An Investigation of Refrigerant Void Fraction in Horizontal, Microfin Tubes

Yashar, D.A.; Wilson, M.J.; Kopke, H.R.; Graham, D.M.; Chato, J.C.; Newell, T.A.

Permalink

https://hdl.handle.net/2142/11888 Copy

Description

Title

An Investigation of Refrigerant Void Fraction in Horizontal, Microfin Tubes

Author(s)

• Yashar, D.A.
• Wilson, M.J.
• Kopke, H.R.
• Graham, D.M.
• Chato, J.C.
• Newell, T.A.

Issue Date

1999-08

Keyword(s)

• two-phase flow
• annular flow
• stratified flow
• micro fin tube
• microgroove tube
• void fraction

Abstract

A series of evaporation and condensation experiments have been performed on horizontal microfin tubes with refrigerants R134a and R410A. Mass flux varied from 75 kg/m2-s to 700 kglm2 -s and average test section quality varied from 5 percent to 80 percent. Zero degree (axial grooving) and 18 degree helix micro fin tube configurations have been examined in both condensation and evaporation. Four tubes were examined (7.3mm and 8.9mm diameters with axial and 18 degree helix angle microfins). Evaporation and adiabatic conditions in microfin tubes generally show similar void fraction trends found in smooth tubes. Condensation void fraction results tend to show a reduction in void fraction relative to smooth tube results, possibly indicating liquid filling of groove regions.

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-145

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/11888

Sponsor(s)/Grant Number(s)

Air Conditioning and Refrigeration Project 74

Owning Collections