中文摘要：

对预处理后Euler方程在低马赫数流动数值模拟中的收敛特性进行了细致研究。首先采用量级分析法研究了Weiss-Smith预处理方法对低速情形下Euler方程收敛性的影响；然后针对低速情形下预处理后的Euler方程组中各方程的收敛性，提出了一个改进的预处理矩阵。数值模拟结果表明：Weiss-Smith预处理方法可以很好地改善Euler方程在低速流动时的收敛特性，并且改进后的预处理矩阵在连续方程的收敛特性方面效果明显。

英文摘要：

The convergence characteristics of the preconditioned Euler equations at low Mach numbers were studied in this article. An order analysis was conducted to search for the convergence characteristics of Euler equations with Weiss-Smith preconditioner in low speed flow. The convergence characteristics of every equation were studied, and then a new preconditioning matrix was suggested. It is shown that excellent conver-gence rates and solution accuracy of Euler equations are obtained with the Weiss-Smith preconditioner, and the new preoconditioning matrix can improve the convergence characteristics of continuity equations considerably in ultra-low speed flow.