| 摘要 |
An gas axial flow gas turbine comprises a turbine and a turbine exhaust section. The turbine comprises a turbine nozzle containing a low pressure turbine stage having an annular row of stator vanes (V2) followed in axial succession by an annular row of rotor blades (B2). The low pressure turbine stage is characterised by the following parameters: the ratio of vane aerofoil pitch to vane aerofoil axial width (P/W) at the root end of the vane aerofoil (V2) is in the region of 1.0 to 1.2, preferably about 1.12; the ratio of blade aerofoil pitch to blade aerofoil axial width (P/W)at the root end of the blade aerofoil (B2) is in the region of 0.6; the ratio of blade diameter at the tip end of the blade aerofoil to blade diameter at the root end of the blade aerofoil (blade tip/hub diameter ratio) is in the region of 1.6-1.8, preferably about 1.72; and the ratio of the axial length of the exhaust section to the blade aerofoil height (L/H) is no greater than a value in the region of 4:1, preferably 3:1. <??>These parameters are subject to a permitted variation of up to +/-10%, preferably up to +/-5%. Dimensions of example aerofoils are given and are scaleable to produce turbines of any chosen power. <IMAGE> <IMAGE> |
