Taking vibration converter of intelligent damper for drill strings as the study object,this paper analyzes the influential factors of motion state of the ball and conducts an explicit dynamics simulation by establishi...Taking vibration converter of intelligent damper for drill strings as the study object,this paper analyzes the influential factors of motion state of the ball and conducts an explicit dynamics simulation by establishing a mechanics model of vibration converter.The study basis is Newton’s laws of motion,d’alembert’s principle and hertz contact theory.And we use world coordinate system,rotating coordinate system and Frenet coordinate system to deduce kinematics equations of vibration converter.The ultimate result demonstrates that the axial velocity and maximum contact stress change with the increment of ball diameter and helix angle.It also proves the validity of our derived kinematics and mechanical models and provides a good consultant value for the design and theoretical arithmetic of vibration converter for intelligent damper of drill strings.展开更多
基金This work was supported by National Natural Science Fund of China(51222406,51004082)New Century Excellent Talents in University of China(NCET-12-1061)+1 种基金Scientific Research Innovation Team Project of Sichuan Colleges and Universities(12TD007),Sichuan Youth Sci-tech Fund(2011JQ0020)the 7th graduate innovation funds of Southwest Petroleum University(GIFSS0720),and Special thanks to PhD C.S.Shi.
文摘Taking vibration converter of intelligent damper for drill strings as the study object,this paper analyzes the influential factors of motion state of the ball and conducts an explicit dynamics simulation by establishing a mechanics model of vibration converter.The study basis is Newton’s laws of motion,d’alembert’s principle and hertz contact theory.And we use world coordinate system,rotating coordinate system and Frenet coordinate system to deduce kinematics equations of vibration converter.The ultimate result demonstrates that the axial velocity and maximum contact stress change with the increment of ball diameter and helix angle.It also proves the validity of our derived kinematics and mechanical models and provides a good consultant value for the design and theoretical arithmetic of vibration converter for intelligent damper of drill strings.