Bends are primary source of formation of secondary flow and swirling vortices in pipes, channels and ducts. Flow losses and heat transfer are strongly affected by presence of bends in the flow passage therefore, in depth characterization of flow through bends is required. In the current study, the three dimensional, turbulent and incompressible flow through 90-degree bend is examined by using a CFD package Star CCM+. The data is analyzed in the results section to evaluate the effect of changing bend curvature ratio (λ=RC/d) and shape of cross section on intensity of secondary flow. It is observed that swirl intensity reduces drastically as curvature ratio is increased. Twin secondary vortices are formed and their intensity is a function of pressure gradient in the curved region of bend. Furthermore, it is found that circular cross section better supports the formation of dean vortices and secondary flow as compared to square and rectangular cross sections. The intensity of swirling vortices is also found decreasing as the aspect ratio of the rectangular section is increased up to 3:1. It means that there are lower flow losses for rectangular cross section bends with high aspect ratios as compared to square and circular cross section bends.