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Abstract: Large Eddy Simulations (LESs) were performed for a confined rectangular liquid jet with a co-flow and compared in detail with particle image velocimetry (PIV) measurements. A finite-volume CFD library, OpenFOAM, was used to discretize and solve the filtered Navier–Stokes equation. The effects of grid resolution, numerical schemes and subgrid models on the LES results were investigated. The second and fourth order schemes gave similar performance, while the fourth order scheme costs much more computationally. Subgrid model comparison showed that the locally dynamic procedure is necessary for complex flow simulation. Model validation was performed by comparing LES data for the point-wise velocity statistics such as the mean and the root-mean-square velocity, shear stress, correlation coefficient, velocity skewness and flatness with the PIV data. In addition, LES data for the two-point spatial correlations of velocity fluctuations that provide structural information were computed and compared with PIV data. Good agreement was observed leading to the conclusion that the LES velocity field accurately captures the important characteristics of all the turbulent length scales present in the flow, from the fully resolved energy-containing eddies to the subgrid-scale dissipative eddies. [Copyright &y& Elsevier]

In this work, a detailed comparison of velocity fields obtained from Particle Image Velocimetry (PIV) experimental measurement and Particle-Resolved Direct Numerical Simulation (PR-DNS) of flow inside a square duct around a train of five spherical particles at a Reynolds number of 100 based on the particle diameter D p for two different particle separation distances of l/D p ( l is the center to center distance between two neighboring particles) of 1.38 and 2.19 was performed. The PR-DNS numerical results were validated with PIV experimental data. It is argued that validations using point-wise flow measurement (such as drag on particle) are potentially unreliable for simulation verification and hence, field comparisons are needed. In addition, conclusions are drawn about the interaction of flow with spherical particles in the arrangement depending on the distance over diameter ratio and drag coefficient on the spheres were calculated. [ABSTRACT FROM AUTHOR]