Question

homeWork Problem HW83 Attemps Used 1/20 Due Date - Thu, Jul 30, 2020, 23:59:59 Current Time Thu, Jul 30, 2020, 00:58:21 Air flows through a converging-diverging nozzle/diffuser. Assuming isentropic flow, air as an ideal gas, and constant specific heats determine the state at several locations in the system Note: The specific heat ratio and gas constant for air are given as k-1.4 and R-0.287 kJ/kg-K respectively, --Given Values Inlet Temperature: T1 (K) 358 Inlet pressure: P1 (kPa) 626 Inlet Velocity: V1 (m/s) -83 Area at inlet (om'2) 7.8 Mach number at the exit = 2.38 a) Determine the mass flow rate (kg/s) through the nozzle Your Answer -0.394 Correct! Exact Answer=0.3944 +/- 1.7E-03 b) Determine the Mach number at the inlet. Your Answer 0218 Correct! Exact Answer 0.2188 +/- 9.4E-04 c) Determine the stagnation temperature (K) at the inlet Your Answer=3614 Correct! Exact Answer 361.43.1.4E+00 d) Determine the stagnation pressure (kPa) at the inlet Your Answer 647 07 Correct! Exact Answer 647.24.24E00 c) Determine the temperature (K) at the throat, Your Answer301.16 Correct! Exact Answer 301.1909 + LIE+00 f) Determine the pressure (kPa) at the throat. Your Answer-341 07 Correct! Exact Answer 341.92 -1.3E+00

Answer 1

At 9 ) throat M = 1 M = vt vt a JERTE VE J1.4x28 4X287 x 301.16 Vt = 347.86 m/s * h) in= 8 AVE m in = P² XA VE RT+ 0.394 = 341.07 XAX347.86 0.287 x 301.16 2 * -4 A = 2.87410 m A = 2.87 cm? i) Temperature at exit T2 Tor Itk-1 M² То ето, T2 :-) I 2 = 169.5k 2 361.4 It 1.4-1 2.38

;) Pressure at exit < P2 1-1 Po 1.6 1-1.4 P2 647.07 c (1+1.6.1*2.300) (P2 - 45.68 kfa ic) M = 2.38 M= V2 " V2 JK R Tz az 2.38 = Vz 51.4x2874 169.5 V2= 621.11 m/s Areat at exit e ) in = P2 Az V2 RTZ 0.394 - 45.68 XARX 621.11 0.28 7x 169.5 A₂ = 6.8x104m² 2 Az = 6.8 cm

g- 347.86

h- 2.87

I- 169.5

J- 45.68

K- 621.11

l- 6.8