Heat Exchanger for Exhaust Gas Heat Recovery in a Gas-Based Power Plant: CFD Analysis

Abstract

Energy is one of the most important components of economic growth. But day by day the existing energy resources are depleting at alarming rate. Hence it is necessary to introduce alternate techniques to conserve the energy effectively. With this an attempt has been made to introduce a ceramic heat exchanger with different cross sections.Early Heat Exchangers provide the foundation for numerous applications in process intensification subjected to un satisfactory mass distribution , thermal stresses arising from uneven heating and cooling etc. In order to overcome the difficulties mentioned above, Ceramic materials have been introduced in place of existing materials. Since ceramic materials offer many benefits including high temperature capacity and corrosion resistance. Special and specific design of the heat exchanger surfaces in ceramic heat exchanger surfaces provide equal distribution of inlet flows.
In this project Ceramic heat exchanger of varying tubes were simulated by computational fluid dynamics method(CFD).The multi shaped structure was imported in to fluent 18.2 versions as a physical model. A ceramic monolith heat exchanger is designed to find out the performance and effectivenessof heat transfer. The numerical computation was performed throughout the domain including fluid region in exhaust gas side, ceramic core and fluid region in air side. The entire computation was carried out by using different cross sections viz., Rectangular, Elliptical and Cylindrical duct with air and exhaust in cross flow direction. After comparison of theoretical and numerical computation it is observed that the estimated heat transfer rate in numerical analysis is 15% more than the theoretical analysis