Question

Steam enters a nozzle at 850 kPa and 270°C at negligible velocity and discharges at a pressure of 500 kPa. Assuming isentropic expansion of the steam in the nozzle, what is the exit velocity and what is the cross-sectional area at the nozzle exit for a flow rate of 0.75 kg/s ?

Answer 1

At Inleti- pressure, Pi -050 kPa Tempevalure , T, - 270C Alleullet! - Soolepa Inlet Veloétig, vi Prz 850kPa V T = 270 / 500 kPa m=onsug m = 0.15 kg og let Velocity Assume inlett velouty gen! T energy Mass flew rale, in = 0.75 493 The general energy balance for the flow system is given by mpoh + 1 ) + g) t o two change to do that I in palestined Land worse transfert 1 min (fi-five) - O Vefama City AG) 1 from threated team table at = Osokia and -T 270 Suporhealed Specifie enthalpy of plantero Steam, W, = 299181 Kg Specifieexiloapy - g = 7:082_KJ Since the prouds is isentropia, therefore from Steam table at § - = 7.000 kft and las Suolla - Specifie enthalpy dloullet: Ĥ, = 2066-27137 and specific Volume, a = 0.43 M/kg Ugikk ugik _ -

Substitule lenown values in equalién 0, we get V 1 210175195')( 2991.81-2866:27)Xlo J x '... ( - 433.95 mi) o we know that _ mass flow rate: map AY oril An i toasigö' c massa asiakid) - 433.95 ms A 2 7.432 koma | outlich emil-sectional aree