution to the complex phase change heat transfer. The system studied consists of a heat transfer fluid circulating between either of the on-board hot and cold thermal storage units, which we refer to as thermal batteries, and a liquid-air heat exchanger that provides heat exchange with the incoming air to the vehicle cabin. Each thermal battery is a shell-and-tube configuration where a heat transfer fluid flows through parallel tubes, which are surrounded by PCM within a larger shell. The system model incorporates computationally inexpensive semianalytic solution to the conjugated laminar forced convection and phase change problem within the battery and accounts for airside heat exchange using the Number of Transfer Units (NTUs) method for the liquid-air heat exchanger. Using this approach, we are able to obtain an accurate solution to the complex heat transfer problem within the battery while also incorporating the impact of the airside heat transfer on the overall system performance. The implemented model was benchmarked against a numerical study for a melting process and against full system experimental data for solidification using paraffin wax as the PCM. Through modeling, we demonstrate the importance of capturing the airside heat exchange impact on system performance, and we investigate system response to dynamic operating conditions, e.g., air recirculation. (C) 2013 Elsevier Ltd. All rights reserved.

  13. Heating, ventilating, and air conditioning deactivation thermal analysis of PUREX Plant

    SciTech Connect

    Chen, W.W.; Gregonis, R.A.

    1997-08-01

    Thermal analysis was performed for the proposed Plutonium Uranium Extraction Plant exhaust system after deactivation. The purpose of the analysis was to determine if enough condensation will occur to plug or damage the filtration components. A heat transfer and fluid flow analysis was performed to evaluate the thermal characteristics of the underground duct system, the deep-bed glass fiber filter No. 2, and the high-efficiency particulate air filters in the fourth filter building. The analysis is based on extreme variations of air temperature, relative humidity, and dew point temperature using 15 years of Hanford Site weather data as a basis. The results will be used to evaluate the need for the electric heaters proposed for the canyon exhaust to prevent condensation. Results of the analysis indicate that a condition may exist in the underground ductwork where the duct temperature can lead or lag changes in the ambient air temperature. This condition may contribute to condensation on the inside surfaces of the underground exhaust duct. A worst case conservative analysis was performed assuming that all of the water is removed from the moist air over the inside surface of the concrete duct area in the fully developed turbulent boundary layer while the moist air in the free stream will not condense. The total moisture accumulated in 24 hours is negligible. Water puddling would not be expected. The results of the analyses agree with plant operating experiences. The filters were designed to resist high humidity and direct wetting, filter plugging caused by slight condensation in the upstream duct is not a concern. 19 refs., 2 figs.

  14. Air Cleaning Technologies

    PubMed Central

    2005-01-01

    , and personal protection methods. Engineering methods that are usually carried out by the building’s heating, ventilation, and air conditioning (HVAC) system function to prevent the spread of airborne infectious pathogens by diluting (dilution ventilation) and removing (exhaust ventilation) contaminated air from a room, controlling the direction of airflow and the air flow patterns in a building. However, general wear and tear over time may compromise the HVAC system’s effectiveness to maintain adequate indoor air quality. Likewise, economic issues may curtail the completion of necessary renovations to increase its effectiveness. Therefore, when exposure to airborne infectious pathogens is a risk, the use of an in-room air cleaner to reduce the concentration of airborne pathogens and prevent the spread of airborne infectious diseases has been proposed as an alternative to renovating a HVAC system. Airborne transmission is the spread of infectious pathogens over large distances through the air. Infectious pathogens, which may include fungi, bacteria, and viruses, vary in size and can be dispersed into the air in drops of moisture after coughing or sneezing. Small drops of moisture carrying infectious pathogens are called droplet nuclei. Droplet nuclei are about 1 to 5μm in diameter. This small size in part allows them to remain suspended in the air for several hours and be carried by air currents over considerable distances. Large drops of moisture carrying infectious pathogens are called droplets. Droplets being larger than droplet nuclei, travel shorter distances (about 1 metre) before rapidly falling out of the air to the ground. Because droplet nuclei remain airborne for longer periods than do droplets, they are more amenable to engineering infection control methods than are droplets. Droplet nuclei are responsible for the airborne transmission of infectious diseases such as tuberculosis, chicken pox (varicella), measles (rubeola), and dessiminated herpes

