Experimental and numerical study of stator end-winding cooling with impinging oil jet. (5th February 2023)

• Record Type: Journal Article
• Authors: Chen, Pin; Ben Hassine, Nidhal; Ouenzerfi, Safouene; Harmand, Souad
• Is Part Of: Applied thermal engineering. Volume 220(2022)
• Publication Date: 2023-02-05
• Subjects: Electric machine -- Impinging jet -- Infrared imaging -- Inverse method -- Heat dissipation -- Heat transfer coefficient; Heat engineering -- Periodicals; Heating -- Equipment and supplies -- Periodicals; Periodicals; 621.40205
• DOI: 10.1016/j.applthermaleng.2022.119702
• Languages: English
• ISSNs: 1359-4311

Abstract

Graphical abstract: Highlights: Internal flow configuration with more contact surface enhances cooling effect. External flow configuration achieves more homogenous cooling performance. Heat transfer coefficient increases with higher heating power or flow rate. Heat transfer improvement is significant when flow rate changes from 0 to 0.35 kg/min. Abstract: As an efficient cooling technology, impinging jet was utilized to reduce end-winding temperature of electric machine stator in this study. Infrared imaging and numerical simulation technologies were applied to investigate heat dissipation efficiency of silicone oil jet on a real electric machine stator. Infrared camera is possible to measure end-winding temperature without influence on flow pattern and heat exchange. Numerical simulation results for end-winding temperature were validated by comparing to experimental results. Then heat transfer coefficient was calculated by inverse method, which is very difficult to be obtained by experimental method. The testing stator had three configurations, among which one was covered by aluminum foil at external surface and the other one had extra internal surface in order to lead oil flow to contact all the end-windings. Moreover, effect of dissipated heat quantity and oil flow rate were considered in present study. According to experimental and simulation results, the configuration with internal surface reveals best cooling performance by impinging oil jet. For this stator configuration, the minimum and the most cost-effective oil flow rates were found which will provide insight for impinging jet system.