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4. Efficiency and power measurement
4.1 On a scale model
To establish a performance hill, tests are generally carried out under constant head and without cavitation, i.e. the sigma displayed is significantly higher than the installation sigma. This is achieved by maintaining the downstream tank at atmospheric pressure. This makes it much easier to automate the measurement, otherwise you'd have to adjust the sigma manually, point by point, using the vacuum pump.
The influence of sigma is taken into account only at guaranteed yield points under guaranteed drops during cavitation tests.
Since mechanical losses are different between model and prototype, the hydraulic efficiency η h is calculated from the mechanical power P...
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Efficiency and power measurement
Also in our database
Document database Hydraulic, aerodynamic and thermal machines
Standard
- Hydraulic turbines, storage pumps and pump-turbines – Acceptance tests on model - CEI 60193:1999 - 1999
Website
Alstom power hydro http://www.hydro.power.alstom.com
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