【摘要】 以开源软件OpenFOAM为平台，开发出适于跨/超临界射流的模型，以研究跨/超临界条件下的喷雾混合特性。模型基于真实流体状态方程和扩展的压力隐式分割算法(PISO)，并结合雷诺平均(RANS)湍流模型，对跨/超临界条件下的液氮射流进行模拟，重点分析射流的伪沸腾特性。研究结果表明：在跨临界射流伪沸腾发生之前，射流表面形成显著的密度分层可抑制湍流扩散和混合层发展；在超临界射流下，混合层内的密度梯度较小，这导致射流能够更快地达到自相似状态。更多还原

【Abstract】 A CFD model applicable for trans/supercritical jets was developed to study spray mixing characteristics under trans/supercritical conditions using the open source software OpenFOAM as a platform. The model was based on the real-fluid equation of state and the extended pressure-implicit with splitting of operators algorithm(PISO), combined with the Reynolds average(RANS) turbulence model, the liquid nitrogen jet under trans/supercritical conditions was simulated, and the pseudo-boiling characteristics were analyzed. The results show that before the pseudo-boiling of the transcritical jet occurs, a significant density stratification on the jet surface can depress the turbulent diffusion and development of the mixing layer. Under supercritical condition, the density gradient in the mixing layer is small, which causes the jet to reach a self-similar state faster.更多还原