Flow Boiling Heat Transfer and Pressure Drop Characteristics of a 45/55% by Weight Mixture of R321R125

Villaneuva, T.C.

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https://hdl.handle.net/2142/11043 Copy

Description

Title

Flow Boiling Heat Transfer and Pressure Drop Characteristics of a 45/55% by Weight Mixture of R321R125

Author(s)

Villaneuva, T.C.

Contributor(s)

• Chato, J.C.
• Shimon, R.L.
• DeGuzman, N.M.
• Ponchner, M.
• Sweeney, K.A.
• Rhines, N.L.
• Allen, D.G.
• Hershberger, T.T.

Issue Date

1995-08

Keyword(s)

• R-22 alternatives
• refrigerant-side evaporation condensation studies

Abstract

This study investigates the heat transfer and pressure drop characteristics of a 45/55% by weight mixture of R321R125. For mass fluxes above 150 x 103 Ibm/ft2_h (200 kglm2-s) and heat fluxes below 6400 Btu/ft2_h (20 kW/m2), the experimental Nusselt number is dependent on both heat flux and qUality. An increase in either of these qualities results in anincrease in the Nusselt number. For mass fluxes below 150 x 103 lbm/ft2-h (200 kglm2-s), the Nusselt number is independent of qUality. Pressure drop is dependent on heat flux and quality for the entire range of mass fluxes tested. The accuracy of several two-phase correlations in predicting the experimental data is examined. The Shah [1976] correlation underpredicts the experimental Nusselt number and this is attributed to an underestimation of the convective boiling contribution. The Jung and Radermacher [1989] correlation overpredicts the data. This is due, in part, to the absence of accurate surface tension data for the mixture. The Wattelet [1994] correlation predicts the experimental Nusselt number to within ±20%. The Sousa [1993] correlation predicts the experimental pressure drop to within ± 10%. iii

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-83

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/11043

Sponsor(s)/Grant Number(s)

Air Conditioning and Refrigeration Center Project 37

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