Ertan BUYRUK, Gökhan GÜNHAN, Ahmet FERTELLI

BİR BUZ DEPOLAMA TANKINDA SOĞUTUCU GEOMETRİSİNİN BUZ OLUŞUMUNA ETKİLERİNİN SAYISAL OLARAK İNCELENMESİ

Bu çalışmada, içerisinde su bulunan dikdörtgen bir soğu depolama tankına yerleştirilen farklı silindir geometrilerinin buz oluşumuna etkilerinin karşılaştırılması amaçlanmıştır Bu amaçla FLUENT paket programı kullanılarak akış alanının zamana bağlı sayısal çözümü yapılmıştır. Dikdörtgen tank iki boyutlu modellenerek analizler akış alanı simetrik olduğundan tankın yarısı için yapılmıştır. Tank içerisindeki su sıcaklığı 0 °C, 4 °C ve 12 °C olarak alınıp, silindir yüzey sıcaklığı -10 °C kabul edilerek, farklı geometrilerdeki silindir modelleri için Ab/As oranı (Buz alanı / kesit alanı), sıcaklık dağılımı, hız vektörleri ve sıvı oranları hesaplanmıştır. En yüksek buz oluşum oranları dairesel kesitli silindir modelinde görülmekle beraber, altıgen modeldeki katılaşma oranları da dairesel modele yakındır. Bununla beraber Tsu=12°C için kare ve üçgen 2 modellerinin katılaşma oranları arasındaki farkın da 0 °C ve 4 °C ile karşılaştırıldığında daha fazla olduğu görülmektedir

NUMERICAL INVESTIGATION OF THE EFFECTS OF GEOMETRIC VARIATIONS OF COOLING TUBES FOR ICE FORMATION IN ICE STORAGE TANK

In the present study, it is aimed to compare the effects of different geometries located in a rectangular ice storage tank on ice formation. For this aim FLUENT package program was used to solve the flow numerically depending on time. Rectangular tank was modeled in two dimensional and calculations were carried out on half of tank due to symmetry. Water temperature was assumed in the tank as 0 °C, 4 °C and 12 °C, cylinder surface temperatures were taken as -10 °C. Ratio of Ai/Ac (Formed ice area/Cross sectional area), temperature distribution, velocity vectors and liquid fraction were computed for different cooler geometries as circular, hexagonal, square, triangle 1 and triangle 2. The highest ice formation rate was seen in circular model, which was followed by hexagonal, triangle 1, square and triangle 2 models. While the highest solidification rate was seen in circular cross-section cylinders, solidification rates in hexagonal cylinders were rather close to the circular cross-section cylinders. However, the difference between square and triangle 2 models increased even more compared to cases when Ti= 0 °C and Ti= 4 °C

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