6.A CD nozzle with Po - Satm; To = 400K, throat arca At - 104 mºis designed for isentropic fow to produce an exit Me=2.4
Posted: Sat May 21, 2022 11:54 am
6.A CD nozzle with Po - Satm; To = 400K, throat arca At - 104 mºis designed for isentropic fow to produce an exit Me=2.4 with air. Find the required operating pressure ratio ranges between the background pressure and source stagnation pressure (P\/P.) for cach of the following scenarios: (a) isentropic flow throughout and M> 1 at the exit; (b) isentropic flow throughout and M<1 at the exit; (e) a normal shock at As = 1.688 At; (d) what is the mass flow rate for case 'e"?; (e) what Pb/Po ratio would reduce the mass flow of part d' by 20%? Illint: The three cascs a,b,c arc like those shown in fig 11.15, corresponding to cases d, i, and e! Approx. Ans: (a) Pb/Po<0.08: (b) Pb/Po > 0.8: (c) Pb/Po -0.75; (d) m-0.16 kg/s: (e) Pb/Po - 0.7 1