Effect of Metal Foam’s Volume on the Performance of a Double Pipe heat exchanger

Abstract

The present numerical study aims to explore the effect of metal foam’s volume on the performance of a double-pipe heat exchanger in comparison with a smooth pipe (HXS). It used water as operating fluid at flow rate 2lpm, the outer stainless steel pipe has outer diameter (Do=60mm) and length (L=609.6mm), and inner copper pipe with outer diameter (do=20mm). The numerical simulation was conducted by ANSYS FLUENT 2020 R2 software and open-cell copper foam (CF) with porosity (0.9) was used. The cases considered in the analysis include a heat exchanger with a complete fill of copper foam (HXF), and  a partial fill heat exchanger. The latter was made by inserting a complete rings of copper foam baffles (CFB) to decrease volume of a CF. Then, the baffles volumes was increased by increasing the thickness and their number.  Three parameters were varied and their influence on performance evaluate criteria (PEC) were investigated. They are pore density (PPI), thickness of baffles (tc), and number of baffles (nob). Results showed that, heat transfer rate (Qave) and the pressure drop (∆p) increased with increase pore density, and well distribution of a CFB increase thermal performance while the pressure drop did not change with use same volume of CF.