Numerical Simulations of Particle Transport and Deposition Experiments at Gas Turbine Temperatures

Abstract

The ingestion of micron-sized particulates into gas turbine engines is known to cause a number of damage mechanisms, from in-flight engine to component life-reduction. Numerical simulations are presented of particle deposition experiments at temperatures representative of gas turbine secondary air systems. The continuous random walk (CRW) model is applied to simulate the fluid turbulent fluctuations observed by the particle in a steady simulation. The CRW model assessed for the first time under an external body force, namely gravitational conditions perpendicular to the bulk flow. The introduction of the external body force is seen to require a redevelopment of the numerical integration time step. This captures the crossing trajectories effect. At ambient isothermal conditions, simulation-experimental differences were seen to be 0.9-49.7%; at high temperature isothermal conditions the differences were seen to be 12.6-50.1%. Simulations of non-isothermal flows were able to capture thermophoretic effects well through the use of the Beresnev and Chernyak thermophoretic coefficient, rather than the widely-used Talbot coefficient.