Boru Akışında Aşırı Pürüzlülüğünün Güç Tüketimine Etkisi

Bu çalışmada, artan boru yüzey pürüzlülüğünün pompa güç tüketimine etkisi borulu su akışları için araştırıldı. Akışkan dağıtım sistemlerinde, akış duvarına yapışan kirlilikler veya zamanla oluşan korozyon akış yüzyinin daha pürüzlü olmasına neden olur ve bu da akışa karşı daha fazla sürtünme direnci oluşturur. Burada, alüminyum, bakır, çelik ve galvanizli borulu su akışıyla deneysel bir çalışma gerçekleştirilmiştir. Bu borular çalışmakta olan eskimiş akışkan dağıtım sistemlerinden doğrudan sökülen borulardır. Bu boruların pürüzlülük yükseklikleri deneysel yöntemle ölçüldü ve bulunan pürüzlülük yükseklikleri yeni imal boruların pürüzlülük değerleri ile karşılaştırıldı. Karşılaştırmada aşırı yüzey pürüzlülüğün oluştuğu görüldü. Aşırı pürüzlülük nedeniyle oluşan enerji tüketimi 15000 < Re < 150000 arası Reynolds sayılarında tam gelişmiş türbülanslı yatay boru akışları için gerçekleştirildi. Hesaplamalar artan duvar pürüzlülüğün pompa güç tüketimini ve fatura maliyetini, özellikle yüksek Reynolds sayılarında Re < 105, artırdığı tespit edilmiştir.

Anahtar Kelimeler:

boru akışı, pürüzlülük, sürtünme

Impact of Excess Roughness on Power Consumption in Pipe Flows

In this study, the effect of excess surface roughness on pump power consumption was investigated for water pipe flows. In fluid distribution systems, the impurities adhering to flow wall or the wall corrosion cause the flow surface being more roughly and as a consequent cause to more frictional drag. Here, an experimental study was carried out with water flows inside aluminium, copper, steel and galvanized pipes which are detached directly from the aging fluid distribution assemblings. Roughness heights of these dated pipes was measured by experimental way. The measured roughness heights were compared with new manufacture values, the dated pipes was found more roughly. An energy consumption analysis was carried out for one meter of pipe flow for the Reynolds number between 15000 < Re < 150000. Determinations showed that the friction existed due to excess surface roughness caused the pump power consumption to increase and cost also, especially at high Reynolds number about Re > 105.

Keywords:

pipe flow, roughness, friction,

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