Design Optimization Of Axial Fan Of The Air Conditioner Outdoor Set

With the competition in the air conditioning industry becoming increasingly fierce,The requirements of performance and noise reduction for the air conditioner manufacturers are increasing gradually.As a provider of air volume for heat transfer in air conditioner outdoor set,the efficiency of axial fan affects the performance of the air conditioner outdoor set.Therefore,through the optimization design and the simulation of the internal flow distribution of the outdoor axial flow fan,we improved the internal flow in the air conditioner outdoor set,this work has important significance for the performance of air conditioner outdoor set.In this thesis,the CFD numerical simulation method is used to optimize the design of the outdoor axial flow fan for the air conditioner outdoor set:(1)Trailing edge gap design on the axial flow fan,by analysis of different location and size of the trailing edge gap design on the outdoor performance and the influence of flow field,find out it's influence on the flow distribution.(2)Tip bending design in the axial flow fan blade,by analysis of different bending angle of the blade tip bend effect on the performance and the flow distribution in the air conditioner outdoor set,find out the best tip bending Angle.(3)Modification of axial flow fan sweep angle,analyzes its influence on the performance of the outdoor machine,re configuration of axial flow fan with forward swept angle.(4)According to previous research,a comparison of performance and surface sound pressure level changes between the new optimized axial flow fan and the original model.According to the research results:it is found that with the increase of the radius of the trailing edge gap and the continuous movement of the position,the total pressure of the fan is reduced,which results in the decrease of the the air conditioner outdoor set performance.At the same time,the gap of the trailing edge can weaken the performance of the fan,and can reduce the weight of the fan and the load of the motor;The aerodynamic performance and the full pressure efficiency of the outdoor fan are effectively improved after the blade tip bending treatment.When bending angle of 1.5 degrees is the best bending angle.At this time in the same amount of air flow,the axial flow fan full pressure can be increased by 6%,the total pressure efficiency can be increased by about 1.5%;the axial flow fan wheel For air conditioner outdoor set,the sweep forward did not in the best position,appropriate to enhance sweep forward can obtain higher performance.After the optimization of the original model,at the same outdoor machine demand air pressure,the efficiency of the the axial flow fan improved 4%.The surface sound pressure level in the leading edge of the blade trailing edge tip and the trailing edge of the corresponding guide ring position has been reduced.