Results 201 to 210 of about 5,570,536 (255)

Analytically grounded full-wave methods for advances in computational electromagnetics. [PDF]

open access: yesPhilos Trans A Math Phys Eng Sci
Lucido M   +4 more
europepmc   +1 more source

Riemann Problems with a Kink

SIAM Journal on Mathematical Analysis, 1999
The authors consider the flow of an isothermal gas in a (infinitely) long, thin pipe of constant section, which has one or several kinks in it. They obtain the following model for the flow: \[ \rho_t+ (\rho v)_x= 0,\quad (\rho v)_t+ (\rho v^2+ \rho)_x= -f\sum_i k_i \delta_{x_i} \rho v, \] where \(\delta_{x_i}\) is the Dirac measure located at the ...
Holden, Helge, Risebro, Nils Henrik
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The Riemann Problem

2019
In fluid dynamics, the classical Riemann problem (Riemann 1860) is an initial-value problem for a set of homogeneous PDEs in which the initial data consist of two constant states forming a discontinuity (Toro 1997, 2001; LeVeque 2002; Guinot 2003) (Fig. 8.1). It is a generalization of the dam break problem (Stoker 1957) described in Chap. 6.
Oscar Castro-Orgaz, Willi H. Hager
openaire   +1 more source

The Riemann Problem

2013
This chapter is devoted to study the Riemann problems for scalar conservation laws in one space dimension. In particular, we introduce the definitions of entropy and non-entropy shock waves, rarefaction waves and contact discontinuities by first considering genuinely nonlinear characteristic fields, linearly degenerate characteristic fields and then ...
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A fast solver for riemann problems

Mathematical Methods in the Applied Sciences, 1985
AbstractAn efficient algorithm is presented for solving the Riemann problem for a polytropic gas. It enables the user to compute the solution for all physically reasonable data. The convergence of the algorithm is proved. The accuracy of the solution is limited only by the accuracy of the computer. There is an a‐priori estimation of the required number
E. Halter, E. Martensen
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The Riemann and Riemann-Hilbert Problems

1987
In this chapter the Riemann and the Riemann-Hilbert problems are stated. The first problem is so easy to solve that one might say it is almost obvious. Nevertheless it is discussed here in order to prepare for the exposition of the same question in several variables studied in Chapter 9 which is by no means easy.
openaire   +1 more source

The Riemann Problem

1987
In Chapter I we analyzed the mapping from the functions Ψ(x), to the transition coefficients and discrete spectrum of the auxiliary linear problem. We saw that for both rapidly decreasing and finite density boundary conditions this “change of variables” makes the dynamics quite simple because the time evolution of the transition coefficients ...
Ludwig D. Faddeev, Leon A. Takhtajan
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The Riemann-Hilbert Problem on the Riemann Surface

2019
Here we reduce Eq. ( 15.11) to the Riemann-Hilbert problem. Let us recall that the function \(\hat v_{21}\) is meromorphic in \( \varPi _{-2\varPhi }^\pi \) by ( 15.9) and Lemma 15.2. Consider the strip $$\displaystyle W:=\varPi _{\pi -2\varPhi }^\pi .$$
Alexander Komech, Anatoli Merzon
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The Riemann Problem

2002
In this chapter, we study the Riemann problem for scalar conservation laws. In Section 1 we discuss several formulations of the entropy condition. Then, in Section 2 we construct the classical entropy solution satisfying, by definition, all of the entropy inequalities; see Theorems 2.1 to 2.4.
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ON THE RIEMANN PROBLEM FOR A REACTING MIXTURE OF GASES

Waves and Stability in Continuous Media, 2004
Autore del Libro EDS. MONACO R.; PENNISI S.; RIONERO S.; RUGGERI T.. Titolo del Libro Proceedings "WASCOM 2003" - 12th Conference on Waves and Stability in Continuous Media.
CONFORTO, Fiammetta   +3 more
openaire   +3 more sources

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