Mohamed Abd El Fatah Mohamed Teamah
numerical simulation for double diffusive mixed convection with aidingopposing flow in vertical tubes"
the present study is concerned with the mixed convection in a vertical tube under the combined buoyancy effects of thermalmass diffusion. double-diffusive convective flow in a vertical tube with upwarddownward flow is studied numerically. the flow laminarunder steady state condition are considered .the transport equations for continuity, momentum, energymass transfer are solved. the numerical procedure adopted in thisrnanalysis yields consistent performance over a wide range of parameters, richardson number, ri, (10-2 ≤ ri ≤ 10) aspect ratio, ar, 2.5 ≤ ar ≤ 20 buoyancy ratio,n,(-10<n<10(lewis number ,le,(0.1≤le≤100). the numerical results are reported for the effect of the parameters on the iso-contours of temperature,concentration. in addition, the predicted results for both localaverage nusseltsherwood numbers are presenteddiscussed for various parametric conditions. this study was done for constant grashof number, gr=105prandtl number, pr=0.71.