Influence of tip clearance on the turbulent aerodynamics of axial flow fan under off design conditions

Compressor is a dynamic machine with complicated 3d aerodynamics. Dynamics creates an uncertain environment and induces the flow with instabilities, resulting in reduced performance. Motion being circumferential, flow is also subjected to rotational accelerations. Added to these complications are the tip gap and related vortex aerodynamics in the tip region, which also influence the passage flow of the rotor and thus complicates the flow field. The result of these implications is the generation of the turbulence in the flow field. Turbulence is a fluctuating characteristic of the flow, which extracts its energy from the mean flow field. Energy consumed by the turbulent nature of flow is a waste. Therefore it is very much important to understand about the influence of the turbulence and related kinetic energy compressor aerodynamics. In this paper work is presented to understand about the turbulence under such varying geometry conditions of flow, as well as blade. Results of nature of the turbulence and its growth are discussed for varying mass flow rates and different tip gaps of acceptable range.