Impact of Excess Roughness on Power Consumption in Pipe Flows

Year 2017, Volume: 7 Issue: 2/2, 241 - 252, 28.12.2017

Hasan Düz

Abstract

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

Boru Akışında Aşırı Pürüzlülüğünün Güç Tüketimine Etkisi

Abstract

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.

Keywords

boru akışı, pürüzlülük, sürtünme

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