Study of the Thermal-Hydraulic Characteristics of a Printed Circuit Heat Exchanger Using a Novel Iterative Inversion Method Combined with Genetic Algorithm

Abstract

Printed circuit heat exchangers are getting more and more applications in various energy systems. Detailed data monitoring is essential to understand their operation situations in real time. Nevertheless, the commonly monitored parameters are inadequate to evaluate the local flow and heat transfer characteristics when the fluid undergoes an obvious property variation in the channel. In this work, a measurement system for printed circuit heat exchangers similar to those in industrial applications was set up to study the thermal-hydraulic characteristics of supercritical CO2 with non-linear physical properties. The experimental results show that the heat transfer coefficient can be increased by 82.9–109.6% when the mass flow rate increases from 0.15 to 0.42 kg/s. By comparison, the heat transfer coefficient can be increased by 70.7% when the fluid state approaches the critical point. A novel iterative inversion method was proposed to deduce the coefficients of the heat transfer and friction factor correlations based on the collected fundamental parameters. The deviations of the heat transfer rate and friction coefficient between the measured data and the predicted results by the derived correlations were both within 10%, indicating the feasibility and reliability of the inversion method.