Numerical Simulation Study Of Rubber Damage Mechanism In Abrasive Water Jet Recycling Waste Tyre

For both environmental and economic reasons,there is broad interest in recycling end-of-life tires.Water jet can be a successful technology for this to be achieved owing to its flexibility,selectivity and performance.The use of water jet to recycle used tyres can effectively avoid the pollution problems of traditional recycling methods and the coking of the rubber powder during the mechanical grinding process,which is a good complement to the traditional method of recycling waste tyres.Due to the strong destructive power of the abrasive water jet,it is more energy efficient than pure water jet,however,if the jetting parameters are not selected properly it can cause damage to the wire layer in the tire,both affecting the recovery quality and wasting energy,so it is necessary to study the mechanism of abrasive water jet recycling of used tire and the effect of jet parameters on the erosion effect.(1)In this paper,a detailed derivation of the strain energy function expressed as strain invariant and a numerical algorithm for calculating the stress increment from the integral point strain increment are obtained.Concerning the applicability of constitutive models in finite element software materials library,the VUMAT material subroutine is used for the secondary development of the finite element software,and the hyperelastic constitutive model that considers failure is embedded in the main program.(2)The finite element model of abrasive particle erosion rubber was established after reasonable simplification of the process in view of the complexity of abrasive water jet impact crushing rubber.The process of continuous stripping of rubber materials under abrasive particle erosion is simulated using the finite element method and the VUMAT subprogram mesh delete function.The results show that the equivalent strain is highest at the impact interface,meshes are removed after reaching the set point,and decays rapidly away from the impact interface.The destructive effect of stress waves is negligible.(3)The stress-strain distribution of the rubber target plate and the stress-wave reflection process during the erosion process were obtained,and the influence of jet pressure,jet angle,abrasive particle size and abrasive particle number on the erosion volume was analyzed.The results show that particle kinetic energy is the key factor affecting the erosion volume,the jet pressure,abrasive particle size,the number of abrasive particles is proportional to the erosion volume;there is an optimal incidence angle of 85°;the erosion effect of abrasive particles with particle size less than 125?m is negligible.The results of this paper help to understand the crushing mechanism of rubber under the impact of abrasive particles,and provide theoretical support and technical guidance for the efficient recovery of used tyre from abrasive water jet and the determination of optimal jet parameters.