The Investigation Of Flow In An Induced Leaky Pipe

In the project, the environment often need negative pressure. The environment of negative pressure is usually generated by the function of induced pipe. If there is a leak on the induced pipe, the environment of negative pressure will be influenced and the negative pressure cannot meet the requirement. The LF furnace is an example. As there is a leak at the joint of induced pipe and de-dust duct, the distribution of the negative pressure of furnace can not meet the requirement, lots of soot get out from the leak between the electrode and the cover and it takes so much pollution to working environment. To investigate the flow in the induced leaky pipe, it can make the guide for the process of design, operation and maintenance of the working environment of negative pressure and it can also offer some reference for the optimization of the working environment of LF furnace.First, we build the experimental equipment of the leaky induced pipe, and get the pressure data and flow quantity data under different leak length and resistant characteristic of the pipe in experiment. By analyzing the relation of leak length, loss of negative pressure and distribution of the flow quantity in the pipe, the conclusion is that when resistant characteristic of the pipe is constant, as the leak length is increased, the negative pressure of the pipe fits exponential decay and loss of the negative pressure between the two side of the leak become bigger and the flow quantity on the right side of the pipe also fits exponential decay. In order to build the non-dimension relation of the leak length, loss of negative pressure and flow quantity of the pipe, the non-dimension parameter Cp (the coefficient of pressure-difference) is used. As theδ/D(leak length/diameter of the pipe ) is increased, the Cp presents an increased trend in each experiment. The data from each experiment fit an exponential line, that means the non-dimension relation between Cp andδ/D is a common rule in physical phenomenon of leaky induced pipe.Then, in order to broaden the investigated scope, the numerical investigation about the induced leaky pipe have been done. Building the physical model and the mathematic model ( k -εtwo-equation model, non-structural meshing method) and running the simulation under different leak length and different negative pressure boundary, the mathematic model is proved to fit for the physical phenomenon of leaky induced pipe...