Mechanism and influencing factors analysis of windage losses from aeronautic spiral bevel gear

Based on the computational fluid dynamics （CFD） theory，the airflow characteristic and the mechanism of gear windage losses around the single spiral bevel gear were simulated and analyzed using shear stress transfer （SST） k-ω turbulence model and multi-reference rotation model （MRF） technology and the Coupled decoupling algorithm.The influence of gear speed，rotation direction and shroud configuration on windage power loss was researched.Then the windage moment was studied by orthogonal experiment and numerical simulation analysis with the difference clearance value between the shroud and the tooth surface，the heel and toe of the gear.By means of variance analysis and data fitting，the functional relationship between the windage losses and the clearance value of the gear was obtained.The results showed that when the shroud clearance value was 1mm，the windage moment was the smallest，and the effect of reducing the windage power loss was the best.The optimal reference value of the clearance between the shroud and the gear was given by using the single-objective optimization analysis method，which provided the theoretical basis and research method for further studying the multi-objective optimization of the shroud clearance and also a reference for the engineering application of the windshield.