超临界射流模型的构建及验证

Construction and Verification of Supercritical Jet Model

利用计算流体动力学(CFD)软件的OpenFOAM开源程序,基于Soave-Redlich-Kwong(SRK)真实流体状态方程和压力隐式分割算法(PISO),考虑气体可压缩性对压力方程的影响,对等温压缩系数进行修正,建立适用于超临界射流的CFD模型,并采用激波管模拟实验和氮气的超临界射流实验对模型进行验证.结果表明:修正后的模型具有较高的预测精度,能够模拟实验结果.

Supercritical injection and combustion processes are prevalent in liquid rockets and hypersonic flight equipment.Under the critical state,the thermophysical and transport properties of the fluid are very sensitive to pressure and temperature,and the ideal state equation is no longer applicable.Based on the OpenFOAM open source program and by using the classical pressure implicit split operator(PISO)algorithm to couple the velocity and pressure,this paper presents a new computational fluid dynamics(CFD)solver for supercritical jet,which incorporates the Soave-Redlich-Kwong(SRK)real-fluid equation of state and takes into account the effect of the isothermal compression coefficient on the pressure equation.And the numerical validity of the model is verified against experiments of a shock tube and supercritical jet.The results show that the new model possesses good prediction accuracy and reproduces the experimental results well.The model can be further extended for applications to transcritical and supercritical spray and mixing under internal combustion engine conditions.