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Related papers: Shocks and finite-time singularities in Hele-Shaw …

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We study the structure of shocks in clumpy media, using a multifluid formalism. As expected, shocks broaden as they weaken: for sufficiently weak shocks, no viscous subshock appears in the structure. This has significant implications for…

Astrophysics · Physics 2009-11-07 R. J. R. Williams , J. E. Dyson

In this paper we study the stability of the self-similar solutions of the binormal flow, which is a model for the dynamics of vortex filaments in fluids and super-fluids. These particular solutions $\chi_a(t,x)$ form a family of evolving…

Analysis of PDEs · Mathematics 2009-12-17 Valeria Banica , Luis Vega

Various thermodynamical phenomena have occurred with change of pressure and temperature, volume. We can choose these parameters but not these constraints, in order to need the thermodynamics with physical properties in the fields of various…

Analysis of PDEs · Mathematics 2014-12-18 Jun-ichi Koga

We explore self-similar dynamical processes in a spherical isothermal self-gravitational fluid with an emphasis on shocks and outline astrophysical applications of such shock solutions. The previous similarity shock solutions of Tsai & Hsu…

Astrophysics · Physics 2009-11-13 Fu-Yan Bian , Yu-Qing Lou

We revisit and derive the shock-change equations relating the dynamics of a shock wave with the partial derivatives describing the motion of a reactive fluid with general equation of state in a stream-tube with arbitrary area variation. We…

Fluid Dynamics · Physics 2020-05-04 Matei Ioan Radulescu

A plane turbulent mixing in a shear flow of an ideal homogeneous fluid confined between two relatively close rigid walls is considered. The character of the flow is determined by interaction of vortices arising at the nonlinear stage of the…

Fluid Dynamics · Physics 2020-07-15 Alexander Chesnokov , Valery Liapidevskii

A new type of self-similarity is found in the problem of a plane-parallel, ultra-relativistic blast wave, propagating in a powerlaw density profile of the form $\rho \propto z^{-k}$. Self-similar solutions of the first kind can be found for…

High Energy Astrophysical Phenomena · Physics 2024-02-14 Tamar Faran , Andrei Gruzinov , Re'em Sari

This article is devoted to incompressible Euler equations (or to Navier-Stokes equations in the vanishing viscosity limit). It describes the propagation of quasi-singularities. The underlying phenomena are consistent with the notion of a…

Analysis of PDEs · Mathematics 2007-05-23 Christophe Cheverry

We consider experimentally the instability and mass transport of a porous-medium flow in a Hele-Shaw geometry. In an initially stable configuration, a lighter fluid (water) is located over a heavier fluid (propylene glycol). The fluids mix…

Fluid Dynamics · Physics 2015-05-20 Scott Backhaus , Konstantin Turitsyn , R. E. Ecke

In $\R^2$, a symmetric blunt body $W_b$ is fixed by smoothing out the tip of a symmetric wedge $W_0$ with the half-wedge angle $\theta_w\in (0, \frac{\pi}{2})$. We first show that if a horizontal supersonic flow of uniform state moves…

Analysis of PDEs · Mathematics 2020-06-15 Myoungjean Bae , Wei Xiang

It is shown that fifth-order nonlinear dispersion equations from compacton theory admit shock and rarefaction waves. A self-similar gradient blow-up is shown to admit infinitely many similarity extensions beyond blow-up time, meaning…

Analysis of PDEs · Mathematics 2009-11-24 V. A. Galaktionov

We prove that the Cauchy problem is well-posed in a strong sense and in a general setting. Our main result is the construction of an abstract semi-flow for the Hele-Shaw problem within general fluid domains (enabling, for instance, changes…

Analysis of PDEs · Mathematics 2025-09-10 Thomas Alazard , Herbert Koch

We study a Cahn-Hilliard-Hele-Shaw (or Cahn-Hilliard-Darcy) system for an incompressible mixture of two fluids. The relative concentration difference $\varphi$ is governed by a convective nonlocal Cahn-Hilliard equation with degenerate…

Analysis of PDEs · Mathematics 2022-01-05 Cecilia Cavaterra , Sergio Frigeri , Maurizio Grasselli

The general problem of shock formation in three space dimensions was solved by D. Christodoulou in his 2007 monograph: 'The Formation of Shocks in 3-dimensional Fluids'. In this work also a complete description of the maximal development of…

Analysis of PDEs · Mathematics 2015-06-30 Demetrios Christodoulou , André Lisibach

We study the shock propagation in a spatially inhomogeneous gas following an intense explosion. We generalize the exact solution of the Euler equation for the spatio-temporal variation of density, velocity, and temperature to arbitrary…

Statistical Mechanics · Physics 2024-09-27 Amit Kumar , R. Rajesh

Asymptotic analysis of the Hele-Shaw flow with a small moving obstacle is performed. The method of solution utilises the uniform asymptotic formulas for Green's and Neumann functions recently obtained by V. Maz'ya and A. Movchan.…

Fluid Dynamics · Physics 2015-05-13 Gennady Mishuris , Sergei Rogosin , Michal Wrobel

We here analyse numerical simulations of supersonic, hypersonic and magnetohydrodynamic turbulence that is free to decay. Our goals are to understand the dynamics of the decay and the characteristic properties of the shock waves produced.…

Astrophysics · Physics 2007-05-23 Michael D. Smith , Mordecai-Mark Mac Low , Julia M. Zuev

Shock wave theory was first studied for gas dynamics, for which shocks appear as compression waves. A shock wave is characterized as a sharp transition, even discontinuity in the flow. In fact, shocks appear in many different physical…

Analysis of PDEs · Mathematics 2007-05-23 Tai-Ping Liu

We consider the singular limit of a bistable reaction diffusion equation in the case when the velocity of the traveling wave solution depends on the space variable and converges to a discontinuous function. We show that the family of…

Analysis of PDEs · Mathematics 2019-05-24 Cecilia De Zan , Pierpaolo Soravia

The problem of interest in this article are waves on a layer of finite depth governed by the Euler equations in the presence of gravity, surface tension, and vertical electric fields. Perturbation theory is used to identify canonical…

Fluid Dynamics · Physics 2015-01-13 Matthew Hunt , Emilian Parau , Jean-Marc Vanden-broeck , Demetrios Papageorgiou