CAE Of Extruding For Polymer Wider Waterproof Sheets

It is urgent for the engineering, such as building, water conservancy, tunneling, and the subterranean waterproof, to use the waterproof materials with lager width and high quality. It was tried to make the extrusion die for the wider waterproof materials by magnifying the one for the narrow products in proportion to its size and failed at the end. The thesis majors in finding the way of designing a extrusion die for the wider waterproof sheet, on the basis of analyzing the distribution of fluid field in the flow channel of the die, and the influence of the geometry, the pressure in the die and the power-law factor of the materials on the uniformity of the field distribution. Such main points as the way of simulating the three-dimensional fluid field by the ANSYS software, a visual expression of the fluid distribution in the flow channel, the important results for the optimization and the improvement for the design of the extrusion die were given in the article.All of the studies on the fluid flied were based on the three-dimensional models of the flow channel made by the ANSYS software. The documents searched indicated that the research on the subject was made on the assumption that the flow was two or one dimension erenow. The simulation results of the cylinder-block model were given in the article, consistent with that of Middlemen's. It was shown that the block part could improve the uniformity of the flow distribution. The analysis of the flow field of some materials with different power-law factor in the die designed by Mckelvey was close to that of Mckelvey's. It was shown that the flow distribution was uniform in the die that can producesheets with 1200mm in width. During the analysis the flow channel was divided into several parts to get the details about the fluid flow in each area. A conclusion was drawn after analyzing the influence of the die pressure on the flow distribution, that the higher pressure is good for the output and bad for the uniformity of the distribution. Simulation of the die applying the cylindrical main runner showed the fact that when the cylinder replaced the cone the change of uniformity was trivial. The uniformity of the non-block flow channel was so poor that the block in the proper position of the die channel was necessary. The project of the die for the wider sheet was put forth, and the analysis of the fluid flow in the die was shown. As far as the practicability of the die for the thickness, the height of the block would be adjusted when extruding the sheets with different thickness.