See the sound a helicopter makes caught on camera
See the sound a helicopter makes caught on camera
As a helicopter flies, a vortex forms at the tip of each of the blades, because there is a difference in pressure between the regions above and below them. The noise is caused by blades hitting the vortices created by their neighbours.
A research team led by Markus Raffel of the German Aerospace Center in Göttingen has developed a technique to take pictures of these vortices.
The method uses the same phenomenon that causes air above road surfaces to shimmer on a hot day. Light rays are bent as they travel through patches of air with different densities, and this can be seen clearly against suitable backgrounds.
A series of experiments using different natural backgrounds revealed that the most successful one for spotting vortices was a quarry in the Harz region of Germany. In this confined space, the helicopter had to be photographed rocking just 10 metres above the ground.
The researchers hope their work will help to make helicopters quieter and less prone to vibration.
Re: See the sound a helicopter makes caught on camera
How it is possible to catch the sound of helicopter.?
Re: See the sound a helicopter makes caught on camera
I have no idea
I got this article from New Scientist and posted here.
I got this article from New Scientist and posted here.
Re: See the sound a helicopter makes caught on camera
Answer is in the article.How it is possible to catch the sound of helicopter.?
The method uses the same phenomenon that causes air above road surfaces to shimmer on a hot day. Light rays are bent as they travel through patches of air with different densities, and this can be seen clearly against suitable backgrounds.
A series of experiments using different natural backgrounds revealed that the most successful one for spotting vortices was a quarry in the Harz region of Germany. In this confined space, the helicopter had to be photographed rocking just 10 metres above the ground.