Knowing the available turbine net head and flow rate, Ht and Qt,
and the required turbine speed, Nt, Eq. (1a) and Eq. (1b) can be used
to select a suitable pump impeller based on readily available
manufacturers data. The selected pump impeller was a KSB Ajax I.S.
series impeller with turbine runner outlet diameter, D ¼ 226 mm.
No blade geometry modifications were performed. The rated values
(BEP) of the pump unit from which the impeller is taken, and the
predicted and actual turbine performance are given later in Table 1
(Section 4).