Abstract

Advection schemes are important in many branches of computational fluid dynamics. They are used for tracer transport in atmospheric models, where the tracer mixing ratios must remain positive. Many advection schemes employ monotonic limiters, however these can reduce the accuracy of the schemes for smooth data. In this article a commonly used monotonic limiter is modified to make it positive definite (but not strictly monotonic). Testing in multiple dimensions shows that there is improved accuracy over the monotonic limiter, while no negative values are produced.

中文翻译：

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对流问题的正定限制器

摘要

对流方案在计算流体动力学的许多分支中都很重要。它们用于大气模型中的示踪剂运输，其中示踪剂混合比必须保持正值。许多对流方案采用单调限制器，但是这些会降低方案获得平滑数据的准确性。在本文中，对常用的单调限制器进行了修改以使其为正定（但不是严格单调）。多维测试表明，单调限幅器的精度有所提高，而没有负值产生。