| 摘要 |
A gas turbine with improved efficiency has at least one low pressure turbine stage, with rotary blades and stationary vanes, in combination with an exhaust section and is characterised by the following parameters: <SL> <LI>(i) the ratio of vane/blade tip to root diameter is in the region of 1.6-1.8, preferably 1.72; <LI>(ii) the ratio of vane pitch to vane axial width at root is in the region of 1.0 to 1.2; <LI>(iii) the ratio of blade pitch to blade axial width at root is in the region of 0.6, and <LI>(iv) the exhaust section has a ratio of axial length (ie the axial length of the exhaust from the final low-pressure stage to the back axial wall of the turbine) to blade height not greater than in the region of 4:1, preferably 3:1. </SL> The vane/blade dimensions are scalable and the above figures are subject to a permitted variation of up to Ò 10%, preferably Ò 5%. |
