{ "id": "2107.11725", "version": "v1", "published": "2021-07-25T04:53:36.000Z", "updated": "2021-07-25T04:53:36.000Z", "title": "Convergence Rate of Hypersonic Similarity for Steady Potential Flows Over Two-Dimensional Lipschitz Wedge", "authors": [ "Jie Kuang", "Wei Xiang", "Yongqian Zhang" ], "categories": [ "math.AP", "math-ph", "math.MP", "physics.flu-dyn" ], "abstract": "This paper is devoted to establishing the convergence rate of the hypersonic similarity for the inviscid steady irrotational Euler flow over a two-dimensional Lipschitz slender wedge in $BV\\cap L^1$ space. The rate we established is the same as the one predicted by Newtonian-Busemann law (see (3.29) in \\cite[Page 67]{anderson} for more details)as the incoming Mach number $\\textrm{M}_{\\infty}\\rightarrow\\infty$ for a fixed hypersonic similarity parameter $K$. The hypersonic similarity, which is also called the Mach-number independence principle, is equivalent to the following Van Dyke's similarity theory: For a given hypersonic similarity parameter $K$, when the Mach number of the flow is sufficiently large, the governing equations after the scaling are approximated by a simpler equation, that is called the hypersonic small-disturbance equation. To achieve the convergence rate, we approximate the curved boundary by piecewisely straight lines and find a new Lipschitz continuous map $\\mathcal{P}_{h}$ such that the trajectory can be obtained by piecing together the Riemann solutions near the approximated boundary. Next, we derive the $L^1$ difference estimates between the approximate solutions $U^{(\\tau)}_{h,\\nu}(x,\\cdot)$ to the initial-boundary value problem for the scaled equations and the trajectories $\\mathcal{P}_{h}(x,0)(U^{\\nu}_{0})$ by piecing together all the Riemann solvers. Then, by the uniqueness and the compactness of $\\mathcal{P}_{h}$ and $U^{(\\tau)}_{h,\\nu}$, we can further establish the $L^1$ estimates of order $\\tau^2$ between the solutions to the initial-boundary value problem for the scaled equations and the solutions to the initial-boundary value problem for the hypersonic small-disturbance equations, if the total variations of the initial data and the tangential derivative of the boundary are sufficiently small.", "revisions": [ { "version": "v1", "updated": "2021-07-25T04:53:36.000Z" } ], "analyses": { "keywords": [ "convergence rate", "steady potential flows", "two-dimensional lipschitz wedge", "initial-boundary value problem", "steady irrotational euler flow" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }