### Abstract

For the Cauchy problem associated with a nonlinear, strictly hyperbolic system of conservation laws in one space dimension, we establish a general existence theory in the class of functions with sufficiently small total variation (say less than some constant c). To begin with, we assume that the flux-function f(u) is piecewise genuinely nonlinear, in the sense that it exhibits finitely many (at most p, say) points of lack of genuine nonlinearity along each wave curve. Importantly, our analysis applies to arbitrary large p, in the sense that the constant c restricting the total variation is independent of p. Second, by an approximation argument, we prove that the existence theory above extends to general flux-functions f(u) that can be approached by a sequence of piecewise genuinely nonlinear flux-functions f^{ε}(u). The main contribution in this paper is the derivation of uniform estimates for the wave curves and wave interactions (which are entirely independent of the properties of the flux-function) together with a new wave interaction potential which is decreasing in time and is a fully local functional depending upon the angle made by any two propagating discontinuities. Our existence theory applies, for instance, to the p-system of gas dynamics for general pressure-laws p = p(v) satisfying solely the hyperbolicity condition p′(v) < 0 but no convexity assumption.

Original language | English |
---|---|

Pages (from-to) | 165-244 |

Number of pages | 80 |

Journal | Archive for Rational Mechanics and Analysis |

Volume | 168 |

Issue number | 3 |

Publication status | Published - 2003 Jul |

Externally published | Yes |

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### ASJC Scopus subject areas

- Computational Mechanics
- Mechanics of Materials
- Mathematics(all)
- Mathematics (miscellaneous)

### Cite this

*Archive for Rational Mechanics and Analysis*,

*168*(3), 165-244.

**Existence theory for hyperbolic systems of conservation laws with general flux-functions.** / Iguchi, Tatsuo; LeFloch, Philippe G.

Research output: Contribution to journal › Article

*Archive for Rational Mechanics and Analysis*, vol. 168, no. 3, pp. 165-244.

}

TY - JOUR

T1 - Existence theory for hyperbolic systems of conservation laws with general flux-functions

AU - Iguchi, Tatsuo

AU - LeFloch, Philippe G.

PY - 2003/7

Y1 - 2003/7

N2 - For the Cauchy problem associated with a nonlinear, strictly hyperbolic system of conservation laws in one space dimension, we establish a general existence theory in the class of functions with sufficiently small total variation (say less than some constant c). To begin with, we assume that the flux-function f(u) is piecewise genuinely nonlinear, in the sense that it exhibits finitely many (at most p, say) points of lack of genuine nonlinearity along each wave curve. Importantly, our analysis applies to arbitrary large p, in the sense that the constant c restricting the total variation is independent of p. Second, by an approximation argument, we prove that the existence theory above extends to general flux-functions f(u) that can be approached by a sequence of piecewise genuinely nonlinear flux-functions fε(u). The main contribution in this paper is the derivation of uniform estimates for the wave curves and wave interactions (which are entirely independent of the properties of the flux-function) together with a new wave interaction potential which is decreasing in time and is a fully local functional depending upon the angle made by any two propagating discontinuities. Our existence theory applies, for instance, to the p-system of gas dynamics for general pressure-laws p = p(v) satisfying solely the hyperbolicity condition p′(v) < 0 but no convexity assumption.

AB - For the Cauchy problem associated with a nonlinear, strictly hyperbolic system of conservation laws in one space dimension, we establish a general existence theory in the class of functions with sufficiently small total variation (say less than some constant c). To begin with, we assume that the flux-function f(u) is piecewise genuinely nonlinear, in the sense that it exhibits finitely many (at most p, say) points of lack of genuine nonlinearity along each wave curve. Importantly, our analysis applies to arbitrary large p, in the sense that the constant c restricting the total variation is independent of p. Second, by an approximation argument, we prove that the existence theory above extends to general flux-functions f(u) that can be approached by a sequence of piecewise genuinely nonlinear flux-functions fε(u). The main contribution in this paper is the derivation of uniform estimates for the wave curves and wave interactions (which are entirely independent of the properties of the flux-function) together with a new wave interaction potential which is decreasing in time and is a fully local functional depending upon the angle made by any two propagating discontinuities. Our existence theory applies, for instance, to the p-system of gas dynamics for general pressure-laws p = p(v) satisfying solely the hyperbolicity condition p′(v) < 0 but no convexity assumption.

UR - http://www.scopus.com/inward/record.url?scp=0038336745&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0038336745&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0038336745

VL - 168

SP - 165

EP - 244

JO - Archive for Rational Mechanics and Analysis

JF - Archive for Rational Mechanics and Analysis

SN - 0003-9527

IS - 3

ER -