Session: 10-05-01: Multiphase Flows

Paper Number: 94738

94738 - Numerical Study of Erosion Wear on the Disc of a Butterfly Valve With Laminar Particle-Laden Flows in a Horizontal Pipeline 

Butterfly valves are used in many processes where they mostly provide on-off control services. Many industrial processes involve fluid flows carrying particles through pipes where butterfly valves are installed. The presence of those particles produces unavoidable erosion on those valves and its study is of great importance. In this paper a numerical study of the erosion wear generated in the disc of a butterfly valve is presented. A laminar flow of water with solid particles was used. The particle-laden flow was allowed to interact following a one-way coupling. The particles felt the gravity force in the horizontal pipeline and when interacting with the pipe walls they were let to bounce right off. The gravitational effect has not been incorporated in previous studies of erosion wear in butterfly valves. To analyze how the particle-fluid interaction behavior and the gravitational force modify the erosion wear pattern, the particle Stokes number (St) and the dimensionless particle fall velocity (Sv) was varied. In a previous study of the wear on the disk in a configuration without gravity (Sv=0), the dimensionless erosion rates were found to reach their lowest values when St<1. This was due to the fact that at those Stokes numbers the fluid controls the particle motion, and it moves them away from the disk when close to it. It was also found that at St>>1 the erosion rates remain constant because the particles maintain their initial dynamics due to their higher inertia. It appears to be that the Stokes number value of one is a critical point. Similarly, in the present study, it was observed that the dimensionless particle fall velocity value of 10 appear to also be a critical point. For Sv<<10, the behavior of the impact velocity, impact angle and erosion rate were similar to the ones described of the previous study without gravity. For Sv>10, the behavior of the impact velocity, impact angle (and therefore the erosion rate) were affected by how the particles interacted with the pipe walls prior to reaching the butterfly valve disc. For very small values of St and very large values of Sv, the particles did not even reach the disc. The magnitudes of dimensionless impact velocity and dimensionless impact angle have lower values at Sv<10 and higher values at Sv>10, after the particle pipe wall bounce increased the particle velocity prior hitting the valve disc. For St~1 and Sv>10 the impact velocities and erosion rates present maximums, a consequence of the particles acquiring energy from the pipe wall bouncing effect that gravity drives.

Presenting Author: Orlando Ayala Old Dominion University

Presenting Author Biography: Dr. Ayala has professional experience in all the areas of application of Mechanical Engineering, i.e., teaching, industrial, and research. In terms of his academic experience, he has been responsible for teaching and developing graduate and undergraduate courses for a number of subjects such as Fluid Mechanics, Heat Transfer, Thermodynamics, Multiphase Flows, as well as Mechanical Engineering Laboratory courses. He has served as the academic thesis advisor for 64 undergraduate students (17 research work and 47 engineering internship work), 6 additional graduate students at the Master degree level, and over 100 undergraduate students working on their senior design projects. <br/>His research areas of interest have been multiphase flows, turbulent flows, transport of particles in fluid flows, heat transfer, numerical modeling, and high-performance parallel computing and scientific computation. He is also heavily involved in engineering education research. He has brought over $5M in mostly multidisciplinary grants to Old Dominion University. He has published more than 40 journal papers and more than 50 peer-reviewed conferences papers. He has an average citation per year of all my published work over 46.9 and I have an h-index of 19. <br/>Concurrently, he has had the opportunity to work for a number of consulting companies in Venezuela which have given him an important perspective and exposure to industry. He has been directly involved in 20 different engineering projects. In addition, he has provided service to professional organizations such as ASME. Since 2008 he has been a member of the Committee of Spanish Translation of ASME Codes and he is currently the Chair of the ASME Subcommittee on Piping and Pipelines in Spanish.

Authors:

Orlando Ayala Old Dominion University
Orlando F. Ayala Universidad de Oriente
Ricardo Villalba Universidad de Oriente