Abstract:
Providing cooling within hollow blades such as high pressure turbine blades in a gas turbine engine is important to maintain these components within operational margins for the materials from which they are formed. Traditionally, coolant flows in hollow passages have been used along with impingement apertures towards a leading passage for cooling effectiveness. It is known that opposed undulations or ribs can create rotational vortices within the passage. By shaping shaped portions between the opposed undulations and possibly providing undulations upon these shaped portions themselves it is possible to generate stronger more powerful vortices within the passage. These vortices are coupled with the impingement orifices to create proportionally greater impingement jet flow and pressure and therefore cooling effectiveness within the leading passage.
Abstract:
An internal fluid cooling system for a gas turbine aerofoil (2) comprises a plurality of multi-pass cooling arrangements each of which consists of a serpentine passage (50,52,54 & 48,56,58) in the interior of the aerofoil (2). The cooling fluid—in particular air—is supplied to an inlet end (22,24) of each passage (50,52,54 & 48,56,58) and exhausted through a multiplicity of discharge holes (60,62,64,68) to provide tip, leading edge, trailing edge and surface film cooling. The inlet end (22) of a first serpentine passage (50,52,54) is positioned close to the leading edge (26) and flows rearwards while the inlet end (24) of the second serpentine passage (48,56,58) is positioned close to the trailing edge (28) and flows forwards. These serpentine passages are disposed side-by-side, one adjacent the pressure surface (14) and the other adjacent the suction surface (16) on opposite sides of a main load carrying member (30) which comprises a major part of the internal structure (30,36,38,40,42,44) of the aerofoil (2).
Abstract:
Providing cooling within hollow blades such as high pressure turbine blades in a gas turbine engine is important to maintain these components within operational margins for the materials from which they are formed. Traditionally, coolant flows in hollow passages have been used along with impingement apertures towards a leading passage for cooling effectiveness. It is known that opposed undulations or ribs can create rotational vortices within the passage. By shaping shaped portions between the opposed undulations and possibly providing undulations upon these shaped portions themselves it is possible to generate stronger more powerful vortices within the passage. These vortices are coupled with the impingement orifices to create proportionally greater impingement jet flow and pressure and therefore cooling effectiveness within the leading passage.
Abstract:
A rotor blade has a tip with an outer face including at least two channels which each extend to an outlet in the vicinity of the trailing edge. Accordingly, gas leakage around the tip must cross at least three walls, at least in the vicinity of the uncovered turning region near the trailing edge of the blade. Leakage gas entering the channels will tend to create a vortex and pass along the channel to the outlet.
Abstract:
An aerofoil 20 for a gas turbine engine includes a root portion 22, a tip portion 24 located radially outwardly of the root portion 22, leading and trailing edges 26, 28 extending between the root portion 22 and the tip portion 24 and an internal cooling passage 34. The aerofoil 20 includes a plurality of cooling fluid discharge apertures 36 extending between the root portion 22 and the tip portion 24 in a trailing edge region 28a to discharge cooling fluid from the internal cooling passage 34 to an outer surface 31 of the aerofoil in the trailing edge region 28a and thereby provide a cooling film in the trailing edge region 28a. The cooling fluid discharge apertures 36 are arranged so that the flow rate of the cooling fluid discharged from the internal cooling passage 34 to the outer surface trailing edge region 28a varies between the root portion 22 and the tip portion 24.
Abstract:
A rotor blade has a tip with an outer face including at least two channels which each extend to an outlet in the vicinity of the trailing edge. Accordingly, gas leakage around the tip must cross at least three walls, at least in the vicinity of the uncovered turning region near the trailing edge of the blade. Leakage gas entering the channels will tend to create a vortex and pass along the channel to the outlet.
Abstract:
Cooling arrangements for blades, and in particular turbine blades utilizing gas turbine engines include impingement apertures with impingement jets, which improve cooling efficiency. By providing a leading passage, which is divided at least into a lower section and an upper section, the lower section can have a wall, which is solid for structural integrity while an upper section has impingement apertures for greater cooling efficiency.
Abstract:
Cooling with regard to high-pressure turbine platforms is important in order to maintain gas turbine engine efficiency. Cottage Roof dampers located below junction gaps between adjacent platforms have been used but tend to present spent coolant flow at a high angle relative to hot gas flows about the aerofoil blades. The present arrangement has the junction gap angled such that the emergent coolant flow remains adjacent to the suction side to create a coolant film lingering above that suction side of the platform.
Abstract:
An aerofoil 20 for a gas turbine engine includes a root portion 22, a tip portion 24 located radially outwardly of the root portion 22, leading and trailing edges 26, 28 extending between the root portion 22 and the tip portion 24 and an internal cooling passage 34. The aerofoil 20 includes a plurality of cooling fluid discharge apertures 36 extending between the root portion 22 and the tip portion 24 in a trailing edge region 28a to discharge cooling fluid from the internal cooling passage 34 to an outer surface 31 of the aerofoil in the trailing edge region 28a and thereby provide a cooling film in the trailing edge region 28a. The cooling fluid discharge apertures 36 are arranged so that the flow rate of the cooling fluid discharged from the internal cooling passage 34 to the outer surface trailing edge region 28a varies between the root portion 22 and the tip portion 24.
Abstract:
An internal fluid cooling system for a gas turbine aerofoil comprises a plurality of multi-pass cooling arrangements each of which consists of a serpentine passage in the interior of the aerofoil. The cooling fluid—in particular air—is supplied to an inlet end of each passage and exhausted through a multiplicity of discharge holes to provide tip, leading edge, trailing edge and surface film cooling. The inlet end of a first serpentine passage is positioned close to the leading edge and flows rearwards while the inlet end of the second serpentine passage is positioned close to the trailing edge and flows forwards. These serpentine passages are disposed side-by-side, one adjacent the pressure surface and the other adjacent the suction surface on opposite sides of a main load carrying member which comprises a major part of the internal structure of the aerofoil.