121,909 research outputs found
Designing for ventilation in cold weather apparel
No full textThe fundamental criterion for clothing comfort of cold weather garments is dictated by insulation and permeability (breathability) to maintain a warm dry skin for the active wearer. This chapter reviews water vapour and moisture transport from the skin through clothing to the environment in cold weather and its dependence on clothing thermal and evaporative resistances and layering in cold clothing designs. The chapter then describes the mechanisms and physical model of microclimate (skin-adjacent air layer) ventilation in cold weather apparel designed for active people. It emphasizes factors affecting enhanced ventilation through controllable clothing apertures, clothing physical properties, size of microclimate air layer, and human motion including frequency and swing of limbs. Finally, the chapter forwards recommendations for design of versatile-adjustable clothing for highly active people and future research trends to improve ensemble design and develop convenient tools for assessing clothing ventilation and performance. © 2009 Woodhead Publishing Limited All rights reserved.American Society for Testing and Materials, 1983, D73775 ASTM; Bouskill LM, 2002, AIHAJ, V63, P262, DOI 10.1080-15428110208984712; Fan JT, 2003, EXP THERM FLUID SCI, V27, P723, DOI 10.1016-S0894-1777(02)00305-9; Fohr JP, 2002, TEXT RES J, V72, P1, DOI 10.1177-004051750207200101; Fransson JHM, 2004, J FLUID STRUCT, V19, P1031, DOI 10.1016-j.jfluidstructs.2004.06.005; GEISBRECHT GG, 2003, WINT WILD MED C JACK; Ghaddar N, 2005, INT J HEAT MASS TRAN, V48, P3151, DOI 10.1016-j.ijheatmasstransfer.2005.03.001; Ghaddar N, 2006, THERMAL AND MOISTURE TRANSPORT IN FIBROUS MATERIALS, P271, DOI 10.1533-9781845692261.2.271; GHADDAR N, 2008, ASME IN PRESS; Ghali K, 2006, J HEAT TRANS-T ASME, V128, P908, DOI 10.1115-1.2241811; GIBSON PW, 1999, REV NUMERICAL MODELI, P117; HAVENITH G, 1990, ERGONOMICS, V33, P989, DOI 10.1080-00140139008925308; Havenith G, 1999, ANN OCCUP HYG, V43, P289, DOI 10.1016-S0003-4878(99)00051-4; Havenith G, 2004, ERGONOMICS, V47, P1424, DOI 10.1080-00140130410001704428; HAVENITH G, 2000, ENV ERGONOMICS, V10, P125; Holmer I, 1995, ANN OCCUP HYG, V39, P809, DOI 10.1016-0003-4878(95)00041-0; JAROUDI E, 2006, P 13 INT HEAT TRANSF; KEIGHLEY JH, 1985, J COATED FABRICS, V15, P89, DOI 10.1177-152808378501500203; Lotens WA, 1993, THESIS TNO I PERCEPT; McCullough EA, 1989, ASHRAE T, V95, P316; MCCULLOUGH EA, 1992, P 5 INT C ENV ERG MA, P68; RUCKMAN JE, 1997, J COATED FABRICS, V26, P293, DOI 10.1177-152808379702600405; Sobera MP, 2003, AICHE J, V49, P3018, DOI 10.1002-aic.690491204; SOBERA MP, 2006, PHYS FLUIDS, V18, P106; Wu HJ, 2008, INT J THERM SCI, V47, P641, DOI 10.1016-j.ijthennalsci.2007.04.00821
Convection and ventilation in fabric layers
No full text[No abstract available]Acheson D J, 1990, ELEMENTARY FLUID DYN; American Society for Testing and Materials, 1983, D73775 ASTM; AMIRI A, 1994, INT J HEAT MASS TRAN, V37, P939, DOI 10.1016-0017-9310(94)90219-4; Amiri A, 1998, INT J HEAT MASS TRAN, V41, P4259, DOI 10.1016-S0017-9310(98)00120-3; [Anonymous], 1997, ASHRAE HDB; DANIELSSON U, 1993, THESIS ROYAL I TECHN; Fanger PO, 1982, THERMAL COMFORT ANAL, P156; FARNWORTH B, 1986, TEXT RES J, V56, P653, DOI 10.1177-004051758605601101; FONSECA GF, 1965, TEXT RES J, V35, P95, DOI 10.1177-004051756503500201; FOURT L, 1971, CLOTHING COMFORT FUN; Ghaddar N, 2005, INT J HEAT MASS TRAN, V48, P3151, DOI 10.1016-j.ijheatmasstransfer.2005.03.001; GHADDAR N, 2005, P ASME 2005 SUMM HEA; Ghaddar N, 2005, J HEAT TRANS-T ASME, V127, P287, DOI 10.1115-1.1857949; Ghaddar N, 2003, INT J THERM SCI, V42, P605, DOI 10.1016-S1290-0729(03)00026-7; Ghali K, 2002, J HEAT TRANS-T ASME, V124, P530, DOI 10.1115-1.1471524; GHALI K, 2004, P 1 INT C THERM ENG; Ghali K, 2002, INT J HEAT MASS TRAN, V45, P3703, DOI 10.1016-S0017-9310(02)00088-1; Ghali K, 