关键词: 辅助动力装置, 进/排气系统, 维度缩放, 总体性能, 零维仿真模型, 多维度仿真模型

Abstract: Most existing studies employ zero-dimensional simulation models for the overall performance simulation of the Auxiliary Power Unit (APU), while ignoring the impact of total pressure loss changes in the intake/exhaust system on the overall performance of the APU under different operating conditions. To improve the accuracy of calculation results, a zero-dimensional simulation model AZSM (APU Zero-dimensional Steady Model) and a multi-fidelity simulation model AMSM (APU Multi-dimensional Steady Model) were established. These models were achieved by integrating a high-fidelity three-dimensional Computational Fluid Dynamics (CFD) flow field calculation model with a low-fidelity zero-dimensional simulation model via a fully coupled dimensional scaling method, enabling the integrated calculation of the performance of the APU intake/exhaust system and the APU itself. Based on the aforementioned method, this study conducts computational analysis on typical operating points, compares the results with those from the commonly used commercial software Gasturb, and further analyzes the impact of altitude and speed variations on various parameters. The results show that: at Operating Point 1 (ground static state), the calculation accuracy of both AZSM and AMSM increased by 0.02% compared with the results from Gasturb; at Operating Point 2 (flight state at 30,000 ft altitude), the calculation accuracy of AZSM increased by 12.75%, while that of AMSM increased by 19.42%; at Operating Point 3 (flight state at 40,000 ft altitude), the calculation accuracy of AZSM increased by 8.54%, and that of AMSM increased by 24.271%. These results confirm that the multi-dimensional simulation model AMSM can more accurately calculate the overall performance parameters of the APU under different operating conditions.

Key words: Auxiliary Power Unit, Intake/Exhaust System, Dimension Scaling, Overall Performance, Zero-Dimensional Simulation Model, Multi-dimensional Simulation Model