超临界CO2临界流数值模拟 Numerical Simulation of Supercritical CO2 Critical Flow

采用超临界二氧化碳工质的动力转换系统是当前国际能源动力领域研究的前沿热点，分析超临界二氧化碳的临界流动对该系统安全分析十分重要。本文基于FLUENT15.0，对不同长径比和滞止参数下的CO2临界流动进行数值模拟，数值模拟结果与美国威斯康星大学实验结果对比，误差范围在15%到25%之间，验证了软件模拟的适用性。通过获得临界流动发生时管道内热工参数和相态变化，探讨了临界流动机理。数值模拟结果为进一步开展实验研究和理论研究提供支持和参考。 The power conversion system using supercritical carbon dioxide is the frontier of the current international energy and power field. It is very important to analyze the critical flow of supercritical carbon dioxide. Based on FLUENT15.0, the critical flow of CO2 under different aspect ratios and Stagnation parameters is numerically simulated. The numerical simulation results are compared with the experimental results of Wisconsin University, and the error range is between 15% and 25%, which validates the applicability of software simulation. The critical flow mechanism is discussed when the thermal parameters and phase changes of the pipeline are obtained when the critical flow occurs. The numerical simulation results provide support and reference for further experimental research and theoretical research.