The Structure Research And Flow Field Analysis Of Dust Sucking Mouth Based On Sucking Performance

Vacuum sweeper vehicle is a kind of new road sweeping vehicle which applies minus air pressure. Dust sucking mouth is one of its key parts and decides dust sucking efficiency, air resistance and work reliability.There are three types of road sweeping vehicle in domestic. They include the combination of sucking and sweeping vehicle, only sucking vehicle and only sweeping vehicle. At present ,the first kind dominates the domestic market, but the vacuum sweeping vehicle is becoming popular because of its good performance in some special working condition. So the vacuum sweeping vehicle is an important development direction. This paper analyzed physical character of working material as air and dust particles, the principle of air flowing and the force interaction between air and dust particles. It explained the particle pick-up principle from the angle of hydrodynamics. The principle is that solid particles collide with each other under the effect of air flow and the wallop caused the pick-up of dust particles. It computerized the pick-up speed of rock, coal powder, cement, iron powder, iron piece, iron mineral, which supplies academic basis for dust sucking mouth designing. It analyzed the structure parameters of dust sucking mouth: vent face area S, its length L, width B, shrinking angleα, tilting angleβ, and pointed out their influence on the sucking efficiency. S is related to air flow speed in the vent tube under a certain flux and this speed decides the ability of dust sucking mouth to send the particles to the collecting box. L is associated with the single working width. The single working width increases with the increase of L. But too long L will decrease the side sucking ability. B is related to the flux of the side entrance and whether there is enough time for the particle's pick-up. The increase of shrink angle will decrease the equity of air speed distribution in dust sucking mouth, increase pressure loss and generally it must be less than 150°.A smaller titling angleβwill reduce the degree of difficulty in taking away the particles by air flow. Then it designed innovative structure of dust sucking mouth and it built the parameterized solid model and all parameters of this model are adjustable, which shortens the designing period. It simulated the flow field distribution by CFD which verifying the rationality of the design. In order to test the sucking mouth, it also designed the experiment equipment and manufactured it. This experiment equipment applied frequency conversion to change the fan speed continuously. The experiments on the experiment equipment indicated the designed dust sucking mouth had met the designing index. Lots of experiment on the spot verified that this design of the sucking mouth was successful in sucking kinds of dust particles and meeting the practical needs.