A Kaplan turbine operates a 5 MW generator at 150 rpm, under a head of 5.5 m. The generator efficiency is 93 % and the overall efficiency of the turbine is 88%. The tip diameter of the runner is 4.5 m and the hub diameter is 2 m assuming hydraulic efficiency of 94 % and no whirl at the exit. Determine the whirl velocity at the inlet of the turbine blade in m/s. [up to nearest integer]