Exergy Analysis Of Thermal Systerm For PWR Nuclear Power Plant

After several years of development,the status of nuclear power is more and more important in China's power industry.Although nuclear energy is not only a unit of high energy,and a huge amount of storage,but we still have to study the problem of energy consumption of nuclear power.Energy analysis method can diagnose scientifically the weak part of the whole device,and guide the exploration the right measures of energy-saving,which is the purpose of analysis and calculation of the thermodynamic system of PWR nuclear unit based on energy analysis method.The first step: after detailed understanding of working principle of nuclear power unit thermal system and based on graph principle thermal system of nuclear power group,the research object is generally defined as the six main body of control: reactor,steam generator reheater,heat recovery system,steam turbine,condenser.When starting doing energy analysis and calculation of nuclear motor group for thermal system of the second circuit,the secondary loop thermal systems are detailed divided into 30 small control volume and 60 shares of energy flow.According to the known parameters of nuclear power generating units,the calculation program is written using MATLAB software program based on the energy analysis method.The second step: firstly,this paper does the calculation and analysis of nuclear motor group in standard conditions using energy analysis method,then respectively on the nuclear power group with different design conditions(90%THA,70%THA)for energy analysis and calculationt.Then this paper gets each equipment of energy efficiency and of energy loss coefficient in the three conditions.Secondly,this paper draws comparison chart of energy efficiency and energy loss coefficient based on the computational results of the three conditions.Finally,the distribution of each equipment of energy efficiency and of energy loss coefficient can be known through the graph analysis.Through the comparative analysis,the conclusion is: the reactors of energy loss is the biggest in the whole thermal system of the pressure water reactor nuclear power plant,accounting for about half of the total of energy of system,this part of energy loss can be reduced by reducing the loss of nuclear fission process and improving the average temperature of the reactor;The energy loss of steam turbine is second just under the reactor,those energy loss is mainly due to irreversible loss caused by gas expansion acting and thesteam turbine through flow part of the friction coefficient of dissipation.Thus the main measures of reducing energy loss of steam turbine is optimizing the design of steam turbine flow path,reducing the friction loss in the process of steam flow.