BGK models for inert mixtures: Comparison and applications

<p style='text-indent:20px;'>Consistent BGK models for inert mixtures are compared, first in their kinetic behavior and then versus the hydrodynamic limits that can be derived in different collision-dominated regimes. The comparison is carried out both analytically and numerically, for the latter using an asymptotic preserving semi-Lagrangian scheme for the BGK models. Application to the plane shock wave in a binary mixture of noble gases is also presented.</p>

Study on Mechanical Properties of Water Mist Acting on Plane Shock Wave

The fine water mist has a significant effect in dealing with fire, gas explosion and other disasters of ships and offshore platforms. In this paper, the correlation formula of water mist acting on the plane shock wave front is derived. By combining with the correlation formula of shock wave tube flow parameters, the classical theory of solving shock wave tube flow parameters is improved, so that it can be applied to the action of water mist on plane shock wave without considering the amount of evaporation. The results of shock wave pressure and wave velocity calculated by the above theoretical formula are compared with experimental data, and the errors are all within 10%, thus verifying the applicability and reliability of the above formula. On this basis, the effects of water mist mass concentration and specific internal energy of droplet after wave on shock wave pressure and shock wave velocity are studied, and different heat absorption methods are compared. The results show that the greater the mass concentration of water mist is, the stronger the weakening effect on the shock wave, indicating that the fine water mist can weaken the strength of shock wave; and specific internal energy of droplet after wave is an important parameter that affects the degree to which the water mist weakens the shock wave. In the case of a small amount of evaporation, sensible heat absorption is the main mechanism for the water mist to weaken the shock wave.