Flow boiling heat characteristics of n-pentane in a mini-channel

Abstract

The experimental study on the flow boiling heat transfer of n-pentane conducted in a mini channel of 1.6 mm inner diameter is presented in this paper. The heat transfer coefficient is measured for mass flux in the range from 250 to 750 kg m-2 s-1 in steps of 250 kg m-2s -1 and the heat flux is varied using an electrical heater arrangement from 1.6 to 3.2 W cm2 (16 to 32 kWm-2). The flow pattern is ensured using established flow pattern maps and confirmed to be predominantly annular flow for all test conditions. The heat transfer coefficient is profoundly influenced by both heat flux and mass flux at higher vapour quality. The experimental heat transfer coefficient is seen to vary between 650 and 1900 W m-2 K-1. The measured pressure drop varies between 0.12 bar and 0.35 bar for the tested condition. © 2013 The Authors. Published by Elsevier Ltd.