Thermal Analysis of Inlet/Outlet Temperature for Heat Exchanger in Micro Gas Turbine by Numerical Method

Abstract

Recuperator is one type of heat exchanger that is frequently used in a gas turbine to enhance the effectiveness of the system by a two-way method of heat transfer, cooling, and heating. The heat exchanger is a heat transfer system used to transfer thermal energy between two or more fluids available at different temperatures. There is a lack of improvement research for the recuperator that can achieve slight thermal equilibrium for the heat distribution for maximum efficiency of the system. By using ANSYS-FLUENT software with steady-state thermal conduction, the most efficient plate-fin geometrical design and material used for fabrications will be evaluated to enhance the thermal distribution of the heat exchanger, and three inlet temperatures will constantly be supplied by waste heaters which are 200°C, 350°C and 500°C. A distinct boundary condition and mesh sizing need to be emphasized to attain good mesh node value and accurate outcomes. The specific turbulence model, K-Omega SST is chosen for the similarity of its characteristics to be selected with this study criteria. The simulation on steady-state conditions found that copper is better in thermal or heat conductors than aluminium due to the high value of thermal conductivity, k. In terms of design, a triangular type heat exchanger recorded the highest net temperature between the inlet and outlet temperature compared to a rectangular type heat exchanger. In a conclusion, the combination between triangular type design and copper material will produce the best heat exchanger that will be used in the experimental test of the recuperator system.