THE EXPERIMENTAL AND NUMERICAL INVESTIGATION OF THE THERMAL BEHAVIORS OF A JACKETED HEAT EXCHANGER WITH A STIRRER

Öz

In this study, the thermal performance of a jacketed heat exchanger with a stirrer was experimentally and numerically investigated under different jacket side water inlet temperature and flow rate conditions. In the numerical study, a three-dimensional computational fluid dynamics (CFD)model of the heat exchanger was generated and the analyzes were performed with the ANSYS-Fluent software package. In addition, a stirrer was added to both the experimental and the numerical study to obtain the effects of the stirrer on the temperature and velocity values of the water in the tank. It was seen that the results of the analyzes performed under similar conditions to the experimental study were in good agreement with the experimental study. It was concluded that the effect of the flow rate decreases with increasing inlet temperature. When the stirrer was activated and the flow rate was increased from 0.5 to 2.5 l/min in 30, 40, and 50°C inlet temperature conditions, the time to reach the target temperature inside the tank decreased from approximately 1600 to 900, from 2500 to 1350, and from 4900 to 1400, respectively. In general, it was observed that the effect of the stirrer increased with increasing inlet temperature in all flow rate conditions.

Anahtar Kelimeler

• Stirred Tank
• Jacketed Heat Exchanger
• CFD

Karıştırıcılı Ceket Tip Isı Değiştiricilerin Isıl Davranışlarının Deneysel ve Sayısal Olarak İncelenmesi

Öz

Bu çalışmada, karıştırıcılı ceket tip bir ısı değiştiricisinin ısıl performansı ceket tarafı su giriş sıcaklık ve debi koşulları altında deneysel ve sayısal olarak incelenmiştir. Sayısal çalışmada, ısı değiştiricisinin üç boyutlu hesaplamalı akışkanlar dinamiği (HAD) modeli oluşturulmuş ve analizler ANSYS-Fluent paket programı kullanılarak yapılmıştır. Ayrıca tank içerisindeki suyun sıcaklık ve hızına olan etkisini inceleyebilmek için hem deneysel hem de sayısal çalışmada tank içerisine bir karıştırıcı eklenmiştir. Deneysel çalışmayla benzer koşullar altında gerçekleştirilen analiz sonuçlarının deneysel çalışma sonuçlarıyla uyumlu olduğu görülmüştür. Artan giriş sıcaklığıyla debi etkisinin azaldığı sonucuna varılmıştır. Karıştırıcı devredeyken ve debi 0.5’ten 2.5 l/dk’ya çıkarıldığında, hedeflenen sıcaklığa ulaşma süreleri 30, 40 ve 50°C giriş sıcaklık koşullarında sırasıyla 1600’den 900’e, 2500’den 1350’ye ve 4900’den 1400’e azalmıştır. Genel olarak tüm debi koşullarında karıştırıcı etkisinin artan giriş sıcaklık değeriyle birlikte arttığı gözlenmiştir.

Anahtar Kelimeler

• Karıştırıcılı Tank
• Ceket Tip Isı Değiştirici
• HAD

Kaynakça

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