Outlet velocity and mass flow in a convergent-only nozzle

2 Outlet velocity and mass flow in a convergent only nozzle 

The velocity of the gas reaching the turbine blade will increase as the pressure ratio falls down as far as r]im(Pic/Pot), but it will remain constant thereafter. Thus it may be calculated using equation (14.45) as  

While we have made allowance for a possible increase in velocity downstream of the nozzle, we should remember that the mass flow is still subject to an absolute choking limit. The mass flow under all conditions is given by combining equations (14.49) and (14.57)  

The differentiation between the general polytropic index, mo, and the value of the polytropic index at 

3 Nozzle efficiency in choked conditions for a convergent-only nozzle 

---