Optimization of Internal Rotor Cooling Using Variable Fan Configuration and Blade Angles in a Synchronous Reluctance Motor

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Published: Sep 26, 2026
Keywords:
Internal rotor cooling Fan blade angle Fan position Synchronous reluctance motor (SynRM)

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P. H. Ngo
Department of Mechanical Engineering, School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10250, Thailand
N. Depaiwa
Department of Mechanical Engineering, School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10250, Thailand
T. Pham
Department of Mechanical Engineering, School of Engineering, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10250, Thailand
C. T. Vo
Faculty of Automotive Engineering Technology, Industrial University of Ho Chi Minh City, Ho Chi Minh City, 727900, Viet Nam
M. Masomtob
National Energy and Technology Center (ENTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
B. Kerdsup
National Electronics and Computer Technology Center (NECTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand
P. Champa
National Electronics and Computer Technology Center (NECTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, 12120, Thailand

Abstract

This study investigates the cooling efficiency of an internal rotor fan system integrated into a synchronous reluctance motor (SynRM), aiming to optimize key fan configuration parameters. The analysis focuses on the effects of fan blade angle, installation position (front, back, and both), and rotational speed on the motor’s thermal behaviour under various operating conditions. The experiment evaluated the cooling efficiency, while the simulation model was used to clarify the effects of air velocity and pressure on cooling performance. The results show that fan blade geometry and positioning influence the heat transfer coefficient. The 60o fan blade configuration, when installed at the rear side, generates the highest cooling airflow through the rotor, reaching 11.31 m³/h at 2000 rpm, it achieves the lowest rotor temperature of 43°C after 10 minutes of cooling. Moreover, increasing the fan’s rotational speed from 1000 rpm to 3000 rpm enhances airflow, which improves heat transfer and further lowers rotor temperature. These findings contribute to improved thermal management strategies in SynRM design by demonstrating how integrated fan systems can enhance cooling efficiency through optimized configuration.

Article Details

How to Cite
Ngo, H. P., Depaiwa, N., Pham, T., Vo, C., Masomtob, M., Kerdsup, B., & Champa, P. (2026). Optimization of Internal Rotor Cooling Using Variable Fan Configuration and Blade Angles in a Synchronous Reluctance Motor. Journal of Research and Applications in Mechanical Engineering, 14(3), JRAME–26. retrieved from https://ph01.tci-thaijo.org/index.php/jrame/article/view/264535
Issue
Vol. 14 No. 3 (2026)
Section
RESEARCH ARTICLES
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