Novel three-dimensional simplified numerical simulation method of a compact precooler for hypersonic precooled air-breathing engine

•A 3D simplified numerical method for a compact tube precooler is developed.•Relative errors between the simplified method and experimental data within 3%.•The effect of non-uniform inflowing on the precooler’s performance are analyzed. The revolutionary thermal cycle of precooled air-breathing engines has led to the application of a compact tubular precooler. A novel three-dimensional simplified numerical simulation method for a compact tube precooler is proposed. The unique aspect of this method is the integration of low-dimensional design method of the precooler with three-dimensional simulation technique. The method includes a segmented model to discretize the precooler into sub-precoolers, with corresponding performance calculation programs for circumferential uniform and non-uniform airflows in the circumferential direction. The heat transfer and pressure drop are then simulated using a combination of the distributed heat source method and porous model. The developed method was verified with previous experiments, and showed good agreement. In addition, the flow and heat transfer characteristics of the precooler were investigated under both circumferential uniform and non-uniform inlet conditions. The results show that the radial total temperature distortion intensity at the outlet of the precooler is 0.087 and 0.073 under uniform and non-uniform inlet conditions, respectively. Additionally, the intensity of circumferential total temperature distortion increases from 0.004 under uniform inlet conditions to 0.029 under non-uniform inlet conditions. Overall, this method provides an accurate evaluation of the precooler during the engineering design phase.