An Evaluation of Heat Transfer Enhancement Technique in Flow Boiling Conditions Based on Entropy Generation Analysis: Micro-Fin Tube

摘要

The flow boiling heat transfer is one of the common phenomenon happening in the industries. The micro-fin tubes are one of the geometries widely used to enhance heat transfer rate in boiling condition. The entropy generation analysis is presented with its formulation to find precisely the best operating conditions in micro-fin tubes in terms of geometrical parameters and flow conditions. This analysis shows important aspects of losses in fluid systems undergoing boiling. The losses include thermal loss related to the heat transfer and hydraulic one related to the pressure drop. The relevant terms are described for both of these losses. The optimum tube diameter under specified conditions is found. The effect of different flow conditions such as mass velocity, inlet vapor quality on contribution of pressure drop and heat transfer in entropy generation is discussed. It is discovered that there is a desirable set of conditions of fluid flow and micro-fin geometrical shape for which the minimum entropy generation is reached.