CFD models of jet mixing and their validation by tracer experiments

The classical theory of RTD was applied to characterize a flow in a laboratory jet mixer using both numerical and experimental approaches. Detailed information about flow field in the reactor was obtained through computational fluid dynamics (CFD) simulations. Three different turbulence models have been tested: the standard k–ɛ, RNG k–ɛ and Reynolds Stress Model (RSM). The CFD models predicted slight yet relevant differences in flow patterns. The experimental RTD can be used to identify erroneous numerical results. This paper points out differences in the predicted flow velocities. Such discrepancy may have significant impact on the assessment of the reactor's performance. Thus, the role of experimental verification is emphasized. A dedicated experiment is proposed to resolve the potential validation problem.