Applications

This example models a jet acting on a bearing. This jet creates a thin layer of air between the bearing and the support. The force acting on the bearing permits to compensate the gravity force.
The figure represents the jet with arrows indicating the direction of the flow. It can be seen that a vortex is created between the bearing and the support. Particles Tracking (coming from the jet) has been used to visualise this vortex.
This application has been solved with OOFELIE coupled with FINE™/Hexa.

This example models a 3D duct whose upper part has can oscillate. The fluid flow is supposed compressible. The Von Mises constraints are represented on the structure and the velocity field is plotted in the fluid domain.
This application has been solved with OOFELIE coupled with FINE™/Hexa.

This example illustrates a simulation of the opto-electro-thermo-mechanical actuation of a bi-layer micro-mirror. This mirror is composed of two layers made of materials with different thermal expansion coefficients. The extremity of an “arm” of the system is submitted to a given electric potential while the others have a null potential. Due to this difference of potential between the different extremities, a current appears through the system and causes heating by joule effect. Because the thermo-mechanical behavior of the two layers is different, a bending effect appears and it is possible to control the elevation of the device by modifying the applied voltage. The optical impact of mirror displacement is then obtained.

A support was generated around two mirrors that are defined in a ZEMAX provided design. The complete structure is cooled. The impact of the material used for the support of the two first mirrors (off-axis design) was analysed. In this particular case, a change from aluminium to titanium for the support reduces by a factor 4 the perturbation of the merit function value.

This example is a thermically-actuated micro-mirror. This mirror is made of 2 layers with different thermal expansion coefficient. The thermal actuation is often used in MEMS since the small dimension of the system induces fast response to thermal excitation.

The electrostatic effect is very important in MEMS since it is generally the most important force inside them. For example, the pull-in voltage detection is an important characteristic in MEMS simulation to prove the stability of a MEMS design.

This application illustrates the 2D transport of the temperature in a duct with a cylinder placed in its middle. The fluid flow has been computed at a first time. Then the transport of the temperature has been computed (a different value of the temperature has been imposed at the inlet and on the walls). The diffusion of the temperature in the cylinder has also been computed with equality of the values at the interfaces.

This example illustrates a simple incompressible inviscid flow around a car (fluid can go above and under the car), modelled with a simplified geometry. A mesh made of only tetrahedrons has been used. Streamlines of the flow are represented on the following figure.

This last application is the simulation of the electromagnetic actuation of a very small conductor pipe with ellipsoidal cross-section. This kind of actuation allows for example to control a fluid flow passing through the pipe by sequencing the different coils placed along the wall.

When a conductor is placed in a variable magnetic induction, eddy currents appear at its surface (and in a depth depending on the frequency of the excitation current, on the electric conductivity and on the magnetic permeability of the material). These currents cause power dissipation by joule effect and an increase in the conductor’s temperature. The aim of this example is to heat one tooth of a milling cutter for maintenance purposes. An inductor submitted to a sinusoidal electromotive source is placed close to the tooth we want to heat. It generates eddy currents in the milling cutter and consequently a local heating.

Model reduction techniques can be applied to many fields of activities.

This feature is intensively used in the microsystems (MEMS) component design procedure. Indeed, simulations at circuit level require accurate compact models of the MEMS components, also called behavioural models or reduced order models (ROM), to be generated from 3D expensive numerical model. These reduced models are written in HDL (Hardware Definition Language) and inserted, in a schematic form, is specific microelectronic simulators.

The coupled eigen modes of a water filled tank are extracted using OOFELIE::VibroAcoustics package. In this case, even if we are not interested in acoustic field inside the cavity, we have to take it into account since it has a strong impact on the behaviour of the global system. In this example, the mesh mapping algorithm was used since the acoustic and structural mesh are incompatible.

An example of acoustic radiation problem using the mesh mapping capability is showed here. We have the structural CAD model (simplified real model, for confidentiality reasons, presented on Figure « Engine CAD model ») and an acoustic CAD model.

Piezoelectric ultrasonic motors offer great advantages over conventional electromagnetic motors (such as torque to size and weight ratio, reduced noise, small and compact, etc.).

The linear engine is another type of piezoelectric engine. In this example, by applying an adequate harmonic voltage to the two piezoelectric stacks of the actuation system, we can obtain an elliptical movement of its upper face.

Combining the piezoelctric and vibroacoustics capabilities of Oofelie enables studying the behaviour of loudspeakers systems where the vibrating membrane is actuated using piezoelectric strips.