混凝土搅拌车搅拌筒磨损数值分析

混凝土运输过程中搅拌筒的磨损一直是一种常见潜在危害,磨损严重时会导致叶片失效,对搅拌的质量和出料匀质性产生影响。通过实验获取搅拌筒内部的磨损费时费力,因此有必要采取一种数值分析方法对搅拌筒的磨损进行预测并提出改进。本文采用摩擦磨损实验的方法来标定颗粒与搅拌筒之间的Archard磨损常数,采用JKR接触模型表征混凝土的流动性能,采用离散元方法(DEM)对搅拌筒筒体及叶片磨损进行预测分析。通过法向接触能量与切向接触能量的对比,证明搅拌筒中的磨损主要为伴有冲击作用的磨粒磨损,搅拌车搅拌筒中搅拌叶片顶部的磨损较为严重。针对磨损比较严重的叶片顶部进行改进,采用T型耐磨结构等改进叶片结构,叶片顶部结构改进后搅拌筒使用寿命能得到明显提升。

Numerical analysis of abrasion of concrete mixer drum

Wear of the mixing drum during concrete transportation has been a common potential hazard,which can lead to blade failure when the wear becomes severe,affecting the quality of the mix and the homogeneity of the discharge.It is necessary to adopt a numerical analysis method to predict and propose improvements to the wear of the mixing drum since it is time consuming and laborious to measure the wear inside the barrel experimentally.In this paper,a frictional wear experiment is used to calibrate the Archard wear constants between the particles and the drum,a JKR contact model is used to characterize the flow properties of concrete,and a DEM is used to predict the drum and blade wear.The comparison of normal contact energy and tangential contact energy shows that the wear in the mixing drum is mainly abrasive wear with impact,and the wear on the top of the mixing blade in the mixing drum of the mixer truck is more serious.For the more serious wear blade top.T-type wear-resistant structure is used to improve the blade structure.After improving the blade top structure,the service life of the mixing drum can be significantly improved.