Heat transfer simulations of the fused filament fabrication process are an important tool to predict bonding, residual stresses and strength of 3D printed parts. But in order to capture the significant thermal gradients that occur in the FFF printing process, a fine mesh discretization and short time steps are required, leading to extensive computational efforts. In this work a simulation framework is presented which combines several efficiency measures with the objective of reducing the computational efforts required in simulating the FFF printing process without simplifying the deposition physics or reducing the overall accuracy. Thus, the material deposition has been modeled with a hybrid element activation approach and elements are adaptively coarsened through an error-based coarsening condition. Additionally, an appropriate coarsening technique is presented for geometries with air-filled infill patterns. The accuracy of the numerical framework is experimentally validated and the efficiency of the framework is validated numerically by comparing the performance of models with and without any efficiency measures. Finally, its effectiveness is shown by simulating the printing process of a larger geometry.

翻译：熔融沉积成型过程的热传导模拟是预测3D打印部件粘结、残余应力和强度的重要工具。然而，为捕捉FFF打印过程中出现的显著热梯度，需要采用精细网格离散化和短时间步长，这导致计算工作量巨大。本研究提出了一种模拟框架，该框架结合了多种效率优化措施，旨在无需简化沉积物理过程或降低整体精度的前提下，减少模拟FFF打印过程所需的计算量。具体而言，材料沉积采用混合单元激活方法建模，并根据基于误差的粗化条件对单元进行自适应粗化。此外，针对具有空气填充填充图案的几何体，提出了一种合适的粗化技术。该数值框架的准确性通过实验验证，其效率则通过比较有无效率优化措施的模型性能进行数值验证。最后，通过模拟较大几何体的打印过程，展示了该框架的有效性。