Determination of optimum geometrical parameters of compact heat exchangers using computational fluid dynamics

Bu çalışmada; bir kompakt ısı eşanjörünün çeşitli geometrik parametrelerinin, ısı eşanjörünün ısı transferi ve basınç kaybı gibi performans değerlerine karşı etkileri araştırılmış ve laminar akım koşullarında optimum geometrik parametreleri, Hesaplı Akışkanlar Dinamiği yöntemiyle belirlenmiştir. Çalışmanın sonucunda, araştırılan Reynolds sayısı aralığında, optimum parametreler; boyutsuz plaka açıklığı $F_s$ = 0.233, saptırmalı boru dizilişi düzenine sahip, dalgalı plakalı ve dört-borulu konfigürasyon olarak belirlenmiştir. Bu nümerik çalışmanın sonuçları, deneysel çalışmalarla karşılaştırılmış ve uyumlu sonuçlar elde edilmiştir.

Kompakt ısı aşanjörlerinde optimum geometrik parametrelerin hesaplı akışkanlar dinamiği kullanılarak belirlenmesi

Present study provides information on determination of an optimum •geometrical parameters on compact heat exchangers using Computational Fluid Dynamics. Various geometrical parameters are tested in order to determine optimum dimensions in terms of heat transfer and pressure drop performance of the heat exchanger for the plate fin and tube heat exchangers having plain fin configuration operating under laminar flow condition. It is decided that the optimum value for the non-dimensional fin spacing is $F_s$ =0.233 for the present Reynolds numbers and fin spacing values, In addition, four cylinder configuration of staggered tube layout and wavy fin configuration present good results in terms of heat transfer and pressure drop performance. The validity of the present numerical study is tested against experimental data and it is shown that the results are in good agreement with the experimental data.

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