Cooling Holes in Polymer Spur Gears: A Critical Analysis of Heat Dissipation Benefits and Mesh Stiffness Penalties

ABSTRACT Polymer spur gears offer advantages such as low weight and reduced noise but are often limited by heat accumulation during operation. This study investigates cooling holes as a passive thermal‐management strategy and quantifies the resulting thermal–mechanical trade‐off in polyoxymethylene (POM) spur gears. Three‐dimensional finite element analysis (FEA) coupled with response surface methodology was used to evaluate cooling‐hole diameters ranging from 0.5 to 1.5 mm ( D/m = 0.25–0.75) and locations from 3 to 4 mm ( L/m = 1.5–2) below the tooth tip. The results show that cooling holes reduce maximum operating temperature by up to 9.39% while decreasing mean gear mesh stiffness (GMS) by 0.84%–15.62%. Hole diameter is identified as the dominant parameter governing both cooling effectiveness and stiffness degradation, whereas hole position exerts a secondary influence. A validated quadratic regression model ( R 2 = 0.932), calibrated using a face‐centered central composite design and independently verified with four hold‐out configurations, enables rapid estimation of GMS without repeated finite element simulations. The findings provide practical design guidelines for balancing thermal management and structural performance in polymer spur gears.