300MW Unit Steam Institutions With Optimum Design And Operation Test Research

In this thesis, nozzle with comprehensive governing valves are optimized design and into steam parameters optimization analysis, this paper sums up the optimized design of the relationship between and nozzle, the steam institutions with the optimization of the given general methods and rules.By measuring the governing valves, getting the flow characteristic curve of a single governing valves; Through the calculation of the degree of overlap between governing valves, adjust the governing valves are overlapping degree, reduce the tone of throttling losses, improve the efficiency of steam distribution.In the comprehensive support unit is with steam institution characteristics and operation parameters, under the premise of optimizing the flow area of the nozzle, and to optimize the leaf type nozzle blade design, improve the efficiency of the level adjustment. Combined with the optimization design of the nozzle group, analyzes derived the best inlet parameters.Through to survey and draw the intrinsical nozzle block and guiding blade, depend on experimental study and numerical calculation to optimize the nozzle block of flow path area. Retrofit unit of rated conditions work in three-valve status. Analysis and calculation the loss of governing valve throttle for before and after the retrofit, and due to working angle of movable vane changing lead to loss of goveming valve throttle, and changing of section inlet vapour level. The comprehensive comparison, under the condition of high pressure cylinder rated the efficiency will be increased by 1.2%. After the retrofit of the test after test, the actual the flow through consistent with design flow, high pressure cylinder efficiency increased by 1.4%, and exceeded the design effect.The head part of the guide blade was optimized,the curve connection was more smoothly.The isoenthropic effeciency coulde be improved 0.2% in the guide blade.After the optimization design of the nozzle block,the results can be full played by experimental optimization.Through improving the main steam pressure,the cycle efficience was improved obverously. The net coal comsumption can be reduced 5g/kWh on low load operation region.