Analytical and Experimental Investigation of Entropy Generation for an In-line Cross-flow Tube Bank

Öz

One of the most commonly used heat exchangers for waste heat recovery from hot flue gases is cross-flow tube bank heat exchangers. Generally, gas flows outside of the tubes and liquid flows inside the tubes. In recent years, minimum entropy generation is taken as the most important criterion for the dimensioning of heat exchangers. In this study, equations are derived for the calculation of entropy generation due to both heat transfer from hot flue gases that flows outside of the tube bank and pressure losses at constant wall temperature. Generated entropies are determined both due to heat transfer and due to pressure losses and they are discussed.

Anahtar Kelimeler

• Heat exchanger,Tube bank,Heat transfer,Pressure loss,Entropy generation

Çapraz Akışlı Paralel Borulu Boru Demetinde Entropi Üretiminin Analitik ve Deneysel Olarak İncelenmesi

Öz

Sıcak atık gazlardan sıvıya ısı transferinde en çok kullanılan ısı eşanjörlerinden biri de çapraz akışlı boru demeti ısı eşanjörleridir. Boru dışından genelde gaz ve boru içinden de sıvı akmaktadır. Son yıllarda ısı eşanjörlerinin boyutlandırılmasında en önemli kriter olarak minimum entropi üretimi esas alınmaktadır. Bu çalışmada, sabit duvar sıcaklığında boru dışından akan havanın ısı transferinden ve basınç kaybından dolayı entropi üretiminin hesaplanması için gerekli eşitlikler çıkarılmış ve ölçülen değerlerden hem ısı transferi hem de basınç kaybından dolayı entropi üretimleri belirlenmiş ve bulunan değerler tartışılmıştır

Anahtar Kelimeler

• Isı eşanjörü,Boru demeti,Isı transferi,Basınç kaybı,Entropi üretimi

Kaynakça

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