ISI KÖPRÜLERİNDE HİGROTERMAL PERFORMANSIN VE ISI KAYIPLARININ İNCELENMESİ

Abstract

Enerji verimliliğinde önemli bir potansiyele sahip olan binalarda enerji kaybının en büyük kısmı bina kabuğundan gerçekleşmektedir. Günümüzde; farklı kalınlık ve özellikteki çeşitli katmanlardan oluşan bina kabuğunda, ısı kaybının azaltılmasında, ısı köprülerinden kaçınmaya yönelik uygulamalar en temel yaklaşımlardan biridir. Diğer bileşenlere oranla ısı iletiminin daha fazla olduğu ve nem problemlerinin öncelikle karşılaşıldığı alanlar olan ısı köprülerinin bina enerji performansının değerlendirilmesinde önemi büyüktür. Günümüzde yaygın olarak uygulanan betonarme karkas yapım sisteminde çeşitli nedenlerle çok sayıda ısı köprüsü meydana gelmektedir. Köşe noktalarında meydana gelen ısı köprüleri binanın ortalama ısı geçirgenliğini önemli ölçüde etkiler. Aynı zamanda yoğuşma ve küf oluşumunun da yaygın görüldüğü bölgelerdir. Bu bölgelerin yalıtım durumu da ısıl ve higrotermal performansı etkilemektedir. Tasarım aşamasında bina kabuğunun higrotermal performansı hesaplanarak gerekli önlemler alınmalıdır. Bu amaçla çeşitli benzetim araçları kullanılmaktadır. Böylece tasarım aşamasında bina kabuğunun enerji, konfor ve sağlık koşullarını sağlaması mümkün olabilecektir. Bu çalışmada ısı köprülerindeki ısı kayıpları ve higrotermal performans araştırılmıştır. Mevcut bir konut yapısının köşe noktasında meydana gelen ısı köprüleri, yalıtımsız, kısmi yalıtımlı ve dışardan yalıtımlı olma durumlarına göre değerlendirilmiştir. Çalışma kapsamında Quick Field 6.3 ve Wufi 2D-4.3 programları aracılığıyla yapılan analizlerden ısı köprülerinin kısmi yalıtılması durumunda kesintisiz dışarıdan yalıtımlı olma durumuna göre %37 daha fazla ısı kaybı meydana geldiği görülmüştür. Aynı zamanda higrotermal performans açısından da kesintisiz dışardan yalıtımlı durumda yoğuşma riski görülmemektedir.

Keywords

• Isı köprüsü
• ısı kaybı
• yoğuşma
• higrotermal performans
• ısı yalıtımı

INVESTIGATION OF THERMAL BRIDGE EFFECT ON HEAT LOSSES AND HYGROTHERMAL PERFORMANCE

Abstract

The largest energy loss in buildings, which have a significant potential for energy efficiency, occurs in the building envelope. At present, one of the most basic approaches to reducing heat loss in the building envelope, which consists of various layers of different thicknesses and properties, is to avoid thermal bridges. Thermal bridges are areas where heat conduction is higher than other components of the building and where moisture problems are primarily encountered and are of great importance in the evaluation of building energy performance. In today's widely applied reinforced concrete frame construction system, many thermal bridges occur for various reasons. Thermal bridges occurring at the corner points of the building significantly affect the average thermal transmittance of the building. These areas are also the areas where condensation and mould formation are common. The insulation status of these regions affects the thermal and hygrothermal performance. Necessary measures should be taken by calculating the hygrothermal performance of the building envelope during the design phase. Various simulation tools are used for this purpose. In this way, the building envelope can provide energy, comfort, and health conditions during the design phase. In this study, heat losses and hygrothermal performance of thermal bridges are investigated. The thermal bridges occurring at the corner point of an existing residential building were evaluated according to the conditions of uninsulated, partially insulated and externally insulated. Analyses within the scope of the study were carried out with Quick Field 6.3 and Wufi 2D-4.3 programs. In the analyses, it is seen that 37% more heat loss occurs in the case of partial insulation of thermal bridges than in the case of continuous external insulation. Likewise, in terms of hygrothermal performance, there is no condensation risk in the case of continuous external insulation.

Keywords

• Thermal bridge
• heat loss
• condensation
• hygrothermal performance
• thermal insulation

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