NUMERICAL STUDY OF THE INTERACTION BETWEEN A SUPERSONIC JET AND PLANAR SURFACE / ESTUDO NUMÉRICO DA INTERAÇÃO ENTRE UM JATO SUPERSÔNICO E UMA SUPERFÍCIE PLANA
AUTOR(ES)
MARIA ANGELICA ACOSTA PEREZ
DATA DE PUBLICAÇÃO
2008
RESUMO
I in this work a study of the interaction between a supersonic jet and a planar surface is presented, with the aim to analyze the behavior of the velocity, pressure and temperature flowfield. This study finds its motivation in the process of thermal spallation of hard rocks, which may result from the interaction between a high pressure and high temperature jet and the rock. This process, that can be used in the drilling of hard and deep rocks, occurs due to the accumulation of thermal stresses in the rock, which can cause its fracture. This type of process also involves several aerodynamic and thermodynamic mechanisms, which are still open phenomena. In the development of this work the flow was modeled by the two-dimensional Navier-Stokes equation for a mixture of perfect gases in a cylindrical coordinates system. The model considered to describe the turbulent transport is the one equation of Spalart - Allmaras model, which involves the solution of a differential equation for the turbulent viscosity. These equations are solved using a finite volumes methodology which is adapted to compressible flows. The description of the obtained transient flow required several modifications in the existing computational code. These modifications involved, in particular, the choice of boundary conditions, that use the notion of characteristics, and the turbulence model. The structure of the flow resulting from the interaction between the supersonic jet and the wall is studied. In particular, are examined the influence (i) the distance between the jet and wall, (II) of the pressures ratio between the jet and the environment. Moreover, the transient evolution of the flow is examined. The obtained results are examined to determine the best aerodynamic conditions for the process of thermal spallation to occur.
ASSUNTO(S)
metodos numericos compressible flow volumes finitos finite volume escoamento compressiveis numerical methods