2002, J POROUS MEDIA, V5, P17; HARTER KL, 1981, TEXT RES J, V51, P345, DOI 10.1177-004051758105100506; HAVENITH G, 1990, ERGONOMICS, V33, P67, DOI 10.1080-00140139008927094; HAVENITH G, 1990, ERGONOMICS, V33, P989, DOI 10.1080-00140139008925308; HONG S, 1992, THESIS KANSAS STATE; JONES BW, 1992, ASHRAE TRAN, V98, P189; JONES BW, 1990, P INT C ENV ERG AUST, P66; JONES BW, 1985, P CLIMA 2000 WORLD C, V4, P1; Kerslake D.M., 1972, STRESS HOT ENV; Kuznetsov AV, 1998, TRANSPORT PHENOMENA IN POROUS MEDIA, P103, DOI 10.1016-B978-008042843-7-50005-2; Kuznetsov AV, 1997, INT J HEAT MASS TRAN, V40, P1001, DOI 10.1016-0017-9310(96)00179-2; KUZNETSOV AV, 1993, INT J HEAT MASS TRAN, V37, P3030; LAMOREUX LW, 1971, B PROSTHET RES, P3; Lee DY, 1999, INT J HEAT MASS TRAN, V42, P423, DOI 10.1016-S0017-9310(98)00185-9; LI Y, 1997, THESIS KANSAS STATE; Lotens W, 1988, ENV ERGONOMICS, P162; Lotens WA, 1993, THESIS TNO I PERCEPT; McCullogh E., 1985, ASHRAE T, V91, P29; McCullough EA, 1989, ASHRAE T, V95, P316; MINCOWYCZ WJ, 1999, INT J HEAT MASS TRAN, V42, P3373; Morris G. J., 1953, J TEXT I, V44, P449; Morton W.E., 1975, PHYS PROPERTIES TEXT; NIELSEN R, 1985, ERGONOMICS, V28, P1617, DOI 10.1080-00140138508963299; NISHI Y, 1970, ASHRAE T, V75, P137; REES WH, 1941, J TEXT I, V32, P149; Straatman AG, 2002, PHYS FLUIDS, V14, P1938, DOI 10.1063-1.1476673; Vafai K., 1990, ASME, V112, P690; VOKAC Z, 1973, TEXT RES J, V42, P474; Womersley J. R., 1957, ELASTIC TUBE THEORY, P56; Woodcock A.H, 1962, TEXT RES J, V32, P628, DOI 10.1177-00405175620320080246
Model-based optimal supervisory control of chilled ceiling displacement ventilation system
No full textThe aim of this paper is to develop an optimized online supervisory control predictive tool for the chilled ceiling displacement ventilation (CC-DV) system to minimize energy consumption while creating the best indoor air quality (IAQ) and thermal comfort. The online controller is designed to operate under an optimized control strategy with five control set points. A dynamic multi-variable objective cost function is formulated for the supervisory control of the CC-DV system performance indices and constraints, and is solved using genetic algorithm. The design of the optimized controller takes into consideration the response time of three-way valves, reheat, and supply fan to employ signaled changes in set points. The developed online controller response to load changes and its ability to change system set points to optimally meet unknown load and constrains are tested and evaluated under the simulated 'real life' environment for a case study. It is shown that the implemented online optimized controller is robust, and its development contributes to improved CC-DV system energy efficiency. © 2011 Elsevier B.V.ASHRAE, 2007, 6222007 ASHRAE; ASHRAE. American Society of Heating Refrigerating and Air Conditioning Engineers, 2005, HDB FUND; Ayoub M, 2006, HVACandR RES, V12, P1005, DOI 10.1080-10789669.2006.10391448; Braun J.E., 1989, ASHRAE T, V95, P164; Chow TT, 2002, ENERG BUILDINGS, V34, P103, DOI 10.1016-S0378-7788(01)00085-8; CONROY C, 2001, ASHRAE T, V107, P1; CURTISS PS, 1994, P ASME INT SOL EN C, P429; Dodier RH, 2004, J SOL ENERG-T ASME, V126, P592, DOI 10.1115-1.1637640; Fanger P.O., 1982, THERMAL COMFORT ANAL; GAMACHO E, 1999, MODEL PREDICTIVE CON; Ghaddar N., 2008, ASHRAE T, V143, P574; Ghaddar N, 2010, INT J ENERG RES, V34, P1328, DOI 10.1002-er.1677; Ghali K, 2007, INT J ENERG RES, V31, P743, DOI 10.1002-er.1266; Gouda MM, 2002, BUILD ENVIRON, V37, P1255, DOI 10.1016-S0360-1323(01)00121-4; House JM, 1995, ASHRAE TRAN, V101, P647; Jeong JW, 2004, APPL THERM ENG, V24, P2055, DOI 10.1016-j.applthermaleng.2004.01.017; Keblawi A, 2009, ENERG BUILDINGS, V41, P1155, DOI 10.1016-j.enbuild.2009.05.009; LARET L, 2000, P 7 INT C HEAT AIR C; Lau J, 2006, ENERG BUILDINGS, V38, P1212, DOI 10.1016-j.enbuild.2006.02.006; Massie Darrell D., 1998, ASHRAE T, V101, P221; Mitchell