Question

QUESTION 1 A centrifugal compressor delivers 10 kg/s with total pressure rise of 5:1, and operates at a speed of 15000 rpm. The inlet conditions are 1 bar, 27 °C and 140 m/s. Assume slip factor =0.92, isentropic efficiency = 0.81 match the correct answer for the following: - The rise in total temperature in K - The speed of the compressor Uz in m/s - Blade tip diameter in mm - The power to drive the compressor in kW A. 345 B. 486 C. 2173 D. 2341 E. 247 F. 625 G. 216 H. 2214 1. 717 J. 2521 K. 521 L. 235 M. 675 N.619

Answer 1

Solution Thet Bilde liven that mass flow rate mi lokgls Pressure ratio hp = 5 Speed = 15000rpm Soler Condinon P l bar Ps= slip facor=0.92 7,= 27c = 2424236,5 luomis - 3ook Me isentropic efhciency: 0.81 la] The Rise in total temperature AT= Tora . - Ta-ti Tos- TA we know that Tg = (rp). To

2=1.4 for air Tour de San 300 1. To: 475.141K Now Tes - Tos I (T2-T) Tas - osi (475.14 - 300 ) tam Tas = 516.23k ATE Tas - Ti = 216.23 16 of Compressor we - know that m du = Actual power mcp (Tas-To) 10 x 0.92x U 1x 1.005% 216.23x10° Ly ✓ 1005x 216.23 0.92 - 486.olms I c ] Blade timp U₂ = diameter 7 D2 N2 60

U2 x 60 D2 15000 XTI 486.01 X 60 SED. 0.618 ma Ispoo TT Dia meter of blade tip: 618mm/ d ] power input = mcp at = 10x 1.005% 216.23 - 2 173.11 kW Answen The Rise in total Hem pe Dice in total temperature ink → 6 216 The speed of the Compressor Ozinm/s B. 486 c] Blade tip d'ameter in mm N. 619 - The power to drive th Compressorintos c.2173