Optimization of a Zigzag-channel printed circuit heat exchanger for supercritical methane flow

Abstract

Printed circuit heat exchanger (PCHE) is a compact plate heat exchanger that etches microchannels on plates by chemical etching method and exploits bonding force between the atoms to achieve diffusion bonding. It has the promising applications in the fields of floating liquefied natural gas, nuclear reactor, hydrogen energy, etc. The influence of structural parameters on flow and heat transfer characteristics in a Zigzag-channel PCHE was investigated using supercritical methane as flow media. Three-dimensional turbulent steady numerical method was determined and verified through the SST k-ω turbulent model in FLUENT platform. The influence mechanism of structural parameters on flow and heat transfer characteristics was analyzed from temperature distribution, turbulent dissipation rate, vortex vector, turbulent intensity and helicity. The results indicated that the worse flow and better heat transfer performance exhibited under the condition with small channel diameter, small pitch and large bending angle. Meanwhile, the optimization analysis was also conducted though the coupling consideration of flow and heat transfer performances of PCHE using thermal performance factor (TPF). The optimum channel was obtained with the diameter, channel pitch, and bending angle of 1.427 mm, 24.6 mm, and 15° respectively, in scope of this study. The optimum structure parameters obtained herein will be instructive in the design of PCHE.