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arXiv · 1911.00781

Recovering coercivity for the G-equation in general random media

William M Feldman
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Abstract

The G-equation is a popular model for premixed turbulent combustion. Mathematically it has attracted a lot of interest in part because it is a simple example of a Hamilton-Jacobi equation which is only coercive `on average'. This paper shows that, after an almost surely finite waiting time, coercivity is recovered for the G-equation in a small mean, incompressible, space-time stationary ergodic velocity field. The argument follows ideas from recent work of Burago, Ivanov and Novikov, while significantly weakening the assumption on the velocity field. The waiting time is explicitly characterized in terms of the space-time means of the velocity field and so mixing estimates on the waiting time can easily be derived. Examples are provided.

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William M Feldman. 2019-11-02. Recovering coercivity for the G-equation in general random media. https://arxiv.org/abs/1911.00781

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