M., 1997, INTRO GENETIC ALGORI; Mossolly M, 2009, ENERGY, V34, P58, DOI 10.1016-j.energy.2008.10.001; Mossolly M, 2008, ASHRAE T, V143, P541; Nassif N, 2005, HVACandR RES, V11, P459, DOI 10.1080-10789669.2005.10391148; Niu JL, 2002, ENERG BUILDINGS, V34, P487, DOI 10.1016-S0378-7788(01)00132-3; Novoselac A, 2002, ENERG BUILDINGS, V34, P497, DOI 10.1016-S0378-7788(01)00134-7; Riffat SB, 2004, INT J ENERG RES, V28, P257, DOI 10.1002-er.964; Ruan D., 1997, INTELLIGENT HYBRID S; Simmonds P, 2006, ASHRAE TRAN, V112, P368; SPERCHER P, 1995, ASHRAE T, V101, P711; STRAND RK, 2004, ENERG BUILDINGS, V36, P1; Visual DOE 4.0 software, 2005, VIS DOE 4 0 SOFTW; Walton G.N., 1980, ASHRAE T, V86, P190; Wang SW, 2000, BUILD ENVIRON, V35, P471, DOI 10.1016-S0360-1323(99)00032-3; Wang SW, 2008, HVACandR RES, V14, P3, DOI 10.1080-10789669.2008.10390991; Xu J, 2005, HVACandR RES, V11, P215, DOI 10.1080-10789669.2005.10391135; Zhang Q, 2005, ASHRAE TRAN, V111, P63; Zhou XT, 2007, HVACandR RES, V13, P769, DOI 10.1080-10789669.2007.10390985; Zhou XT, 2007, HVACandR RES, V13, P785, DOI 10.1080-10789669.2007.1039098676
Optimal location and thickness of insulation layers for minimizing building energy consumption
No full textThis work aims to optimize the position and thickness of insulation layers in building external wall for climates in the coastal Mediterranean zone and in the inland plateau of Lebanon. A space and an air-conditioning system performance models are developed to predict the space and system loads and associated thermal comfort of occupants. A genetic algorithm is used for the optimization of the life cycle cost of the insulation based on energy load while including the productivity loss associated with thermal discomfort during transient periods. For continuous operation of building HVAC system, adding insulation reduces life cycle cost by 20percent over current thermal code requirements. During intermittent operation, locating the insulation at the inner side of the walls results in 15percent reduction in energy load compared to locating it on the outer wall. The optimum thickness varied between 3 cm and 5 cm depending on wall orientation climate season. © 2012 International Building Performance Simulation Association (IBPSA).Al-Sanea S.A., 2001, J THERM ENVELOPE BUI, V24, P275, DOI 10.1106-07E7-FGCJ-MFF7-974W; Al-Sanea S.A., 2002, INT J AMBIENT ENERGY, V23, P115; [Anonymous], 1982, LBL11353 US DEP EN; Bojic M, 2001, ENERG BUILDINGS, V33, P569, DOI 10.1016-S0378-7788(00)00125-0; Bollaturk A., 2006, APPL THERM ENG, V26, P1301; Caldas LG, 2003, J SOL ENERG-T ASME, V125, P343, DOI 10.1115-1.1591803; Chaaban FB, 1998, ENERG POLICY, V26, P487, DOI 10.1016-S0301-4215(98)00011-1; Chow TT, 2002, ENERG BUILDINGS, V34, P103, DOI 10.1016-S0378-7788(01)00085-8; Coley DA, 2002, BUILD ENVIRON, V37, P1241, DOI 10.1016-S0360-1323(01)00106-8; Daouas N, 2011, APPL ENERG, V88, P156, DOI 10.1016-j.apenergy.2010.07.030; El-Fadel M., 2010, ENERG POLICY, V38, P751; Fisk WJ, 1997, INDOOR AIR, V7, P158, DOI 10.1111-j.1600-0668.1997.t01-1-00002.x; Ghaddar N, 2010, INT J ENERG RES, V34, P1328, DOI 10.1002-er.1677; Ghaddar N, 2011, ENERG BUILDINGS, V43, P2832, DOI 10.1016-j.enbuild.2011.06.040; Ghaddar N, 1998, INT J ENERG RES, V22, P523, DOI 10.1002-(SICI)1099-114X(199805)22:6523::AID-ER3733.0.CO;2-R; Ghali K, 2011, INT J HVAC IN PRESS; Houri A, 2005, INT J ENERG RES, V29, P755, DOI 10.1002-er.1086; Huang W, 1997, ENERG BUILDINGS, V26, P277, DOI 10.1016-S0378-7788(97)00008-X; Itani T., 2011, INT J SUSTA IN PRESS; Keblawi A, 2009, ENERG BUILDINGS, V41, P1155, DOI 10.1016-j.enbuild.2009.05.009; Kosonen R, 2004, ENERG BUILDINGS, V36, P987, DOI 10.1016-j.enbuild.2004.06.021; Kossecka E, 2002, ENERG BUILDINGS, V34, P321, DOI 10.1016-S0378-7788(01)00121-9; Lebanese Ministry of Public Works and Transport, 2005, CLIM ZON BUILD LEB; Lebanon Green Building Council, 2011, REV LEB THERM GUID B; Math Works, 2009, MATLAB; Niemela