  15. Transport of airborne particles within a room.

    PubMed

    Richmond-Bryant, J; Eisner, A D; Brixey, L A; Wiener, R W

    2006-02-01

    The objective of this study is to test a technique used to analyze contaminant transport in the wake of a bluff body under controlled experimental conditions for application to aerosol transport in a complex furnished room. Specifically, the hypothesis tested by our work is that the dispersion of contaminants in a room is related to the turbulence kinetic energy and length scale. This turbulence is, in turn, determined by the size and shape of furnishings within the room and by the ventilation characteristics. This approach was tested for indoor dispersion through computational fluid dynamics simulations and laboratory experiments. In each, 3 mum aerosols were released in a furnished room with varied contaminant release locations (at the inlet vent or under a desk). The realizable k approximately epsilon model was employed in the simulations, followed by a Lagrangian particle trajectory simulation used as input for an in-house FORTRAN code to compute aerosol concentration. For the experiments, concentrations were measured simultaneously at seven locations by laser photometry, and air velocity was measured using laser Doppler velocimetry. The results suggest that turbulent diffusion is a significant factor in contaminant residence time in a furnished room. This procedure was then expanded to develop a simplified correlation between contaminant residence time and the number of enclosing surfaces around a point containing the contaminant. Practical Implications The work presented here provides a methodology for relating local aerosol residence time to properties of room ventilation and furniture arrangement. This technique may be used to assess probable locations of high concentration by knowing only the particle release location, furniture configuration, inlet and outlet locations, and air speeds, which are all observable features. Applications of this method include development of 'rules of thumb' for first responders entering a room where an agent has been released

  16. A database and tool for boundary conditions for regional air quality modeling: description and evaluation

    NASA Astrophysics Data System (ADS)

    Henderson, B. H.; Akhtar, F.; Pye, H. O. T.; Napelenok, S. L.; Hutzell, W. T.

    2014-02-01

    Transported air pollutants receive increasing attention as regulations tighten and global concentrations increase. The need to represent international transport in regional air quality assessments requires improved representation of boundary concentrations. Currently available observations are too sparse vertically to provide boundary information, particularly for ozone precursors, but global simulations can be used to generate spatially and temporally varying lateral boundary conditions (LBC). This study presents a public database of global simulations designed and evaluated for use as LBC for air quality models (AQMs). The database covers the contiguous United States (CONUS) for the years 2001-2010 and contains hourly varying concentrations of ozone, aerosols, and their precursors. The database is complemented by a tool for configuring the global results as inputs to regional scale models (e.g., Community Multiscale Air Quality or Comprehensive Air quality Model with extensions). This study also presents an example application based on the CONUS domain, which is evaluated against satellite retrieved ozone and carbon monoxide vertical profiles. The results show performance is largely within uncertainty estimates for ozone from the Ozone Monitoring Instrument and carbon monoxide from the Measurements Of Pollution In The Troposphere (MOPITT), but there were some notable biases compared with Tropospheric Emission Spectrometer (TES) ozone. Compared with TES, our ozone predictions are high-biased in the upper troposphere, particularly in the south during January. This publication documents the global simulation database, the tool for conversion to LBC, and the evaluation of concentrations on the boundaries. This documentation is intended to support applications that require representation of long-range transport of air pollutants.

  17. Air- ice-snow interaction in the Northern Hemisphere under different stability conditions

    NASA Astrophysics Data System (ADS)

    Repina, Irina; Chechin, Dmitry; Artamonov, Arseny

    2013-04-01

    The traditional parameterizations of the atmospheric boundary layer are based on similarity theory and the coefficients of turbulent transfer, describing the atmospheric-surface interaction and the diffusion of impurities in the operational models of air pollution, weather forecasting and climate change. Major drawbacks of these parameterizations is that they are not applicable for the extreme conditions of stratification and currents over complex surfaces (such as sea ice, marginal ice zone or stormy sea). These problem could not be overcome within the framework of classical theory, i.e, by rectifying similarity functions or through the introduction of amendments to the traditional turbulent closure schemes. Lack of knowledge on the structure of the surface air layer and the exchange of momentum, heat and moisture between the rippling water surface and the atmosphere at different atmospheric stratifications is at present the major obstacle which impede proper functioning of the operational global and regional weather prediction models and expert models of climate and climate change. This is especially important for the polar regions, where in winter time the development of strong stable boundary layer in the presence of polynyas and leads usually occur. Experimental studies of atmosphere-ice-snow interaction under different stability conditions are presented. Strong stable and unstable conditions are discussed. Parametrizations of turbulent heat and gas exchange at the atmosphere ocean interface are developed. The dependence of the exchange coefficients and aerodynamic roughness on the atmospheric stratification over the snow and ice surface is experimentally confirmed. The drag coefficient is reduced with increasing stability. The behavior of the roughness parameter is simple. This result was obtained in the Arctic from the measurements over hummocked surface. The value of the roughness in the Arctic is much less than that observed over the snow in the middle and

