Experimental study on the aeration performance of water jet which is performed by a venturi device

Abstract

The purpose of aeration in water is to transfer or remove gases from the water. Dissolved oxygen is critical for living life. In water engineering, aeration and oxygen transfer using water jets are common. In this study, various venturi nozzles with air holes in the throat portion were manufactured and meaningful experiments were conducted to determine their oxygen transfer efficiency and aeration performance., the venturi nozzles with throat diameters 14, 17 and 20 mm were used in the experimental study. The ratio of the diameter of the air holes to the diameter of the throat portion is taken as 0.1, 0.2 and 0.3. Different experiments were carried out for nine different hole diameters. In addition, the ratio of the throat portion length to the throat portion diameter was taken as 1.00 and 0.50. In addition, comprehensive experiments were carried out by considering the ratio of outlet length to outlet diameter for all nozzles, 1 and 2, and for one venturi, 1, 2, 3, 4 and 5. The experiments were also conducted for the circular nozzle to make comparisons. In this study, venturi nozzles gave better results than circular nozzles, and higher aeration performance values were obtained for the ratios 0.2 and 0.3, 1, 0.50 and 0.50. It was found that the aeration performance of the venturi nozzle was approximately 6.5 times higher than the air entrainment rate performance of the circular nozzle and 2.5 times higher in terms of oxygen transfer.

Keywords

• Water jet
• venturi
• aeration
• oxygen transfer
• nozzle

Venturi aygıtı ile oluşturulan su jetinin havalandırma performansının deneysel incelenmesi

Öz

Sularda havalandırmanın amacı gazların sulara transferi veya sulardan uzaklaştırılmasıdır. Çözünmüş oksijen canlı yaşamı için kritik öneme sahiptir. Su mühendisliğinde, su jetleri kullanılarak havalandırma ve oksijen transferi işlemine sık rastlanır. Bu çalışmada boğaz bölgesinde hava deliğine sahip olan çeşitli venturi ağızlıklar imal edilerek, bunların oksijen transfer verimleri ve havalandırma performansları deneysel olarak incelenmiştir. Çalışmada boğaz bölgesi çapı d=14, 17 ve 20 mm olan venturiler kullanılmıştır. Hava delikleri çapının boğaz bölgesi çapına oranı da hd/d=0.1, hd/d=0.2 ve hd/d=0.3 olarak alınmıştır. Dokuz farklı delik çapı için farklı deneyler yapılmıştır. Bunun yanı sıra boğaz bölgesi uzunluğunun boğaz bölgesi çapına oranı /d=1.00 ve/d=0.50 olarak alınmıştır. Ayrıca bütün ağızlıklar için çıkış uzunluğunun çıkış çapına oranı L/D=1 ve L/D=2 ve bir adet venturi için de L/D=1, 2, 3, 4 ve 5 değerleri de göz önüne alınarak kapsamlı deneyler yürütülmüştür. Karşılaştırmalar yapabilmek için dairesel ağızlık için de deneyler yapılmıştır. Bu çalışmada venturi ağızlıkların dairesel ağızlıklara göre oldukça iyi sonuçlar verdiği, hd/d=0.2 ve hd/d=0.3, L/D=1, /d=0.50 ve d/D=0.50 oranları için daha yüksek havalandırma performansı değerleri elde edilmiştir. Venturi ağızlığın havalandırma performansının dairesel ağızlığın havalandırma performansından yaklaşık olarak 6.5 kat ve oksijen transferi açısından 2.5 kat daha fazla olduğu bulunmuştur.

Anahtar Kelimeler

• Su jeti
• venturi
• havalandırma
• oksijen transferi
• nozul

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