摘要
采用摩擦学性能测试与EDEM仿真模拟相结合的方法,研究了跨黏度纤维素在不同转速和不同载荷下的摩擦学行为,以及在摩擦过程中对螺杆表面的磨损机制.跨黏度纤维素的摩擦学性能测试采用"球-盘"式摩擦磨损试验机,而对螺杆的磨损机制采用Archard Wear磨粒磨损计算公式及离散元方法构建纤维素及螺杆磨损机制模型.研究结果表明,在高转速60 r/min条件下,跨黏度纤维素的磨损规律受施加载荷大小的影响较大,15 mPa·s的摩擦系数在0.19 至0.44 之间,100000 mPa·s的摩擦系数在0.25 至0.52 之间;在低转速10 r/min条件下,摩擦系数受法向载荷影响波动较大,15 mPa·s的摩擦系数在0.25 至0.44 之间,100 000 mPa·s的摩擦系数在0.24 至0.58 之间.通过EDEM仿真模拟发现,随着纤维素黏度增大,纤维素与螺杆表面的接触面积随之减少,螺棱在对纤维素推动的过程中,不易造成纤维素在螺槽中的相对滑动,进而减少螺槽部位的磨损.纤维素的黏度大小对润滑效果有一定影响,但并不是决定性因素;影响纤维素的润滑效果和磨损机理的主要是加载载荷,其中磨损程度随着载荷变大而加深,而磨损机理以磨粒磨损为主.同时,纤维素黏度会对螺杆的磨损位置和磨损程度产生影响.
Abstract
A combination of tribological performance tests and EDEM simulation has been used to study the tribo-logical behavior of cross-viscosity cellulose at different speeds and loads,as well as the wear mechanism of a screw surface during friction.The tribological properties of cross-viscosity cellulose were tested using a"ball-disk"fric-tion and wear testing machine.The wear mechanism of the screw was postulated using the Archard Wear model and finite element methods.The results show that the applied load significantly affects the wear law of cross-viscosity cellulose for a high rotation speed of 60 r/min,the friction coefficient for 15 mPa·s is between 0.19 and 0.44,and the friction coefficient for 100000 mPa·s is between 0.25 and 0.52.For a low speed of 10 r/min,the friction coef-ficient fluctuates significantly under the influence of normal loads.The friction coefficient for 15 mPa·s is between 0.25 and 0.44,and the friction coefficient for 100 000 mPa·s is between 0.24 and 0.58.EDEM simulations showed that as the size of the cellulose increased,the contact area between the cellulose and the screw surface de-creased.In the process of pushing cellulose by the screw edge,it was less likely for the cellulose to slide relative to the screw groove,thus reducing the wear of the screw groove.Although the viscosity of the cellulose has some influ-ence on the lubrication effect,it is not the decisive factor.The primary influence on the lubrication effect and wear mechanism of the cellulose is the applied load;the wear degree increases with increasing load,and the wear mech-anism mainly involves abrasive wear.At the same time,the viscosity of the cellulose will affect the wear position and wear degree of the screw.
基金项目
国家自然科学基金(51905295)
辽宁省航发材料摩擦学重点实验室开放基金(LKLAMTF202304)
清华大学高端装备界面科学与技术全国重点实验室开放基金(SKLT-KF21B09)
维普
万方数据