Modelling of the pressure-velocity correlation in turbulence diffusion (Q686887)

Most current computations of turbulent flows adopt diffusion models which neglect the effect of the pressure-velocity correlation in the diffusion process. In the present paper the importance of this correlation effect is elucidated, the neglect of this effect constitutes some of the major defects in the application of the second-moment closures. Through the relation between \(\overline{pu_ i}\) and \(\overline{u_ i u_ p u_ p}\), we propose here a new type of turbulence diffusion model which takes into account the pressure effect. Application of this new model in the computation of the turbulence shearless mixing layer and plane- and round-jet flows shows that the spreading rates of these flows can be captured satisfactorily. The well-known ``anomaly'' in jet-flow predictions is now corrected satisfactorily.