Effect Of Latter Rotor Parameters On The Aerodynamic Performance And Noise Of Dual-rotor Small Axial Flow Fan

Small axial flow fan as an important cooling ventilation equipment is widely used in some electronic component such as computers, projectors etc. Ventilation performance is a main factor affecting the heat dissipation of small axial flow fan. The noise as a judgement standard of the fan performance has been paid more and more attention. So it is the main studying goal that small axial flow fan is designed for big ventilation performance and small noise.Single-rotor small axial flow fan is selected as studying prototype is designed the different root fillets along blade central arced curve of the pressure side and the suction side and studied the performance of fan by numerical simulation; Based on the single-rotor small axial flow fan, dual-rotor small axial flow fan is designed and researched to acquire the aerodynamic performance and acoustic characteristics of the dual-rotor small axial flow fan by numerical simulation and experiments; Moreover, Combined with the orthogonal experiments and the entropy method, the multi-objectives optimization function used to optimize three blade structural parameters of dual-rotor small axial flow fan, which acquires the optimizing model.(1) The aerodynamic performance and acoustic characteristics of single-rotor small axial flow fans with the different root fillet at pressure side are studied by numerical simulation, and show that the local root fillet at pressure side improve the static pressure and efficiency of single-rotor small axial flow fan, the root fillet leaving blade leading edge 1/3 central arced curve enhance the ventilation performance of fan to best; the root fillet of the blade pressure side could not only improve greatly the noise generated near the root, but also have a certain degree denoise for the noise produced in the far-field.(2) The internal flow field characteristics and aerodynamic noise of single-rotor small axial flow fans with the different root fillet at suction side are studied by numerical simulation, and show that the root fillet at suction side improve greatly the noise produced near the blade root; The noise single-rotor small axial flow fans with root fillet along the whole central arced curve at suction side generated near the blade trailing edge of the root is the least and decrease up to 11.04 dB, the noise the prototype produce in far-field can be reduced up to 3.96 dB by the root fillet along the whole central arced curve at suction side.(3) The internal flow field characteristics and aerodynamic noise of dual-rotor small axial flow fans with the different latter rotor of the setting angle are studied by numerical simulation, and show that the ventilation performance and noise of dual-rotor small axial flow fans can be improved to best when the setting angle of the latter rotor is 48°.(4)thepositionandtheradiusoftherootfilletatthelatterrotorandthesettingangleofthelatterrotoronthedual-rotorsmallaxialflowfanareusedastheoptimizingfactorsoforthogonalexperiments.thestaticpressureandtheacousticcharacteristicsofthedual-rotorsmallaxialflowfanareusedastheoptimizationgoalofthemulti-objectivesoptimizationfunctiontoacquiretheoptimizingfan,theoptimizingfanandtheprototypeareresearchedbynumericalsimulation,andshowthattheoptimizingbladestructuralparametersisthatthepositionandtheradiusoftherootfilletatthelatterrotorandthesettingangleofthelatterrotoronthedual-rotorsmallaxialflowfanareleavingbladeleadingedge1/3centerarcedcurve,3mmand48°,respectively.comparedwiththeprototype,thenoisegeneratedtheoptimizingmodelcouldbereducedto4 db.theconsistencybetweennumericalsimulationresultsandexperimentalresultsinferstheoptimizationofthebladestructuralparametershasacertainreliability.