Flow boiling characteristics of refrigerant mixture R22/R114 in the annulus of enhanced surface tubing

Abstract:

The paper presents an experimental study of flow boiling heat transfer characteristics of refrigerant mixture R22/R114 in the annuli of a horizontal enhanced surface tubing evaporator. The test section had an inner tube bore diameter of 17.3 mm, an envelope diameter of 28.6 mm and an outer smooth tube of 32.3 mm internal diameter. The ranges of heat flux and mass velocity covered in the tests were 5–25 kW/m2 and 180–290 kg/m2/s, respectively, at a pressure of 570 kPa. The enhanced surface tubing data shows a significant enhancement of the heat transfer compared with an equivalent smooth tube depending on the mixture components and their concentrations. Correlations are proposed to pbkp_redict such heat transfer characteristics as the average heat transfer coefficients as well as pressure drops of R22/R114 nonazeotropic refrigerant mixture flow boiling inside enhanced surface tubing. In addition, it was found that the refrigerant mixture's pressure drop is a weak function of the mixture composition. Copyright © 1992 John Wiley & Sons, Ltd.

Año de publicación:

1992

Keywords:

• Refrigeration
• R22/R114
• Refrigerant mixtures
• Heat Transfer

Fuente:

scopus