Abstract: Apparatus (10) for generating waves in a swimming pool comprises a plurality of wave generating chambers (11) each communicating with the pool through a below-the-water passageway (15) and having a closed upper portion (13) extending above the quiescent water level of the pool, each said upper portion (13) having first passageway means (16) connected via first fluid flow control means (17) to a pneumatic wave-generating medium (18) and second passageway means (19) connected via second fluid flow control means (20) to an aqueous wave generating medium (21), and operating means (30) connected to said first and second fluid flow control means (17, 20), said operating means (30) being arranged, in one mode, to cause intermitent delivery of said pneumatic wave-generating medium (18) to one of said chambers (11) to create a first wave-forming effect while simultaneously blocking delivery of said aqueous wave-generating medium (18) to said one chamber (11) and, in another mode, to cause delivery of said aqueous wave

Abstract: The present invention relates to combustion apparatus for gas turbine engines.An annular combustion chamber of a gas turbine engine comprises an upstream wall formed from a single metal skin. The upstream wall has a plurality of equi-spaced apertures, and a convergent/divergent pot is positioned coaxially with each aperture and extends in an upstream direction therefrom. Each convergent/divergent pot has a radial swirler assembly positioned a its upstream end to supply air into the convergent/divergent pot. A fuel injector is aligned with each convergent/divergent pot and radial swirler assembly to supply fuel into the convergent/divergent pot. A plurality of annular air scoops extend in an upstream direction from the upstream wall, and each annular air scoop is positioned coaxially around a convergent/divergent pot to supply air to the radial swirler assembly. The downstream end of each convergent/divergent pot has apertures for supplying cooling air over the downstream face of the upstream wall.