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Aswan University Faculty of Engineering
. Electrical Engineering Dept Sheet No. (1) & Hydraulic Machines Heat Engines . 2 nd, Year, Electrical Sec Reaction Turbines
An inward flow reaction turbine, having an external diameter of 1.5 meter -] 1 [
runs at 400 r.p.m. The velocity of flow at inlet is 10 m/s. If the guide blade angle is : 15 , find ,The absolute velocity of water- 1 ,The velocity of whirl at inlet- 2 The inlet vane angle of the runner, and- 3 .The relative velocity at inlet- 4
An inward flow reaction turbine has outer and inner diameters of the wheel -] 2 [
as 1 m and 0.5 m, respectively. The vanes are radial at inlet and discharge is radial at outlet and enters the vanes at an angle of 10. Assuming the velocity of flow to be : constant, and equal to 1 m/d, find the speed of the wheel, and- 1 .the vane angle at outlet- 2
An inward flow reaction turbine is supplied water at the rate of 600 liters/s -] 3 [
with a velocity of flow of 2 m/s. The periphery and velocity of whirl at inlet is 24 m/s and 18 m/s respectively. Assuming the discharge to be radial at outlet, and the : velocity of flow to be constant, find vane angle at inlet, and- 1 .head of water on the wheel- 2
An inward flow reaction turbine is working under a head of 25 m and -] 4 [
running at 300 r.p.m. The velocity of periphery of the wheel is 30 m/s and velocity of flow is 4 m/s. If the hydraulic losses are 20% of the available head and the : discharge is radial, find ,the guide blade angle at outlet- 1 the wheel angle at inlet, and- 2 .the diameter of the wheel- 3
An outward flow reaction turbine has internal and external diameters of 2.4 -] 5 [
and 3 meters respectively. The turbine has a radial discharge of 6 cubic meters/s, and is running at 200 r.p.m. The total head on the turbine is 40 m, and width of the : wheel at inlet and outlet is 30 cm. Neglecting thickness of the vanes, find ,velocity of flow at inlet- 1 velocity of flow at outlet, and- 2 .velocity of whirl at inlet- 3
An outward flow reaction turbine has inner and outer diameters of the -] 6 [
wheel has 1 m , and 2 m respectively. The water enters the vanes at an angle of 20velocity of flow at inlet, 20 and leaves the vanes radially. If the velocity of flow remain constant at 10 m/d and the speed of the wheel be 300 r.p.m., find the vane
. angles at inlet and outlet
An inward flow reaction turbine has external and internal wheel diameter -] 7 [
as 1 m and 0.5 m respectively. The water enters the wheel with a velocity of 30 m/s, at an angle of 10. The width of wheel at inlet and outlet is 150 mm and 300 mm, ; respectively. The vane angle is 0=90 at inlet and 25 at outlet. Determine the tangential velocity of runner at inlet, and- 1 absolute velocity of water at outlet- 2
An outward flow reaction turbine has internal and externa diameters of 2.4 -] 8 [
m and 3 m respectively. The turbine has a radial discharge of 6 cubic meters per second and is running at 200 r.p.m. The total head on the turbine is 40 m, and width ; of the wheel at inlet and outlet is 30 cm. Neglecting thickness of the vanes, find ,Velocity of flow at inlet- 1 Velocity of flow at outlet, and- 2 .Velocity of whirl at inlet- 3
An inward flow reaction turbine is working under a head of 25 meters and -] 9 [
running at 300 revolutions per minute. The of periphery of the wheel is 30 metres per second, and velocity of flow is 4 meters per second. If the hydraulic losses are 20% of the available head, and the discharge is radial. Take the ratio of wheel ; width to diameter is 25%, and overall efficiency is 85%. Determine ,The guide blade angle at inlet and the wheel angle at inlet- 1 ,The wheel dimensions and the shaft power developed in MW- 2 Flow ratio, speed ratio, unit power, unit speed, unit discharge, and specific - 3
. speed
An inward flow reaction turbine has tangential velocity of runner,. -] 10 [
velocity of flow and velocity of whirl at inlet as 30 m/s and 24 m/d, respectively. Assuming the discharge to be radial at outlet and hydraulic efficiency as 78%,
. determine: the total head on the turbine and the inlet vane angle
An inward flow reaction turbine, working under a head of 8 m has guide. -] 11 [
