Sıcak Sulu Isıtma Sistemlerinde Isıtıcı Tipinin Doğal Taşınımı Üzerindeki Etkisinin Sayısal İncelenmesi

Öz

Bu çalışmada, farklı uzunluklara sahip odalarda sıcak sulu ısıtma sistemlerinde kullanılan iki yaygın yöntem olan radyatörle ısıtma ve yerden ısıtma sistemlerinin, oda içerisindeki doğal taşınım davranışı, sıcaklık dağılımı ve hız alanı üzerindeki etkileri sayısal olarak incelenmiştir. Bu kapsamda, 3 m, 5 m ve 7 m uzunluğundaki odalar ANSYS Fluent paket programında iki boyutlu olarak modellenmiş ve oluşturulan sayısal model literatürdeki deneysel verilerle karşılaştırılarak doğrulanmıştır. Analizler sonucunda, yerden ısıtma sisteminin farklı oda uzunluklarında ölçekten bağımsız, daha homojen ve dengeli bir ısıl performans sergilediği belirlenmiştir. Buna karşılık radyatörle ısıtma yönteminin lokal ısıtma karakteri nedeniyle oda uzunluğu arttıkça sıcaklık dengesizliğine ve daha yüksek hız gradyanlarına yol açtığı gözlemlenmiştir. Elde edilen bulgular, geniş hacimli iç mekânlarda yerden ısıtmanın ısıl konfor açısından daha avantajlı olduğunu ortaya koymaktadır.

Anahtar Kelimeler

• Doğal Taşınım
• HAD
• Odanın Isıtılması
• Isı Transferi

Numerical Investigation of the Effect of Heater Type on Natural Convection in Hot-Water Heating Systems

Abstract

In this study, the effects of two commonly used hot-water heating methods radiator heating and underfloor heating on natural convection behavior, temperature distribution, and velocity fields inside rooms of different lengths were numerically investigated. For this purpose, rooms with lengths of 3 m, 5 m, and 7 m were modeled in two dimensions using the ANSYS Fluent software package. The numerical model was validated by comparison with experimental data from the literature. The results show that the underfloor heating system provides a scale-independent and more uniform thermal performance across different room lengths, while the radiator heating method, due to its local heating characteristics, leads to temperature non-uniformities and higher velocity gradients, particularly in longer rooms. The findings indicate that underfloor heating offers significant advantages in terms of thermal comfort in large indoor spaces.

Keywords

• Natural Convection
• CFD
• Room Heating
• Heat Transfer

Kaynakça

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