Effect of software implementation on the result of computational fluid dynamics simulation of circulating fluidized bed risers

Abstract

Abstract While in scientific literature much focus is directed toward model validation, comparison, and even parametric investigations on individual model parameters, the possible effects of the used computational fluid dynamics (CFD) software on the results are largely neglected. In this article, CFD modeling of circulating fluidized beds (CFB) are performed with Ansys Fluent and OpenFOAM to investigate the effect of software implementation on the simulation results. Transient Eulerian–Eulerian simulations are performed of two different laboratory‐scale CFB cold models in turbulent and circulating fluidized bed conditions. The same mesh and as identical models and settings as possible are utilized on both software. The obtained time‐average profiles of pressure, velocity, and solids volume fraction are compared between the software and with available measurements. A difference in the granular energy equation was identified between the software, and a modification was made to achieve the same formulation. The effect of boundary conditions was also investigated. It was found that depending on the case, the software could have a notable effect on the results. These differences are found especially in particle distribution, visible in the vertical pressure and solids volume fraction profiles as well as in external circulation mass flow rates.

Keywords

• CFB
• CFD
• software implementation