Current Volume 9
Optimization of Hollow Shaft Geometry for Rotor Cooling in Inductions Motors Using Response Surface Methodology
Abstract
Maintaining performance and dependability in induction motors requires efficient thermal management, especially as power density requirements rise in electric vehicle applications. Although direct rotor heat extraction is possible with hollow shaft cooling, systematic geometric optimisation that takes structural, hydraulic, and thermal trade-offs into account has not yet been investigated. This study optimizes hollow shaft geometry for a 120-kW induction motor using Response Surface Methodology (RSM) coupled with Computational Fluid Dynamics (CFD). Three variables were examined in relation to four responses: heat transfer coefficient, temperature reduction, pressure drop, and structural safety factor. These variables were fin density (15–25 fins/100 mm), channel aspect ratio (1.5–2.5), and coolant flow rate (4–8 L/min). A Central Composite Design with 20 experimental runs was employed. Coolant flow rate emerged as the dominant factor influencing all responses. Maximum thermal performance (709.6 W/m²·K, 18.07°C reduction) occurred at the highest factor levels but produced the lowest safety factor (1.753) and the highest pressure drop (22.98 kPa), confirming inherent design trade-offs. Linear models adequately predicted thermal responses, while pressure drop and safety factor exhibited significant curvature, requiring quadratic modeling. The optimized configuration balances thermal enhancement against hydraulic and structural constraints, providing a validated framework for hollow shaft cooling design in traction motors.
Keywords
Induction Motor, Hollow Shaft Cooling, Response Surface Methodology, Thermal Management, Multi-Objective Optimization, Rotor Cooling
Citations
IRE Journals:
Onyeji Levi Chinaka, Ibezim Joseph Maduabuchi, Dr Samuel O. Ikegbula, Unya Ndukwe "Optimization of Hollow Shaft Geometry for Rotor Cooling in Inductions Motors Using Response Surface Methodology" Iconic Research And Engineering Journals Volume 9 Issue 12 2026 Page 1416-1434 https://doi.org/10.64388/IREV9I12-1718796
IEEE:
Onyeji Levi Chinaka, Ibezim Joseph Maduabuchi, Dr Samuel O. Ikegbula, Unya Ndukwe
"Optimization of Hollow Shaft Geometry for Rotor Cooling in Inductions Motors Using Response Surface Methodology" Iconic Research And Engineering Journals, 9(12) https://doi.org/10.64388/IREV9I12-1718796
About IRE Journals
IRE Journals is an open access online journals established with an aim to publish high quality of research work in various diciplines. We have more than 6 years in publications. Over 2500+ papers already published.
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