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arXiv · 2104.05548

Non Conservative Products in Fluid Dynamics

R. M. Colombo·G. Guerra·Y. Holle
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Abstract

Fluid flow in pipes with discontinuous cross section or with kinks is described through balance laws with a non conservative product in the source. At jump discontinuities in the pipes' geometry, the physics of the problem suggests how to single out a solution. On this basis, we present a definition of solution for a general BV geometry and prove an existence result, consistent with a limiting procedure from piecewise constant geometries. In the case of a smoothly curved pipe we thus justify the appearance of the curvature in the source term of the linear momentum equation. These results are obtained as consequences of a general existence result devoted to abstract balance laws with non conservative source terms.

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R. M. Colombo, G. Guerra, Y. Holle. 2021-04-12. Non Conservative Products in Fluid Dynamics. https://arxiv.org/abs/2104.05548

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