The Flow Simulation And Optimization Design Of Extrusion System In 3D Printing Rock Material

With the development of 3D printing technology,it has greatly changed the traditional manufacturing methods.It is widely used in machinery manufacturing,aerospace and military equipment and other fields.The types of materials used for 3D printing are very rich.Both organic and inorganic materials can be used as 3D printing materials.In recent years,rock-like materials instead of the original rock specimens are more and more favored for experimental research.Rock materials of 3D printing are gypsum(calcium sulfate),cement,quartz sand,barite powder,and other materials.It has made some progress in the construction industry recently.The study of rock-like samples instead of core samples will inevitably provide more extensive means and basis for analyzing the physical and mechanical properties of the rock core.Combining the advantages of 3D printing technology,it is studied a new sample preparation method—3D printing rock materials in this paper.By studying the rheological properties of different water-cement ratio cement pastes,the rheology characteristic curve of 3D printing rock slurry was obtained,and a suitable range of cement ratio was found.Based on this,a kind of printing mechanical device was designed which can use rock-like material as printing material,then the flow field of screw section and nozzle part of the printing device was simulated.The jet characteristics of the nozzles with different structures and geometric parameters were simulated.The influence of various parameters on jet velocity of the nozzle was studied.The structure of printing device was optimized based on the numerical simulation results.The results of 3D printing rock material experiments showed that the feasibility of the design.