Nemli nesnelerin zorlanmış taşınım ile hava jeti çarpmalı kurutulmasının incelenmesi

Bu çalışmada, tam ve düz yarı dairesel olmak üzere iki farklı nemli nesne geometrisinin hava jeti ile kurutulmasının ısı transferi artışı ve nem miktarındaki azalışı üzerindeki etkisi sayısal olarak incelenmiştir. Jet kurutması, nemli nesneden sabit bir jet uzaklığında konumlandırılmış, laminer ve iki boyutludur. Tüm durumlarda, nemli nesnenin çapı, nemli nesneden olan jet uzaklığı ve jet giriş yüksekliği sabit alınmıştır. Farklı jet hızları için nesnelerin etrafındaki akım çizgileri ve eş sıcaklık eğrileri görselleştirilmiştir. Korunum denklemlerini çözmek için sonlu hacim yöntemi olan ANSYS Fluent 17.0 bilgisayar programı kullanılmıştır. Hesaplamalar, Re=100, 200 ve 300 olarak farklı Reynolds sayıları için gerçekleştirilmiştir. Çalışmanın, literatürde var olan sayısal ve deneysel çalışmayla iyi bir uyum içinde olduğu bulunmuştur. Sonuçlar, tam dairesel nemli nesnenin düz yarı dairesel nemli nesneden daha iyi ısı ve nem transferi performansına sahip olduğunu göstermiştir. Ayrıca, Reynolds sayısının artışının ısı ve nem transferi üzerinde olumlu bir etkiye sahip olduğu görülmüştür. Yerel olarak, jet kurutmanın nesnelerin ön taraflarındaki durma noktasına yakın daha etkili oldukları bulunmuştur.

Anahtar Kelimeler:

Zorlanmış taşınım, Nem transferi, Sayısal analiz

Investigation of air jet impingement drying with forced convection of moist things

In this work, the effect of drying with jet of air of two dissimilar moist thing geometries with whole and straight semi-circular on the enhancement of heat transfer and decrement of moisture amount was numerically examined. The drying jet had a laminar flow characteristic and two-dimensional jet situated at a fixed jet space from the moist thing. The moist thing diameter, jet space from the moist thing and height of jet initial were taken as stable in whole situations. Streamlines and isotherms were visualized around the things for dissimilar velocities of jet. A method of finite volume was used to figure out the conservation equations by employing software program of ANSYS Fluent 17.0. Computations were conducted for dissimilar Re, so, Re = 100, 200 and 300. It was obtained well accord with scalar and empirical output found in the reference. The results illustrated that the whole circular moist thing had greater good heat and moisture transfer performance than that of the straight semi-circular moist thing. Furthermore, it was seen that an increase of Re number had an affirmative effect on heat and moisture transfer. As locality, drying of jet was appeared to be most powerful close to the stillness point on the front face of the things.

Keywords:

Forced convection, Moist transfer, Numerical analysis,

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