Effects of Moisture and Direction of Grain on the Thermal Conductivity and Mechanical Properties of Black Alder and Scots Pine

Yıl 2022, Cilt: 22 Sayı: 1, 33 - 39, 31.03.2022

Şeref Kurt Mustafa Korkmaz

https://doi.org/10.17475/kastorman.1095741

Cited By: 1

Öz

Aim of study: Relationships between moisture content and thermal conductivity and mechanical properties of wood species were examined.
Material and methods: Black Alder (Alnus glutinosa L.) and Scots Pine (Pinus sylvestris L.) specimens were used. Thermal conductivity, modulus of rupture, compression strength and impact bending strength values were determined and analyzed. All specimens were examined at 3 different moisture levels which are oven-dry, fiber saturation point (FSP) and completely wet.
Main results: The lowest thermal conductivity value was found in the perpendicular to the grain direction of oven dried Black Alder samples as 0.119 W/mK. The highest thermal conductivity value was found in the parallel direction of Scots pine samples with FSP humidity content as 0.340 W/mK. In addition, the thermal conductivity value parallel to the grain is significantly higher than perpendicular one at all three moisture levels.
Highlights: While there is a positive linear relationship between the moisture content of the wood and its dynamic bending resistance and thermal conductivity; It was found that there is a negative linear relationship between bending strength and compressive strength value.

Anahtar Kelimeler

Thermal Conductivity, Moisture Content, Grain Direction, Impact Bending Strength

Kızılağaç ve Sarıçam Odununun Isıl İletkenliği ve Mekanik Özellikleri Üzerine Rutubet Miktarı ve Lif Yönünün Etkileri

Öz

Çalışmanın amacı: Çalışmada, ağaç malzemenin sahip olduğu nem içeriği ile ısıl iletkenliği ve mekanik özellikleri arasındaki ilişkiler incelenmiştir.
Malzeme ve yöntem: Testlerde kızılağaç (Alnus Glutinosa L.) ve sarıçam (Pinus Sylvestris L.) odunlarından elde edilen örnekler kullanılmıştır. Isıl iletkenlik, eğilme direnci, basınç direnci ve dinamik eğilme (şok) direnci değerleri belirlenmiş ve analiz edilmiştir. Tüm numuneler tam kuru, lif doygunluğu noktası ve tamamen yaş olmak üzere 3 farklı nem seviyesinde incelenmiştir.
Temel bulgular: En düşük ısıl iletkenlik değeri, 0.119 W/mK ile tam kuru haldeki kızılağaç örneklerin örneklerinin liflere dik olarak yapılan ölçümlerinden elde edilmiştir. En yüksek ısıl iletkenlik değeri ise, 0.340 W/mK ile lif doygunluğu rutubetine sahip sarıçam örneklerinde liflere paralel yönde bulunmuştur. Ayrıca, liflere paralel ısıl iletkenlik değeri, her üç nem seviyesinde de dik olandan önemli ölçüde daha yüksek bulunmuştur.
Araştırma vurguları: Ağaç malzemenin nem içeriği ile dinamik eğilme direnci ve ısıl iletkenliği arasında pozitif doğrusal; eğilme direnci ve basınç direnci değeri arasında ise negatif doğrusal bir ilişki olduğu bulunmuştur.

Anahtar Kelimeler

Isı İletkenliği, Nem Miktarı, Lif Yönü, Çarpmada Eğilme Dayanımı

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