Hydraulic Turbine

Duct

A channel or tube for conveying

Penstock

A closed conduit or pipe for conducting water to the powerhouse

Dam

A concrete structure that impounds water for irrigation and hydropower purposes

Motor

A device that converts electrical energy tomechanical energy

Generator

A device that converts mechanical energy to electrical energy.

Jet

A fluid stream issuing from an oriface or nozzle

Reservoir

A large natural or artificial enclosure used as a source of water supply in a hydraulic system

Propeller

A mechanical device for propelling a boat or aircraft, consisting of a revolving shaft with two or more broad, angled blades attached to it.

Brake Nozzle

A nozzle directed at the back of the buckets, which is opened when there is a need to slow down or stop the turbine

Cavitation

A phenomenon which occurs when the pressure at a point in a hydraulic system is lowered below the vapor pressure of the oil in the system

Turbine

A rotary engine that converts the energy of a moving stream of water, steam or gas into mechanical energy

Runner

A rotating circular disc on the periphery of which buckets are mounted with equal spacing between them

Sluice Gate

A sliding gate used to control the flow of water

Scroll Casing

A spiral casing with a descreasing area to make sure that water flows into the central portion of the Kaplan turbine at uniform velocity

Wicket Gates

Adjustable elements that control the flow of water from the scroll case into the turbine passage

Pentrough

An open usually planked or boarded trough or tank from which water falls onto a waterwheel

Buckets

Cups or bowls attached tot he runner which take the impact of water from the nozzle causing the runner to rotate

Small Hydropower

Facilities that have a capacity of 100 KW to 30 Megawatts

Large Hydropower

Facilities that have a capacity of more than 30 Megawatts

Slit Sluice

Is a chamber that collects the mud and through which the mud is discharged

Draft Tube

Is a conically shaped conduit attached to the turbine discharge.

Hydraulic Turbine

Is a prime mover that converts the kinetic energy and potential energy of flowing water into mechanical power for the purpose of driving an electrical generator or other machinery

Kaplan Turbine

Is a propeller type water turbine with theadjjstable blades which work in reverse

Forebay

Is a small reservoir where water is temporarily stored

Pelton Turbine

Is a tangential flow impulse turbine that uses double curved buckets to capture the jet of water. It is primarily used for high heads

Francis Turbine

Is an inward flow reaction turbine having a radial discharge at outlet

Hydroelectricity

Is electricity produced from hydropower

Nozzle

Is provided at end of penstock and its main function is to increase the velocity or the water and to direct it to the buckets at the turbine

Spear

Is provided within the pen stock and its main function are to increase and decrease the amount and speed of water entering the turbine

Maximum Head

Is the gross head difference in elevation between the maximum forebay level without surcharge and the tailraxe level without spillway discharge

Design Head

Is the net head at which peak efficiency is desired. This head determines the basic dimensions of the turbine and therefore of the power plant.

Minimum Head

Is the net head resulting from the difference in elevation between the minimum forebay level and the tailrace level

Guide Mechanism

It consists of a circular wheel all-round the runner of the turbine. The stationary guide vanes are fixed on the guide wheel

Overall Efficiency

It is the ratio of the power available at the turbine shaft to the power available from the jet

Mechanical Efficiency

It is the ratio of the power available at turbine shaft to the power available at turbine runner

Hydraulic Efficiency

It is the ratio of the power developed by runner to the power supplied at the inlet of the turbine

Volumetric efficiency

It is the ratio of volume of water actually striking the runner to the total water supplied by the jet to the turbine

Turgo Turbine

Known as a Half Pelton Turbine, it uses a spoon shaped blades to capture the jet of water

Shaft Seal

Prevent water leakage between main shaft and head cover

Deflectors

Serves to bend the jet away from the runner at reducer loads to avoid a high speed increase

Head Cover

Supports the weights fo the guide vanes and confine the vibrations and unnecessary movements of the wicket gatesy

Splitter

The dividing wall which seperates each bucket of a pelton turbine into two symmetrical parts

Tail Race

The downstream channel that carries water away from a dam or powerhouse

Guide Bearing

The function of the turbine guide bearing is to resist the mechanical imbalance and hydraulic side loads from the turbine runner thereby maintaining the turbine runner in its centered position in the runner seals

Blade

The individual component responsible for extracting energy from the velocity of the water jet and uses it to do mechanical work on a rotating output shaft

Braking Jet

The jet of water produced by the break nozzle

Hub

The part of tge runner to which blades are mounted

Hydropower

The process of generating electricity by capturing the potential energy of falling water through the use of a water wheel

Efficiency

The ratio of the useful work performed by a machine or process to the total energy expended or heat taken in

Turbine Shaft

The rotating element, usually circular in cross section, which is used to transmit power from the turbine runner to the generator shaft and generator rotor

Runaway Speed

The speed at full flow, and no shaft load.

Specific Speed

The speed at which the turbine will run when developing one unit power under a unit head

Stator

The stationary part of the rotary system, found in eectric generators and electric motors. Its main purpose is to keep the field aligned.

Spillway

The structure or portion of a larger structure that is used to release excess water over or around a dam

Tail water

The water level downstream of the powerhouse or dam

Head Water

Water level at the supply reservoir

Vane

a broad blade attached to a rotating axis or wheel that pushes or is pushed by wind or water and forms part of a machine or device such as a windmill, propeller, or turbine.

Water wheel

a large wheel driven by flowing water, used to work machinery or to raise water to a higher level.

vortex

a mass of whirling fluid or air, especially a whirlpool or whirlwind.

Waterway

a river, canal, or other route for travel by water.

Affinity Laws

allow the output of a turbine to be predicted based on model tests

Axis

an imaginary line about which a body rotates

Trash Rack

is a screen which prevents the leaves, branches and other water contaminants to enter into the penstock.

Surge Chamber

is a standpipe connected to the atmosphere and attached to the penstock so that the water will be at atmospheric pressure.

Micro Hydropower

plant has a capacity of up to 100 KW