Impulse turbine for use in bi-directional flows

Abstract

A bi-directional flow impulse type turbine arrangement (120) for use with a bi-directional reversing flow (F, F1, F2), and in particular for use with an oscillating water column power plant (110). The turbine arrangement (120) has a rotor (120), and first and second sets of guide vanes (140, 142) located on an opposite axial sides of the rotor (132) for directing the bi-directional reversing flow(F, F1, F2) to and from the rotor (132). The guide vanes (140, 142) are disposed at a greater radius (Rv) and radially offset (Ro) from the rotor blades (136). The turbine arrangement further comprises first and second annular ducts (146) disposed respectively between the first and second sets of guide vanes (140, 142) and the rotor (132) for directing fluid from the guide vanes (140, 142) to therotor blades (136). In addition, and in other aspects of the invention, the vanes (144) and rotor blades (136) have a novel profile, with in particular the vanes (144) having a profile to maintain a constant flow passage (Fp) between the vanes (144) over a turning section (164) of the vanes (144), and the rotor blades (136) of the rotor (132) having a higher turning angle (2alpha), and producing a non-axial outlet downstream flow. The turbine (120) may also in another aspect incorporate vanes (144) with a slot (190) and a boundary layer blowing arrangement to re-energise and improve the reverse flow over the vanes (144).

Description

technical field [0001] The present invention relates to turbine pack arrangements operable with bidirectional flow, and in particular to impulse turbine arrangements operable with bidirectional flow. More particularly, and preferably, it relates to a turbine arrangement for use in a vibrating water column power plant to generate electricity from wave forces. The turbine arrangement may additionally be used in the field of renewable power generation, or even more generally in other turbine applications. Background technique [0002] Generators using the power of vibrating water columns have been around for at least several decades. Typically, these generators comprise a very large chamber comprising: a first opening below potential water level; and a second opening to atmosphere via a turbine. As the crests and troughs of the waves reach the chamber, the level of the water column within the chamber rises and falls periodically, thereby alternately forcing the air in the cha...

AI Technical Summary

Problems solved by technology

[0007] Therefore, it is desirable to provide an alternative and provide an improved impingement turbine device that can operate from reverse bi-directional flow, such as pumped by a vibrating water column, and that provides solutions when flow through the impingement turbine A solution to the above problem of cyclically reversed time, overall inefficiency

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