This paper studies a Riemann problem for the isentropic Euler equations and addresses two gaps in the literature concerning positive pressures. Such study is made using a product of distributions and a solution concept that extends the classical solution concept. Under certain conditions, even for positive pressures, it is shown that the Riemann problem has solutions, which are \(\delta \)-shock waves. As particular cases, this work examines polytropic gases, pressureless gases, and Chaplygin gases.

中文翻译：

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等熵流体中$$ \ delta $$δ激波的形成

本文研究了等熵Euler方程的Riemann问题，并解决了有关正压力的文献中的两个空白。此类研究是使用分布的产品和扩展了经典解决方案概念的解决方案概念进行的。在某些条件下，即使对于正压力，也证明了黎曼问题具有解，即\（\ delta \） -冲击波。在特定情况下，这项工作将检查多方气体，无压气体和Chaplygin气体。