Characteristic waves and dissipation in the 13-moment-case

Extended thermodynamics derives dissipative, hyperbolic field equations for monatomic gases. One example is the system of the 13-field-case, which is a dissipative extension of the Euler equations. In this paper the system is investigated by solving a Riemann problem. Additionally some model equations are introduced so as to discuss the main properties in a transparent manner. There arises an interesting interplay of the characteristic waves and the dissipation in the system. For the 13-field-case it turns out that not every Riemann problem has a solution, because of the loss of hyperbolicity of the system. Received April 13, 2000