Elektrik motorlarında stator halkası yüzeyine püskürtmeli soğutmanın geçici ısı transfer kapasitesinin sayısal simülasyonu

Öz

Elektrikli araç motorlarının sürekli artan güç yoğunluğundan kaynaklanan ve geleneksel soğutma teknolojilerinin başa çıkmakta zorlandığı aşırı ısınma sorununu ele almak için, bu çalışma motor statorunun halka şeklindeki yüzeyinde geçici bir ısı transferi sayısal modeli geliştirmiştir. Meme sayısı, püskürtme akış hızı (Q) ve meme yüksekliğinin stator yüzeyinin ısı transfer kapasitesi üzerindeki etkileri araştırılmıştır. Simülasyon sonuçları, meme sayısının artmasının sıvı film kaplamasını artırdığını ve sıcaklık homojenliğini iyileştirdiğini göstermektedir. Ek olarak, Q'nun artması damlacık çarpma kinetik enerjisini artırır, sıvı film kalınlığını azaltır ve böylece maksimum yüzey sıcaklığını ve sıcaklık farkını düşürür. Dahası, meme yüksekliğinin artması daha homojen damlacık dağılımı sağlamaya, sıçramayı bastırmaya ve soğutma kapasitesini daha da iyileştirmeye yardımcı olur. 4000 Hz'lik bir titreşim frekansında, nozul sayısının 12'den 18'e, Q değerinin 4000 mL/dak'dan 8000 mL/dak'ya ve nozul yüksekliğinin 20 mm'den 30 mm'ye çıkarılması, maksimum sıcaklıkta sırasıyla 25,3 °C, 38,8 °C ve 13,1 °C'lik bir düşüşe neden olmaktadır.

Anahtar Kelimeler

• Motor statoru
• Püskürtmeli soğutma
• Sayısal model
• Sıvı film kalınlığı
• Sıcaklık dağılımı

Numerical simulation of transient heat transfer capability of stator ring surface spray cooling in electric motors

Öz

To address the overheating issue caused by the continuous increase in power density of electric vehicle motors, which traditional cooling technologies struggle to handle, this study develops a transient heat transfer numerical model on the annular surface of the motor stator. The effects of nozzle number, spray flow rate (Q), and nozzle height on the heat transfer capability of the stator surface are investigated. The simulation results show that increasing the number of nozzles enhances the liquid film coverage and improves temperature uniformity. Additionally, increasing the Q enhances the droplet impact kinetic energy, reduces the liquid film thickness, and thus lowers the maximum surface temperature and temperature difference. Furthermore, increasing the nozzle height helps achieve more uniform droplet distribution, suppresses splashing, and further improves cooling capability. Under a vibration frequency of 4000 Hz, increasing the nozzle number from 12 to 18, the Q from 4000 mL/min to 8000 mL/min, and the nozzle height from 20 mm to 30 mm results in a decrease in the maximum temperature by 25.3 °C, 38.8 °C, and 13.1 °C, respectively.

Anahtar Kelimeler

• Motor stator
• Spray cooling
• Numerical model
• Liquid film thickness
• Temperature distribution

Kaynakça

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