Numerical analysis of thermal dynamics and mixing performance in the blade-type static mixers

The turbulent thermal dynamics and mixing performance of kenics static mixer (KSM), lightnin static mixer (LSM) and Q-type static mixer (QSM) were numerically simulated with uniform heat flux within the range of Reynolds numbers (Re) between 6000 and 30000. The numerical predictions of Nusselt number (Nu) and friction coefficient (f) in KSM were well consistent with the experimental data. The dean vortices, thermal resistance, entropy generation and field synergy were fully analyzed to obtain the enhancement mechanism of heat transfer performance. The synergy performance between temperature gradient and flow field firstly decreased and then increased and are superior to that of KSM with increasing Re. With the same Re, the entropy generation rates of LSM are 0.93-0.94 times that of QSM. LSM is a better alternative consideration for convection mixing and heat transfer enhancement. Two new relationships between Nu and f under different dimensionless uniform heat flux are obtained.