In this blog, we’ll take a look at an air spring (Figure 1). This device is used for vibration isolation as well as suspension, for example in heavy weight vehicle applications.

Figure 1: Example of an air spring.

The example shown here consists of a convoluted bellows (two convolutions), with steel plates on each end. In practice, one to three convolutions are used. The bellows is made of rubber that is reinforced with fibres. A steel girdle hoop helps to keep it in shape when it is filled with compressed air.

Sometimes the results I get from Abaqus are not what I expect. Perhaps the analysis does not complete while I didn't think it would be very troublesome, or I do get results, but they don't make sense to me. Though this can be very frustrating, it can also be seen as an interesting puzzle (especially if it is somebody else's problem ;) ). For that reason, I'd like to share some results with you that did not make sense to me. Let's see whether you can figure out what went wrong!

As a consultancy company, we regularly receive geometry files from external parties. Typically this geometry isn’t ideal for simulation purposes: it includes details that are not of importance for the analysis, while they will negatively impact meshing and simulation time. Therefore, it is beneficial to remove some of the features from the geometry (defeature it) for simulation purposes.

As you may have noticed, we're working on kind of a series of blogs on the simulation of different production techniques. This time, we will look at roll forming.

Roll forming

During the roll forming process, a long strip of sheet metal is continuously bent into the desired cross-section. The strip passes through a number of sets of rollers, where each set performs a part of the total desired bend, until the final profile is obtained.

In this blog we will discuss the process to determine movement of bodies due to a fluid flow, performed with XFlow CFD. As an example we have taken a historic measurement device called a "Wildse Vaan".

In this blog post, we will be discussing about metal tube hydroforming with Abaqus. We will be using forming limit diagrams to create the material's strain envelope, for avoiding necking (rupture), a possible failure mode, in this type of metal forming process. This will be demonstrated in a hydroforming process simulation of a metal bellows joint.

Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mould, and trimmed to create a usable product (https://en.wikipedia.org/wiki/Thermoforming). Often a vacuum and maybe even a plug is used to help the sheet take the shape of the mould.

When producing a part, you want it to match the design, the geometry. How to achieve this is not always evident.

For example, when the part is created from sheet metal by pressing it between an upper and lower die, the final part may not fully match the space in between the dies due to the spring back effect. If the deformation would be fully plastic, then the deformed shape will not change during unloading. If it is partially elastic, then the elastic deformation is recovered upon unloading and hence the final shape differs from the shape between the dies. In this blog I’ll give an example of this effect, showing that we can model it with Abaqus.

Sometimes you may wish to simulate a process where various parts interact with one another. In such cases it is often impossible to rely on predefined loads and boundary conditions, since the exact points of contact are dependent on the solution. Including contact in your simulation can be a more realistic way to represent loadings.

Abaqus provides a wide range of mechanical models and numerical methods for contact. We will begin this month’s webinar with an overview of these capabilities, considering how to select the best options for a given problem. We will then move on to some challenging example problems and investigate how advanced features of Abaqus contact can help convergence and ensure you obtain realistic solutions.

In this blog post, we will be showcasing a fully coupled fluid structure interaction (FSI) analysis, of a peristaltic roller pump. This study will focus on assessing the performance of a peristaltic pump, under operation. This co-simulation analysis, will solve for both the structural and fluid domains' unknown quantities, during 1 revolution of the rotating mechanism of the pump.

This is an example of a challenging application, in which numerical modelling and computer simulations can provide a lot of insight and value.

The aspects we want to evaluate in this digital model are; determining the volume flow-rate for a given rotation speed, assessing contact stress areas on the tube, and determining the torque output for the given rpm.