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A water turbine is a rotary machine that converts kinetic energy and potential energy of water into mechanical work. Water turbines were developed in the 19th century and were widely used for industrial power prior to electrical grids .
Hydropower (from Ancient Greek ὑδρο-, "water"), also known as water power or water energy, is the use of falling or fast-running water to produce electricity or to power machines. This is achieved by converting the gravitational potential or kinetic energy of a water source to produce power. [1] Hydropower is a method of sustainable energy ...
Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. The power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head.
A steam turbine with the case opened Humming of a small pneumatic turbine used in a German 1940s-vintage safety lamp. A turbine (/ ˈ t ɜːr b aɪ n / or / ˈ t ɜːr b ɪ n /) (from the Greek τύρβη, tyrbē, or Latin turbo, meaning vortex) [1] [2] is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work.
The Francis turbine is a type of water turbine. It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency. [1] The process of arriving at the modern Francis runner design took from 1848 to approximately 1920. [1]
The power coefficient [9] C P (= P/P wind) is the dimensionless ratio of the extractable power P to the kinetic power P wind available in the undistributed stream. [ citation needed ] It has a maximum value C P max = 16/27 = 0.593 (or 59.3%; however, coefficients of performance are usually expressed as a decimal, not a percentage).
A wheel power divided by the initial jet power, is the turbine efficiency, η = 4u(V i − u)/V i 2. It is zero for u = 0 and for u = V i. As the equations indicate, when a real Pelton wheel is working close to maximum efficiency, the fluid flows off the wheel with very little residual velocity. [11]
To derive the Turbine specific speed equation we first start with the Power formula for water then using proportionalities with η,ρ, and g being constant they can be removed. The power of the turbine is therefore only dependent on the head H and flow Q. = so . let: