Design Of Hydrostatic Bearing With Trapezoidal Oil Chamber And Research On The Temperature Field Based On FLUENT

Hydrostatic bearings have characteristics of low friction,large bearing capacity,high stability and reliability,good shock-absorbing performance,and high precision of rotation.These advantages have attracted widespread attentions,and hydrostatic bearings are widely used in precision processing machinery and high-speed,high-precision equipment.The oil film temperature rise is mainly due to the mutual shear action of the lubricating oil caused by the rotation of the main shaft,thereby generating a large amount of heat.Oil film temperature rise will not only directly reduce the viscosity of the hydraulic oil,affect the oil film bearing capacity,but also cause serious thermal deformation of the parts,resulting in contact between the shaft and the bearing,thus affecting the normal operation of the bearing,and even caus-ing an accident.Therefore,solving the problem of temperature rise is crucial to ensure the performance of hydrostatic bearings and prolong the service life of the bearings.Many scholars have also been committed to studying the problem of reducing the temperature rise of the oil film.In view of this,this paper takes the hydrostatic bearing as the research object,aiming at its common oil film temperature rise problem,a new trapezoidal oil cavity bearing is designed,and then the new structure and the original structure are analyzed and compared by numerical simulation method,it is proved that the trapezoidal oil chamber bearing has a significant effect of reducing the temperature rise of the oil film.Then the other properties of trapezoidal oil cavity bearing were analyzed.The main research content of this paper is as follows:Chapter One: Summarizes the research background and significance of hydrostatic bearings,introduces several typical structures,and analyzes the research status of hydrostatic bearings at home and abroad.Chapter Two: The working principle of hydrostatic bearing is expatiated in detail.The bearing capacity and temperature rising characteristics of the hydrostatic bearing oil film are analyzed.The temperature rise equation of the oil film under working condition is deduced.Then,an overview of computational fluid dynamics is presented.Established the control equation and put forward basic assumptions,which provide a theoretical basis and conditions for subsequent solutions.Chapter Three:Given the structural dimensions of the hydrostatic bearing fluid model,a three-dimensional model of the rectangular oil bearing bearing fluid modeland trapezoidal oil cavity bearing fluid was established using Pro/E software.Then using ICEM software made a structured meshing of the fluid model.Prepared for the subsequent introduction of FLUENT solver calculations.Chapter Four:FLUENT software was used to solve the temperature field distribution of the oil film at the spindle rotation speed of 2000 rpm in two fluid models of rectangular and trapezoidal oil cavities.The temperature distributions on the two oil films were analyzed and summarized,and compared the differences between the two oil film temperature fields.The oil temperature field simulations were performed successively for the two models at the other three rotational speeds(1000rpm,1500 rpm,and 2500rpm),and the average temperature of the two model oil films at four rotational speeds was analyzed.Finally some important laws and conclusions were obtained.Chapter Five:The temperature field of trapezoidal oil chamber bearing model oil film under different film thicknesses was simulated,and it was proved that the oil film temperature rise gradually decreased with the increase of oil film thickness.Then calculate the temperature field of trapezoidal oil chamber bearing oil film when the spindle rotates in the reverse direction.The results show that the trapezoidal oil chamber hydrostatic bearing can only reduce the temperature rise of the oil film when it is working in the forward rotation direction,and the temperature rise of the oil film in reverse rotation is higher than the temperature rise of the oil film in the rectangular oil bearing.Finally,the relationship between oil supply pressure and trapezoidal oil film temperature rise was simulated and analyzed.