November 25, 2024
Mohammad Vaghefi

Mohammad Vaghefi

Academic Rank: Associate professor
Address:
Degree: Ph.D in Hydraulic Structures
Phone: 077-31342401
Faculty: Faculty of Engineering

Research

Title
Numerical investigation of the erosion reduction in elbows using inner rifling and ring
Type Thesis
Keywords
سايش زانويي، كاهش سايش، رينگ داخلي، خان چرخان، ديناميك سيالات محاسباتي
Researchers bahareh Nemati (Student) , Mohammad Vaghefi (Primary advisor)

Abstract

Erosion caused by solid particles is usually one of the most important causes of damage to equipment and pipelines. Many industrial processes that require fluid transfer are directly exposed to leakage or contamination problems. As a result, unnecessary costs are required for the maintenance of these equipments. This industrial concern has led many researchers to develop analytical tools that can quantify erosion. Due to this fact, to validate the CFD model, the numerical results for the standard elbow are compared with the experimental data. After that, the inner ring and rifling were added to the standard elbow, which had the same geometrical characteristics of the standard elbow (such as the diameter and radius of curvature) as well as the simulation parameters (for example, the initial velocity, density, viscosity, etc.) without any changes. In fact, the main goal of this study is to investigate the effect of these two modified geometries on the reduction of elbow erosion. In the present study, numerical modeling of erosion in elbows for gas-solid two-phase flow based on one-way coupling has been done using Eulerian-Lagrangian approach. RNG ��-�� turbulence model is used to solve the flow. For erosion modeling, Oka et al.'s model is used, and for particle-wall collision modeling, Grant and Tabakov's model is used. The results of two geometries of inner ring and rifling were compared with standard elbow and analyzed. Finally, to select the optimal geometric model, two important criteria of maximum erosion and integral of the erosion surface have been taken into consideration. The remarkable result is that adding the inner ring to the standard esbow reduces the maximum erosion and also reduces the integral of the erosion surface along the elbow wall. Among the internal rings models, the elbow with two rings has resulted in the highest amount of erosion reduction by 43%. Based on the integral criterion of the erosion surface, elbow with five internal rings