Design And Simulation Of Portable Geophysical Drilling Rig Based On The Principle Of Negative Pressure

At present,Luoyang shovel is the main domestic exploration method aimed at the geology of the loess plateau in the northwestern region,which cannot meet today's exploration needs.In order to improve the working conditions of geological exploration in the loess plateau area,this paper designs a portable geophysical drilling rig based on the principle of negative pressure.The drilling rig uses air to discharge soil,does not need to be suspended during the operation and does not rely on water sources,and is suitable for the geological conditions of the loess plateau area.The specific research content is as follows:(1)Refer to domestic and foreign literature,familiar with the development of domestic and foreign geophysical drilling rig and the characteristics of each type of geophysical drilling rig,summed up the advantages and disadvantages of the existing drilling rig.A new type of negative pressure geophysical drilling rig is put forward.(2)The design of the drilling machine uses negative pressure conveying,so the negative pressure conveying theory is summarized,the basic parameters of negative pressure conveying are determined,and the classification of pneumatic conveying and the flow pattern of vertical conveying are studied.Then the gas-solid two-phase flow theory is summarized to lay a theoretical foundation for the simulation.(3)The overall structure of the designed negative pressure geophysical drilling rig is determined to be gasoline generator + negative pressure pump + conveying hose + electric motor + scraper bit.The generator,negative pressure pump,conveying hose and scraper bit are directly selected,and the design and selection of the electric motor are carried out(4)Fluent software was used to simulate the flow field distribution of the drilling inlet holes,and three inlet holes were determined as the design scheme;At the same time,the DPM model in Fluent is used to simulate and analyze the soil carrying capacity of the negative pressure drilling machine under different intake speeds of the three holes,and the working capacity of the drilling machine is confirmed to meet the requirements.(5)For drilling RIGS that may occur in the process of bending,by using the Fluent software of multiphase flow model and turbulent model,respectively for different bending Angle of bent tube of gas-solid two-phase flow are analyzed in numerical simulation,and to determine the pressure drop under different bending Angle of bent tube,the optimal bending Angle is determined.