Effect of Plate orientation in a Cross-Flow Heat Exchanger with Metallic Finned Plates using CFD analysis

Abstract

Heat exchangers have become an integral part of our modern life from boilers in power generation industries to refrigeration systems in our households. Its main utilizations include evaporation, condensation, cooling and heating of fluids to achieve numerous thermal outputs, which are the desired outcomes of various thermodynamic cycles. Heat exchangers can be classified into parallel flow, counter flow, cross-flow and hybrid flow types, of which cross-flow is a type worth investigating for its higher efficiencies depending on the surface area it covers. This paper aims to dive into the possibilities of modifying a cross-flow type HX through analysis and comparison of the angular positions of metallic finned plates placed around the tubes. The objective of this analysis is to find a more efficient design among the conventional HX, which comprises of metallic plates with integrated fins placed in various angular positions along the fluid flow direction instead of conventional straight ones, that has the potential to facilitate more convection heat transfer and increase the system efficiency if implemented. The investigation will be conducted through CFD analysis in ANSYS Fluent, using hot and cold fluids to observe the rate of heat transfer between them as they circulate throughout the HX. The inlet and outlet temperature data of the fluids will be recorded, along with graphs showing the outlet temperature variation with each orientation change of the plates used in the HX design, thus, facilitating the final verdict on the heat transfer efficiency of these models. The generated data and graphs will be analyzed to compare the output temperatures of both hot and cold fluids, which will provide a logical illustration of the heat transfer capacity of the HX models with varying plate orientation, enabling to adopt a better design in heat transfer applications for higher efficiency and better feasibility.