Drag reduction

Instabilities in fluid flows can significantly increase unwanted losses. Thus, more energy is needed to move a vehicle in the surrounding fluid in the presence of the instability waves than without them.

The increase in flow losses can happen in various ways. The instability of the flow can contribute to the onset of turbulence, which is a phenomenon that is extremely challenging to model even today.
The friction losses in a turbulent flow are usually at least one order of magnitude larger than if the flow had remained laminar under similar conditions. Oscillations can not only cause the development of turbulence but can also develop in a turbulent flow too, further increasing the losses.

Our research group has developed techniques that can delay the laminar-turbulent transition in the case of streamlined bodies, thereby reducing flow losses. Among others, we model the effect of elastic coatings and miniature vortex generators, but we also investigate the influence of surface roughness. However, we offer our expertise in any type of flow loss reduction, and we also look for partners to cooperate on various research topics.

You can watch our popular science YouTube video on the topic here.