R, 2002, ENERG BUILDINGS, V34, P759, DOI 10.1016-S0378-7788(02)00094-4; Ozel M, 2011, APPL ENERG, V88, P2429, DOI 10.1016-j.apenergy.2011.01.049; Ozel M, 2007, BUILD ENVIRON, V42, P3051, DOI 10.1016-j.buildenv.2006.07.025; Patankar S. V., 1980, NUMERICAL HEAT TRANS; Ruble E., 2011, ENERG POLICY, V39, P2467; Tse W.L., 2007, HVACandR RES, V13, P5; Tsilingiris PT, 2006, ENERG BUILDINGS, V38, P1022, DOI 10.1016-j.enbuild.2005.11.012; Ucar A, 2010, RENEW ENERG, V35, P88, DOI 10.1016-j.renene.2009.07.009; Visual DOE 4.0 software, 2005, VIS DOE 4 0 SOFTW; Wright JA, 2002, ENERG BUILDINGS, V34, P959, DOI 10.1016-S0378-7788(02)00071-3; Zhang H, 2003, HUMAN THERMAL SENSAT32
Simplified heat transport model of a wind-permeable clothed cylinder subject to swinging motion
No full textThe effect of ventilation induced by the swinging motion of a clothed cylinder in uniform wind derived from Ghaddar et al.'s periodic ventilation model is incorporated into Lotens' simple heat resistance network model to predict the mean steady periodic heat loss from the clothed cylinder. Experiments are conducted to measure the sensible heat loss from the inner cylinder for the case of a swinging inner cylinder enclosed within a clothed cylinder at different frequencies of motion and for open and closed clothing apertures at the one end of the clothed cylinder. The heat model predictions of time-averaged steady-periodic sensible heat loss agree well with the experimentally measured values at different swing frequencies between 40 and 80 rpm from experiments conducted in a controlled environmental chamber at T∞ = 25°C and relative humidity (RH) = 50percent (air velocity is less than 0.05 m-s) and in a low-speed wind tunnel (for air speed between 2 and 4 m-s). The model results showed that the rate of heat loss increased with increased ventilation frequency. Heat transfer by ventilation presented more than 50percent of total heat loss from a clothed cylinder at f = 80 rpm in the absence and presence of wind. When accurate ventilation rates of clothed swinging cylinder are estimated from first principles, the simplified heat resistance model predicted the heat loss from the isothermal cylinder surface with reasonable accuracy. The model will be a convenient tool for predicting segmental walking human body heat losses.ALOTHMANI M, 2008, INT J HEAT IN PRESS; [Anonymous], 2007, 11079 ISO; [Anonymous], 2006, 7730 ISO; [Anonymous], 2007, 9920 ISO; [Anonymous], 2002, 7933 ISO; Danielson U, 1993, THESIS ROYAL I TECHN; Fan JT, 2000, INT J HEAT MASS TRAN, V43, P2989, DOI 10.1016-S0017-9310(99)00235-5; FARNWORTH B, 1983, TEXT RES J, V53, P717, DOI 10.1177-004051758305301201; FARNWORTH B, 1986, TEXT RES J, V56, P653, DOI 10.1177-004051758605601101; Fiala D, 2001, INT J BIOMETEOROL, V45, P143, DOI 10.1007-s004840100099; Fu G, 1995, THESIS KANSAS STATE; Ghaddar N, 2005, INT J HEAT MASS TRAN, V48, P3151, DOI 10.1016-j.ijheatmasstransfer.2005.03.001; Ghaddar N, 2003, INT J THERM SCI, V42, P605, DOI 10.1016-S1290-0729(03)00026-7; GHADDAR N, 2008, ASME, V130; Ghali K, 2002, J HEAT TRANS-T ASME, V124, P530, DOI 10.1115-1.1471524; Ghali K, 2002, INT J HEAT MASS TRAN, V45, P3703, DOI 10.1016-S0017-9310(02)00088-1; Ghali K, 2006, J HEAT TRANS-T ASME, V128, P908, DOI 10.1115-1.2241811; Ghali K, 2002, J POROUS MEDIA, V5, P17; GIBSON P, 1996, NATICKTR95004 US ARM, P115; Gibson P, 2006, THERMAL AND MOISTURE TRANSPORT IN FIBROUS MATERIALS, P542, DOI 10.1533-9781845692261.3.542; GIBSON P, 1997, J SOC FIBER SCI TECH, V35, P183; HAVENITH G, 2005, P 12 INT C ENV ERG Y; HAVENITH G, 1990, ERGONOMICS, V33, P67, DOI 10.1080-00140139008927094; HAVENITH G, 1990, ERGONOMICS, V33, P989, DOI 10.1080-00140139008925308; Havenith G, 2004, EUR J APPL PHYSIOL, V92, P636, DOI 10.1007-s00421-004-1113-6; Havenith G, 2002, ENERG BUILDINGS, V34, P581, DOI 10.1016-S0378-7788(02)00008-7; Havenith G, 1999, ANN OCCUP HYG, V43, P339, DOI 10.1016-S0003-4878(99)00052-6; HAVENITH G, 2000, ENV ERGONOMICS, V10, P125; Holmer I, 1995, ANN OCCUP HYG, V39, P809, DOI 10.1016-0003-4878(95)00041-0; Huizenga C, 2001, BUILD ENVIRON, V36, P691, DOI 10.1016-S0360-1323(00)00061-5; JONES BW, 1992, ASHRAE TRAN, V98, P189; Kerslake D.M., 1972, STRESS HOT ENV; LI Y, 1992, TEXT RES J, V62, P211; Lotens WA, 1993, THESIS TNO I PERCEPT; Salloum M, 2007, INT J THERM SCI, V46, P371, DOI 10.1016-j.ijthermalsci.2006.06.017; Tanabe S, 2002, ENERG BUILDINGS, V34, P637, DOI 10.1016-S0378-7788(02)00014-2; Zhang H., 2003, THESIS U CALIFORNIA; ZHAO J, 1995, THESIS KANSAS STATE67
