Investigation of Mechanical Erosion in Fuel Pipelines

The aim of this work is to investigate the characteristics of mechanical erosion in a vertical sudden expansion turbulent two-phase flow. The flow field in an axisymmetric sudden expansion flow laden with round glass particles at 3% per volume and flowing in the direction of gravity was examined both experimentally and computationally. Velocities of particles and fluid were simultaneously measured at Re = 6 x 104 using a single component laser Doppler anemometer and a burst peak detector which discriminates the amplitude of the Doppler bursts resulting from the two discrete phases. The test facility was refractive index matched, allowing measurement of the bar-U, V, bar-u2, v2 and w2 components throughout the whole velocity flow field. Computations were performed using a Eulerian/Langrangian approach considering drag, lift and gravity forces acting on a particle as well as modelling of particle-dispersion by turbulence, particle-wall and particle-particle collisions. Mechanical erosion of the pipe wall was determined via an empirical formula, using the predicted impact velocities and angles.