Turgos operate in a head range where the Francis and Pelton overlap. While many large Turgo installations exist, they are also popular for small hydro where low cost is very important.
Like all turbines with nozzles, blockage by debris must be prevented for effective operation.
The Turgo turbine is an impulse type turbine; water does not change pressure as it moves through the turbine blades. The water's potential energy is converted to kinetic energy with a nozzle. The high speed water jet is then directed on the turbine blades which deflect and reverse the flow. The resulting impulse spins the turbine runner, imparting energy to the turbine shaft. Water exits with very little energy. Turgo runners may have an efficiency of over 90%
A Turgo runner looks like a Pelton runner split in half. For the same power, the Turgo runner is one half the diameters of the Pelton runner, and so twice the specific speed. The Turgo can handle a greater water flow than the Pelton because exiting water doesn't interfere with adjacent buckets.
The specific speed of Turgo runners is between the Francis and Pelton. Single or multiple nozzles can be used. Increasing the number of jets increases the specific speed of the runner by the square root of the number of jets (four jets yield twice the specific speed of one jet on the same turbine).
The turgo turbines supplied by our company are ranging from 50 to 250m in water head, 0.1 to 2MW in capacity and 0.35 to 1.5m in runner diameter. Their shaft arrangements are either vertical or horizontal and they may have single nozzle, twin or multi-nozzles. These units have their own structural peculiarities, satisfactory performances and economic.
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