ECONOMY INCREASE OF TURBOSET FLOW UNIT
Rubrics: MECHANICAL ENGINEERING AND TRANSPORT
Authors:
Type:
Article
Pages:
from 38
to 44
Status:
Published
Received:
29.12.2015
Accepted:
29.12.2015
Published:
29.12.2015
Language:
Russian
Keywords:
steam turbine, gas turbine, peripheral seal, impeller, band.
Abstract (English):
At present time a considerable part of installed facilities of steam – and gasturbine units exhausted the body resources in connection with that their modernization is an urgent problem. The effectiveness increase in the work of a flow part in turbine units can be achieved at the expense of peripheral leakage decrease in bandless and banded stages of steam and gas turbines. In banded stages it can be achieved due to the choice of optimum value in the peripheral overlap of turbine rotor blades. In the BSTU there was obtained a dependence allowing the approximate definition of the optimum value for the overlap. At the same time the design of peripheral honeycomb seal with variable geometry allowing the operation with increased gaps in vibrating dangerous modes (start and stop) and in nominal conditions – with reduced gaps that gives the decrease of operation heat leakage about 30% in comparison with a basic design is offered. For bandless stages on the outer outline of an impeller the spiral profile groove manufacturing is of-fered for the effect of flow blocking at periphery. In the BSTU on the test air benches it was established that at the optimum angle of spiral profile groove slope equal to 150 to the plane of the impeller rotation the efficiency increment for the stage of an average fanning is equal to about 1% in comparison with the variant of a smooth overlap. For the purpose of stage operation reliability increase at economy conservation there is offered a creation of the hollow chamber with 2…3mm depth in the middle part of the blade exterior cross section. The application of variants developed for the flow part modernization in turbomachines should contribute to effectiveness and reliability increase of powergenerating units and ensure the ecological characteristics improvement in plants at the expense of their vibro-acoustic activity decrease.
At present time a considerable part of installed facilities of steam – and gasturbine units exhausted the body resources in connection with that their modernization is an urgent problem. The effectiveness increase in the work of a flow part in turbine units can be achieved at the expense of peripheral leakage decrease in bandless and banded stages of steam and gas turbines. In banded stages it can be achieved due to the choice of optimum value in the peripheral overlap of turbine rotor blades. In the BSTU there was obtained a dependence allowing the approximate definition of the optimum value for the overlap. At the same time the design of peripheral honeycomb seal with variable geometry allowing the operation with increased gaps in vibrating dangerous modes (start and stop) and in nominal conditions – with reduced gaps that gives the decrease of operation heat leakage about 30% in comparison with a basic design is offered. For bandless stages on the outer outline of an impeller the spiral profile groove manufacturing is of-fered for the effect of flow blocking at periphery. In the BSTU on the test air benches it was established that at the optimum angle of spiral profile groove slope equal to 150 to the plane of the impeller rotation the efficiency increment for the stage of an average fanning is equal to about 1% in comparison with the variant of a smooth overlap. For the purpose of stage operation reliability increase at economy conservation there is offered a creation of the hollow chamber with 2…3mm depth in the middle part of the blade exterior cross section. The application of variants developed for the flow part modernization in turbomachines should contribute to effectiveness and reliability increase of powergenerating units and ensure the ecological characteristics improvement in plants at the expense of their vibro-acoustic activity decrease.
Keywords:
steam turbine, gas turbine, peripheral seal, impeller, band.
steam turbine, gas turbine, peripheral seal, impeller, band.
1. Gogolev, I.G., Stages and Suckers Aerodynamics of Heat Turbines/ I.G. Gogolev, A.M. Drokonov. - Bryansk: Grany, 1995. - pp. 258.
