On the question of computing convective heat transfer parameters in a laminar-to-turbulent boundary layer on an impermeable hemispherical surface

Abstract

In order to qualitatively solve the problem of computing convective heat transfer parameters in a laminar-to-turbulent boundary layer, it is necessary to numerically integrate differential equations descrybing that layer, completed by semiempirical turbulent viscosity models. These must be validated using results of experimental investigations where the gas dynamics of a gas flow around a body is correctly simulated. In terms of practical applications, developing relatively simple yet highly accurate computation methods is important. At present, the most widely used method to solve this type of problems in aviation and aerospace engineering is the effective length method developed by V.S. Avduevskiy, Academician. The paper shows that significant errors characterise computations using this method and traditional turbulent viscosity models to determine parameters of those blunted components of aircraft that are subjected to the highest temperatures. We present a solution to this problem, based on constructing systematic numerical solutions to the equations describing the laminar-to-turbulent boundary layer and subsequently approximating them. We prove that this approach ensures both acceptable computation accuracy and solution simplicity.