Steam issues from the nozzles of a de-Laval turbine with the velocity of 920 m/s. The nozzle angle is 20°, the mean diameter of the blades is 25 cm and the speed of rotation is 20,000 r.p.m. The steam flow through the turbine is 0.18 kg/s. If the ratio of relative velocity at outlet from the blades to that at inlet is 0.82. Calculate, (a) Tangential force on blades per second (b) Workdone on blades per second (c) Power of the wheel (d) Efficiency of blading (e) Axial force on blades' (f) Inlet angle of blades for shockless inflow of steam Assume that the outlet angle of blades is equal to the inlet angle.

Steam issues from the nozzles of a de-Laval turbine with the velocity of 920 m/s. The nozzle angle is 20°, the mean diameter of the blades is 25 cm and the speed of rotation is 20,000 r.p.m. The steam flow through the turbine is 0.18 kg/s. If the ratio of relative velocity at outlet from the blades to that at inlet is 0.82. Calculate, (a) Tangential force on blades per second (b) Workdone on blades per second (c) Power of the wheel (d) Efficiency of blading (e) Axial force on blades' (f) Inlet angle of blades for shockless inflow of steam Assume that the outlet angle of blades is equal to the inlet angle.

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 centrifugal pump in Fig. has r1 = 15 cm,r2 = 25 cm, b1 =b2 = 6 cm, and rotates counterclockwiseat 600 r/min. A sample blade is shown. Assume α1 = 90°.Estimate the theoretical flow rate and head produced, forwater at 20°C, and comment.
A Pelton wheel has to develop 12 MW under a head of 300 m at a speed of 500 rpm. If the diameter of the jet is not to exceed 1/9 of the wheel diameter, calculate the quantity of flow and no. of jets. Assuming eo = 85%, Cv = 0.97, and Ф = 0.45.
A Pelton wheel works at the foot of a dam because of which the head available at the nozzle is 400 m. The nozzle diameter is 160 mm and the coefficient of velocity is 0.98, The diameter of the wheel bucket circle is 1.75 m and the buckets deflect the jet by 150°. The wheel-to-jet speed ratio is 0.45. Neglecting riction, calculate (1) the power developed by the turbine, (i) its speed and (i) hydraulic efficiency.
An existing impulse turbine-generator installation operates at 450 rpm under a net Head of 520 m. The output current is 60 cycles per second. If a single 18-cm diameter waterjet is used, Cv = 0.98, Øe = 0.45 and ηT = 0.85. Find the flow through turbine in m3/sec.
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.
[5] A Francis turbine operates at its maximum efficiency point at h0 = 0.94, corresponding to a power specific speed of 0.9 rad. The effective head across the turbine is 160 m and the speed required for electrical generation is 750 rev/min. The runner tip speed is 0.7 times the spouting velocity, the absolute flow angle at runner entry is 70 deg from the radial direction and the absolute flow at runner exit is without swirl. Assuming there are no losses in the guide vanes and the mechanical efficiency is 100%, determine (i) the turbine power and the volume flow rate; (ii) the runner diameter; (iii) the magnitude of the tangential component of the absolute velocity at runner inlet; (iv) the axial length of the runner vanes at inlet.
A converging elbow turns water through an angle of 135º in a vertical plane. The flow cross-sectional diameter is 400 mm at the elbow inlet, section (1), and 200 mm at the elbow outlet,section (2). The elbow flow passage volume is 0.2 m3between sections (1) and (2). The water volume flowrate is 0.4 m3/s, and the elbow inlet and outlet pressures are 150 kPa(gage) and 90 kPa(gage). The empty elbow mass is 12 kg. Calculate the horizontal and vertical anchoring forces required to hold the elbow in place. Assume: a) Steady, Incompressible, Uniform fluid flow at inlet/ outlet. ρwater= 1000 kg/m3.
A Pelton wheel is to be designed for a head of 400 m when running at 500 rpm. The Pelton wheel develops 10000kW shaft power. The blade angle at outlet is 15º. The relative velocity of water is reduced by 5% by moving over the buckets. Velocity of the buckets = 0.45 times the velocity of the jet, overall efficiency = 0.8 and coefficient of the velocity = 0.98. If the Pelton wheel is provided with three nozzle, find (i) The diameter of jet (ii) Total flow rate and the force exerted by a jet on the buckets
A simple carburetor under a certain condition delivers 5.45 kg/h of petrol with an air fuel ratio of 15. The fuel jet area is 2mm2 with coefficient of discharge of 0.75. If the tip of the fuel jet is 0.635cm above the level of petrol in the float chamber and the venturi throat coefficient of discharge of 0.80. calculate: (i) The venturi depression in cm of H2O necessary to cause air and fuel flow at the desired rate. (ii) The venturi throat diameter. (iii) The velocity of air across the venturi throat. You make take density of air = 1.29 kg/m3 and specific gravity of petrol =0.72
A horizontal jet of water issues from a nozzle 7.5 cm diameter under an effective head of 67.5 m and strikes a fixed vertical plate. Find the dynamic thrust on the plate. Take Cv for the nozzle as unity.
Include a free body diagram A fire pump delivers water through a 15 cm main pipe to a hydrant to which is connected an 8 cm. hose, termination in a nozzle 2 cm in diameter. The nozzle, trained vertically up is 1.60 m above the hydrant and 12 m above the pump. The headlosses as follows: pump to hydrant: 3 m. ; at the hydrant 2 m. ; Hydrant to nozzle 12 m. and at the nozzle: 6 % of the velocity head of the nozzle. If the gage pressure at the pump is 550 kPa, to what vertical height can the jet of water thrown?A. 27.5 mB. 29.5 mC. 25.5 mD. 23.5 m
A Francis radial-flow hydroturbine has the following dimensions, where location 2 is the inlet and location 1 is the outlet: r2 = 2.00 m, r1 = 1.30 m, b2 = 0.85 m, and b1 = 2.10 m. The runner blade angles are ?2 = 71.4° and ?1 = 15.3° at the turbine inlet and outlet, respectively. The runner rotates at n. = 160 rpm. The volume flow rate at design conditions is 80.0 m3/s. Irreversible losses are neglected in this preliminary analysis. Calculate the angle ?2 through which the wicket gates should turn the flow, where ?2 is measured from the radial direction at the runner inlet. Calculate the swirl angle ?1, where ?1 is measured from the radial direction at the runner outlet. Does this turbine have forward or reverse swirl? Predict the power output (MW) and required net head (m).