Energy consumption and feasibility study of a hybrid desiccant dehumidification air conditioning system in Beirut
No full textThis work studies the economic feasibility of integrating a rotary solid desiccant wheel with the conventional vapor compression air-conditioning system in the city of Beirut. To increase the economic practicality of such a hybrid system, the combined system utilizes the heat dissipated by the condenser and natural gas heat energy in regenerating the desiccant wheel. A heat and mass transfer desiccant model is developed to study the hourly performance of the hybrid system when used in air conditioning a typical auditorium (150 m2) over the entire cooling season. The economic performance of the hybrid system is compared with the conventional air-conditioning system while varying the number of occupants in the auditorium from 10 to 100 to change the sensible heat ratio from 0.53 to 0.27 and the percentage of the outside fresh air from 25percent to 100percent. The conventional system cooling load range was between 9.2 kW and 63.4 kW for the cases simulated in this work, while the vapor compression subsystem varied in the hybrid system from 7.4 kW to 32.7 kW. It was found that the economic viability of the hybrid system increases with lower sensible heat ratio (SHR) and increases in the percentage of outside air. The payback period varied from two years for a high occupancy system to seven years for a low occupancy system.ALBERS WF, 1991, ASHAE T, V99, P603; AYOUB M, 2005, P 3 INT C EN RES DEV, P521; BUZWEILER U, 1993, ASHRAE T, V99, P503; COLLIER RK, 1990, ASHRAE TRAN, V96, P1262; Fang L, 1998, INDOOR AIR, V8, P80, DOI 10.1111-j.1600-0668.1998.t01-2-00003.x; Ghaddar N., 1998, INT J ENERG RES, V32, P523; MECKLER M, 1995, ASHRAE T S; PENG CSP, 1984, J SOL ENERG-T ASME, V106, P133; Visual DOE 4.0 software, 2005, VIS DOE 4 0 SOFTW; Yong L, 2006, J SOL ENERG-T ASME, V128, P77, DOI 10.1115-1.2148977; Zhang XJ, 2003, APPL THERM ENG, V23, P989, DOI 10.1016-S1359-4311(03)00047-444
Optimized solar-powered liquid desiccant system to supply building fresh water and cooling needs
No full textThis paper studies the feasibility of using a solar-powered liquid desiccant system to meet both building cooling and fresh water needs in Beirut humid climate using parabolic solar concentrators as a heat source for regenerating the liquid desiccant. The water condensate is captured from the air leaving the regenerator. An integrated model of solar-powered calcium chloride liquid desiccant system for air dehumidification-humidification is developed. The LDS model predicted the amount of condensate obtained from the humid air leaving the regenerator bed when directed through a coil submerged in cold sea water. An optimization problem is formulated for selection and operation of a LDS to meet fresh water requirement and air conditioning load at minimal energy cost for a typical residential space in the Lebanon coastal climate with conditioned area of 80m2 with the objective of producing 15l of fresh drinking water a day and meet air conditioning need of residence at minimum energy cost. The optimal regeneration temperature increases with decreased heat sink temperature with values of 50.5°C and 52°C corresponding to sink temperatures of 19°C and 16°C. © 2011 Elsevier Ltd.Afandizadeh S, 2001, APPL THERM ENG, V21, P669, DOI 