Numerrical Simulation And Expermental Study Of Aerodynamic Operating Conditions In A Small Agricutural Waste Incinerator

With the rapid development of China’s economy,the living standards of the people are improving day by day,and the amount of domestic waste produced by each person has increased sharply.The development of rural areas has also been significantly improved,so that rural solid wastes increase at a rate of 10% every year.How to deal with these solid wastes is a difficult problem faced by our country.The previous landfill method has increasingly shown that the disadvantages outweigh the advantages.Realize the resource utilization of these solid wastes and do not let them become useless things to destroy the environment.Municipal solid waste incineration has become the first choice to deal with these solid wastes.In view of the low combustion efficiency of the small agricultural waste incinerator,this paper proposes to design a reasonable furnace arch structure to burn out the fuel in the furnace.The main research contents and conclusions include:1.At present,there are similarities between municipal solid waste boilers and industrial coal-fired boilers.In view of the unreasonable configuration of its feeding device,front and rear arch and ash cleaning device,some problems are analyzed,and a reasonable transformation scheme is put forward.Lower the front arch pressure and raise the rear arch to increase the full mixing of combustible gas and oxygen in the flue gas to reduce the heat loss of incomplete combustion.2.Because there are six factors affecting the aerodynamic field in the municipal solid waste furnace,and then arrange the experiment according to the orthogonal experiment,eight typical working conditions are obtained.The flow field distribution of the municipal solid waste incinerator is simulated by fluent,and the simulated velocity vector diagram and flow function isoline map are analyzed.It is concluded that the best condition is under condition 1(front arch inclination 45,front arch height600 mm,rear arch outlet height 400mm).It is seen that the air flow distribution in the whole furnace arch area is uniform,and the high temperature flue gas is an ideal "L" type flow.The dimensionless criterion of ideal furnace arch structure : h / L = 0.333,h/ L = 0.120,the inclination angle of front arch is 45,the rear arch is horizontal arch,and the front and rear arch adopt full cover structure.3.In the cold state test,the hot wire anemometer with spherical wind direction probe will be used to measure the uniformity and turbulence of the transverse air distribution of the grate,and the magnitude and direction of the air velocity at each measuring point in the furnace.The analysis shows that the more suitable front and rear arch momentum flow ratio is in the range of 1 2.115.40,the turbulence value distribution in the area of l/L=0.25～0.60 is larger,and the maximum value appears near the 10 th measuring hole,but the value behind the furnace is smaller.