  18. Performance of R-410A Alternative Refrigerants in a Reciprocating Compressor Designed for Air Conditioning Applications

    SciTech Connect

    Shrestha, Som S; Vineyard, Edward Allan; Mumpower, Kevin

    2016-01-01

    In response to environmental concerns raised by the use of refrigerants with high Global Warming Potential (GWP), the Air-Conditioning, Heating, and Refrigeration Institute (AHRI) has launched an industry-wide cooperative research program, referred to as the Low-GWP Alternative Refrigerants Evaluation Program (AREP), to identify and evaluate promising alternative refrigerants for major product categories. After successfully completing the first phase of the program in December 2013, AHRI launched a second phase of the Low-GWP AREP in 2014 to continue research in areas that were not previously addressed, including refrigerants in high ambient conditions, refrigerants in applications not tested in the first phase, and new refrigerants identified since testing for the program began. Although the Ozone Depletion Potential of R-410A is zero, this refrigerant is under scrutiny due to its high GWP. Several candidate alternative refrigerants have already demonstrated low global warming potential. Performance of these low-GWP alternative refrigerants is being evaluated for Air conditioning and heat pump applications to ensure acceptable system capacity and efficiency. This paper reports the results of a series of compressor calorimeter tests conducted for the second phase of the AREP to evaluate the performance of R-410A alternative refrigerants in a reciprocating compressor designed for air conditioning systems. It compares performance of alternative refrigerants ARM-71A, L41-1, DR-5A, D2Y-60, and R-32 to that of R-410A over a wide range of operating conditions. The tests showed that, in general, cooling capacities were slightly lower (except for the R-32), but energy efficiency ratios (EER) of the alternative refrigerants were comparable to that of R-410A.

  19. Numerical modeling of cold room's hinged door opening and closing processes

    NASA Astrophysics Data System (ADS)

    Carneiro, R.; Gaspar, P. D.; Silva, P. D.; Domingues, L. C.

    2016-06-01

    The need of rationalize energy consumption in agrifood industry has fasten the development of methodologies to improve the thermal and energy performances of cold rooms. This paper presents a three-dimensional (3D) transient Computational Fluid Dynamics (CFD) modelling of a cold room to evaluate the air infiltration rate through hinged doors. A species transport model is used for modelling the tracer gas concentration decay technique. Numerical predictions indicate that air temperature difference between spaces affects the air infiltration. For this case study, the infiltration rate increases 0.016 m3 s-1 per K of air temperature difference. The knowledge about the evolution of air infiltration during door opening/closing times allows to draw some conclusions about its influence on the air conditions inside the cold room, as well as to suggest best practices and simple technical improvements that can minimize air infiltration, and consequently improve thermal performance and energy consumption rationalization.

  20. Study on an Efficient Dehumidifying Air-conditioning System utilizing Phase Change of Intermediate Pressure Refrigerant

    NASA Astrophysics Data System (ADS)

    Maeda, Kensaku; Inaba, Hideo

    The present study has proven a new dehumidifying system that aimed to reduce the sensible heat factor(SHF) of cooling process without using additional heat to relieve the internationally indicated conflict between energy saving and dehumidification necessary for keeping adequate indoor air quality (IAQ). In this system, we used intermediate pressure refrigerant in a vapor compression refrigerating cycle as heat transfer medium of a characteristic heat exchanger to precool the process air entering into an evaporator as well as to reheat the process air leaving from the evaporator. By this system, the present results achieved higher moisture removal and consequently higher efficiency of dehumidifying process. In addition to this fact, since this system has capability of integration into air-conditioning apparatus(HVAC system), it will be able to work for wide range of cooling load by variable SHF function. In the present paper, technical information, experimental results, and simulation results which assumed to apply this system into HVAC system are reported.

  1. TECNAIRE winter field campaign: turbulent characteristics and their influence on air quality conditions

    NASA Astrophysics Data System (ADS)

    Yagüe, Carlos; Román Cascón, Carlos; Maqueda, Gregorio; Sastre, Mariano; Arrillaga, Jon A.; Artíñano, Begoña; Diaz-Ramiro, Elías; Gómez-Moreno, Francisco J.; Borge, Rafael; Narros, Adolfo; Pérez, Javier

