Influence of Shaft Offset, Rotational Speed, Spiral Angle and Torque on Efficiency and Power Losses in Automotive Hypoid Gear Train using Simulation Tool

Year 2025, Volume: 9 Issue: 3, 374 - 381, 30.09.2025

Dr. Shıvakumar Nagareddy , Ravi Subramanyam , Vijay Govindarasu

https://doi.org/10.30939/ijastech..1673182

Abstract

The complex geometry with sliding contact surfaces of hypoid gear pair with differential unit in automotive vehicles results in increased frictional losses and reduced mechanical efficiency. This study focuses on the influence of shaft offset, spiral angle of hypoid gears, shaft rotational speed of shaft and torque transmitted on the efficiency and power losses of hypoid gears with differential units used in automotive vehicles. AMESim simulation tool was used to optimize the key parameters towards maximum efficiency, and lower power losses through bearings as well as gear pair. The geometry of hypoid gear train with differential unit including forces (ra-dial, axial and tangential) consideration was modeled and tested for gear efficiency and power losses at various values of shaft offset, spiral angle, shaft rotational speed and torque. From the simulation results, it is observed that the maximum increment in total power loss achieved from 10 mm to 25mm shaft offset was 81%. The global efficiency of the gear system showed maximum when the shaft offset was small and the spiral angle was small. The maximum efficiency drop from 40° to 50° spiral angle was about 51% and the total efficiency drop from 30° to 50° spiral angle was 81%. The global efficiency of the gear system was increased gradually with the increase of rotational speed. The maximum percentage increase in total power losses from 1000 rpm to 2000 rpm speed was 102.6%. The significant power losses and maximum increase in ef-ficiency happen between 200 Nm to 300 Nm and its total power loss increase was 51%. This study serves as a valuable resource for gear manufacturers to improve the efficiency of the hypoid gear train with differential units through optimizing the input key parameters with reduced power losses.

Keywords

Differential unit , Gear efficiency , Hypoid gear , Shaft offset , Spiral angle

Ethical Statement

Authors declare that the submitted research article is original one and is not submitted to any other journals or elsewhere.

Supporting Institution

Chennai Institute of Technology, Chennai, India.

Thanks

We thank the management of the supporting institute for providing the facility available in the campus to conduct this research study.

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