Themes for Bachelor and Master

Printing with Metall

Inkjetprinters accelerate ink impulsively through a thin nozzle. Behind the nozzle a short jet forms and pinches off a droplet. The droplet then impacts onto the paper. We would like to do the same for liquid metal. This is a non-trivial scaling of the original problem as water (ink) and liquid metal have largely different surface tension and density. Further cooling may change the viscosity of the liquid metal and thus affect the shape of the droplet. In this project you will be extending a present experiment and conduct it: the droplet generation will be visualised with stroboscopic and high-speed photography. You will also try to determine the borders of droplet generation through suitable non-dimensional numbers. If all goes well, you may try to simulate the droplet generation and compare with your experiments.

Merging Levitating Droplets

Acoustic Levitation allows to transport droplets without physical contact to a substrate. The working principle is the radiation force in an intense acoustic field which balances gravity. In a simple standing wave field a droplet can be fixed at one location in 3d space, while a phased array allows to change the location of the trap. By this way the droplet may be transported. The idea of this project is to merge two droplets to induce a chemical reaction between the droplets. You will be setting up a standing wave field with multiple traps to levitate and transport two droplets/objects. Upon chemical reaction (which should be violent and exothermic) should be visualized with a high-speed camera.

ACOUSTIC LEVITATION - 3D Mid-Air Acoustic Manipulation (2014)

Requirement: Bachelor or Master in Physics, process engineering, or mechanical engineering
Interest (not knowledge) in experimental work, image processing, numerical simulations, programming and electronics
Hands on attitude!