A diffuser for use in apparatus for extracting energy from flowing fluids

摘要

This discloses a diffuser 10 for use in apparatus for extracting energy from flowing liquids. The diffuser 10 comprises a flow passage having an inlet 17 and an outlet 18 and a side wall or walls 14 between the inlet 17 and the outlet 18. The cross sectional area of the flow passage initially decreases inward from the inlet 17 to a constricted region between the inlet 17 and the outlet 18 and from there increases towards the outlet 18. The side wall or walls 14 are formed by a series of aerofoil section members 15 arranged in series between the inlet 17 and the outlet 18 such that other than at the inlet 17 and outlet 18, the trailing portion of one member is adjacent to the leading portion of the immediately adjacent trailing member and defines a gap or slot 29. Thus a number of gaps or slots 29 are provided between the inlet 17 and the outlet 18 through which fluid from outside the diffuser can pass into the flow passage.