Fused deposition molding process is a complex physical process. When the melt ejected from the nozzle falls onto the panel or the material of front layer which had been solidified, a chain of corresponding physical changes took place. The distance between the nozzle and the workpiece is very short, and the cooling speed of the ABS melt is very fast in the air. It is difficult to explore the changes of the sample through experiments. That expansion or contraction of the ABS melt in the air is directly to affect the measurement of shrinkage of the melt. At the same time, the temperature when the ABS melt falls on the panel, the temperature of printing also is directly affects to the temperature field of the workpiece. In order to obtain more accurate parameters of the FDM process and print more qualified products. It is necessary to establish the corresponding mathematical and physical model for the melt flow around the nozzle. The proposed method applies the principle of calculating fluid mechanics to make flow analysis and thermal analysis, which is based on Fluent. The simulation results can provide a reference for the optimization of process parameters.%熔融沉积成型过程是一个复杂的物理过程.从喷口挤出的熔体落到制作面板或前一层已固化的材料上的这段过程中,发生了很多相应的物理变化.但是因为喷头与工件之间的空间距离很短,ABS熔体在空气中的冷却速度非常快,通过实验来探究其变化较为困难.而ABS熔体在空气中可能发生的膨胀或者收缩问题,直接影响着熔体收缩率的测量.同时ABS熔体落到制作面板上的温度(打印温度)也直接影响了工件的温度场.为得到更精确的FDM工艺参数,打印出更合格的产品,有必要对喷口附近的熔体流动建立相应的数学模型和物理模型.并基于计算流体力学原理,应用FLUENT对其进行流动分析和热分析.模拟结果可为工艺参数的优化提供一定的参考.
展开▼
