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Comparison of an R22 and an R410A Air Conditioner Operating at High Ambient Temperatures.



William D. Walton, Kathy A. Notarianni


Prediction of the DETACT-QS and LAVENT computer fire models are compared to temperature measurements made during the calibration of the fire detection system in a military aircraft hanger. Two 3.34 m2 isopropyl alcohol pool fire tests of 60 second duration were conducted in the 37 m by 40 m by 14 m high main hanger bay. Brass disks with a known thermal response time index (RTI) were used to simulate the thermal element in a sprinkler or heat detector. Measurements were made of centerline plume temperatures, and ceiling jet gas and disk temperatures at radial distances of 0, 2.7, 5.5, 8.2, and 11.0 m from the centerline of the fire, 380 mm below the ceiling. At a radial distance of 5.5 m, measurements of ceiling jet gas temperatures were also made 150 and 610 mm below the ceiling. Comparisons of predictions and measurements demonstrate some of the strengths and weakness of DETACT-QS and LAVENT for this fire scenario.
NIST Interagency/Internal Report (NISTIR) - 4947
Report Number


computer models, ceiling jets, temperature, aircraft hangars, building technology, detector response, fire models, fire plumes, fire tests, pool fires, response time, sprinkler response


Walton, W. and Notarianni, K. (1993), Comparison of an R22 and an R410A Air Conditioner Operating at High Ambient Temperatures., NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed April 16, 2024)
Created January 1, 1993, Updated November 10, 2018