Numerical investigation of the flow field within a curved pipe using a SEM-IDDES/SEM-IDDES-CC model

This study employed the Improved Delayed Detached Eddy Simulation (IDDES) method with the Synthetic Eddy Method (SEM) for turbulent inflow generation to conduct high-fidelity numerical simulations of complex flow within a three-dimensional U-bend pipe. The study focused on comparing simulation results against experimental measurements for axial velocity distributions, wall friction coefficients, and pressure coefficients at various axial locations. The results demonstrate that the SEM-IDDES approach accurately simulates fully developed flow within the straight sections of the U-bend pipe, capturing key flow characteristics such as the streamwise velocity profile and wall friction coefficient distribution. Furthermore, to address the strong curvature effects inherent to the bend section, a Curvature Correction (CC) model was incorporated, leading to the development of the SEM-IDDES-CC model. This enhancement aimed to evaluate the impact of curvature correction on the simulation accuracy of curved pipe flow. Comparative analysis revealed that the SEM-IDDES-CC model, incorporating curvature correction, significantly outperformed the baseline SEM-IDDES model in capturing the complex flow features within the bend region. The simulation results obtained with the SEM-IDDES-CC model exhibited markedly improved agreement with the experimental data.