    2016-04-01

    An urban field campaign was conducted at an air pollution hot spot in Madrid city (Spain) during winter 2015 (from 16th February to 2nd March). The zone selected for the study is a square (Plaza Fernández Ladreda) located in the southern part of the city. This area is an important intersection of several principal routes, and therefore a significant impact in the air quality of the area is found due to the high traffic density. Meteorological data (wind speed and direction, air temperature, relative humidity, pressure, precipitation and global solar radiation) were daily recorded as well as micrometeorological measurements obtained from two sonic anemometers. To characterize this urban atmospheric boundary layer (uABL), micrometeorological parameters (turbulent kinetic energy -TKE-, friction velocity -u∗- and sensible heat flux -H-) are calculated, considering 5-minute average for variance and covariance evaluations. Furthermore, synoptic atmospheric features were analyzed. As a whole, a predominant influence of high pressure systems was found over the Atlantic Ocean and western Spain, affecting Madrid, but during a couple of days (17th and 21st February) some atmospheric instability played a role. The influence of the synoptic situation and specially the evolution of the micrometeorological conditions along the day on air quality characteristics (Particulate Matter concentrations: PM10, PM2.5 and PM1, and NOx concentrations) are analyzed and shown in detail. This work has been financed by Madrid Regional Research Plan through TECNAIRE (P2013/MAE-2972).

  2. Air-dried cells from the anhydrobiotic insect, Polypedilum vanderplanki, can survive long term preservation at room temperature and retain proliferation potential after rehydration.

    PubMed

    Watanabe, Kazuyo; Imanishi, Shigeo; Akiduki, Gaku; Cornette, Richard; Okuda, Takashi

    2016-08-01

    Pv11, a cell line derived from the anhydrobiotic insect, Polypedilum vanderplanki, was preserved in a dry form (only 6% residual moisture) at room temperature for up to 251 days and restarted proliferating after rehydration. A previous study already reported survival of Pv11 cells after desiccation, but without subsequent proliferation. Here, the protocol was improved to increase survival and achieve proliferation of Pv11 cells after dry storage. The method basically included preincubation, desiccation and rehydration processes and each step was investigated. So far, preincubation in a 600 mM trehalose solution for 48 h before dehydration was the most favourable preconditioning to achieve successful dry preservation of Pv11 cells, allowing about 16% of survival after rehydration and subsequent cell proliferation. Although the simple air-dry method established for Pv11 cells here was not applicable for successful dry-preservation of other insect cell lines, Pv11 is the first dry-preservable animal cell line and will surely contribute not only to basic but also applied sciences. PMID:27207249

  3. Growth condition dependence of photoluminescence polarization in (100) GaAs/AlGaAs quantum wells at room temperature

    SciTech Connect

    Iba, Satoshi; Saito, Hidekazu; Yuasa, Shinji; Watanabe, Ken; Ohno, Yuzo

    2015-08-28

    We conducted systematic measurements on the carrier lifetime (τ{sub c}), spin relaxation time (τ{sub s}), and circular polarization of photoluminescence (P{sub circ}) in (100) GaAs/AlGaAs multiple quantum wells grown by molecular beam epitaxy (MBE). The τ{sub c} values are strongly affected by MBE growth conditions (0.4–9 ns), whereas the τ{sub s} are almost constant at about 0.13 ns. The result suggests that spin detection efficiency [τ{sub s}/(τ{sub c} + τ{sub s})], which is expected to be proportional to a steady-state P{sub circ}, is largely dependent on growth condition. We confirmed that the P{sub circ} has similar dependence on growth condition to those of τ{sub s}/(τ{sub c} + τ{sub s}) values. The study thus indicates that choosing the appropriate growth condition of the QW is indispensable for obtaining a high P{sub circ} from a spin-polarized light-emitting diode (spin-LED)

  4. Automated Air Traffic Control Operations with Weather and Time-Constraints: A First Look at (Simulated) Far-Term Control Room Operations

    NASA Technical Reports Server (NTRS)

    Prevot, Thomas; Homola, Jeffrey R.; Martin, Lynne H.; Mercer, Joey S.; Cabrall, Christopher C.

    2011-01-01

    In this paper we discuss results from a recent high fidelity simulation of air traffic control operations with automated separation assurance in the presence of weather and time-constraints. We report findings from a human-in-the-loop study conducted in the Airspace Operations Laboratory (AOL) at the NASA Ames Research Center. During four afternoons in early 2010, fifteen active and recently retired air traffic controllers and supervisors controlled high levels of traffic in a highly automated environment during three-hour long scenarios, For each scenario, twelve air traffic controllers operated eight sector positions in two air traffic control areas and were supervised by three front line managers, Controllers worked one-hour shifts, were relieved by other controllers, took a 3D-minute break, and worked another one-hour shift. On average, twice today's traffic density was simulated with more than 2200 aircraft per traffic scenario. The scenarios were designed to create peaks and valleys in traffic density, growing and decaying convective weather areas, and expose controllers to heavy and light metering conditions. This design enabled an initial look at a broad spectrum of workload, challenge, boredom, and fatigue in an otherwise uncharted territory of future operations. In this paper we report human/system integration aspects, safety and efficiency results as well as airspace throughput, workload, and operational acceptability. We conclude that, with further refinements. air traffic control operations with ground-based automated separation assurance can be an effective and acceptable means to routinely provide very high traffic throughput in the en route airspace.

