论文标题
伪光谱方法，用于直接对低操作，可变密度，湍流的数值模拟
A pseudospectral method for direct numerical simulation of low-Mach, variable-density, turbulent flows
论文作者
论文摘要
此处介绍了一种用于可变密度，低操作Navier-Stokes方程的新型算法，该方程扩展了Kim，Moin和Moser（1987）用于不可压缩流的方法。在两个均匀的空间方向上采用了傅立叶表示，并且可以在不均匀方向上使用许多离散化。动量被分解为无裂纹和无卷曲的部分，这使动量方程得以重写，从而消除了解决压力的需求。时间离散化基于明确的，隔离的runge-kutta方法，标量方程被重新重新构成以直接解决状态方程和群众保护方程的冗余。产生方程式的有效，无基质的迭代解决方案允许对大密度比的时间和数值稳定性的二阶精度，这对于高达$ \ sim 25.7 $的比率证明了这一点。
A novel algorithm for the direct numerical simulation of the variable-density, low-Mach Navier-Stokes equations extending the method of Kim, Moin, and Moser (1987) for incompressible flow is presented here. A Fourier representation is employed in the two homogeneous spatial directions and a number of discretizations can be used in the inhomogeneous direction. The momentum is decomposed into divergence- and curl-free portions which allows the momentum equations to be rewritten, removing the need to solve for the pressure. The temporal discretization is based on an explicit, segregated Runge-Kutta method and the scalar equations are reformulated to directly address the redundancy of the equation of state and the mass conservation equation. An efficient, matrix-free, iterative solution of the resulting equations allows for second-order accuracy in time and numerical stability for large density ratios, which is demonstrated for ratios up to $\sim 25.7$.
