TY - JOUR T1 - A New Multi-Component Diffuse Interface Model with Peng-Robinson Equation of State and Its Scalar Auxiliary Variable (SAV) Approach AU - Qiao , Zhonghua AU - Sun , Shuyu AU - Zhang , Tao AU - Zhang , Yuze JO - Communications in Computational Physics VL - 5 SP - 1597 EP - 1616 PY - 2019 DA - 2019/08 SN - 26 DO - http://doi.org/ 10.4208/cicp.2019.js60.06 UR - https://global-sci.org/intro/article_detail/cicp/13277.html KW - Peng-Robinson equation of state, multi-component diffuse interface model, scalar auxiliary variable approach, energy stable scheme. AB -

A new multi-component diffuse interface model with the Peng-Robinson equation of state is developed. Initial values of mixtures are given through the NVT flash calculation. This model is physically consistent with constant diffusion parameters, which allows us to use fast solvers in the numerical simulation. In this paper, we employ the scalar auxiliary variable (SAV) approach to design numerical schemes. It reformulates the proposed model into a decoupled linear system with constant coefficients that can be solved fast by using fast Fourier transform. Energy stability is obtained in the sense that the modified discrete energy is non-increasing in time. The calculated interface tension agrees well with laboratory experimental data.