polytropic gas sphere

例句：

1. 1.The polytropic gas sphere is a complex system that involves multiple phases of matter.
   多相气体球体是一个涉及多种物质相态的复杂系统。
2. 2.The study of the polytropic gas sphere has significant implications for understanding the behavior of materials under high pressure.
   研究多相气体球体对于理解材料在高压下的行为具有重要意义。
3. 3.In the experiment, the polytropic gas sphere was used to simulate the behavior of a real-world fluid.
   在实验中，多相气体球体被用来模拟真实世界中流体的行为。