A DSMC (direct simulation Monte Carlo) simulation using Dynamic Molecular Collision (DMC) model based on Molecular Dynamics (MD) calculation is applied for solving the two-dimensional nonequilibrium hypersonic rarefied flow over a flat plate with angle of leading edge. Numerical results show that nonequilibrium between translational and rotational temperature is obtained behind the leading edge over the plate. Translational and rotational energy distributions in the nonequilibrium flow show a typical distribution which is significantly different from the Maxwell-Boltzmann distribution, and reveal a transition process from the nonequilibrium state to the equilibrium state.

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A shock tube available at the state of initially high temperature is made and it is used for the measurement of the growth rate of a liquid film formed on the endwall surface of the tube in shock wave reflection region. It is found that the shock tube satisfies requirements for the experiment and the liquid film grows uniformly on the endwall surface at high temperature. The condensation coefficient of methanol vapor is determined from the growth rate of the liquid film at normal initial temperatures and 50℃. It is clarified that the condensation coefficient is strongly dependent on thermodynamic nonequilibrium degrees which are defined by the temperature and number density ratios of vapor and liquid at the vapor/liquid interface. For the same temperature and number density ratios, the higher is the liquid temperature, the smaller becomes the condensation coefficient, and it decreases with the increase of the number density ratio.

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In the clinical field, focusing phenomenon of ultrasound is widely applied today, such as Extracorporeal Shock Wave Lithotripsy (ESWL), ultrasonography, and hyperthermia. Although ESWL has been used routinely for the treatment of urolithiasis since 1980's, it also causes acute renal injury by violent collapse of cavitation. To the contrary, the collapse of cavitation by ultrasound focusing can be used for noninvasive lithotrity. It is essential to take a real understanding of the behavior of propagation on ultrasound focusing and the dynamics of cavitation in ultrasound field. To observe focusing phenomenon and cavitation collapse, we made experimental apparatus using piezo-transducer, and numerically simulated the propagation of ultrasound focusing. We observe that ultrasound is plane wave at first, then it gradually takes on nonlinear behavior, and at focus it turns shock wave.

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