M.Hakan KAYKAÇ, ZAFER TOSUNOĞLU, Adnan TOKAÇ

600 gözlü geleneksel dip trol ağının 1/10 ölçekli model denemesi

Bu çalışma, Tauti'nin model kurallarına bağlı kalınarak 1/10 ölçekli modeli yapılan 600 gözlü geleneksel dip trol ağının model deneme sonuçlarını içermektedir. Akıntı tankında, üç farklı çekim hızı (2,2.5 ve 3 mil/saat) ve üç farklı yüzdürme kuvvetinde (133.4, 96 ve 0 kg) toplam dokuz deneme gerçekleştirilmiştir. Çekim hızına ve yüzdürücü miktarı ile ilişkili olarak ağ geometrisindeki değişiklikler (ağ direnci, dikey ağız açıklığı ve ağız alanı) ölçülmüştür. Çekim hızı artışı ile ağ üzerindeki direncin arttığı, dikey ağız açıklığının azaldığı ve ağ ağız alanında daralma olduğu gözlenmiştir. Çekim hız ile direnç arasında doğru orantılı, dikey ağız açıklığı ile ters orantılı bir ilişki olduğu tespit edilmiştir. Farklı yüzdürücü miktarları ile yapılan testlerde hız ile direnç arasında ilişki $R_{133,4}=343.1V^{1.5}, R_{96}=360,2V^{1.4} R_o=171,3V^{1.5}$ olarak elde edilmiştir. Yüzdürücü miktarındaki artış ağın dikey ağız açıklığını artırmış fakat ağ üzerinde artan bir direnç yaratmıştır. Model ağda elde edilen deneme sonuçlarına göre, gerçek boyuttaki ağ 2-2,5 mil/saat hızda çekilmelidir. Ayrıca, akıntı tankındaki model ağın görüntülerinin incelenmesi sonucunda geleneksel ağın kanat, maça ve model bölümlerinde yapısal iyileştirmelere gereksinim olduğu tespit edilmiştir.

Anahtar Kelimeler:

balıkçılık, tuzak ağlar

1/10 scale model net experiment of 600 meshes conventional buttom trawl net

1/10 scale model net experiment of 600 meshes conventional bottom trawl net This research comprises 1/10 scale model results of 600 mesh conventional bottom trawl net which was made according to Tauti's modei law. It was carried out with nine experiments in flume tank with three different buoyancy forces (133.4, 96 and 0 kg) and towing speeds (2, 2.5 and 3 mile/hour). The variations in the gear geometry (net resistance, vertical opening and mouth area) were measured in relation to towing speed and buoyancy forces. It was observed increase of the net resistance, decrease of vertical opening and to become narrow net mouth area by increasing the towing speed. It was determined a negative relationship between towing speed and vertical opening and a positive relationship between towing speed and the net resistance. The relationships between net resistance and towing speed in the test made by amount of different buoy were obtained as $R_{133,4}=343.1V^{1.5}, R_{96}=360,2V^{1.4} and R_o=171,3V^{1.5}$ Increasing amount of the buoy was increased vertical opening of. the net but was created an increasing resistance on the net. According to results of model net experiments full scale gear should be towing speed at 2-2.5 mile/hour. In additional, investigation of model net conclusion in flume tank was determined that need to be structural improvements on wing, dan-leno gear and model parts of the conventional net.

Keywords:

fisheries, nets,

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