Endüstriyel Bir Merdanenin Dönen Jet Kullanarak Soğutulmasının Sayısal İncelenmesi

Öz

Endüstriyel merdanelerin etkin bir şekilde soğutulması, sistemin ve ürünün kalite kaybını önlemek için büyük öneme sahiptir. Merdane yüzeyindeki yüksek sıcaklık farkı, termal gerilmeye sebep olup, merdane yüzeyi ve üründe deformasyonlara neden olabilir. Bu çalışmada, deformasyonları önlemek için endüstriyel bir merdanenin dönen jetler kullanılarak soğutulması farklı parametreler için sayısal olarak incelenmiştir. Reynolds sayısı, yüzey ısı akısı ve akışkanın giriş sıcaklığındaki değişimin endüstriyel bir merdanenin ısı transfer performansı üzerindeki etkileri, merdanenin iç ve dış yüzeyi arasındaki sıcaklık farkı açısından incelenmiştir. Bu sayısal çalışmada ısı transferi ve akışkan akışını modellemek için ANSYS Fluent CFD programı kullanılmıştır. Sonuç olarak Re sayısının 1000'den 1700'e artması, merdane iç ve dış yüzeyi arasındaki sıcaklık farkının %45,4 oranında azalmasını sağlamıştır. Yüzey ısı akısını 5000'den 12500 W/m2'ye çıkarmak, iç ve dış yüzey sıcaklıkları arasındaki farkta %149,4'lük bir artışla sonuçlanmıştır. Soğutucu akışkan giriş sıcaklığının 5'ten 20°C'ye yükseltilmesi, yüzey sıcaklığında bir artışa neden olmuştur, ancak sistemin ısı transfer özelliklerinde önemli bir değişiklik olmamıştır. Bu çalışmanın sonuçlarının daha etkin soğutmalı endüstriyel merdane tasarımına katkı sağlayacağı değerlendirilmektedir.

Anahtar Kelimeler

• Endüstriyel merdane
• Dönen jetler
• Soğutma
• Hesaplamalı Akışkanlar Dinamiği

Numerical Investigation of Cooling an Industrial Roller by Using Swirling Jets

Öz

Effective cooling of industrial rollers has prime importance to prevent the quality degradation of the system and product. High temperature difference on the roller surface may result in thermal stresses and can cause deformations on roller surface and product. In order to prevent these deformations, cooling of an industrial roller by using swirling jets is investigated for different parameters numerically in this study. Effects of Reynolds number, surface heat flux and variation in inlet temperature of the fluid on the performance of an industrial roller are investigated in terms of temperature difference between inner and outer surface of the roller. ANSYS Fluent CFD program is used to simulate heat transfer and fluid flow in this numerical study. As a result, it is obtained that increasing Re number from 1000 to 1700 causes a decrease of 45.4% in the temperature difference between inner and outer surface of the roller. Increasing surface heat flux from 5000 to 12500 W/m2 has resulted in an increase of 149.4% in difference between inner and outer surface temperature. Increasing coolant fluid inlet temperature from 5 to 20°C has resulted in an increase of surface temperature but there is no significant change in heat transfer characteristics of the system. It is evaluated that the results of this study will contribute to design more effective cooled industrial roller.

Anahtar Kelimeler

• Industrial roller
• Swirling jets
• Cooling
• Computational Fluid Dynamics

Kaynakça

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