Define what is meant by the specific speed of (a) a turbine and (b) a pump. (c) A turbine is required to generate 5.5MW of electricity from the regulating releases from Kielder Water reservoir. The nominal head of water available is 47.35m. If the turbine has a rotational speed of 500rpm, by calculating the specific speed determine what sort of turbine is required. (d) A second turbine is required at Kielder to utilise the compensation flow to generate 500kW from the 47.35m head when running at 1000rpm. What sort of turbine should this be? (e) If the turbine in part (c) has a water requirement of 14.1m3 /s, what would be the required flow rate if the turbine was run at 1000rpm, and what would be the new power output?
[(c) Kaplan; (d) Francis; (e) 28.2m3 /s, 44MW]