Date of Award


Publication Type


Degree Name



Mechanical, Automotive, and Materials Engineering




Induction motors, Hollow shaft, Counterflow design, Heat transfer, Liquid convection



Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.


This thesis investigates methods of implanting a forced liquid convection heat recovery system within an induction motor’s shaft to cool the rotor.

The objective is to design a hollow shaft that can meet the target goals of keeping the components under an average temperature of 100℃ under different motor power conditions. Three hollow shaft design cases were studied at steady state conditions to evaluate their heat transfer performance and surface temperature to meet the goals of the study. This includes the design of a counterflow, counterflow with fins, and duct design.

It is found that third design is able to improve the temperature of the shaft while being manufacturable in a simple manner for future mass production. The heat transfer coefficient is also increased by 303% compared to a counterflow design. The duct design was further evaluated at different motor power conditions:

1. Continuous conditions at rated speed

2. Continuous conditions at max speed

3. Peak conditions at rated speed

4. Peak conditions at max speed

This design is able to meet the target goal of keeping the surface less than an average temperature of 100℃ for three of the four conditions.