Increasing application of supercritical fluids leads to increased use of numerical simulations to guide designs. However, the impact of Equations of State (EoS) selection on computational cost and accuracy is not well understood. Laminar flow around a heated cylinder is used as a test case. A robust matrix of 99-simulations is used to analyze the flow of carbon dioxide just above the critical point at the isobaric condition of 8 MPa and temperatures between 305 and 390 K. Four EoS were studied: Ideal Gas Law, cubic EoS’s Peng-Robinson and Soave-Redlich-Kwong, and the Span-Wagner EoS. Results were identical for isothermal cases, but for heated or cooled cases, the high-fidelity Span-Wagner EoS simulations presented drastically different wake structures. Compared to the high-fidelity SW EoS, cEoS’s underestimated Nu values by up to 38% and cEoS’s underestimated CD values by 18–42%. The Span-Wagner EoS required only 17% more computation time then the cubic EoS simulations, making the Span-Wagner EoS recommended for engineering design.

超临界流体的越来越多的应用导致更多地使用数值模拟来指导设计。但是，人们还不太了解状态方程（EoS）选择对计算成本和准确性的影响。加热缸周围的层流用作测试案例。使用99模拟的鲁棒矩阵分析在等压8 MPa和温度305至390 K之间在临界点正上方的二氧化碳流量。研究了四种EoS：理想气体定律，立方EoS的Peng-Robinson Soave-Redlich-Kwong和Span-Wagner EoS。对于等温情况，结果是相同的，但是对于加热或冷却情况，高保真度Span-Wagner EoS模拟呈现出截然不同的尾流结构。与高保真SW EoS相比，cEoS的Nu值低估了38％，而cEoS的CD值低估了18-42％。Span-Wagner EoS的计算时间仅比三次EoS仿真多17％，因此建议将Span-Wagner EoS用于工程设计。