The following is an excerpt.
How can we minimize the risk of electric vehicle batteries catching fire? How to design maximum safe vehicle security barriers? And how can we utilize 3D-printed components in protective structures? See the list of this years Master´s projects.
In all 20 MSc students have embarked on the final sprint to complete their diplomas in civil engineering at SFI CASA. The students will work on 13 different topics – as shown in the table below. The subjects revolve around the behaviour and modelling of materials, components and structures exposed to dynamic loads.
Methods and tools for the industry
Relevant materials are metals, polymers and glass, concrete, and composites. Also, this spring, there are 3 MSc-theses connected to wood, as in glulam and cross-laminated timber. Associate Professor Haris Stamatopoulos from the Department´s research group on wood-based materials and timber structures supervise the students with SIMLab´s Professor Arild Holm Clausen. Relevant materials are metals, polymers and glass, concrete, and composites. Also, this spring, there are 3 MSc-theses connected to wood, as in glulam and cross-laminated timber.
SIMLab works at the intersection of mechanics, design, dimensioning and material technology. The group develops models and methods that the industry can use in projects and product development. Applications are, for instance, protective structures, energy absorbers, junctions, and bridges.
The key to modelling the deformation and fracture correctly with the element method is to understand the mechanisms on a micro-scale. In addition, the group utilizes the laboratory actively to study the behaviour of materials and components.
Electric vehicle batteries
One MSc project is «Mechanical testing and numerical simulation of car batteries subjected to extreme loads and deformations». The project description states that there are undoubtedly benefits of electrifying our transport fleet – from reduced air pollution to enabling us to achieve the essential net-zero targets. Fundamentally, electric vehicles are extremely safe, but the main danger occurs if the battery cell walls of a lithium-ion battery are damaged. Collisions can easily trigger a hazardous EV fire. Such events can generate numerous organic chemicals, including toxic and potential, fatal gases. A complete mechanical characterization of the materials in the battery cells is key to designing safer and more efficient electric vehicles. This MSc project will run quasi-static and impact mechanical tests on commercial lithium-ion car batteries. The aim is to better understand their mechanical behaviour under extreme loads and deformations.
Fracture in steel pipes for CO2 transport
Another MSc topic is modelling running fracture in steel pipes for CO2 transport. The backdrop is CO2 capture and storage. The technology relies on a safe system to transport gas through pipelines. If subjected to accidental loads and owing to the internal pressure running fracture can occur in the pipes. Given the prevailing high pressure of liquid CO2, established standard calculation models for fracture in pipelines cannot be applied. Therefore, developing a numerical model for this specific application is necessary.
The main idea behind this project is to use the Gurson model to perform virtual testing. After that, the students should establish a simplified fracture model for large-scale simulations of running fracture in pipelines based on shell elements.
Artificial neural networks and additive manufacturing
One student will be working on «Modelling tensile ductility using artificial neural networks». Ductile fracture of metals occurs by nucleation, growth, and coalescence of voids on inclusions and second-phase particles during plastic deformation. The topic is part of a project aiming to investigate the use of Artificial Neural Networks to predict tensile ductility in 6000-series aluminium alloys. Virtual datasets created from micro-mechanically based finite element analyses with the Gurson model are used for training and validation. The validity of trained ANNs is assessed by comparison with existing experimental datasets.
3D-printed protective structures
Additive manufacturing is used to 3D-print various types of components with complex geometry. For example, one can now 3D-print larger panels and lattice structures in different polymers or metals. Such components are of great interest in physical safety where weight is essential, such as facades. So far, it has been challenging to obtain studies of 3D-printed parts used as energy absorbers in protective structures. The MSc project implies numerical simulations, 3D printing of components, material tests, and characterizations, e.g., computer tomography. Component tests in The SIMLab shock tube are part of the project.