where subscripts 1 and 2 refer to measurements at high and low
pressure side, respectively. The hydraulic power available to the
turbine is therefore a product of the test specific energy and the
mass flow rate calculated as
Ph ¼ EðrQÞ½W (3)
The power transferred to the turbine shaft is given by
Ps ¼ 2pn$T½W (4)
where the torque, T, is calculated from the measured shaft strain as