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

Yıl 2019, Cilt: 25 Sayı: 4, 387 - 395, 28.08.2019

Koray Karabulut Doğan Engin Alnak

Öz

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.

Anahtar Kelimeler

Forced convection, Moist transfer, Numerical analysis

Nemli nesnelerin zorlanmış taşınım ile hava jeti çarpmalı kurutulmasının incelenmesi

Öz

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

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