A small inward flow radial gas turbine comprising a ring of

A small inward flow radial gas turbine, comprising a ring of nozzle blades, a radial vaned impeller and an axial diffuser, operates at its design point with a total to total efficiency of 0.90. At turbine entry the stagnation pressure and temperature of the gas is 400 kPa and 1, 140 K. The flow leaving the turbine is diffused to a pressure of 100kPa and has negligible final velocity. Given that the flow is just choked (M_2 =1) at nozzle exit, determine the impeller peripheral speed and the flow outlet angle from the nozzles.

Solution

The impeller peripheral speed is 789rpm while the oulet flow angles are 24 degree and 19 degree .

While in inlet angles are 27 degree and12 degree