Direct Numerical Simulation of Turbulent Transport with Uniform Wall Injection and Suction

摘要

A direct numerical simulation (DNS) of the fully developed turbulent channel flow and heat transfer with uniform wall injection and suction was carried out. The Reynolds number, which was based on the channel half-width and the friction velocity averaged on the two walls, was set to be ISO, whereas the Prandtl number was 0.71. The walls were assumed to be kept at isothermal but different temperatures. With any buoyancy effect neglected, temperature was considered as a passive scalar. The computation was executed on sufficiently dense grid points by using a spectral method. The statistics obtained include the mean velocity and temperature, Reynolds stresses, and turbulent heat fluxes. Each term in the budget equations of the second-order velocity and temperature correlations and of their destruction rates was also calculated. It is found that the injection decreases the friction coefficient, but tends to stimulate the near-wall turbulence activity so that the Reynolds stresses and turbulent heat fluxes are increased, whereas the suction has an inverse influence.