Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Numerical Simulation of Water Hammer
Submission Author:
José Gustavo Coelho , MG , Brazil
Co-Authors:
José Gustavo Coelho, André Luiz Amarante Mesquita
Presenter: José Gustavo Coelho
doi://10.26678/ABCM.COBEM2023.COB2023-0987
Abstract
Water hammer refers to pressure variations resulting from changes in flow caused by disturbances imposed on the flow of liquids in conduits, whether voluntary or involuntary. Examples of such disturbances include valve opening or closing operations, mechanical failures of protection and control devices, stoppage of hydraulic turbines, and pump shutdowns due to engine power failure. It is evident that this phenomenon can lead to significant losses across various industries, highlighting the importance of studying it to minimize costs and prevent accidents. In this research, the water hammer phenomenon is analyzed using Computational Fluid Dynamics (CFD) with ANSYS, a widely used commercial software. Both ANSYS-FLUENT and ANSYS-CFX are employed for analysis, utilizing numerical methodologies to investigate three-dimensional fluid flows. The study focuses on convergence analysis and explores the transient impacts of water hammer, examining the maximum pressure values and their temporal variations. Experimental data from the literature are used to validate the numerical results. Water is chosen as the fluid medium due to its compressible characteristics. Incompressible flow approximations yield inaccurate results for water hammer cases, necessitating the incorporation of compressibility characteristics for accurate numerical modeling. The research concludes with a detailed performance comparison of the two commercial software packages, assessing their accuracy under various conditions while considering computational costs. Both ANSYS-FLUENT and ANSYS-CFX demonstrate satisfactory results, with minimal errors compared to the experimental study. However, ANSYS-FLUENT exhibits greater computational efficiency, completing the simulations in less time.
Keywords
Computational fluid dynamics (CFD), ANSYS, water hammer