10.1016-S1359-4311(00)00072-7; Al-Faifi H, 2010, DESALINATION, V250, P479, DOI 10.1016-j.desal.2009.06.077; Al-Farayedhi AA, 1999, ENERG CONVERS MANAGE, V40, P1405, DOI 10.1016-S0196-8904(99)00036-9; Al-Sulaiman FA, 2007, APPL THERM ENG, V27, P2449, DOI 10.1016-j.applthermaleng.2007.02.010; *ARCH EN CORP, 2005, VIS DOE 4 0 SOFTW; Arens E, 1998, ENERG BUILDINGS, V27, P45, DOI 10.1016-S0378-7788(97)00025-X; *ASHRAE, 2005, HDB FUNDAMENTALS ASH; Bourouni K, 2001, DESALINATION, V137, P167, DOI 10.1016-S0011-9164(01)00215-6; Braun J.E., 1989, ASHRAE T, V95, P164; Chua KJ, 2010, APPL ENERG, V87, P3611, DOI 10.1016-j.apenergy.2010.06.014; Duffie J., 2003, SOLAR ENG THERMAL PR; Eicker U, 2010, APPL ENERG, V87, P3735, DOI 10.1016-j.apenergy.2010.06.022; Elsarrag E, 2008, SOL ENERGY, V82, P663, DOI 10.1016-j.solener.2008.01.006; ERTAS A, 1991, J ENERG RESOUR-ASME, V113, P1, DOI 10.1115-1.2905774; Ettouney H, 2005, DESALINATION, V183, P341, DOI 10.1016-j.desal.2005.03.039; FANGER BO, 1982, THERMAL COMFORT ANAL; Fumo N, 2002, SOL ENERGY, V72, P351, DOI 10.1016-S0038-092X(02)00013-0; Gandhidasan P, 2004, SOL ENERGY, V76, P409, DOI 10.1016-j.solener.2003.10.001; Ghaddar N., 1998, INT J ENERG RES, V32, P523; Ghaddar N, 2003, INT J ENERG RES, V27, P1317, DOI 10.1002-er.945; Hafez A., 2002, DESALINATION, V153, P335; HOLMAN JP, 1997, HEAT TRANSFER, P488; Liping W, 2007, BUILD ENVIRON, V42, P4006, DOI 10.1016-j.buildenv.2006.06.027; MESSAOUDENE A, 2010, RENEW ENERG, V35, P629; Mossolly M, 2008, ASHRAE T, V143, P541; MOTTA SFY, 2000, P 2000 INT REFR C PU, P47; Narayan GP, 2010, RENEW SUST ENERG REV, V14, P1187, DOI 10.1016-j.rser.2009.11.014; Parekh S, 2004, DESALINATION, V160, P167, DOI 10.1016-S0011-9164(04)90007-0; Praene JP, 2011, APPL ENERG, V88, P831, DOI 10.1016-j.apenergy.2010.09.016; Radhwan A. M., 1993, Renewable Energy, V3, DOI 10.1016-0960-1481(93)90130-9; Sozen A, 2005, APPL ENERG, V80, P97, DOI 10.1016-j.apenergy.2004.03.005; Xiong ZQ, 2010, APPL ENERG, V87, P1495, DOI 10.1016-j.apenergy.2009.08.048; Zhai XQ, 2008, APPL ENERG, V85, P297, DOI 10.1016-j.apenergy.2007.07.016; Zhou XT, 2007, HVACandR RES, V13, P785, DOI 10.1080-10789669.2007.1039098623302
Effect of stove asymmetric radiation field on thermal comfort using a multisegmented bioheat model
No full textThe multinode multisegment bioheat model of Salloum et al. [Salloum M, Ghaddar N, Ghali K. A new transient bio-heat model of the human body. In: Proceedings of the ASME 2005 summer heat transfer conference, 17-22 July 2005, San Francisco, Paper no. HT2005-72303] is integrated with a space heat model to study human thermal response when subjected to radiant asymmetry in stove-heated domestic spaces in Lebanon. For any given person position, the overall comfort level is based on Frank et al. model correlations [Frank SM, Srinivasa NR, Bulcao CF, Goldstein DS. Relative contribution of core and cutaneous temperatures to thermal comfort and autonomic responses in humans. Journal of Applied physiology 1999;86(5):1588-93]. The assessment of local comfort level is based on the maximum deviation of the clothed segments skin temperature from the mean skin temperature and its relation to the radiant temperature asymmetry. Experiments were run on human subjects at steady-state conditions to measure the variation of the skin temperature at different locations of the human body segments while standing in an asymmetric thermal radiation field generated by a stove-heating unit. The experiments were conducted to validate the applicability of the bioheat model in predicting skin temperature in asymmetric conditions. The measured skin temperature of various body segments and the radiative asymmetry agreed within ±5percent of values predicted by the bioheat model [Salloum M, Ghaddar N, Ghali K. A new transient bio-heat model of the human body. In: Proceedings of the ASME 2005 summer heat transfer conference, 17-22 July 2005, San Francisco, Paper