The following study investigates the behavior of flow when a solid cylinder, bluff body of diameter = 0.2* inlet height of the jet is introduced at the sudden expansion channel. The expansion ratio (ER = expanded channel height/inlet height of jet) of this channel is ER = 2. The cylinder is placed at the orifice of the expanded channel, i.e. at x = 0 and y = 0. The ordinary sudden expansion with symmetric expansion exhibits pitchfork bifurcation and a cylinder in a flow exhibits an unsteady Hopf bifurcation. But introducing a cylinder will lead to the occurrence of both the bifurcation instabilities at different ranges of Reynolds number Re. Both the bifurcations are observed at different Reynolds numbers. Through this study, it is discovered that Hopf bifurcation is ceased at higher Re than the pitchfork bifurcation. Though the pitchfork bifurcation shows asymmetry in the flow at critical Reynolds number Rec, due to the introduction of the cylinder this critical Reynolds number is increased by more than 10%, hence enhancing the stability of sudden expanded channel at higher Reynolds number. Mesh dependency has also been conducted in order to recognize relevant mesh size in order to produce accurate results and also optimize computational time and cost.