In this report, we discuss the accuracy of flow hoods for residential applications, based on laboratory tests and field studies. The results indicate that commercially available hoods are often inadequate to measure flows in residential systems, and that there can be a wide range of performance between different flow hoods. The errors are due to poor calibrations, sensitivity of existing hoods ...

a This proceedings paper presents a summary of results. For more detailed information, the reader is referred to the peer-reviewed publications to be published in ASHRAE Transactions, June 2010. b

Stratified air distribution systems such as Traditional Displacement Ventilation (TDV) and UnderFloor Air Distribution (UFAD) systems have been known to provide better indoor air quality. This study examined the influence of several key design parameters on air distribution effectiveness by using a validated CFD program. The parameters studied were space type, diffuser number, supply air temper...

Around 18% of global carbon emissions can be attributed to building heating or cooling, driven by the adoption “international” thermal comfort standards such as ASHRAE-55, which imply an homogenous indoor environment. We argue that importation warm climates results in cold discomfort due “overcooling”: a phenomenon anecdotally recognised worldwide but not studied defined systematically. Unlike ...

The recent ASHRAE project, “Updating the ASHRAE/ ACCA Residential Heating and Cooling Load Calculation Procedures and Data” (RP-1199), developed two new residential loads calculation procedures: residential heat balance (RHB), a detailed heat balance method that requires computer implementation, and residential load factor (RLF), a simplified procedure that is hand tractable and suitable for sp...

Office workers' preferences for air movement have been extracted from a database of indoor environmental quality surveys performed in over 200 buildings. Dissatisfaction with the amount of air motion is very common, with too little air movement cited far more commonly than too much air movement. Workers were also surveyed in a detailed two-season study of a single naturally ventilated building....

This paper suggests a method how to predict electric lighting energy savings for photocell controls in daylit spaces taking manual blind control into account. The method predicts lower but supposedly more “realistic” lighting energy savings than conventional simulation approaches. On the other hand, predicted savings are larger than those predicted by ASHRAE 90.1 power adjustment factors. The m...

ansi/ashrae 110-95 protocol is a widely acceptable method to assess the performance of laboratory hoods. in this test, sulfur hexafluoride (sf6) is applied as a tracer gas to quantitatively evaluate the performance of laboratory hoods. the environmentally hostile characteristics of sf6 as well as its cost are the major concerns. in the present study, the substitution of ethylene with sf6 in the...

Sixteen flights had been investigated for indoor air quality (IAQ) on Cathay Pacific aircraft from June 1996 to August 1997. In general, the air quality on Cathay Pacific aircraft was within relevant air quality standards because the average age of aircraft was less than 2 years. Carbon dioxide (CO2) levels on all flights measured were below the Federal Aviation Administration (FAA) standard (3...

In this paper, the performance of three high pressure HFC refrigerants: R-32, R-41 OA, and R-41 08, is compared to that of R-22. R-32 has excellent thermophysical properties as compared to R-41 OA, R-41 08 and R-22. However, R-32 is a flammable refrigerant while R-41 OA and R-41 OB are non-flammable. The performance of these refrigerants is investigated in a residential heat pump at the test co...