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Micro hydro is a type of hydroelectric power that typically produces from 5 kW to 100 kW of electricity using the natural flow of water. Installations below 5 kW are called pico hydro . [ 1 ] These installations can provide power to an isolated home or small community, or are sometimes connected to electric power networks, particularly where ...
Cross-flow turbine: Also known as Banki-Mitchell or Ossberger turbines, these devices are used for a large range of hydraulic heads (from 2 to 100 meters) and flow rates (from 0.03 to 20 m 3 /s), but are more efficient for low heads and low power outputs. They are considered "impulse" turbines, since they get energy from water by reducing its ...
A hydropower resource can be evaluated by its available power. Power is a function of the hydraulic head and volumetric flow rate. The head is the energy per unit weight (or unit mass) of water. [5] The static head is proportional to the difference in height through which the water falls. Dynamic head is related to the velocity of moving water.
For example, a low-head hydro power plant with hydrostatic head of few meters to few tens of meters can be classified either as an SHP or an LHP. [30] The other distinction between SHP and LHP is the degree of the water flow regulation: a typical SHP primarily uses the natural water discharge with very little regulation in comparison to an LHP.
In most contexts a mention of rate of fluid flow is likely to refer to the volumetric rate. In hydrometry, the volumetric flow rate is known as discharge. Volumetric flow rate should not be confused with volumetric flux, as defined by Darcy's law and represented by the symbol q, with units of m 3 /(m 2 ·s), that is, m·s −1. The integration ...
A wicket gate, or guide vane, is a ring of gates (or vanes) surrounding a water turbine which control the flow of water entering it; varying the aperture between them manages the rate of the turbine's spin, and thereby the amount of electricity generated.
Specific speed N s, is used to characterize turbomachinery speed. [1] Common commercial and industrial practices use dimensioned versions which are of equal utility. Specific speed is most commonly used in pump applications to define the suction specific speed —a quasi non-dimensional number that categorizes pump impellers as to their type and proportions.
By Newton's second and third laws, the force F imposed by the jet on the runner is equal but opposite to the rate of momentum change of the fluid, so F = −m(V f − V i)/t = −ρQ[(−V i + 2u) − V i] = −ρQ(−2V i + 2u) = 2ρQ(V i − u), where ρ is the density, and Q is the volume rate of flow of fluid.