Thermodynamic Second Law Analysis of Forced Convection Film condensation on a Horizontal Elliptical Tube

• Main Authors: Bo-Cong Chen, 陳柏璁
• Other Authors: Sheng-An Yang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/14291180092789539267

碩士 === 國立高雄應用科技大學 === 模具工程系碩士班 === 95 === The goal of this paper is to investigate the entropy generation study of the forced convection film condensation with downward rapid flowing saturated vapors onto a horizontal elliptical cylinder with variable wall temperature. Thermodynamic second law and numerical method perform a theoretical study on this work. The present results showed that the entropy generation is caused by heat transfer irreversibility and film flow friction irreversibility. This study investigates the geometric parameter elliptical, pressure gradient, Reynold number, variable wall temperature parameter A and surface tension to affect local and total entropy generation rate during forced convection film-wise condensation heat transfer process. This article observed that entropy generation increases with augmenting ellipticity, Reynold number and Brinkman number. It revealed that surface tension force influences entropy generation slightly as the value of ellipticity is smaller than 0.9. Furthermore, the ratio of irreversibility is gradually reduced to the minimum value by increasing Reynold number. Then, the heat transfer irreversibility dominates the system of entropy generation much than fluid friction irreversibility.