In this article, we make several comparisons of Riemann solutions of compressible Euler equations in the modified Chaplygin gas state ($p=A\rho -{\rho }^{-1}$) and classical Chaplygin gas state ($p=-{\rho }^{-1}$). Firstly, through the analysis of characteristic method, we construct the Riemann solutions for the modified Chaplygin gas state and compare the Riemann solutions with different coefficients A. Then we obtain the reason of the occurring of delta shock waves in classical Chaplygin gas case, which is the lower bounded of 1-wave curves and the upper bounded of 3-wave curves. Moreover, by comparing the position of simple wave curves between the modified and classical Chaplygin gas state, we find that no matter how small the coefficient A is, there is an initial Riemann data, subject to that the Riemann solutions for modified Chaplygin gas state contain rarefaction waves while the Riemann solutions for classical Chaplygin gas state are delta waves, which is different from the initial expect. Finally, we present a numerical analysis consistent with the theoretical analysis.

在本文中，我们对改进的查普利金气态下可压缩欧拉方程的黎曼解进行了几次比较（$p=\mathrm{一个}\rho -{\rho }^{-1}$) 和经典的 Chaplygin 气体状态 ($p=-{\rho }^{-1}$）。首先，通过特征法分析，构造了修正的查普利金气态的黎曼解，并比较了不同系数A的黎曼解。然后我们得到了经典Chaplygin气体情况下三角洲冲击波发生的原因，即1波曲线的下界和3波曲线的上界。此外，通过比较修正的和经典的查普利金气态的简单波曲线的位置，我们发现无论系数A多么小也就是说，有一个初始的黎曼数据，前提是修正的查普利金气态的黎曼解包含稀疏波，而经典查普利金气态的黎曼解是三角波，这与最初的预期不同。最后，我们提出了与理论分析一致的数值分析。