no. HT2005-72303]. The space heat model and the bioheat model are applied to a case study to predict both overall thermal comfort and local thermal discomfort in a typical radiant heat space at different standing positions of the person. Strong thermal discomfort exists within the vicinity of the stove high-temperature surface. The local discomfort is considered at values of maximum SD1.1 °C derived from consideration of Fanger et al. [Fanger PO, Ipsen BM, Langkilde G, Olesen BW. Comfort limits for asymmetric thermal radiation. Energy and Buildings 1985;8(3):225-36] data of comfort limits and skin temperature measurements for asymmetric thermal radiation. © 2007 Elsevier Ltd. All rights reserved.[Anonymous], 1992, 55 ASHRAE; BERGLUND LG, 1968, ASHRAE T, V93, P497; FANGER BO, 1982, THERMAL COMFORT ANAL; Fanger P. O., 1980, ASHRAE T, V86, P141; FANGER PO, 1985, ENERG BUILDINGS, V8, P225, DOI 10.1016-0378-7788(85)90006-4; Frank SM, 1999, J APPL PHYSIOL, V86, P1588; Gan G, 2001, BUILD SERV ENG RES T, V22, P95, DOI 10.1191-014362401701524154; Ghaddar N, 2006, HEAT TRANSFER ENG, V27, P29, DOI 10.1080-01457630600742480; Ghali K, 2005, INT J GREEN ENERGY, V2, P287, DOI 10.1080-01971520500198825; Hodder SG, 1998, ENERG BUILDINGS, V27, P167, DOI 10.1016-S0378-7788(97)00038-8; HOWEL RH, 1987, RP394 ASHRAE; Huizenga C, 2001, BUILD ENVIRON, V36, P691, DOI 10.1016-S0360-1323(00)00061-5; ISO, 1984, 7730 ISO; Jones B.W., 1992, ASHRAE T, V98; Jones EC, 1998, REC ADV TOB, V24, P3; Markov D., 2002, ANN INT COURSE VENTI, P158; McNall PE, 1970, ASHRAE T, V76, P123; Miriel J, 2002, APPL THERM ENG, V22, P1861, DOI 10.1016-S1359-4311(02)00087-X; SALLOUNI M, 2005, P ASME 2005 SUMM HEA; Smith CE, 1991, THESIS KANSAS STATE; Zmeureanu R, 2003, BUILD ENVIRON, V38, P427, DOI 10.1016-S0360-1323(02)00133-644
Chilled ceiling displacement ventilation design charts correlations to employ in optimized system operation for feasible load ranges
No full textThis paper expands Ghaddar et al. [N. Ghaddar, K. Ghali, R. Saadeh, A. Keblawi, Design charts for combined chilled ceiling displacement ventilation system (1438-RP), ASHRAE Transactions, 143 (2) (2008) 574-587] design charts of combined chilled ceiling (CC) displacement ventilation (DV) system to operating sensible load ranges from 40 W-m 2 to 100 W-m 2. It develops a global correlation of system load and operational parameters, with comfort measured by vertical temperature gradient and indoor air quality measured by the stratification height. The correlations are used for a known transient load profile in generating optimal settings of the CC-DV system operational parameters and associated energy consumption. An example is illustrated to show how the correlation could be used to size the system and to provide optimized control of the CC-DV system operation at low computational cost. Results of the current model are compared to the published case study of an optimized operation based on transient simulations of the space thermal model to achieve minimum operation cost [M. Mossolly, N. Ghaddar, K. Ghali, L. Jensen, Optimized operation of combined chilled ceiling displacement ventilation system using genetic algorithm, ASHRAE Transactions, 143 (2) (2008) 541-554]. The design correlations resulted in good agreement with published data (within 3percent error in energy consumption and average 6percent error in predictions of comfort and stratification height) at 1-4 of the computational time. The presented methodology provides an alternative for using the correlation for supervisory online controllers for the CC-DV system based on physically derived correlations. © 2009 Elsevier B.V. All rights reserved.ASHRAE, 2009, ASHRAE HDB FUND; Ayoub M, 2006, HVACandR RES, V12, P1005, DOI 10.1080-10789669.2006.10391448; Braun J.E., 1989, ASHRAE T, V95, P164; Braun JE, 2002, HVACandR RES, V8, P73, DOI 10.1080-10789669.2002.10391290; CONROY C, 2001, ASHRAE T, V107, P1; Ghaddar N., 