Utility Boiler Pulverized Coal Concentration Were Studied

With the progress in generating electricity technology, in power station boiler circulates, the control of the coal powder concentration and speed in each air pipe is more and more important for circulating to the safety and economies of the boiler. So it is very important that find a kind of accurate, dependable on-line method for measuring coal powder concentration. The method can raise the stability, economy and reliability of boiler combustion . In this paper ,author verified the target flowmeter can be used for the measuring concentration of Gas-particle two phase flow by the contrast between numerical calculation and experiments . In the way of numerical calculation, a Discrete phase model of mathematical software FLUENT has been used to imitate the flow field where Gas-particle two phase flow impact the piece of target in target flowmeter. The SIMPLE calculate method was used to calculate press and velocity between discreted mesh. This calculation project include seven kinds of target, pressure and speed was calculated in every target flowmeter model. Though comparing stress on seven kinds of target at different concentration of Gas-particle two phase flow in the piping, three kinds of target which were sensitive to variety of coal powder concentration were selected. Then author compared stress on every target at different in the piping, and put forward the globose target flowmeter have two advantage in measuring concentration of Gas-particle two phase flow. The first advantage is the least variety of stress on globose target in three kinds of target when wind velocity changed. The second advantage is that globose targe is the most sensitive to variety of coal powder concentrationIn the experiment, a testing piping system for coal powder and air two phase flow was built in laboratory. Experiment adopt disk target and spherical target two kinds of target. Both the test datas of two kinds of target expressed that the stress on target has visible rise when putting the coal powder in pipe and keep the same wind velocity. This phenomenon was verifying the feasibility that the method of target flowmeter can measure the concentration of sparse Gas-particle two phase flows. The stress on the disk...