The Flow Characteristics Study Of Working Medium In The Water Wall Tube Of 600MW Supercritical W-shaped Flame Boiler

Supercritical and ultra supercritical generating sets have these advantages that less fuel consumption per unit of electricity, high power generation efficiency, high degree of automation, high speed of starting and stopping, sliding pressure operation and other advantages, it’s a kind of energy-saving, efficient, clean generating sets which is the trend of the development of generating sets in the future. In the supercritical boiler operation, there are various factors affecting the safety of the boiler, such as uneven distribution of temperature and velocity field inside the furnace, instability flowing of working medium in the boiler water wall tube, the negligence in the manufacturing installation process of heating surface of boiler water wall, etc., the flow characteristics of working medium in the supercritical boiler water wall tube is very important for the safety of supercritical boiler heating surface. Therefore, the research of the flow characteristics of working medium in the supercritical boiler water wall tube has very important significance.The paper take a certain power plant of 1900t/h supercritical w-shaped flame boiler as the research object, based on the two-phase flow model, calculate the flow characteristics of boiler water wall tube combining with the boiler unit hydrodynamic calculation method, and according to the calculation results the paper analyzes the influence of the mass velocity of boiler feed water, the temperature of the working medium in the water wall entrance (the owe enthalpy of entry working medium), water wall thermal load deviation to the boiler water wall tube working medium flow characteristics from the aspects of flow compensation characteristics of the working medium in the boiler water wall tube and so on. Analyzes the reasons of a series of tube burst and deformation situations of boiler water wall tube what appeared in the actual running of the 1900t/h supercritical w-shaped flame boiler according to the flow characteristics of working medium in the supercritical boiler water wall tube, tube wall temperature of the boiler water wall tube, the thermal stress of boiler water wall tube, then put forward the corresponding improvement measures from two aspects of boiler equipments and boiler combustion adjustment according to the specific reasons of tube burst and deformation situations of boiler water wall tube.