          Numerical Calculations Of Erosion In An Abrupt Pipe Contraction Of Different Contraction Ratios Habib, MA; Badr, HM; Ben-Mansour, R; Said, SAM JOHN WILEY SONS LTD, INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS; pp: 19-35; Vol: 46 King Fahd University of Petroleum & Minerals http://www.kfupm.edu.sa Summary Erosion predictions in a pipe with abrupt contraction of different contraction ratios for the special case of two-phase (liquid and solid) turbulent flow with low particle concentration are presented. A mathematical model based on the time-averaged governing equations of 2-D axi-symmetric turbulent flow is used for the calculations of the fluid velocity field (continuous phase). The particle-tracking model of the solid particles is based on the solution of the governing equation of each particle motion taking into consideration the effect of particle rebound behaviour. Models of erosion were used to predict the erosion rate in mg/g. The effect of Reynolds number and flow direction with respect to the gravity was investigated for three contraction geometries considering water flow in a carbon steel pipe. The results show that the influence of the contraction ratio on local erosion is very significant. However, this influence becomes insignificant when the average erosion rates over the sudden contraction area are considered. The results also indicate the significant influence of inlet velocity variations. The influence of buoyancy is significant for the cases of low velocity of the continuous flow. A threshold velocity below which erosion may be neglected was indicated. Copyright (C) 2004 John Wiley Sons, Ltd. References: 1. AHLERT KR, 1994, THESIS U TULSA US 2. BENCHAITA MT, 1983, J ENG IND-T ASME, V105, P215 3. BOULET P, 1999, P 1999 ASME FLUIDS E