Measured Particle Rebound Characteristics Useful for Erosion Prediction

Abstract

Extensive high temperature particle rebound testing has been continuing at the Professor University of Cincinnati for the past three years utilizing the new high temperature material erosion facility. Particle rebound characteristics including particle angle Department of Aerospace Engineering and and velocity restitution ratios are important in the prediction of particle trajectories Applied Mechanics, University of Cincinnati, through a turbomachine or other flow devices where particulate erosion is presentCincinnati, OH and the prediction of erosion patterns is desired. This paper presents particle rebound data which has been accumulated for 160 microns particles impinging on INCO 718, Ti 6-4 and 2024 AL targets. Particle rebound characteristics are compared with important parameters such as target temperature, particle impingement velocity and particle impingement angle. In addition a semi-empirical erosion rate equation for INCO 718 material is derived.

3-D LDV measurements of particle rebound characteristics

“…One should also remember that, due to symmetry only about half the particles rebound in a given direction (+y), while the other half rebound in the opposite direction from the xz plane (-y). The following least squares polynomial curve fit expressions were obtained for the 3-D tangential restitution ratios: It should be noted that, the expressions given in equations (4) through (13) are valid for impact angles up to 75 degrees. They do not apply at PI = 0 degree, since a physical impact does not occur at this angle, and e~ becomes mathematically undefined.…”

Assessment of Scavenge Efficiency for a Helicopter Particle Separation System

“…Considerable research in this area was conducted by Wakeman and Tabakoff (Ref. 13). Based on their experiments with 165-μm silica particles impinging on 2025 AL, INCO 718, and Ti 6-4 target walls, a few semiempirical expressions of restitution coefficients were derived.…”

Particle Distribution and Erosion During the Flow of Newtonian and Non-Newtonian Slurries in Straight and Coiled Pipes

“…The determination of particle trajectories in erosion modeling is based on particle rebound characteristics and restitution coefficients. Wakeman and Tabakoff (1982) have defined the restitution ratio as the ratio between the particle relative velocities after and before collision with the target material. Wakeman and Tabakoff (1982) and Forder, Thew and Harrison (1998) have reported experimentally determined rebound data and restitution coefficients for different target materials.…”

“…Wakeman and Tabakoff (1982) have defined the restitution ratio as the ratio between the particle relative velocities after and before collision with the target material. Wakeman and Tabakoff (1982) and Forder, Thew and Harrison (1998) have reported experimentally determined rebound data and restitution coefficients for different target materials. Nevertheless, the literature lacks the empirical data for particle flow and rebound characteristics in slurries with viscous Newtonian and non-Newtonian base fluids.…”