The sustainable development of energy makes deep peaking a crucial part of thermal power generation technology.In order to an-alyze the flexibility modification capability of the boiler of supercritical coal-fired unit and the hydrodynamic safety characteristics of water wall system during deep peaking,for the structural characteristics of a 350 MW supercritical spiral coil boiler,the complex water wall sys-tem was divided into flow loops and pressure nodes based on the flow mesh system method,and a nonlinear calculation model for solving the hydrodynamic characteristics of a supercritical boiler was established by combining the three major conservation laws and the heat transfer equation.On the basis of the real furnace test,the actual heat absorption deviation distribution along the width of the furnace at 26.3％BMCR(92 MW)load was backpropagated,and the vapor temperature and pressure drop of the upper furnace exit calculated by the program were compared with the measured data of the real furnace to verify the reliability of the model.On the basis of the real furnace test study,the nodal pressure and loop mass flow rate distributions of the water wall,the trends of the outlet vapor temperature deviation and the wall temperature along the direction of the furnace height were studied and analyzed under 20％BMCR(70 MW)deep peaking load condition,and the calibration calculations were performed for the flow instability.Calculation results show that the supercritical spi-ral coil boiler in 20％BMCR deep peaking load operation,the total system pressure drop is 0.603 7 MPa,the maximum outlet steam tem-perature deviation of the upper hearth is 29.4℃,the maximum outer wall temperature is 381.1℃,and the maximum fin end temperature is 383.4℃,and the wall temperature and fin temperatures are all in the permissible temperature range of the material,which ensures safe and reliable hydrodynamics for 20％BMCR deep peaking load operation,and the flow stability is good.
deep peakingsupercritical boilerreal furnace testinghydrodynamic calculationflow instability
维普
万方数据
