Evaporative Characteristics of R-134a, MP-39, and R-12 at Low Mass Fluxes

Wattelet, J.P.; Chato, J.C.; Souza, A.L.; Christoffersen, B.R.

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https://hdl.handle.net/2142/9736 Copy

Description

Title

Evaporative Characteristics of R-134a, MP-39, and R-12 at Low Mass Fluxes

Author(s)

• Wattelet, J.P.
• Chato, J.C.
• Souza, A.L.
• Christoffersen, B.R.

Issue Date

1993-05

Keyword(s)

refrigerant-side evaporation condensation studies

Abstract

Experimental heat transfer coefficients for R-134a, MP-39, and R-12 are reported herein. Tests were conducted using a single-tube evaporator test facility. The test section used was a 2.43 m (8-foot) long, 7.04 mm (0.277-in) inside diameter, horizontal, smooth copper tube. Heat was applied to the test section using electric resistance heaters. Test parameters were varied as follows: mass flux, 25-100 kg/m2-s (19-76 klbm/ft2-hr); heat flux, 2-10 kW/m2 (600-3200 Btu/hr-ft2); quality, 10-90 percent; saturation temperature, -15 to 5°C (5 to 41°F). The heat transfer coefficients for R-134a were higher than those of R-12 using equivalent mass flux and cooling capacity bases. The heat transfer coefficients for MP-39 were lower than those of R-12 using equivalent mass flux and cooling capacity bases. The correlations of Shah and Kandlikar were compared with the experimental heat transfer coefficients. An empirical correlation was developed for the wavy-stratified flow pattern occurring with the low mass fluxes. For correlating purposes, some high mass flux data with annular flow patterns, reported previously, are also included.

Publisher

Air Conditioning and Refrigeration Center. College of Engineering. University of Illinois at Urbana-Champaign.

Series/Report Name or Number

Air Conditioning and Refrigeration Center TR-35

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/9736

Sponsor(s)/Grant Number(s)

Air Conditioning and Refrigeration Center Project 01

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