  5. Respiratory viral infections and effects of meteorological parameters and air pollution in adults with respiratory symptoms admitted to the emergency room

    PubMed Central

    Silva, Denise R; Viana, Vinícius P; Müller, Alice M; Livi, Fernando P; Dalcin, Paulo de Tarso R

    2014-01-01

    Background Respiratory viral infections (RVIs) are the most common causes of respiratory infections. The prevalence of respiratory viruses in adults is underestimated. Meteorological variations and air pollution are likely to play a role in these infections. Objectives The objectives of this study were to determine the number of emergency visits for influenza-like illness (ILI) and severe acute respiratory infection (SARI) and to evaluate the association between ILI/SARI, RVI prevalence, and meteorological factors/air pollution, in the city of Porto Alegre, Brazil, from November 2008 to October 2010. Methods Eleven thousand nine hundred and fifty-three hospitalizations (adults and children) for respiratory symptoms were correlated with meteorological parameters and air pollutants. In a subset of adults, nasopharyngeal aspirates were collected and analyzed through IFI test. The data were analyzed using time-series analysis. Results Influenza-like illness and SARI were diagnosed in 3698 (30·9%) and 2063 (17·7%) patients, respectively. Thirty-seven (9·0%) samples were positive by IFI and 93 of 410 (22·7%) were IFI and/or PCR positive. In a multivariate logistic regression model, IFI positivity was statistically associated with absolute humidity, use of air conditioning, and presence of mold in home. Sunshine duration was significantly associated with the frequency of ILI cases. For SARI cases, the variables mean temperature, sunshine duration, relative humidity, and mean concentration of pollutants were singnificant. Conclusions At least 22% of infections in adult patients admitted to ER with respiratory complaints were caused by RVI. The correlations among meteorological variables, air pollution, ILI/SARI cases, and respiratory viruses demonstrated the relevance of climate factors as significant underlying contributors to the prevalence of RVI. PMID:24034701

  6. Ground-water conditions at Beale Air Force Base and vicinity, California

    USGS Publications Warehouse

    Page, R.W.

    1980-01-01

    Ground-water conditions were studied in a 168-square-mile area between the Sierra Nevada and the Feather River in Yuba County, Calif. The area is in the eastern part of the Sacramento Valley and includes most of Beale Air Force Base. Source, occurrence, movement, and chemical quality of the ground water were evaluated. Ground water occurs in sedimentary and volcanic rocks of Tertiary and Quaternary age. The base of the freshwater is in the undifferentiated sedimentary rocks of Oligocene and Eocene age, that contain water of high dissolved-solids concentration. The ground water occurs under unconfined and partly confined conditions. At Beale Air Force Base it is at times partly confined. Recharge is principally from the rivers. Pumpage in the study area was estimated to be 129,000 acre-feet in 1975. In the 1960's, water levels in most parts of the study area declined less rapidly than in earlier years or became fairly stable. In the 1970's, water levels at Beale Air Force Base declined only slightly. Spacing of wells on the base and rates of pumping are such that excessive pumping interference is avoided. Water quality at the base and throughout the study area is generally good. Dissolved-solids concentrations are 700 to 900 milligrams per liter in the undifferentiated sedimentary rocks beneath the base well field. (USGS)

  7. Experimental performance study of a proposed desiccant based air conditioning system.

    PubMed

    Bassuoni, M M

    2014-01-01

    An experimental investigation on the performance of a proposed hybrid desiccant based air conditioning system referred as HDBAC is introduced in this paper. HDBAC is mainly consisted of a liquid desiccant dehumidification unit integrated with a vapor compression system (VCS). The VCS unit has a cooling capacity of 5.27 kW and uses 134a as refrigerant. Calcium chloride (CaCl2) solution is used as the working desiccant material. HDBAC system is used to serve low sensible heat factor applications. The effect of different parameters such as, process air flow rate, desiccant solution flow rate, evaporator box and condenser box solution temperatures, strong solution concentration and regeneration temperature on the performance of the system is studied. The performance of the system is evaluated using some parameters such as: the coefficient of performance (COPa), specific moisture removal and energy saving percentage. A remarkable increase of about 54% in the coefficient of performance of the proposed system over VCS with reheat is achieved. A maximum overall energy saving of about 46% is observed which emphasizes the use of the proposed system as an energy efficient air conditioning system. PMID:25685475

  8. Experimental performance study of a proposed desiccant based air conditioning system

    PubMed Central

    Bassuoni, M.M.

