Swirl flow has applications in many of the engineering equipments. Good amount of calculations exist which have been developed for design of propellers. However, swirler design for combustion applications is different from that for propeller applications. In the former swirl flow is generated by the application of tangential component to the axial flow whereas in the latter swirl is generated by the rotating propellers. Therefore it comes under the category of rotating flows. Quite a few studies have been carried out on vane generated swirl flows over the past four decades. Majority of the studies were based on experiments. Over the last one decade, attention has been focused on the numerical predictions. Due to the advent of fast digital computers, nowadays the CFD studies are becoming the part of the design methodologies. This study mainly focuses attention on arriving at best vane angle from aerodynamic aspects for the combustion applications. As there are large number of flow and geometric parameters involved arriving at the best design by experimental methods is rather difficult compared to CFD analyses. The important geometric parameters are vane angle, vane numbers and hub to tip ratio. The flow parameter involves the selection of appropriate turbulence model for the prediction. The uniqueness of this study is in arriving at the best vane angle using appropriate turbulence models for both weak and strong swirl. To this end experimental and numerical studies have been carried out. It is found that no single turbulence model is able to handle both weak and strong swirl. From this study it is concluded that for weak swirl standard k - ε model is sufficient whereas for strong swirl one has to resort to Reynolds stress model. The characteristics of swirl flow are evaluated by means of size of the recirculation zone, mass trapped in the recirculation zone and also the pressure drop. Over the range of vane angle investigated the best vane angle is found to be 45°. © 2007 Elsevier Masson SAS. All rights reserved.