Question

Air enters a diffuser at 102 KPa , 57 Celcius , and 285 m/s and exits at 303 KPa , 10 Celcius , and 12 m/s. The area of the inlet of the diffuser is 97 cm2. Find the mass flow rate of air (kg/s), find the area of the exit of the diffuser (cm2), find the average heat transfer time rate (kW)

Answer 1

Solution he ideal Assuming air to gas. specific volume of air can be can be determined by ideal gas relation. RT v (0.287 klai m?/kg.k) (330k) (102 kPa.) P. as vi 0.928. m me/kg Then ni mall flow rate of air; Ru, A, tu tu, a, ㅗ (285 mes )" (97x104m) 201 928 m²/kg) mi a 2.98 kgls .(0.287 kPa, m?/kg-k) x (283K) (303 kPa) 2 RT2 P, ų

2 0.268 me / kg 2) Now, im fu, A, 2 f u A₂ m 20 L'u, Ar V mv. иу 2(2.98 kgls; (0.268 m² /kg) (12 mis) Az 0.0666m² 666 cine Aza 7 Energy balance: Q - joo m 2 طا) h) + Wi-u? en un

330.34 kJ 코 kJ /kg from property table of air, hich @330 K - 283.14 kJ / kg hr =h@288k Now, å. =(2,98 kg is) (283.14%) •14 KJ - 330.34 KJ kg 12 mis²_ (285 mys) + 2 47.2 kJ 40840.5 I kg kg = (2.98 kg) »)[-47 =(2.98 kg) {-47.2 16 h 40.54 ki Ry 261.46 kW Q