The Design Optimization Of Axial Flow Fan And Its Effect On The Cooling Performance Of The Motor

Axial flow fan occupies an important role in many industrial applications and its primary objective is to provide a large volume of airflow parallel or corresponding to the axis of rotation for heat and mass transfer operations and it is widely used in various industrial equipment and processes.All the major industries such as textile mills,fertilizer industries,chemical and pharmaceuticals,power generation etc.use different capacity axial flow fan for different purposes.However,the benefit of using axial flow fan for the purpose of augmenting heat transfer is particularly evident in those industries where large capacity motors are extensively used.In this research,the computational fluid dynamics(CFD)modeling of the axial flow fan of the air-cooled motor is presented.The computational domain is established on the main stream designing software SOLIDWORKS and consists of fan blades,fan box,fan shaft,shrouds,hub and spin-wall.The mesh has been generated on the GAMBIT.The numerical simulations are performed to investigate the impact of installation angle,pressure variations and the number of blades on the functioning/performance of the axial flow fan using ANSYS Fluent 16.0.Moreover,the effect of turbulence models and blade trimming on the volumetric flow rate is also studied.A study on the variation of turbulence intensity to find the best possible position of the fan so that it can cool the motor in an efficient way is also carried out.To ensure the accuracy of the results,the comparison of volumetric flow rates of complete model and simplified model is carried out.Finite volume method has been employed and three-dimensional turbulent flow equations are solved numerically.The results show that the volumetric flow rate decreases as the outlet pressure increases.The values of volumetric flow rate and efficiency of the axial flow fan are higher when the angle of installation increases and finally is highest at 30° and blades of the fan are 19.The results of standard SST k-? model and standard k-? model are almost similar;however,the calculation accuracy of SST k-? model is slightly better than that of standard k-? model.There is a significant decline in the values of volumetric flow rate when trimming of the blade width is made.An analysis on the turbulence intensity shows that the value of turbulent intensity at the outlet setting has little effect on the calculation results.There occurs a difference of approximately 0.06% on the all internal monitoring surfaces when the turbulent intensity at the outlet is increased to 5%.This research could provide an insightful understanding of the design optimization of axial flow fan and be helpful in designing a fan to improve the overall cooling performance of the systems.