Computational fluid dynamics analysis of combined cycle power plant heat exchanger with OpenFOAM® software

Abstract

The heat exchangers application in combined cycle power plants is a key aspect in the thermal and fluid mechanics sciences due to their elevated functionality in industrial processes related to the quality and the efficiency in the power generation. Heat exchangers are employed in thermal processes in order to remove a significant heat flow and to maintain temperature values under different working conditions. Taking into account the above, numerical methodologies have been developed with the aim to study and analyze the heat exchanger performance based on the thermal states of its physical values in space and time. Experimental methods may be applied to create models and describe the flow behavior in function of mass flow rate, pressure, and flow temperature in different measure points of the finite volume. However, it is necessary to apply numerical methods linked to computational tools in order to generate a high flow description into the heat exchanger under real working conditions. Therefore, this paper proposes a numerical analysis of the flow transported into a heat exchanger with computational tools to predict its performance under real Combined Cycle Power Plant conditions through a virtual environment. Random number generator KEpsilon turbulence model and Eulerian – Eulerian multiphase model is coupled in a Computational Fluid Dynamics code to solve the system of the partial differential equations which describes the flow behavior and heat transfer into the heat exchanger, and numerical results have been compared against the experimental model in order to verify the flow prediction of the simulation methodology employed in this particular case. The good agreement reached between the models defines an inexpensive way to evaluate and optimize the heat exchanger performance by means of OpenFOAM software.