2008, ASHRAE T, V143, P574; Ghali K, 2007, INT J ENERG RES, V31, P743, DOI 10.1002-er.1266; House JM, 1995, ASHRAE TRAN, V101, P647; Mitchell M., 1997, INTRO GENETIC ALGORI; Mossolly M, 2008, ASHRAE T, V143, P541; Mundt E., 1996, PERFORMANCE DISPLACE; Nassif N, 2005, HVACandR RES, V11, P459, DOI 10.1080-10789669.2005.10391148; Novoselac A, 2002, ENERG BUILDINGS, V34, P497, DOI 10.1016-S0378-7788(01)00134-7; Rees SJ, 2001, BUILD ENVIRON, V36, P753, DOI 10.1016-S0360-1323(00)00067-6; *SOFTW EXPR INC, 2002, SPSS WIND 11 0 SOFTW; Wang SW, 2008, HVACandR RES, V14, P3, DOI 10.1080-10789669.2008.10390991; ZHANG Y, 2005, THESIS LOUGHBOROUGH; Zhang YP, 2006, IEEE J SEL TOP QUANT, V12, P760, DOI 10.1109-JSTQE.2006.8763110101
Modulated air layer heat amd moisture transport by ventilation and diffusion from clothing with open aperture
No full textA two-dimensional model is developed for the modulated internal airflow, due to walking, in the gap between clothing and skin surface in the presence of clothing apertures. The normal airflow renewing the air layer through the fabric is modeled using the Ghali et al. three-node fabric ventilation model with corrected heat and moisture transport coefficients within the fabric voids to include the diffusion-dominated transport processes in the fabric at low normal flow rates that occur near the open aperture. The parallel flow is induced by a periodic pressure difference between environmental pressure at the aperture of the clothing system and trapped air layer pressure. The parallel flow in the trapped air layer is assumed to be locally governed by the Womersley solution of time-periodic laminar flow in a plane channel. The two-dimensional (2D) model that uses, in the parallel direction, the Womersley flow of the trapped air layer has predicted significantly lower flow rates than a model based on an inertia-free quasi-steady Poisueille flow model (valid only at low ventilation frequencies). In addition, the model predicted lower sensible and latent heat losses from the sweating skin in the presence of open apertures in the clothing system. The percentage drop in total heat loss due to open aperture is 7.52percent, and 2.63percent, at ventilation frequencies of 25, and 35 revolution per minute, respectively. The reported results showed that under walking conditions, a permeable clothing system with an open aperture reduced heat loss from the skin when compared to a normal ventilation model (closed aperture). These results were consistent with previously published empirical data of Lotens and Danielsson on air layer resistance for open and closed apertures in high air permeable fabrics. Copyright © 2005 by ASME.ASTM, 1996, D73796 ASTM; DANIELSSON U, 1993, THESIS ROYAL I TECHN; FARNWORTH B, 1986, TEXT RES J, V56, P653, DOI 10.1177-004051758605601101; GAGGE AP, 1986, ASHRAE T B, V2; Ghaddar N, 2003, INT J THERM SCI, V42, P605, DOI 10.1016-S1290-0729(03)00026-7; Ghali K, 2002, J HEAT TRANS-T ASME, V124, P530, DOI 10.1115-1.1471524; Ghali K, 2002, INT J HEAT MASS TRAN, V45, P3703, DOI 10.1016-S0017-9310(02)00088-1; GHALI K, 2004, P INT C THERM ENG TH; Ghali K, 2002, J POROUS MEDIA, V5, P17; HAVENITH G, 1990, ERGONOMICS, V33, P67, DOI 10.1080-00140139008927094; HAVENITH G, 1990, ERGONOMICS, V33, P989, DOI 10.1080-00140139008925308; HOLMAN JP, 1997, HEAT TRANSFER, P488; Hyland R.W., 1983, ASHRAE T, V89, P500; JONES BW, 1993, ASHRAE T 1, V98, P189; JONES BW, 1990, P INT C ENV ERG AUST, P66; JONES BW, 1985, P CLIMA 2000 WORLD C, V4, P1; LAMOREUX LW, 1971, B PROSTHET RES, P3; Li Y, 1998, TEXT RES J, V68, P389, DOI 10.1177-004051759806800601; LOTENS W, 1993, THESIS TNO I PERCEPT, P34; McCullough EA, 1989, ASHRAE T, V95, P316; Morton W.E., 1975, PHYS PROPERTIES TEXT; Straatman AG, 2002, PHYS FLUIDS, V14, P1938, DOI 10.1063-1.1476673; WOMERSLEY JR, 1955, PHILOS MAG, V46, P199; WOMERSLEY JR, 1957, 56614 TR WADC AER RE79
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