    2013-01-01

    An experimental investigation on the performance of a proposed hybrid desiccant based air conditioning system referred as HDBAC is introduced in this paper. HDBAC is mainly consisted of a liquid desiccant dehumidification unit integrated with a vapor compression system (VCS). The VCS unit has a cooling capacity of 5.27 kW and uses 134a as refrigerant. Calcium chloride (CaCl2) solution is used as the working desiccant material. HDBAC system is used to serve low sensible heat factor applications. The effect of different parameters such as, process air flow rate, desiccant solution flow rate, evaporator box and condenser box solution temperatures, strong solution concentration and regeneration temperature on the performance of the system is studied. The performance of the system is evaluated using some parameters such as: the coefficient of performance (COPa), specific moisture removal and energy saving percentage. A remarkable increase of about 54% in the coefficient of performance of the proposed system over VCS with reheat is achieved. A maximum overall energy saving of about 46% is observed which emphasizes the use of the proposed system as an energy efficient air conditioning system. PMID:25685475

  9. Enhancement of NK Cell Cytotoxicity Induced by Long-Term Living in Negatively Charged-Particle Dominant Indoor Air-Conditions

    PubMed Central

    Nishimura, Yasumitsu; Takahashi, Kazuaki; Mase, Akinori; Kotani, Muneo; Ami, Kazuhisa; Maeda, Megumi; Shirahama, Takashi; Lee, Suni; Matsuzaki, Hidenori; Kumagai-Takei, Naoko; Yoshitome, Kei; Otsuki, Takemi

    2015-01-01

    Investigation of house conditions that promote health revealed that negatively charged-particle dominant indoor air-conditions (NCPDIAC) induced immune stimulation. Negatively charged air-conditions were established using a fine charcoal powder on walls and ceilings and utilizing forced negatively charged particles (approximate diameter: 20 nm) dominant in indoor air-conditions created by applying an electric voltage (72 V) between the backside of the walls and the ground. We reported previously that these conditions induced a slight and significant increase of interleukin-2 during a 2.5-h stay and an increase of NK cell cytotoxicity when examining human subjects after a two-week night stay under these conditions. In the present study, seven healthy volunteers had a device installed to create NCPDIAC in the living or sleeping rooms of their own homes. Every three months the volunteers then turned the NCPDIAC device on or off. A total of 16 ON and 13 OFF trials were conducted and their biological effects were analyzed. NK activity increased during ON trials and decreased during OFF trials, although no other adverse effects were found. In addition, there were slight increases of epidermal growth factor (EGF) during ON trials. Furthermore, a comparison of the cytokine status between ON and OFF trials showed that basic immune status was stimulated slightly during ON trials under NCPIADC. Our overall findings indicate that the NCPDIAC device caused activation of NK activity and stimulated immune status, particularly only on NK activity, and therefore could be set in the home or office buildings. PMID:26173062

  10. An Analysis of Price Determination and Markups in the Air-Conditioning and Heating Equipment Industry

    SciTech Connect

    Dale, Larry; Millstein, Dev; Coughlin, Katie; Van Buskirk, Robert; Rosenquist, Gregory; Lekov, Alex; Bhuyan, Sanjib

    2004-01-30

    In this report we calculate the change in final consumer prices due to minimum efficiency standards, focusing on a standard economic model of the air-conditioning and heating equipment (ACHE) wholesale industry. The model examines the relationship between the marginal cost to distribute and sell equipment and the final consumer price in this industry. The model predicts that the impact of a standard on the final consumer price is conditioned by its impact on marginal distribution costs. For example, if a standard raises the marginal cost to distribute and sell equipment a small amount, the model predicts that the standard will raise the final consumer price a small amount as well. Statistical analysis suggest that standards do not increase the amount of labor needed to distribute equipment the same employees needed to sell lower efficiency equipment can sell high efficiency equipment. Labor is a large component of the total marginal cost to distribute and sell air-conditioning and heating equipment. We infer from this that standards have a relatively small impact on ACHE marginal distribution and sale costs. Thus, our model predicts that a standard will have a relatively small impact on final ACHE consumer prices. Our statistical analysis of U.S. Census Bureau wholesale revenue tends to confirm this model prediction. Generalizing, we find that the ratio of manufacturer price to final consumer price prior to a standard tends to exceed the ratio of the change in manufacturer price to the change in final consumer price resulting from a standard. The appendix expands our analysis through a typical distribution chain for commercial and residential air-conditioning and heating equipment.

  11. LiCl dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    SciTech Connect

    Ko, S.M.

    1980-06-03

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system. 4 figs.

