Experimental analysis of nucleate pool boiling of halocarbons refrigerants of low and medium pressure in horizontal surfaces.

Author(s)

Evandro Fockink da Silva

• Document type: Master's Dissertation
• Press: São Carlos.
• Institution: Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD)
• Defense date: 2002-03-18

Examining board members

Jose Maria Saiz Jabardo; Celso Luiz da Silva; Miriam Rocchi Tavares

• Advisor: Jose Maria Saiz Jabardo

Abstract

The present research involves a theorical-experimental study of heat transfer in nucleate pool boiling. Tests included such conditions as halocarbons refrigerants: R11, R123, R141b (low pressure), R12, R22 and R134a (medium pressure); cilyndrical surfaces of cooper, brass and stainless steel with aritmetic surface roughness varying between 0,02 and 3,3 mm; heat flux varying between 0,5 and 120 kW/m2 and reduced pressure from 0,011 to 0,25. Main parameters that influence in nucleate boiling have been compared with those from the literature, showning a clear consistent. New values have been proposed for the coeficient and expoents of the Rohsenow\'s correlation. The correlation, though simple correlates experimental results satisfactorily (AU)