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arXiv · 1712.01705

A stable numerical strategy for Reynolds-Rayleigh-Plesset coupling

Alfredo Jaramillo·Gustavo C. Buscaglia
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Abstract

The coupling of Reynolds and Rayleigh-Plesset equations has been used in several works to simulate lubricated devices considering cavitation. The numerical strategies proposed so far are variants of a staggered strategy where Reynolds equation is solved considering the bubble dynamics frozen, and then the Rayleigh-Plesset equation is solved to update the bubble radius with the pressure frozen. We show that this strategy has severe stability issues and a stable methodology is proposed. The proposed methodology performance is assessed on two physical settings. The first one concerns the propagation of a decompression wave along a fracture considering the presence of cavitation nuclei. The second one is a typical journal bearing, in which the coupled model is compared with the Elrod-Adams model.

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Alfredo Jaramillo, Gustavo C. Buscaglia. 2017-12-04. A stable numerical strategy for Reynolds-Rayleigh-Plesset coupling. https://arxiv.org/abs/1712.01705

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