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Analysis of flow field in the motor-reducer assembly with oil cooling under real driving conditions

Journal of Mechanical Science and Technology (2023)Cite this article

Abstract

The oil flow field in the motor-reducer assembly was investigated under real driving conditions to estimate the cooling performance and oil circulation. The flat, uphill, downhill, right-turn, and left-turn conditions were selected as driving conditions. First, to estimate cooling performance, the oil coverage on coil and churning phenomenon were analyzed. The downhill condition had the strongest effect of churning phenomenon, and the average temperature under this condition was 121.5 °C. Furthermore, to estimate oil circulation, oil transport between the motor and the reducer was analyzed. Under the left-turn condition, an insufficient amount of oil reached the outlet, and the flow rate of the oil pump was limited to 8.1 LPM at the oil temperature of 50 °C under the 10 LPM condition. This study provides important information about the oil flow field in the motor-reducer assembly under real driving conditions to improve cooling performance and oil circulation of EVs.

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Acknowledgments

This research was supported by the Chung-Ang University Graduate Research Scholarship in 2022. This work was supported by the National Fir Agency and the Korea Institute of Energy Technology Evaluation and Planning (KETEP) (No. 20008021). This work was supported by a Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korean government [MOTIE; grant number 20212050100010].

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Authors and Affiliations

  1. School of Mechanical Engineering, Chung-Ang University, Seoul, 06974, Korea

    Nyeongu Han, Ryanghoon Kim, Haelee Lee, Taeyoung Beom, Youngkyo Kim & Dongkyu Kim

  2. School of Computer Science and Engineering, Chung-Ang University, Seoul, 06974, Korea

    Dongkyu Kim

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  1. Nyeongu Han
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  2. Ryanghoon Kim
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  5. Youngkyo Kim
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Correspondence to Dongkyu Kim.

Additional information

Nyeongu Han obtained his B.S. and M.S. in Mechanical Engineering from Chung-Ang University, Seoul, South Korea. His research interests include thermodynamics, cooling of electric vehicle motors and lithium-ion battery.

Ryanghoon Kim obtained his B.S. and M.S. in Mechanical Engineering from Chung-Ang University, Seoul, South Korea. His research interests include thermodynamics and battery thermal runaway.

Haelee Lee obtained her B.S. and M.S. in Mechanical Engineering from Chung-Ang University, Seoul, South Korea. Her research interests include cooling of electric vehicle motors and fuel cell.

Taeyoung Beom obtained his B.S. in Mechanical Engineering from Chung-Ang University, Seoul, South Korea. His research interests include thermodynamics and cooling rotor of the electric vehicle motors.

Youngkyo Kim obtained his B.S. in Mechanical Engineering from Chung-Ang University, Seoul, South Korea. His research interests include thermodynamics and cooling rotor of the electric vehicle motors.

Dongkyu Kim is a Professor of Mechanical Engineering, Chung-Ang University, Seoul, Korea. His research interests include thermodynamics and polymer electrolyte membrane fuel cell, and fuel cell vehicles.

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Han, N., Kim, R., Lee, H. et al. Analysis of flow field in the motor-reducer assembly with oil cooling under real driving conditions. J Mech Sci Technol (2023). https://doi.org/10.1007/s12206-023-0239-6

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  • DOI: https://doi.org/10.1007/s12206-023-0239-6

Keywords

  • Churning phenomenon
  • Cooling performance
  • Electric vehicles
  • Flow field
  • Oil cooling
  • Thermal management