An IFR turbine rotor is designed with 13 vanes and is expected to produce 400 kW from a supply of gas heated to a stagnation temperature of 1100 K at a flow rate of 1.2 kg/s. Using Whitfield's optimum efficiency design method and assuming Nis = 0.85, determine (i) the overall stagnation pressure to static pressure ratio; (ii) the rotor tip speed and inlet Mach number, M2, of the flow. Assume C, = 1.187 kJ/kg K and y = 1.33.

An IFR turbine rotor is designed with 13 vanes and is expected to produce 400 kW from a supply of gas heated to a stagnation temperature of 1100 K at a flow rate of 1.2 kg/s. Using Whitfield's optimum efficiency design method and assuming Nis = 0.85, determine (i) the overall stagnation pressure to static pressure ratio; (ii) the rotor tip speed and inlet Mach number, M2, of the flow. Assume C, = 1.187 kJ/kg K and y = 1.33.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

The nozzle angle for an axial flow impulse turbine is 15°. The inlet absolutevelocity is 800 ft./s and the blade speed is 550 ft./s. Axial speed at the inlet andoutlet is assumed to be a constant. Calculate (a) energy transfer E, (b) change intotal (stagnation) and static enthalpies, (c) utilization factor.Ans: E=∆h0=245,038 ft-lbf/slug; ∆h=0; ε=0.77
In a stage of Parson's reaction turbine, the mean diameter of the wheel is 1.05 m and the speed is 3000 r.p.m. The angles of receiving tips are 35° and the discharging tips is 20°. If the steam flow rate is 1 kg/min, draw the velocity diagram for blades and evaluate, (a) Tangential thrust on blades (b) Axial thrust on blades (c) Power developed in the blades and (d) Diagram efficiency.
A single-sided centrifugal compressor has the following data: Inlet stagnation pressure Inlet stagnation temperature Impeller exit Mach number Compressor isentropic efficiency 0.8 Power input factor 110 kPa Mass flow rate 10 kg/s 300 K 0.36 m Inducer tip diameter Inducer hub diameter 1.1 0.18 m Impeller outlet diameter 0.52 m Slip factor 1.05 0.92 Assume that the impeller outlet radial velocity equals the inlet axial velocity. Calculate: (a) Absolute velocity at impeller exit. (b) The compressor pressure ratio (c) The axial width of the impeller at outlet (d) The blade angle at the inducer tip
For a centrifugal compressor designed to have a stagnation pressure ratio of 3.95, determine an appropriate rotation rate for the shaft (to the nearest ten radians per second) when the power input factor is 1.04, the slip factor is 0.88, the isentropic efficiency is 0.79, the impeller diameter is 0.55m and a typical inlet stagnation temperature is 292K. Take Cp=1.005kJ/kg/K and the ratio of specific heat capacities is 1.4.
In a trial run, the De Laval steam turbine at Oman Power Plant rotates at 3000 rpm. The steam is issued from the nozzle at 400 m/s and the nozzle angle is 20o. The blade speed ratio is 0.41and the friction loss in the blade channel is 15%of the kinetic energy corresponding to the relative velocity at the inlet to the blades. As a turbine engineer at that station, how do you determine the (i) power developed by the turbine for a flow rate of 10 kg/s and (ii) suitable inlet and outlet angles for the blades when axial thrust is zero. Also, how would you determine the size of the turbine wheel required? Draw a suitable velocity diagram.
A high pressure axial flow compressor is driven by the jet engine at a speed of 1200rpm.An overall stagnation pressure ratio of 10 is recorded due to the compression of air. The stagnation temperature of air at inlet of the compressor is 325K.Polytropic efficiency of compressor is given as 90% mean radius of the compressor is assumed to be constant and equal to 0.3 m. Determine the total isentropic effeciency and estimate the minimum number of stages required if the stage loading to be less than 0.3
Steam with velocity of 900 m/s exits the nozzle of a 2-stage Curtis turbine with equiangular stator and rotors. The nozzle velocity coefficient is 0.97 and is set at an angle of 67°. The blade speed is equal to 200 m/s with the first and second rotors velocity coefficient of 0.94 and 0.97, respectively. The velocity coefficient of the stator is equal to 0.95. (a) Sketch the pressure and velocity diagram across the stages. (b) Calculate the relative velocity of the steam at the outlet of the first rotor.
A blade pair in an axial flow compressor is being designed. The axial flow component of gas velocity is 174m/s. The engine diameter at the mean blade height is 0.73m and the blade height at the rotor inlet is 0.21m. The rotor's absolute inlet flow angle is 26 degrees. The stagnation conditions at the inlet to the blade pair are 298K and 130kN/m² Using Cp 1.005k/kg/K, R-0.287k/kg/K, and taking the ratio of specific heat capacities as 1.4, calculate the engine mass flow rate to the nearest kg/s
A multi-jet Pelton turbine with a wheel 1.47 m diameter, operates under an effective head of 200 m at nozzle inlet and uses 4 m3/s of water. Tests have proved that the wheel efficiency is 88 per cent and the velocity coefficient of each nozzle is 0.99. Assuming that the turbine operates at a blade speed to jet speed ratio of 0.47, determine:(1) the wheel rotational speed;(2) the power output and the power specific speed;(3) the bucket friction coefficient given that the relative flow is deflected 165°;(4) the required number of nozzles if the ratio of the jet diameter to mean diameter of the wheel is limited to a maximum value of 0.113.
multi-stage high –pressure steam turbine is supplied with steam at a stagnation pressure of 7 MPa and a stagnation temperature of 5000C. The corresponding specific enthalpy is 3410kJ.kg. The steam exhaust from the turbine at a stagnation pressure of 0.7 MPa abs., the steam having been in a super-heated condition throughout the expansion. It can be assumed that the steam behaves like a perfect gas over the range of the expansion and that ᵞ = 1.3. Given that the turbine flow process has a small-stage efficiency of 0.82, determine (1) the temperature and specific volume at the end of the expansion; (2) the re-heat factor. The specific volume of superheated steam is represented by pv=0.231(h-1943), where “p” is in kPa, v is in m3/kg and “h” is in kJ/kg.
A supersonic diffuser for air (y%3D1.4) has an arca ratio of 0.416 with an inlet Mach number of 2.4 (design value). Determine the exit Mach number and the design value of the pressure ratio across the diffuser for isentropic flow. At an off-design value of the inlet Mach number (2.7) a normal shock occurs inside the diffuser. Determine the upstream Mach number and area ratio at the section where the shock occurs and pressure ratio across the diffuser.
1. At what flow angle will the flow become just sonic downstream of the nozzles of a high pressure turbine? The nozzles discharge into an annulus which has a shroud diameter of 250 mm and hub to the shroud diameter ratio is 0.80. The stagnation pressure and temperature are 1500 kPa and 1277 0 C respectively. The mass flow rate is 7 kg/s. The value of R is 286.96 J/(kg.K) and Cp/ R is 4.1