Depth-averaged vs. Full 3-D SPH Models: A Comparison of Accuracy and Computational Speed for Simulating Dam Break Flash Flood

Civil Engineering Department, Faculty of Engineering, Bina Nusantara University, Jakarta, Indonesia 11480

^* Corresponding author: muhammad.hafiz004@binus.ac.id

Abstract

Dam-break flow is a three-dimensional (3-D) phenomenon that is often numerically modeled using depth-averaged formulation, omitting the 3-D effect for computational efficiency. This study compares the performance and accuracy of depth-averaged and 3-D models, particularly using Smoothed Particles Hydrodynamics (SPH) method. Both models accurately predict flow evolution, with the 3-D model capturing detailed 3-D effects. However, the depth-averaged model shows significantly shorter computation time (by 20 times) and memory usage due to fewer particles used. However, it shows slower computational effort per particle due to the time-consuming Newton-Raphson iterative procedure. This study provides insights into the performance and accuracy of two commonly used models in simulating violent fluid dynamics, aiding model selection for specific applications.