Discrete Element Simulation And Experimental Study Of Continuous Compound Mixer Stirring Process

In-situ thermal regeneration is a fast,economically and environmental friendly asphalt pavement maintenance process that can be used to repair the surface layer of damaged asphalt pavement,which has received wide attention in the road maintenance industry.As a key part of in-situ thermal regeneration technology for asphalt pavement,in-situ remixer can help solve the problem of serious accumulation of old asphalt mixture.However,there is a lack of research on the special equipment for continuous mixing of asphalt mixes.In this thesis,the structure and mixing performance of continuous remixers will be researched in depth according to their working conditions and asphalt mix material characteristics.Firstly,according to the overall design requirements of the continuous mixer,analyze the mixing process of the continuous mixer,the mixing mechanism of asphalt mixture and the factors affecting the mixing uniformity,and calculate the radius,length,mixing blade installation angle and installation inclination of the continuous mixer.At the same time,calculate the mixing power of the mixing blade arrangement and the driving system of the continuous mixer.Secondly,using 3D modeling software to draw and assemble the overall structure of the continuous mixer,and simulating different mixing speed,blade installation angle,installation inclination and filling rate based on EDEM discrete element method,and did three-factor four-level orthogonal experiments based on mixing speed,blade installation angle and installation inclination of the continuous mixer under the condition of certain feeding rate to analyze their primary and secondary effects.Finally,the experimental data of mixing uniformity,material capacity,drive system pressure and rotational speed are measured for the continuous remixer test equipment.The results show that the mixing blade speed of the continuous remixer is the main influencing factor of mixing uniformity,followed by the blade mounting angle and mounting inclination angle,and in order to improve the mixing quality,the suitable mixing speed should be selected as a priority.The accuracy of the simulation method and data is verified by measuring the data of the continuous mixer such as capacity,mixing time,mixing uniformity,motor inlet and return pressure.