  12. Analysis of bidirectional PWM converter for application of residential solar air conditioning system

    SciTech Connect

    Kim, H.S.; Choe, G.H.; Yu, G.J.; Song, J.S.

    1994-12-31

    In the conventional solar air conditioning system the diode rectifier is used to build up DC link voltage from ac utility source. The diode rectifier is simple and cheap but the reverse of power flow cannot be made. It can derate the utilization of solar cell and also there have occurred the problems of low power factor and plentiful harmonics at the ac input side. Hence in addition to peak power cutting in summer, some advantages can be obtained by adopting the PWM converter to the solar air conditioner. As a result, obtained are the characteristics of the PWM converter such as low distorted current waveform, unity power factor. Also the proposed system is verified by examining the dynamics to step load change and also power reversal testing.

  13. Cascade Reverse Osmosis Air Conditioning System: Cascade Reverse Osmosis and the Absorption Osmosis Cycle

    SciTech Connect

    2010-09-01

    BEETIT Project: Battelle is developing a new air conditioning system that uses a cascade reverse osmosis (RO)-based absorption cycle. Analyses show that this new cycle can be as much as 60% more efficient than vapor compression, which is used in 90% of air conditioners. Traditional vapor-compression systems use polluting liquids for a cooling effect. Absorption cycles use benign refrigerants such as water, which is absorbed in a salt solution and pumped as liquid—replacing compression of vapor. The refrigerant is subsequently separated from absorbing salt using heat for re-use in the cooling cycle. Battelle is replacing thermal separation of refrigerant with a more efficient reverse osmosis process. Research has shown that the cycle is possible, but further investment will be needed to reduce the number of cascade reverse osmosis stages and therefore cost.

  14. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    DOEpatents

    Ko, Suk M.

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  15. In-car particles and cardiovascular health: an air conditioning-based intervention study.

    PubMed

    Chuang, Hsiao-Chi; Lin, Lian-Yu; Hsu, Ya-Wen; Ma, Chih-Ming; Chuang, Kai-Jen

    2013-05-01

    Exposure to traffic-related particulate matter (PM) is considered a potential risk for cardiovascular events. Little is known about whether improving air quality in car can modify cardiovascular effects among human subjects during commuting. We recruited a panel of 60 healthy subjects to commute for 2 h by a car equipped with an air conditioning (AC) system during the morning rush hour in Taipei. Operation modes of AC system using outside air (OA-mode), circulating inside air (IA-mode) and turning off (Off-mode) were examined. Repeated measurements of heart rate variability (HRV) indices, PM≤2.5 μm in aerodynamic diameter (PM2.5) and noise level were conducted for each participant in different modes during the commute. We used linear mixed-effects models to associate HRV indices with in-car PM2.5. We found that decreases in HRV indices were associated with increased levels of in-car PM2.5. For Off-mode, an interquartile range (IQR) increase in in-car PM2.5 with 15-min moving average was associated with 2.7% and 4.1% decreases in standard deviation of NN intervals (SDNN) and the square root of the mean of the sum of the squares of differences between adjacent NN intervals (r-MSSD), respectively. During OA and IA modes, participants showed slight decreases in SDNN (OA mode: 0.1%; IA mode: 1.3%) and r-MSSD (OA mode: 1.1%; IA mode: 1.8%) by an IQR increase in in-car PM2.5 with 15-min moving average. We concluded that in-car PM2.5 is associated with autonomic alteration. Utilization of the car's AC system can improve air quality and modify the effects of in-car PM2.5 on HRV indices among human subjects during the commute. PMID:23523729

  16. Proposal for a Vehicle Level Test Procedure to Measure Air Conditioning Fuel Use

    SciTech Connect

    Rugh, J. P.

    2010-04-01

    The air-conditioning (A/C) compressor load significantly impacts the fuel economy of conventional vehicles and the fuel use/range of plug-in hybrid electric vehicles (PHEV). A National Renewable Energy Laboratory (NREL) vehicle performance analysis shows the operation of the air conditioner reduces the charge depletion range of a 40-mile range PHEV from 18% to 30% in a worst case hot environment. Designing for air conditioning electrical loads impacts PHEV and electric vehicle (EV) energy storage system size and cost. While automobile manufacturers have climate control procedures to assess A/C performance, and the U.S. EPA has the SCO3 drive cycle to measure indirect A/C emissions, there is no automotive industry consensus on a vehicle level A/C fuel use test procedure. With increasing attention on A/C fuel use due to increased regulatory activities and the development of PHEVs and EVs, a test procedure is needed to accurately assess the impact of climate control loads. A vehicle thermal soak period is recommended, with solar lamps that meet the SCO3 requirements or an alternative heating method such as portable electric heaters. After soaking, the vehicle is operated over repeated drive cycles or at a constant speed until steady-state cabin air temperature is attained. With this method, the cooldown and steady-state A/C fuel use are measured. This method can be run at either different ambient temperatures to provide data for the GREEN-MAC-LCCP model temperature bins or at a single representative ambient temperature. Vehicles with automatic climate systems are allowed to control as designed, while vehicles with manual climate systems are adjusted to approximate expected climate control settings. An A/C off test is also run for all drive profiles. This procedure measures approximate real-world A/C fuel use and assess the impact of thermal load reduction strategies.

