Study On Spoiler Cavitation Addition Device Of Foam Dust Suppression

Mine dust is one of the most important occupational hazards and natural disasters in mine production.Foam has the advantages of good wettability,large coverage area and low water consumption.In recent years,although good results have been achieved in some mine dust reduction practices.However,due to the complexity of mine production conditions,foam dust reduction technology has been greatly restricted in the field of popularization and application.Especially for the blowing agent addition,the traditional Venturi cavitation addition device has large pressure loss,poor cavitation performance under low pressure conditions,and excessive cavitation under high pressure conditions,which causes severe cavitation damage to the device itself.In order to solve the above problems,this paper adopts a comprehensive research method combining theoretical analysis,numerical simulation,experimental verification and field application,and puts forward the research of the problem of spoiler cavitation addition device.The main results and conclusions obtained are as follows:A spoiler cavitation addition device is designed.By embedding the turbulent fluid at the inlet of the throat of the traditional Venturi cavitation addition device,and setting the pipette at the tail of the turbulent fluid.The fusion of the vortex cavitation mechanism in the turbulent wake and the shear boundary cavitation mechanism of the jet boundary layer is achieved,forcing the cavitation cloud in the device to appear only in the local range of the turbulent tail.This design idea not only enhances the cavitation performance and liquid absorption stability of the device under low pressure,but also eliminates the cavitation cloud in the boundary layer of the inlet of the diffusion tube,reduces the scope of cavitation damage,and improves the new addition device.Critical pressure ratio and on-site adaptability.Based on ANSYS Fluent,the optimization of the structural parameters of the new addition device was realized.Using the control variable method idea,through the establishment of numerical calculation models of different structural parameters for simulation analysis,under the existing conditions,the optimal structural design parameters of the new addition device are: the area ratio of the disturbance fluid to the nozzle outlet area is 0.04,the area ratio of the throat pipe is 1.0,The length of the throat is 10 mm.A shaped body with low shape resistance and good cavitation performance was selected as the turbulent fluid that actively induces cavitation.Finally,the critical pressure ratio of the new addition device was increased to 0.72.Compared with the traditional Venturi type addition device,in the cavitation state,the cavitation erosion range of the new addition device is smaller,and the energy loss due to cavitation is smaller.The experiment verified the correctness of the structural parameter design of the new spoiler addition device and the reliability of the field application.When the addition ratio is controlled at 0.5%,the critical pressure ratio of the new addition device is higher than 0.67.Finally,the new addition device was integrated with the foam dust suppression system.Through field experiments under different mine environmental conditions,it was verified that after the new addition device was applied to the foam dust reduction system,the stability of the foam jet was stronger and the dust reduction rate of respiratory dust Up to 85%,realizing effective control of dust pollution on site.Especially in the work place where the water pressure is lower than 300 kPa,in the case where the traditional device loses stability,the new addition device still has good cavitation performance and stability,indicating that the new addition device has a wider range of application.The present dissertation has 64 Figures,22 tables and 77 references.