ASHRAE Insights

1256-RP, Thermophysical Properties of R-245fa

R-245fa is a substitute for CFC-11 in the field of air-conditioning, especially in low pressure water chillers typically used in large building air conditioning. The current lack of consistent data on thermophysical properties of R-245fa is one impediment of wider use of this ozone friendly refrigerant. An ASHRAE research project identified and addressed deficiencies and gaps in existing reference data. The results of this research project will contribute to designing of effective refrigerant machinery by improving reference data on the basic properties of R-245fa such as the parameters of liquid-vapor transitions, volumetric behavior, and thermal conductivity.

A technical paper (Vol. 111(2), #4820) on this project was presented at the 2005 Annual Meeting.

1256-RP was sponsored by TC 3.1, Refrigerants and Secondary Coolants. The principal investigator was Alexandre Grebenkov with the Belarus National Academy of Sciences.

1262-RP, Relate Air Quality and Other Factors to Comfort
And Health Related Symptoms Reported by Passengers and Crew On Commercial Transport Aircraft (Part 1)

An ASHRAE research project investigated the potential link between perceived health symptoms and discomfort and aircraft cabin environmental conditions and human factors. A measurement system, protocol, and survey tool were developed. The tools were pilot tested and validated on four commercial aircraft flights to establish a methodology for use on a much larger scale in the next phase of this research. Three battery powered carry-on instrument packages were developed as were two interrelated questionnaires to assess passenger and crew perceptions of health and comfort in the cabin environment.

A technical paper was submitted for presentation in a future edition of the ASHRAE HVAC&R Research.

1262-RP was sponsored by TC 9.3, Transportation Air Conditioning. The principal investigator was Chet Spicer with Battelle Memorial Institute.

1074-RP, Determination of the Dielectric Properties
Of Refrigerants

Current dielectric property data for refrigerants are scarce and incomplete. As the trend progresses towards the use of HCFC and HFC refrigerants and mixtures, the need for a comprehensive resource on the electrical properties of these refrigerants becomes necessary for design of smaller and more efficient compressors and motors. An ASHRAE research project measured dielectric constant, dissipation factor and breakdown voltages for 17 different refrigerants. As new refrigerants are utilized and equipment design changes, the data resulting from this project will help ensure the design of reliable units and help to predict electrical losses.

A technical paper (Vol. 111(1), #4744) on this project was presented at the 2005 Winter Meeting.
1074-RP was sponsored by TC 3.1, Refrigerants and Secondary Coolants. The principal investigator was Andy Gbur of Intergral Services.

1088-RP, Coordinate and Analyze Inter-Laboratory Testing
Of Filters under Standard 52.2 to Determine Adequacy
Of Apparatus Qualification Tests

ASHRAE Standard 52.2 is a method of test standard that details the procedure to measure filtration efficiency of general ventilation air filters. A filter’s MERV is derived from the test results. An ASHRAE research project tested filters at eight laboratories to study the repeatability and reproducibility of Standard 52.2. The research results showed the measurements were free of large discrepancies but the degree of scatter illustrated that there is room for improvement. The final report makes nine recommendations for improvements to the standard ranging from adding procedures and specifications to ensure leak-free filter installation to clarifying the required specifications of the particle counter design.

A technical paper was submitted for presentation at a future ASHRAE Meeting.

1088-RP was sponsored by TC 2.4, Particulate Air Contaminants and Particulate Contaminant Removal Equipment. The principal investigator was James Hanley of the Research Triangle Institute.

1116-RP, Pressure Loss Coefficients of 6, 8, and 10-inch Steel Fittings

A recently completed ASHRAE research project performed 1,256 tests to evaluate head loss coefficient values for 6, 8, and 10 inch steel pipe fittings. Sixty different fittings from four manufacturers were tested including 90° long elbows, reducing and expanding elbows, tees, reducing tees, concentric reducers and expanders. The paper recommends values for head loss coefficients to be used for designs and analyses as well as in ASHRAE publications.

