All-speed Roe scheme for the large eddy simulation of homogeneous decaying turbulence

作者：Li, Xue-song^*; Li, Xin-liang

来源：International Journal of Computational Fluid Dynamics, 2016, 30(1): 69-78.

DOI：10.1080/10618562.2016.1156095

• all-speed scheme
• large eddy simulation
• homogeneous decaying turbulence
• Roe scheme
• numerical dissipation

As a type of shock-capturing scheme, the traditional Roe scheme fails in large eddy simulation (LES) because it cannot reproduce important turbulent characteristics, such as the famous k(-5/3) spectral law, as a consequence of the large numerical dissipation. In this work, the Roe scheme is divided into five parts, namely, xi, delta U-p, delta p(p), delta U-u, and delta p(u), which denote basic upwind dissipation, pressure difference-driven modification of interface fluxes, pressure difference-driven modification of pressure, velocity difference-driven modification of interface fluxes, and velocity difference-driven modification of pressure, respectively. Then, the role of each part in the LES of homogeneous decaying turbulence with a low Mach number is investigated. Results show that the parts delta U-u, delta p(p), and delta U-p have little effect on LES. Such minimal effect is integral to computational stability, especially for delta U-p. The large numerical dissipation is due to xi and delta p(u), each of which features a larger dissipation than the sub-grid scale model. On the basis of these conditions, an improved all-speed Roe scheme for LES is proposed. This scheme can provide satisfactory LES results even for coarse grid resolutions with usually adopted second-order reconstructions for the finite volume method.

• 出版日期2016-1-2
• 单位中国科学院; 清华大学; 高温气体动力学国家重点实验室