  17. The Oklahoma Field Test: Air-conditioning electricity savings from standard energy conservation measures, radiant barriers, and high-efficiency window air conditioners

    SciTech Connect

    Ternes, M.P.; Levins, W.P.

    1992-08-01

    A field test Involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMS) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption models and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The following conclusions were drawn from the study: (1) programs directed at reducing air-conditioning electricity consumption should be targeted at clients with high consumption to improve cost effectiveness; (2) replacing low-efficiency air conditioners with high-efficiency units should be considered an option in a weatherization program directed at reducing air-conditioning electricity consumption; (3) ECMs currently being installed under the Oklahoma WAP (chosen based on effectiveness at reducing space-heating energy consumption) should continue to be justified based on their space-heating energy savings potential only; and (4) attic radiant barriers should not be included in the Oklahoma WAP if alternatives with verified savings are available or until further testing demonstrates energy savings or other benefits in this typo of housing.

  18. The Oklahoma Field Test: Air-Conditioning Electricity Savings from Standard Energy Conservation Measures, Radiant Barriers, and High-Efficiency Window Air Conditioners

    SciTech Connect

    Ternes, M.P.

    1992-01-01

    A field test involving 104 houses was performed in Tulsa, Oklahoma, to measure the air-conditioning electricity consumption of low-income houses equipped with window air conditioners, the reduction in this electricity consumption attributed to the installation of energy conservation measures (ECMs) as typically installed under the Oklahoma Weatherization Assistance Program (WAP), and the reduction achieved by the replacement of low-efficiency window air conditioners with high-efficiency units and the installation of attic radiant barriers. Air-conditioning electricity consumption and indoor temperature were monitored weekly during the pre-weatherization period (June to September 1988) and post-weatherization period (May to September 1989). House energy consumption models and regression analyses were used to normalize the air-conditioning electricity savings to average outdoor temperature conditions and the pre-weatherization indoor temperature of each house. The average measured pre-weatherization air-conditioning electricity consumption was 1664 kWh/year ($119/year). Ten percent of the houses used less than 250 kWh/year, while another 10% used more than 3000 kWh/year. An average reduction in air-conditioning electricity consumption of 535 kWh/year ($38/year and 28% of pre-weatherization consumption) was obtained from replacement of one low-efficiency window air conditioner (EER less than 7.0) per house with a high-efficiency unit (EER greater than 9.0). For approximately the same cost, savings tripled to 1503 kWh/year ($107/year and 41% of pre-weatherization consumption) in those houses with initial air-conditioning electricity consumption greater than 2750 kWh/year. For these houses, replacement of a low-efficiency air conditioner with a high-efficiency unit was cost effective using the incremental cost of installing a new unit now rather than later; the average installation cost for these houses under a weatherization program was estimated to be $786. The

  19. AIR TOXICS CONTROL "SITUATION ROOM"

    EPA Science Inventory

    The paper describes one component of the Environmental Protection Agency's (EPA's) efforts to assist state and local environmental agencies and its own egional offices in response to their increased responsibilities for' planning, valuating, and approving control approaches for r...

  20. Fuel-Free Compressed-Air Energy Storage: Fuel-Free, Ubiquitous Compressed-Air Energy Storage and Power Conditioning

    SciTech Connect

    2010-09-13

    GRIDS Project: General Compression has developed a transformative, near-isothermal compressed air energy storage system (GCAES) that prevents air from heating up during compression and cooling down during expansion. When integrated with renewable generation, such as a wind farm, intermittent energy can be stored in compressed air in salt caverns or pressurized tanks. When electricity is needed, the process is reversed and the compressed air is expanded to produce electricity. Unlike conventional compressed air energy storage (CAES) projects, no gas is burned to convert the stored high-pressure air back into electricity. The result of this breakthrough is an ultra-efficient, fully shapeable, 100% renewable and carbon-free power product. The GCAES™ system can provide high quality electricity and ancillary services by effectively integrating renewables onto the grid at a cost that is competitive with gas, coal and nuclear generation.