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HYDRAULIC MACHINERYNAMA AHLI KUMPULAN :1. Muhammad Shahruzi Bin Mahadzir Df1500652. Muhammad Nur Aiman Bin Adnan Df1500453. Muhammad Nur Hafiz Bin Mahadi Df1500324. Mah Mudin Bin Amin Df1500365. Muhammad Amzar Bin Othman Df150012
NAMA PENSYARAH :Dr Mohd Ariff Bin Ahmad Nazri
FALKULTI KEJURUTERAAN AWAM DAN ALAM SEKITARBFC21103HIDRAULIK
SEMESTER 2 2015/2016
Turbines
Turbine is a hydraulic machine that utilises the energy of fluids to move other types of machineries.
A common use of turbine is in the hydroelectric power generation plant.
Classification Of TurbineBased on the hydraulic action at the inlet, turbines can be classified as: a) Impulse turbine (Pelton wheel or turbine) - derives its energy from
a jet of water exiting out of a nozzle and shooting at the blades of turbine.
b) Reaction turbine (Francis turbine or Kaplan turbine) - derives its power from the equal and opposite reactive power of fluid passing between its blades.
The basic and main difference between impulse and reaction turbine is that there is pressure change in the fluid as it passes through runner of reaction turbine.
Impulse Turbine
There is no pressure change in the runner.
First all pressure energy of water convert into the kinetic energy through a nozzle and generate a high speed jet of water.
The water jet strikes the blade of turbine and rotates it.
Reaction Turbine
■ In the reaction turbine there is pressure change of water when it passes through the rotor of turbine.
■ It uses kinetic energy as well as pressure energy to rotate the turbine. Due to this it is known as reaction turbine.
Impulse Turbine Reaction Turbine1. In impulse turbine only kinetic energy is used to rotate the turbine.
1. In reaction turbine both kinetic and pressure energy is used to rotate the turbine.
2. In this turbine water flow through the nozzle and strike the blades of turbine.
2. In this turbine water is guided by the guide blades to flow over the turbine.
3. All pressure energy of water converted into kinetic energy before striking the vanes.
3. In reaction turbine, there is no change in pressure energy of water before striking.
4. The pressure of the water remains unchanged and is equal to atmospheric pressure during process.
4. The pressure of water is reducing after passing through vanes.
5. Water may admitted over a part of circumference or over the whole circumference of the wheel of turbine.
5. Water may admitted over a part of circumference or over the whole circumference of the wheel of turbine.
6. In impulse turbine casing has no hydraulic function to perform because the jet is at atmospheric pressure. This casing serves only to prevent splashing of water.
6. Casing is absolutely necessary because the pressure at inlet of the turbine is much higher than the pressure at outlet. It is sealed from atmospheric pressure.
7. This turbine is most suitable for large head and lower flow rate. Pelton wheel is the example of this turbine.
7. This turbine is best suited for higher flow rate and lower head situation.
Classification Of TurbinesBased on the direction of flow through the runner, turbines can be classified as:a. Tangential flow turbine (Pelton wheel) b. Radial flow turbine (Francis turbine, Thomsen and Girard turbines)c. Axial flow turbine (Kaplan turbine)d. Mixed flow turbine (modern Francis turbine)
Tangential Flow TurbineWater turbines of this type :receive high-pressure water from single or multiple jets that either point at a tangent to the runnerIn each case the water must meet the bucket inlet with as little ‘shock’ as possible discharge tangentially so that the water falls to the bottom of the casingExample : Pelton Wheel
Radial Flow Turbine
turbines in which the water flows in radial direction. inward radial flow turbine : water flows from outwards to inwards
through the runner. outward radial flow turbine : water flows from inwards to outwards Example : Francis Turbine
Mixed Flow Turbine
Water flows radially into the runner Leaves out the runner axially The combination of axially flow and radially flow in the turbine is
known as mixed flow turbine Example : Francis Turbine
Axial Flow TurbineIf the water flows parallel to the axis of the of turbineRotation of runner will be transferred to the generator to produce electricityTypes of axial flow turbines:
1. Propeller turbine : vanes are not adjustable 2. Kaplan turbine : vanes are adjustable
Pelton Wheel (High head, Low Flow Rate)
Francis Turbine (Medium Head, Medium Flow Rate)
Kaplan Turbine ( Low Head, High Flow rate)
Head of Water, H High Head Turbine
- ( Pelton wheel, H > 250m)
Medium Head Turbine- ( Francis Turbine, 60m ≤ H ≤ 250m)
Low Head Turbine- ( Kaplan Turbine, H < 60m )
Specific Speed, Low specific speed turbine
- ( Pelton wheels, of 10 to 35 )
Medium specific speed turbine- ( Francis Turbine, of 60 to 400 )
High specific speed turbine- ( Kaplan turbine, of 300 to 1000 )
A pump is a Hydraulic machine which Supplies energy to fluid in certain operation
Mode of action conversion of mechanical energy hydraulic energy
Pump can be classifieda) Rotadynamic pumps : centrifugal pump and propellerb) Positive displacement pumps
Rotadynamic Pump Known as impeller
Fluids pumped into casing near the shaft of the
impeller
Vanes attached to spinning impeller:
a)increases the velocityb) Moves the fluid out
through an outlet
Centrifugal Pump Produce radial flow and mixed flow
according to the fluid path Converts rational energy A portion of the energy goes into
kinetic energy Fluid gains both velocity and pressure
while passing through the impeller
Propeller Pump
Consist of an impeller produces axial flow Relatively high discharge (flow rate) at a relative low head Pump up to 3 times more water Handling sewage from commercial, municipal and industrial
Positive Displacement Pump pumps operate by forcing a fixed volume of fluid from the inlet
pressure section of the pump into the discharge zone of the pump Positive-displacement pumps frequently are used in hydraulic systems
at pressures ranging up to 5000 psi provide a fixed displacement per revolution and, within mechanical
limitations, infinite pressure to move fluids Two types of positive displacement pump
a) Reciprocating pumpb) Rotary pump
Reciprocating Pump volume of liquid is drawn into the cylinder through the suction valve
on the intake stroke and is discharged under positive pressure through the outlet valves on the discharge stroke.
The discharge from a reciprocating pump is pulsating and changes only when the speed of the pump is changed.
This is because the intake is always a constant volume. Often an air chamber is connected on the discharge side of the pump
to provide a more even flow by evening out the pressure surges. Reciprocating pumps are often used for sludge and slurry.
Rotary Pump A rotary pump traps fluid in its closed casing and discharges a smooth
flow. They can handle almost any liquid that does not contain hard and abrasive solids, including viscous liquids
They are also simple in design and efficient in handling flow conditions that are usually considered to low for economic application of centrifuges
Power And Efficiency Of Pump Mechanical energy through the shaft and impeller is converted to fluid
energy Different between the total head of energy between the intake and
discharge Denoted as net head, H developed by pump Intake end (flow inlet) known as suction end Discharge (flow outlet) known as delivery end