Journals / Teknik Dergi / 2019 / Cilt: 30 - Sayı: 4
Roughness Coefficient of a Highly Calcinated Penstock
- Journal
- Teknik Dergi
- Pages
- 9309–9325
- DOI
- —
Abstract
When highly calcinated water is transferred through the penstock of a hydropower plant it leaves a residue on the pipe surface. Accumulated residue over time causes a change in the roughness of the pipe surface thus friction losses in the system. The effect is a change in head and discharge relation for the turbines. A multimethodology is proposed for determining the apparent surface roughness value (ε) by means of friction factor f and measuring arithmetic mean deviation of the roughness profile (Ra), root mean square roughness (Rq) and peak and valley roughness (Rz). It is found that a surface roughness value (ε) of 0.3mm can be used for calcinated surfaces which is much higher than steel surfaces but smaller than concrete.
Özet
When highly calcinated water is transferred through the penstock of a hydropower plant it leaves a residue on the pipe surface. Accumulated residue over time causes a change in the roughness of the pipe surface thus friction losses in the system. The effect is a change in head and discharge relation for the turbines. A multimethodology is proposed for determining the apparent surface roughness value (ε) by means of friction factor f and measuring arithmetic mean deviation of the roughness profile (Ra), root mean square roughness (Rq) and peak and valley roughness (Rz). It is found that a surface roughness value (ε) of 0.3mm can be used for calcinated surfaces which is much higher than steel surfaces but smaller than concrete.