Zhang et al (2006) utilized CFD to examine the validity of erosion models that have been implemented into CFD codes to predict solid particle erosion in air and water for Inconel 625. This work is an extension of Zhang’s work and is presented as a step toward obtaining a better understanding of the effects of fluid viscosity and sand particle size on measured and calculated erosion rates. The erosion rates of Aluminum 6061-T6 were measured for direct impingement conditions of a submerged jet. Fluid viscosities of 1, 10, 25, and 50 cP and sand particle sizes of 20, 150, and 300 μm were tested. The average fluid speed of the jet was maintained at 10 m/s. Erosion data show that erosion rates for the 20 and 150 μm particles are reduced as the viscosity is increased, while surprisingly the erosion rates for the 300 μm particles do not seem to change much for the higher viscosities. For all viscosities considered, larger particles produced higher erosion rates, for the same mass of sand, than smaller particles. Concurrently, an erosion equation has been generated based on erosion testing of the same material in air. The new erosion model has been compared to available models and has been implemented into a commercially available CFD code to predict erosion rates for a variety of flow conditions, flow geometries, and particle sizes. Since particle speed and impact angle greatly influence erosion rates of the material, calculated particle speeds were compared with measurements. Comparisons reveal that, as the particles penetrate the near wall shear layer, particles in the higher viscosity liquids tend to slow down more rapidly than particles in the lower viscosity liquids. In addition, CFD predictions and particle speed measurements are used to explain why the erosion data for larger particles is less sensitive to the increased viscosities.
Importance of Considering Interstitial Fluid Effects in the Kinetic Theory of Granular Flow for Raceway Formation Prediction
