Design And Experimental Study On Ventilation Modle Of Half-speed Turbo-generator In CAP1400 Nuclear Power

As a sub-topic of a national major project “large-scale half-speed turbo-generator and key technology research”,the ventilation experiment of half-speed turbo-generator in CAP1400 nuclear power has been studied.The purpose of the study is to ensure the safe and reliable operation of the generator through the ventilation cooling technology research and structural optimization on the basis of successful experience in running product design.Firstly,similarity analysis and equivalence analysis of the ventilation model have been finished.The air flow can be regarded as incompressible and steady flow based on similarity theory in the model.The ventilation system of the model is equivalent to the one of the real machine,and it can model the generator airway structure and the air flow characteristics effectively.Secondly,the ventilation simulation and the structural design of the model have been done.The ventilation net models of multiple structure schemes have been established by using Flowmaster software.Through the analysis of the result the rotor is designed with seven different sub-slot ventilation structures finally.Five of these seven structures are axial and radial ventilation,and the other two use radial ventilation.The stator uses the same structure as the real generator that is five-in-six-out ventilation structure.Because of the symmetrical character,the ventilation model is designed in semi-axial length.At last,the multi-program experiment of half-speed turbo-generator ventilation model in CAP1400 nuclear power has been studied.The rotor experiments were carried out by changing the number of rotor vents,pitch and the vent diameter,and then the best scheme was determined to finish the full machine experiment from several ventilation structures.The experiment data reflect the air flow characteristics and the deviation between test value and design value of the ventilation system directly,and predict the cooling effect of the generator.The experiment supplies the basis for the design of the generator ventilation system,and it will provide guidance for the choice of turbo-generator cooling method.