The effect of fin profile on the thermal performance in finned tube heat exchangers

• Main Authors: Chong-Yan Chen, 陳崇言
• Other Authors: Wen-Jeng Chang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/35585671123921673550

碩士 === 逢甲大學 === 機械工程學所 === 95 === Numerical methods are performed to evaluate the effects of fin profile on the thermal performance in finned tube heat exchangers with 3 dimensional steady state. The fin material is steel. FLUENT, a canned software, was utilized for numerical simulation in the study to investigate the heat transfer of different inlet velocity, different finned tube distance, different arrangement of tube rows and the 3 dimensional profile of fins are rectangular, parabolic, and circular. Numerical results indicate the better heat transfer will happened on small finned tube distance, but increasing pressure drop. When the velocity of flow increases, the heat flux line is not a round ring. The temperature change of fins from inlet to first tube is biggest, but the temperature change of fins from second to third tube is not obviously with bigger finned tube distance. It has the best heat transfer on circular fins, but it has the bad heat transfer on rectangular fins. Circular and parabolic fins have larger pressure drop than rectangular fins. No matter the profile of fins, the heat transfer gets better while Reynolds Number increases, but also increasing pressure drop. No matter the profile of fins, staggered arrangement has better heat transfer than in-line arrangement, but it also has higher pressure drop. The heat transfer of a finned tube heat exchangers is truly affected by the 3 dimensional profile of fins, it has better heat transfer with biggest change of fins radian. The result of this paper can served to be a reference for the designers of heat exchangers.