A technical paper was submitted for presentation at a future ASHRAE Meeting.

1116-RP was sponsored by TC 6.1, Hydronic and Steam Equipment Systems. The principal investigator was Omid Mosheni of the University of Minnesota.

1237-RP, Interactive Web-based Owning
And Operating Cost Database

The most commonly referenced source for HVAC equipment service life is Chapter 36 of the 2003 HVAC Applications Handbook volume. A recently completed ASHRAE research project provides an ongoing source of actual HVAC equipment service life data through development of an interactive Web-based database for a variety of building types and HVAC systems. The database was seeded a data set of 163 office buildings. The long-term intent is to encourage the ASHRAE community to contribute their own service life data to further expand the utility of the tool. This input will allow the comparative analysis of many HVAC system types in a broad variety of applications. The final report provides a characterization and analysis of the initial data set.

Technical papers (Vol. 112(1), #4828 & 4829) on this project were presented at the 2006 Winter Meeting and are now available.

1237-RP was sponsored by TC 7.8, Owning and Operating Costs. The principal investigator was Barry Abramson with Servidyne.

1202-RP, Effect of Appliance Diversity and Position
On Commercial Kitchen Hood Performance

The varied use and placement of commercial kitchen appliances under a kitchen exhaust hood can have a pronounced effect on the hood performance. A recently completed project attempts to quantify the impact of this appliance diversity on the minimum exhaust airflow to ensure capture and containment. Appliances typically found in a commercial kitchen were testing in various combinations under a 10-foot long by 4-feet deep, wall-mounted canopy hood. The new research validated some general design rules of thumb and questioned others. A final report details these design conclusions as well as recommends adjustments to heat gain values in the Fundamentals volume of the Handbook and ventilation rates ASHRAE Standard 154. This research will is useful as best practices for designers, installers, and operators.

Technical papers (Vol. 112(1), CH-06-08-02 & CH-06-08-03) on this project were presented at the 2006 Winter Meeting and are now available.

1202-RP was sponsored by TC 5.10, Kitchen Ventilation. The principal investigator was Richard Swierczyna with Architectural Energy Corporation.

1239-RP, Distribution of Water between Vapor And Liquid Phases of Refrigerants

Moisture is an undesired contaminant in refrigeration systems, with potential to cause physical and chemical damage to the system. A completed project provides information necessary to better assess and correct moisture control problems in these systems. The project presents equilibrium constants determined for ten refrigerants to assist in the design process. Only three of these refrigerants had been presented in the ASHRAE Handbook previously. This new research will help to refrigeration system designs to quickly address the moisture situations for remedy or allow the implementation of a longer-term preventative solution.

A technical paper (Vol. 112(1), CH-06-14-01) on this project was presented at the 2006 Winter Meeting and is now available.

1239-RP was sponsored by TC 3.3, Contaminant Control in Refrigeration Systems. The principal investigator was Andy Gbur of Intertek Testing Services.

1246-RP, Optimization of Cryosurgical Probes For Cancer Treatment

Cryosurgery is a localized medical procedure in which cryogenic temperatures are applied to undesirable tissue, typically cancerous, in order to kill it. Recently completed ASHRAE research helps to improve the cryosurgical probes used by developing a design method for these cryosurgical systems. The method used considers the Joule-Thomson cycle to identify optimal refrigerant mixtures and operating parameters for a given cryoprobe geometry design. Design charts are presented so that the cryoprobe design method developed for a single heat exchanger geometry may be applied to any cryoprobe with a known heat exchanger conductance and area.

A technical paper (Vol. 10(2), October 2004) on this project was published in the ASHRAE HVAC&R Research Journal.

1246-RP was sponsored by TC 10.4, Ultra Low Temperature Refrigeration and Cryogenics. The principal investigator was Gregory Nellis of the University of Wisconsin.

The final reports for these projects are available for $24 for ASHRAE members and the ASHRAE Transactions papers are available for $5 for ASHRAE Members at www.ashrae.org/bookstore.