An Investigation of Heat Transfer on Microchannel Heat Exchanger Flow Arrangement with Gas Heating

• Published in: Applied Mechanics and Materials Vol. 145; pp. 262 - 266
• Main Authors: Liu, Tsung Lin, Fu, Ben Ran, Pan, Chin
• Format: Journal Article
• Language: English
• Published: Zurich Trans Tech Publications Ltd 01.12.2011
• Subjects: Evaporator; Micro Heat Exchanger; Micro-Channel
• ISBN: 9783037853245; 3037853247
• ISSN: 1660-9336; 1662-7482; 1662-7482
• DOI: 10.4028/www.scientific.net/AMM.145.262

The present study investigates the effect of flow arrangement on heat transfer characteristics in two-phase microchannel heat exchangers (MCHEs) with gas heating. The microchannel heat exchangers are developed to utilize the exhaust heat from a high-temperature gas product of a methanol reformer (a part of a reformed methanol fuel cell). Co-and counter-current flow types of MCHE are tested. Working fluids in the hot and cold sides are helium and liquid methanol, respectively. For both single-phase flow regions, the experimental results indicate that the actual effectiveness of the counter-current MCHE is higher than that of the co-current MCHE. Both of the actual effectiveness of co-and counter-current MCHEs significantly increases with an increase of cold side mass flux. Moreover, the actual effectiveness for both types of MCHE is less relationship to the hot-side thermal power in single-phase zone. The highest actual effectiveness is about 0.6 and 0.72 for co-and counter-current MCHEs, respectively.