Thermal-hydraulic performance analysis of the supercritical fuel printed circuit heat exchanger with zigzag flow channels

Abstract

Abstract Printed Circuit Heat Exchanger (PCHE), which uses the supercritical fuel RP-3 as the cold fluid and the air as the hot fluid, is considered a promising candidate for CCA (Cooled Cooling Air) system heat exchanger selection due to its high compactness and efficiency. In this paper, the numerical method of the supercritical fuel PCHE with Zigzag channels is established, and an experimental system is designed and built to verify the accuracy of the numerical method. The influence of inlet temperature, mass flow rate, and outlet pressure of the fuel on the thermal-hydraulic performance is numerically investigated. The inlet temperature of fuel is ranged from 100 to 500°C, the mass flow rate of fuel is from 6 to 10g/s, and the outlet pressure of fuel is ranged from 3 to 6MPa. The results demonstrate that the fuel exhibits higher heat transfer coefficients and pressure drop caused by higher mean turbulent kinetic energy as the increase of the inlet temperature and mass flow rate. The flow and heat transfer performance of the fuel does not change significantly with pressure change since its thermophysical properties decrease slightly with increased pressure. The flow and heat transfer correlations for the tested PCHE are proposed with the numerical results. The newly developed Fanning friction factor correlation predicts almost 100% of the numerical data within the ±5% error band, and the newly developed heat transfer correlation predicts 94.4% of the numerical data within the ±10% error band.