blade angle 25 and vane angle at inlet 105. Assuming the velocity of flow to be
. constant and radial discharge, determine hydraulic efficiency of the turbine
Find the mean diameter and blade angles at inlet and outlet of an inward. -] 12 [
: flow reaction turbine of the following particulars
A Francis turbine, working under a head of 14 m, has guide blade -] 15 [
angle of 20 and radial vanes at inlet. The ratio of inlet and outlet diameters is 3 to
- The velocity of flow of water at exit is 14 m/s. Assuming the velocity of flow to be constant, determine the peripheral velocity of water at inlet and the vand angle at . outlet
A Francis turbine, having an overall efficiency of 75%. is required -] 16 [
to give 132.4 kW, under a head of 9 m and at 120 r.p.m. The velocity of periphery of
the wheel and velocity of flow at inlet is 3.47^ โ H^ and 1.15^ โ H^ , respectively. If the
; hydraulic losses in the turbine are 20% of he available energy, find ,guide blade angle at inlet- 1 wheel vane angle at inlet, and- 2 .diameter of the wheel- 3
An inward mixed flow reaction turbine with radial discharge, is -] 17 [
supplied to develop 2580 kW under a head of 30 m, and with an overall efficiency of
82%. The peripheral velocity of the wheel is .30 โ 2 gH. If the wheel is to make 200
; r.p.m. and the hydraulic losses are 12%, determine ,discharge of the turbine- 1 ,guide blade angle- 2 vane angle at inlet, and- 3 .diameter of wheel at inlet- 4
A reaction turbine is supplied with 100 cubic meters of water per -] 18 [
second under an average head of 150 m. The runner diameter is 3.6 m at inlet and 2.4 m at outlet. Its inlet vane is 120. Assuming radial discharge at 15 m/s, breadth of wheel being constant, and hydraulic efficiency of 90%, find the power produced
. and the speed of the machine
A Kaplan reaction turbine operating under a net head of 20 m, -] 19 [
develops 36787.5 kW with an overall efficiency of 86%. The speed ratio is 2, and flow ratio is 0.60. The hub diameter of the wheel is 0.35 times the outside diameter
. of the wheel. Find the diameter and speed of the turbine
Find the operating speed and diameter of the runner, of a Kaplan -] 20 [
: turbine, having the following specifications Rated power = 11330.5 kW Average head = 4.3 m Overall efficiency = 90% : Assume ,diameter of runner boss 0.30 diameter of runner- 1 ,speed ratio = 2- 2
,flow ratio = 0.65- 3
A propeller turbine runner has an outer diameter of 4.5 m and an -] 21 [
inner diameter of 2.5 m and develops 20600 kW, when running at 140 r.p.m. under
. a head of 20 m. The hydraulic efficiency is 94% and overall efficiency is 80% . Find discharge through the turbine, and the guide blade angle at inlet
An inward flow reaction turbine is working under a head of 25 meters and- ] 22 [
running at 300 revolutions per minute. The of periphery of the wheel is 30 meter s per second, and velocity of flow is 4 meters per second. If the hydraulic losses are 20% of the available head, and the discharge is radial. Take the ratio of wheel ; width to diameter is 25%, and overall efficiency is 85%. Determine ,the guide blade angle at inlet, and the wheel angle at inlet- 1 ,the wheel dimensions, and the shaft power developed in MW- 2 flow ratio, speed ratio, unit power, unit speed, unit discharge, and specific - 3
. speed
An inward flow reaction turbine has external diameter of 60 cm. The - ] 23 [
guide blade angle at inlet is 22 (^) and the discharge is radial. The head of water over the turbine is 12 meters and velocity of flow through the runner is constant. If 8% ; of the area is blocked by runner vanes. Find ,Absolute velocity of water at inlet, assuming coefficient of velocity as 0.95- 1 Speed of runner in r.p.m., and discharge in liter/s, and- 2 ,ggi blade angles at inlet and outlet- 3 .%,The power developed in kW, and hydraulic efficiency- 4
A Kaplan reaction turbine develops 1471.5 kW, under a head of 6 m. The -] 24 [
turbine is set 2.5 m above the tail level. A vacuum gauge, instead at the turbine outlet, records a auction head 3.1 m. If the turbine efficiency is 85%, what will be
. he efficiency of draft tube, having inlet diameter of 3 m ************************************
