Abstract—The experimental investigation of flow analysis in a diffuser using protrusion and vortex generators is carried out. Two diffuser angles are looked into. One pair protrusion and one and two vortex generator pairs are considered. The velocity profile at the diffuser inlet is uniform and the flow is a developing one. The protrusion and vortex generators are placed near the diffuser inlet. The Reynolds number based on the diffuser length is in the range 2.3-3.6 × 10⁵. It is seen that the pressure coefficient is lower for the rough case, compared to the smooth one. It increases with the diffuser angle, as the pressure rise is higher. It also increases with Re. The skin friction coefficient decreases with Re. The smooth case has a lower value. It is higher for the case with a higher diffuser angle. The parallel configuration of protrusion yields the maximum value. It also decreases with the protrusion angle.

Index Terms—Skin friction coefficient, Pressure coefficient, Diffuser, Protrusions, Vortex generator

Cite: Ghobad Shafiei Sabet, S Pavithran, and R R Kulkarni, " The Effect of Vortex Generators on Pressure and Skin Friction in a Diffuser," International Journal of Mechanical Engineering and Robotics Research, Vol. 2, No. 4, pp. 291-301, October 2013.