Automated simulation-driven analysis of lightweight design strategies for the efficient design of film extrusion dies – optimisation of both die mass and flow path length and reduction of thermal setup time

对轻量化设计策略进行自动仿真驱动分析，以实现薄膜挤出模具的高效设计 – 优化模具质量和流路长度并减少热设置时间

• 批准号: 518072893
• 负责人: Professor Dr.-Ing. Christian Hopmann
• 金额: --
• 依托单位: Institut für Kunststoffverarbeitung (IKV) in Industrie und Handwerk an der RWTH Aachen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/518072893?language=en
• 关键词: Automated; simulation; driven; analysis; lightweight

Extrusion dies are used to continuously form complex products such as a co-extruded film spanning several meters in width. The combination of high pressures due to high viscosity, multiplicity of flow channels in a co-extrusion die and the large product width means that high mechanical loads act on the extrusion tools. To ensure that the individual die plates remain sealed against each other despite these loads, the die plates are sized conservatively, i.e. sized to be very voluminous and thus very rigid. In turn, the large volume or the resulting large masses leads to difficulties in handling, long flow paths and long thermal setup times. Thermal setup times occur when waiting for the die to heat up or cool down when changing to a new product. It is - as of today - not known to what extent a deviation from the conservative sizing for extrusion dies of different types and dimensions is a) possible and b) beneficial. The research project applied for therefore creates essential basic knowledge. It does that by investigating different lightweight design strategies using simulation. In the research project applied for, different simulation-driven lightweight design strategies are therefore investigated. The aim is to find out - depending on the size and type of extrusion die - which lightweight design strategies lead to lower masses, reduced flow paths and shorter heating times. In order to achieve this goal, however, a simulation environment must first be created that can accurately capture the interactions that occur between strongly geometry-dependent flow in the flow channel and flow-dependent deflection of the die plates. In addition, this simulation environment must allow the geometry of the tool plates to be automatically adjusted. Both challenges can be met by using the immersed-boundary-surface method, which has hardly been established in plastics processing so far. First, this method will be validated by means of a comparison with conventional calculation methods and laboratory tests with a particularly flexible tool made from PMMA. Afterwards, the following lightweight design strategies are applied automatically: substitution of steel by aluminium, stiffening by curvature, highly precise mechanical design, ribbing as well as topology optimization. Two fundamentally different designs of extrusion dies and seven different die sizes between 300 and 5000 mm in outlet width are investigated. The simulated improvements regarding tool mass, flow path length and heating time are analyzed in detail and compared to industrial dies. With this data, a majority of the extrusion dies can be evaluated with regard to the potentials of lightweight design for the first time. Two optimized dies are manufactured and examined in extrusion tests, so that - in addition to the calculation method - the optimization method can be validated.

挤压模具用于连续形成复杂的产物，例如跨越宽度几米的共同攻击膜。高压的组合由于高粘度，同时排列模具中的多样性流通量和较大的产品宽度意味着高机械载荷作用于挤出工具。为了确保单个模具板仍然彼此密封，尽管有这些负载，但模具板的尺寸是保守的，即尺寸非常大，因此非常刚性。反过来，大容量或所产生的大质量会导致处理困难，长流路和较长的热设置时间。当更换新产品时，等待死亡加热或冷却时会发生热设置时间。到目前为止，它尚不清楚与保守大小的偏离程度在多大程度上偏离了不同类型和维度的挤压死亡，a）可能是可能的，b）有益。因此，研究项目适用于创建基本知识。它通过使用仿真来研究不同的轻质设计策略来做到这一点。因此，在应用的研究项目中，研究了不同的模拟驱动的轻型设计策略。目的是根据挤压模具的大小和类型来找出，而轻量级设计策略会导致质量降低，流动路径减少和较短的加热时间。但是，为了实现这一目标，必须首先创建一个模拟环境，该环境可以准确捕获流道中强烈的几何相关流与模具板的流依赖性偏转之间发生的相互作用。此外，此模拟环境必须允许自动调整工具板的几何形状。可以使用沉浸式界面方法来应对这两种挑战，到目前为止，在塑料处理中几乎没有建立这种挑战。首先，将通过与常规计算方法和实验室测试与PMMA制成的特别灵活的工具进行比较来验证该方法。之后，自动采用以下轻质设计策略：用铝替换钢，通过曲率，高度精确的机械设计，肋骨以及拓扑优化的僵硬。研究了两种根本不同的挤压模具设计和七个不同的模具尺寸在300至5000 mm之间。对工具质量，流路长度和加热时间的模拟改进进行了详细分析，并与工业模具进行了比较。有了这些数据，大多数挤压模具可以首次就轻量设计的潜力进行评估。在挤出测试中制造和检查了两个优化的模具，因此 - 除了计算方法外，还可以验证优化方法。