Abstract
The paper presents a comprehensive methodology for simulating transient flow in pipeline systems induced by valve closure, using the method of characteristics with an unsteady friction model. The research focuses on the instantaneous acceleration-based (IAB) model, a mathematical model employed to describe water hammer behavior in pipeline systems. The methodology includes the development of a mathematical model based on governing fluid dynamics equations, numerical simulation using the proposed model, and validation against experimental data obtained from laboratory-scale pipelines. The study compares the performance of steady and unsteady friction models, revealing the limitations and strengths of each in simulating water hammer events. The paper also discusses the estimation of the damping coefficient (k) using trial-and-error and Reddy's analytical method, and the influence of numerical parameters on the IAB model performance. The numerical results demonstrate good agreement with experimental data, validating the proposed model's accuracy. The methodology presented in this paper can serve as a valuable tool for analyzing and designing pipeline systems subject to water hammer phenomena. It provides insights into transient flow characteristics induced by valve closure and assists in identifying appropriate mitigation measures to prevent damage to the pipeline system.
