Dairesel Kesitli Türbülans Üreticilerinin Etkinlik ve Ekserji Analizi

Bu çalışmada, yatay konumlu ve eş merkezli bir ısı değiştiricisinin iç borusuna yerleştirilen dairesel kesitli türbülatörlerin, ekserji kaybı ve etkinlik üzerine olan etkileri deneysel olarak incelenmiştir. Deneyler; türbülatörler arası mesafenin (a=5 cm, 10 cm ve 15 cm), delik çapının (ç=0.5 mm, 1 mm ve 1.5 mm), delik sayısının 1 ve 2 adet olması durumu için ve Reynolds sayısının 10000 ile 42000 arasında değiştirilmesiyle gerçekleştirilmiştir. Çalışma akışkanı olarak hava kullanılmıştır. Deneylerin yapılabilmesi için gereken buhar bir kazandan elde edilmiş ve ısı değiştiricisinin iki borusu arasındaki boşluğa gönderilerek iç borunun dış yüzeyinin buhar ile temas etmesi sağlanmış ve bu şekilde yüzeyde sabit sıcaklık şartı elde edilmiştir. Çalışma sonunda değişen durumlar için; entropi üretim oranı, ekserji ve etkinlik değerleri değerlendirilmiştir.

Anahtar Kelimeler:

Ekserji, Etkinlik, Isı değiştiricileri, Entropi üretimi

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