Rarefaction

About: Rarefaction is a research topic. Over the lifetime, 1852 publications have been published within this topic receiving 26943 citations.

A study of the global solutions for quasi-linear hyperbolic systems of conservation laws

Abstract: The present paper is divided into two parts. In Part 1 we deal with a special initial value problem of the gas dynamics system with initial values more general than those in [6]. In this paper we shall prove the existence theorem in the large, the invariability with respeet to t of the properties of the initial values. Moreover, we have studied some properties of the solutions. For example, suppose that the Riemann problem with initial values (u_0(±∞), v_0(±∞)) contains a forward shock wave, then the solution must contain a forward shock wave. The interactions of the shock and rarefaction wave of the same direction are special eases of our initial value problems. In Part 2 we extend the main results of Part 1 to the systems studied in [7].

Inhomogeneous rarefaction of the process gas in a direct current magnetron sputtering system

Abstract: The interactions between energetic particles and the sputter gas in a magnetron sputtering system have strong effects on the growth, structures, and properties of the film. These interactions result in inhomogeneous rarefaction of the gas in the space between target and substrate and affect both the transport of particles towards the substrate and the dynamics of the plasma. A hybrid Monte Carlo and fluid model is developed to simulate three-dimensional (3D) gas rarefaction due to the sputtering of metals in argon, neon, and krypton. The governing equations are solved iteratively in a 3D space with a nonuniform grid (octree). Collision events between the sputtered particles and the process gas are assumed as the dominant source of gas heating; however, the effect of the reflected neutrals is also included in the model. Gas rarefaction profiles have been predicted for different process conditions. Model results compare well with experimental ones. The extent of rarefaction depends on process conditions as ...

High Knudsen Number Molecular Rarefaction Effects in Gas-Lubricated Slider Bearings for Computer Flying Heads

Abstract: Effets de rarefaction moleculaire avec nombre de Knudsen eleve dans une glissiere a gaz (tete oscillante d'ordinateur)

A collection of some controlled surface thermal accommodation coefficient measurements.

Abstract: Thermal accommodation coefficient measurements with rare gases and metals and alkali metal sets

Review of blunt body wake flows at hypersonic low density conditions

Abstract: Recent results of experimental and computational studies concerning hypersonic flows about blunted cones including their near wake are reviewed. Attention is focused on conditions where rarefaction effects are present, particularly in the wake. The experiments have been performed for a common model configuration (70 deg spherically-blunted cone) in five hypersonic facilities that encompass a significant range of rarefaction and nonequilibrium effects. Computational studies using direct simulation Monte Carlo (DSMC) and Navier-Stokes solvers have been applied to selected experiments performed in each of the facilities. In addition, computations have been made for typical flight conditions in both Earth and Mars atmospheres, hence more energetic flows than produced in the ground-based tests. Also, comparisons of DSMC calculations and forebody measurements made for the Japanese Orbital Reentry Experiment (OREX) vehicle (a 50 deg spherically-blunted cone) are presented to bridge the spectrum of ground to flight conditions.