An Isobaric Fix for the Overheating Problem in Multimaterial Compressible Flows
An Isobaric Fix for the Overheating Problem in Multimaterial Compressible Flows
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DOI：
10.1006/jcph.1998.6129
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发表时间：
1999-01
影响因子：
4.1
通讯作者：
Ronald Fedkiw;A. Marquina;B. Merriman
中科院分区：
文献类型：
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作者：
Ronald Fedkiw;A. Marquina;B. Merriman
在许多感兴趣的问题中，固体物体被视为可压缩流场中的刚体。当这些固体物体与可压缩流场的某些特征相互作用时，可能会产生不精确的解。特别地，当冲击反射离开静止的固体壁边界时，发生公知的“过热效应”，导致温度和密度的过冲，而压力和速度保持恒定（参见，例如，3、7、13、14]）。当可压缩流耦合到移动的固体物体（例如，移动活塞），其中非物理密度和温度过冲可以是累积的并且导致负值。我们考虑一般类的材料界面问题，数值方法可以预测压力和速度充分，但失败的密度和温度的预测。出于总变分的考虑和物理的考虑，我们已经开发了这类问题的一个简单的，但一般的边界条件。这种新的边界条件不会改变数值方法预测的压力或速度，但会以与状态方程一致的方式改变密度和温度，从而产生新的值，使边界处的特定变化量最小化。
In many problems of interest, solid objects are treated as rigid bodies in compressible flowfields. When these solid objects interact with certain features of the compressible flowfield, inaccurate solutions may develop. In particular, the well-known “overheating effect” occurs when a shock reflects off of a stationary solid wall boundary causing overshoots in temperature and density, while pressure and velocity remain constant (see, e.g., 3, 7, 13, 14]). This “overheating effect” is more dramatic when compressible flows are coupled to moving solid objects (e.g., moving pistons), where the nonphysical density and temperature overshoots can be cumulative and lead to negative values. We consider the general class of material interface problems where numerical methods can predict pressure and velocity adequately, but fail miserably in their prediction of density and temperature. Motivated by both total variation considerations and physical considerations, we have developed a simple but general boundary condition for this class of problems. This new boundary condition does not change the pressure or the velocity predicted by the numerical method, but does change the density and the temperature in a fashion consistent with the equation of state resulting in new values that minimize a specific measure of variation at the boundary.