- Author
-
Womeldorf, C. A.
|
King, M. D.
|
Grosshandler, W. L.
- Title
- Lean Flammability Limit as a Fundamental Refrigerant Property. Interim Technical Report. Phase 1. October 1, 1994-March 31, 1995.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Sponsor
- Air-Conditioning and Refrigeration Technology Inst., Arlington, VA
Department of Energy, Washington, DC
- Report
-
DOE/CE/23810-58,
March 31, 1995,
32 p.
- Distribution
- AVAILABLE FROM National Technical Information Service (NTIS), Technology Administration, U.S. Department of Commerce, Springfield, VA 22161. Telephone: 1-800-553-6847 or 703-605-6000; Fax: 703-605-6900. Website: http://www.ntis.gov
- Contract
- DOE-GRANT-DE-FG02-91CE23810
- Keywords
-
flammability limits
|
refrigerants
|
difluoromethane
|
pentafluoroethane
|
counterflow burner
- Abstract
- Due to the ozone-depleting effects of commonly used chlorofluorocarbon refrigerants, safe environmentally-firendly replacements must be found. HFC-32 (CH₂F₂) and other hydrochlorofluorocarbons are potential candidates; however, in contrast with the CFCs, many of these compounds are flammable. Testing the flammability limits of these hydrochlorofluorocarbons using traditional ASTM E-681 methods has produced a range of limits depending upon the vessel and ignition source used. This project demonstrates the feasibility of defining a fundamental flammability limit of HFC-32, that occurs at the limit of a zero strain rate and is independent of ignition source. Using a counterflow twin-flame burner to define extinction points for different strain rates, an extrapolation to zero strain rate is performed. Using this technique, preliminary results on the lean flammability limit of HFC-32 and the critical flammability ration of HFC-125 (C₂HF₅) in HFC-32 are reported.