Particle filter in gas turbine aerofoil internal air system

摘要

An aerofoil has a cooling gap 42 adjacent its internal surface formed by a V shaped liner insert 14 supported on pedestals 26. Air entering the aerofoil volume 12 is divided: passing through aperture 17 forming impingement cooling jets into chamber 38 and thence through effusion holes 36; passing through impingement cooling holes 45 in the liner panels 14a,b; the remainder entering gap 42 through apertures 50 into a plenum 46 formed by pressing the insert panel at the opposite end of the aerofoil to the air entry and through discriminating slot 44. The slot 44 is formed on two sides of the plenum by L shaped formations 52, the plenum being closed on the other two sides. Gap f therefore forms a screening aperture such that particles collect in and are discharged from the plenum through aperture 54.