标题： 探索冻结和流使用共形流体力学的精确解 显示英文标题

标题： Exploring freeze out and flow using exact solutions of conformal hydrodynamics

摘要： 精确解流体力学方程为数值流体力学代码提供了宝贵的基准测试，并且也提供了对流体力学流动性质的有用见解。 在本文中，我们介绍了两种新颖的、密切相关的精确解，这些解具有非平凡的速度依赖性，是对著名的古布瑟流解在共形流体力学中的推广。 然后，我们使用其中一个解来探讨在核碰撞的流体动力学模拟中实施冻结过程时选择两种不同标准的结果：恒温冻结与恒Knudsen数冻结。 我们发现，采用我们的精确解，这两种冻结标准之间的差异受到强集体流的影响很大。 我们的结果强调了准确描述具有大流梯度碰撞中的冻结过程的重要性，特别是在小系统中。 显示英文摘要

摘要： Exact solutions to the equations of hydrodynamics provide valuable benchmark tests for numerical hydrodynamic codes and also provide useful insights into the nature of hydrodynamic flow. In this paper, we introduce two novel, closely related exact solutions with non-trivial rapidity dependence which are generalizations of the well-known Gubser flow solution to conformal hydrodynamics. We then use one of our solutions to explore the consequences of choosing between two different criteria for implementing the freeze out process in fluid dynamical simulations of nuclear collisions: freeze out at constant temperature vs. freeze out at constant Knudsen number. We find that, employing our exact solution, the differences between these freeze out criteria are heavily influenced by the presence of strong collective flow. Our results highlight the importance of accurately describing the freeze out process in collisions with large flow gradients, particularly in small systems.