Instructions:AE/ME5104 Assigned: 23MAR2016Homework #1 Due: 01APR2016
A.B. Linn Page 1 of 3
Total Points: 100
Problem 1: (35 points)
For the specified subsonic axial-flow expander:
• Mass flow; ??̇ = 2 ????/??
• Nozzle inlet stagnation Temp; ??0,???? = 400 ??0
• Absolute nozzle-inlet stagnation pressure; ??0,???? = 3 ?????? = 3??105 ??/??2
• Mean Diameter; ???? = 0.25??
• Blade height @ rotor entry; ?? = 0.1????; = 1/2(???? − ??ℎ)
• Flow angle @ nozzle exit; ??1 = 700
• Drop in stagnation pressure in nozzle; ∆??0 = 0.05 ??????
• Rotor peripheral speed at mean diameter; ???? = 0.5 ?? ????1
Calculate:
• Stagnation and static pressures and temperatures, and Mach number at the rotor inlet plane,
• Rotor rotational speed,
• Nozzle blade-height for constant outer-diameter blading,
• Sketch h-s diagram for the flow through the turbine
AE/ME5104 Assigned: 23MAR2016
Homework #1 Due: 01APR2016
A.B. Linn Page 2 of 3
Problem 2: (35 points)
Given the sketch of the radial inflow turbine and the specifications:
• Nozzle outlet diameter; ???? = 250????
• Rotor inlet diameter; ???????????? = ????
• Nozzle exit angle; 750 ???????? ????????????
• Blade axial height at entrance; ℎ?????????? = 0.1 ?? ????????????
• Turbine nozzles supplied with air at:
o 2 ????/??
o ??0 = 2 ??????;
o ??0 = 125 ??0
• Rotor peripheral speed; ??1 = 0.9 ??1??; ???????????????????? ??????????????????
• Nozzle losses may be neglected;
Calculate:
• Rotor rotational speed
• Static temp and pressure at the nozzle exit and absolute Mach number
Sketch the nozzle expansion on a t-s diagram.
AE/ME5104 Assigned: 23MAR2016
Homework #1 Due: 01APR2016
A.B. Linn P