High Speed and Technical Photographs / 4709

Prof. Andrew Davidhazy

Previous Home Next


High Speed Schlieren photograph of a supersonic bullet and its turbulent wake

A bullet flying at almost Mach 1.5 (1.5 times the speed of sound) causes air to be compressed as it pushes its way through "thin air" causing a classic "V" shaped shock wave to appear reminiscent of the "bow" wave of a boat moving on a smooth water surface. The wave, and several trailing sonic events, were made visible by the fact the bullet flew through a Black and White schlieren system where density variations in air caused by air being compressed by the flying bullet cause light rays passing through these regions to pass be intercep[ted by an opaque "knife edge" or to pass by it. This leads to variations in local brightness or density which we then can interpret visually to estimate the various sonic phenomena associated with an object flying at supersonic speed.