Optimization of structural parameters and thermal-hydraulic numerical simulation of printed circuit heat exchanger with airfoil fins

Abstract

BackgroundPrinted circuit heat exchanger (PCHE) with airfoil fins is a new type of microchannel heat exchanger with high efficiency and compactness, which has the advantages of high-temperature and high-pressure resistance. In the field of clean energy such as solar, liquefied natural gas and nuclear energy, PCHE with airfoil fins has received widespread attention.PurposeThis study aims to optimize the structural parameters of PCHE with airfoil fins through numerical simulation, and summarize the heat transfer characteristics.MethodsThe computational fluid dynamics program Fluent was employed to design and optimize the structure of PCHE in high temperature molten salt heat exchanger with FNaBe as working fluid. The thermal-hydraulic characteristics such as pressure drop and convective heat transfer coefficient of different airfoil fins arrangements were simulated and compared. Thereafter, orthogonal experimental design was used to find out the arrangement of airfoil fins with the highest energy efficiency. A series of operating conditions were simulated to study the heat transfer and pressure drop characteristics of the best arrangement.ResultsThe arrangement of airfoil fins has the highest energy efficiency when the horizontal distance is 4 mm, vertical distance is 9 mm, and staggered distance is 4 mm. Two correlations were developed to predict heat transfer and pressure drop performance.ConclusionsThis study provides a useful reference for the design of PCHE with airfoil fins in molten salt reactor.

Keywords

• printed circuit heat exchanger
• airfoil fins
• numerical simulation
• orthogonal experimental design
• liquid salt
• thermal-hydraulic characteristics