Accelerating EDEM simulations with Recorded Factories
Optimizing the equipment and systems in manufacturing processes across all industries is crucial to reducing costs and ensuring the quality of the output products. While physical testing is time consuming and costly, it is possible to conduct the optimization through accurate simulation software such as Altair® EDEM™, which relies on the Discrete Element Method (DEM), to carry out the necessary simulations to fine-tune the equipment.
However, DEM models can be highly computationally expensive, this connected to the requirement to run multiple simulations to find the optimal design or process parameters can result in running many demanding and lengthy simulations until the final solution is reached.
The new Recorded Factory feature showcased in the video below, allows the users to record the material flow of a simulation once, and then use it as an input in subsequent simulations. This allows the user to run multiple virtual tests much faster. The video below of a continuous mixer, shows the benefits of using recorded factories compared to traditional iteration methods using EDEM, with recorded factories being 3.2 times faster compared to volume packing.
The model at hand, the continuous mixer, will keep mixing material for as long as it is operating, while new material is being added into the hoppers to keep the process going at regular intervals. The mass flow rate in the hopper outlet gradually decreases due to the reduction in pressure from upper material layers. Thus, when fresh material is introduced to the hoppers, the mass flow rate registers a spike, caused by the sudden addition of new material to the mass remaining in the hoppers. This spike has been captured using both methods, volume packing and recorded factories. The mixer has been optimized to maximize its mixing efficiency, which occurs on the last 1/3rd of the drum. As shown in the concentration graph below, the two materials are mixed to an exceptional degree.
Figure 1. Concentration graph of smallest particles
In previous versions of EDEM, the refilling of the hoppers would only be achieved using factories such as volume packing or static factories. The factories are geometries which are filled with material in the simulation and then allowed to flow under gravity. The material generation process through traditional EDEM factories adds to the simulation computational expense and requires fine tuning to ensure that the desired material flow rate is obtained with the minimal computational expense possible. This procedure takes additional engineering time to set up and the resulting simulation requires significant disk space.
Figure 2. Recorded factory simplification diagram.
What’s New in EDEM 2022.3 – EDEM Release Highlights
What’s New in EDEM 2023.1 – EDEM Release Highlights
The simulations are very closely matched, with minor discrepancies that arise from inconsistencies in the volume packing method. The recorded factory not only offers a high degree of similarity, but it is additionally repeatable with practically zero discrepancies between subsequent loops, allowing the user to iterate the simulation to perfect the design.
Figure 3. Continuous mixer render. Rendered in Inspire Studio
To provide an example, Altair® HyperStudy® can be used to carry out topology optimization on the parts of the equipment geometries and recorded factories can help speed up the process.
It is important to note that there are details the user must pay close attention to use recorded factories correctly. Firstly, the recorder and the factory geometry must be identical and shaped to encompass all the material flow. Secondly, the thickness of the geometry is critical to the performance of the recorded factory and must be setup to be approximate to the diameter of largest expected particle in the simulation. Small thickness will result in a stuttering flow and too large thickness will have additional computational expense. Additionally the simulation using the recorded factory must be run at the same time-step as the original case.
For additional information on how to use EDEM use the following links: