Development of an Algorithm for the accelerated Simulation of Roll Forming Processes

连续成形工艺设计的解析算法通常假定是平稳的。这一点对于辊压成型来说尤其如此。在工艺设计过程中，仍未考虑安装区域(即型材到轧制机架的入口处或出口处)的影响。相比之下，基于有限元方法的模拟为这些区域提供了准确的结果。到目前为止，它们的主要缺点是无法利用源于平稳性的进程中的相似性。因此，根据型材设计的不同，辊弯成形过程模拟的计算时间从几天到几周不等。该项目的方法是，一旦计算出的工艺状态变量变得稳定，就将它们外推到下一个成形步骤。通过使用简单的轮廓作为测试用例，该项目的头两年用于确定确定平稳性的合适标准，并识别对工件位置区域的范围和特征有影响的参数。这些结果导致了一种自动化算法的开发，该算法以一种方式增强了有限元模拟，使计算时间减少了大约1/4。50%。相应的结果与常规有限元模拟的结果相当，并得到了实验的验证。该项目的第三年旨在将所开发的算法应用于更复杂的型材。由德国型材制造商制造的实际型材作为测试案例，用于评估新方法在工业应用中的通用性和实用性。

Analytical algorithms for the design of continuous forming processes usually assume stationarity. This is especially true for roll forming. The impact of instationary regions (i.e. at the entrance or exit of profiles to the rolling stand) remains unconsidered during process design. In contrast, simulations based on the finite element method provide accurate results for these regions. Up to now, their main disadvantage is a disability to exploit similarities within the process originating from stationarity. Hence, computation time for the simulation of roll forming processes ranges depending on the profile design from several days to several weeks.The approach of this project is to extrapolate the calculated state variables of a process to the next forming step as soon as they become stationary. In doing so, stationary periods of the process with no significant changes of state variables can be skipped and thus the simulation is accelerated.Using simple profiles as test cases the first two years of the project served to determine suitable criteria for the determination of stationarity and to identify parameters with influence on the extend and characteristics of instationary regions of the workpiece. These results led to the development of an automated algorithm, which enhances the FE-simulation in a way that computation time was reduced by approx. 50%. The corresponding results were comparable to those of regular FE-simulations and validated by experiments.The third year of the project aims for an application of the developed algorithm to more complex profiles. An actual profile manufactured by a German profile manufacturer serves as a test case for an evaluation of the generalizability and practical usability of the new method for industrial application.