DAİRESEL ÇARPAN BİR JETLE SOĞUTMANIN AKIŞ DİNAMİĞİ ETKİLERİNİN DENEYSEL OLARAK İNCELENMESİ

Öz

Bu çalışmada, dairesel çarpan jetin ısı transferi ve akış dinamiği üzerindeki etkileri deneysel olarak incelenmiştir. Çalışmada, jet akımı için çapı d =13.8 mm olan bir alüminyum boru kullanılarak, Reynolds sayısı 5000−25000 aralığında deneyler gerçekleştirilmiştir. Lüle ile çarpma yüzeyi arasındaki mesafe (h/d), farklı değerlerde değiştirilerek (2−10) jetin performansı değerlendirilmiştir. Yerel Nusselt sayıları (Nu), durma noktasındaki Nusselt sayısı (Nu0) ve ortalama Nusselt sayıları (Nuavg) detaylı şekilde analiz edilmiştir. Sonuçlar, h/d mesafesinin ve Reynolds sayısının ısı transferi performansı üzerinde önemli etkileri olduğunu göstermiştir. Artan Reynolds sayısı ve uygun h/d mesafeleri, durma noktasında daha yüksek ısı transferine olanak sağlamıştır. Bu bulgular, çarpan jetlerin enerji verimli soğutma uygulamalarındaki potansiyelini ortaya koymaktadır.

Anahtar Kelimeler

• Çarpan jetler
• Isı transferi
• Türbülans şiddeti

Experimental Investıgation Of Flow Dynamics Effects Of Cooling With A Circular Impınging Jet

Abstract

This study experimentally investigates the effects of a circular impinging jet on heat transfer and flow dynamics. Using an aluminum nozzle with a diameter of d=13.8 mm, experiments were conducted within the Reynolds number range of 5000−25000. The nozzle-to-plate distance (h/d) was varied between h/d=2−10 to evaluate the jet's performance. Local Nusselt numbers (Nu), stagnation point Nusselt number (Nu0), and average Nusselt numbers (Nuavg) were analyzed in detail. The results demonstrated that both the nozzle-to-plate distance and Reynolds (Re) number significantly influence heat transfer performance. Increased Reynolds numbers and optimal h/d distances led to enhanced heat transfer at the stagnation point. These findings highlight the potential of impinging jets for energy-efficient cooling applications. The optimal nozzle-to-plate distance for maximum heat transfer was found to be h/d = 6, with a 30.5% increase in Nusselt number at Re = 25000. Additionally, turbulence intensity played a crucial role in heat transfer performance, particularly in the wall jet region, where it enhanced mixing and improved thermal efficiency.

Keywords

• Impinging jets
• Heat Transfer
• Turbulent intensity

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