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The performance of fluid transportation model through non-circular elbow ducts with wall mass injection in predicting the velocity and pressure fields is important in Industrial applications. The present work pertains to the two-dimensional numerical analysis of the developing turbulent fluid flow with uniform mass injection through the top wall of a rectangular elbow. A numerical experimentation using control volume formulation considering standard k   turbulence model has been conducted to study different parameters like the velocity distributions, size and shape of the recirculation bubble as well as the friction factor etc. The size and strength of the recirculation bubbles generated in the bend regions are affected by the continuous entry of mass injected through the wall of the elbow. The results show that the velocity field, reattachment points, friction factor etc. are influenced by the side mass injection. The recirculation bubble has been observed to diminish in size by the injection of mass with corresponding changes in the velocity and the friction factors.

Experimental investigation of the effect of bluff bodies on the turbulent flow through an asymmetric diffuser has been carried out. The rectangular diffuser is designed and made keeping similarity to that used by Buice and Eaton, [1], having an inclination angle of 10°. Three geometrical configurations have been selected for the experimentation. (I) At first the experiment has been carried out for the validation of the present results with Buice and Eaton, [1], placing no bluff body at all. (II) Thereafter measurements have been carried out by placing a single bluff body on the horizontal floor of the diffuser to estimate the effect of the bluff body on the downstream flow. (III) Finally, two identical bluff bodies are placed on the horizontal floor of the diffuser and experimental work has been carried out in order to investigate the effect of the existence of two bluff bodies on the downstream flow through the diffuser. The present results agree well with the results of Buice and Eaton, [1], to show that the recirculation zone appears just adjacent to the inclined plane when there is no bluff body in a diffuser. Also, the detailed investigation for velocity of flow field, distribution of skin friction factor along with uncertainty analysis as well as the correlation between friction factor and Reynolds Number have been carried out in the research paper.

Turbulent fluid flow and heat transfer in an asymmetric diffuser are important in the context of the power plant engineering such as gas turbine, aircraft propulsion systems, hydraulic turbine equipment etc. In the present study, an experimental investigation on the forced convective heat transfer considering turbulent air flow in an asymmetric rectangular diffuser duct has been done. The experimental setup considered for the analysis consists of a diffuser at different bottom wall temperatures and inlet conditions. The air enters into the diffuser at a room temperature and flows steadily under turbulent conditions undergoing thermal boundary layer development within the diffuser. Efforts have been focused to determine the effects of bottom wall heating on the recirculation bubble strength, thermal boundary layer, velocity fields, temperature profiles etc. The distribution of the local average Nusselt number and skin friction factor in the whole flow fields have been critically examined to identify the significance of bottom wall heating effects on the overall heat transfer rates.