Holographic particle-image velocimetry in the first International Microgravity Laboratory aboard the Space Shuttle Discovery

Abstract

In January 1992 the Space Shuttle Discovery carried the first International Microgravity Laboratory into Earth orbit for eight days. One of the many experiments carried out during the orbit was a combined study of triglycine sulfate crystal growth from solution and fluid-particle-dynamics studies in microgravity. Optical diagnostics included holocameras to provide concentration measurements and three-dimensional particle tracking. More than 1000 holograms that were recorded in space have been analyzed since the flight, providing a wide range of interesting conclusions about microgravity, crystal growth, and particle dynamics. This paper focuses on the results of holographic particle-image velocimetry experiments and provides an excellent example, along with new techniques, for exploiting holography for particle and flow diagnostics.

Holografía: ciencia, arte y tecnología

“…Permite estudiar desde aerosoles hasta el plancton marino e incluso se ha utilizado para analizar la dinámica de partículas microscópicas y el crecimiento de cristales en condiciones de microgravedad mediante experimentos realizados a bordo del trasbordador espacial Discovery en los que se registraron más de mil hologramas [50].…”

Holgraphic research outside the Earth in the 21st century: trends and prospects

“…Crystal growth mechanisms in a low-g environment were studied. [52][53][54][55][56][57] The holograms were processed later on Earth and crystal growth rates were evaluated after the flight. None of crystal growth experiments aboard Spacelab 3 were performed in situ in real time.…”

An integrated optical set-up for fluid-physics experiments under microgravity conditions

“…The most critical point for the introduction of holographic interferometry into space equipment is the recording medium. High-resolution photographic films have been used for example in the first International Microgravity Laboratory (IML-1) [3]. Nevertheless, films cannot be analysed for real-time investigation since they require a wet-chemical development.…”

“…Holography allows one to record dynamically the reference state of the test object; holographic methods allow one to follow the change of a beam shape over a substantially larger range than does direct interferometry. Holography and holographic interferometers have already been used in space [3,4] but with restrictions due to the hologram-recording-medium limitations. Indeed, the choice of the recording material is the key point: silverhalide films require a wet process that is quite difficult to implement under space conditions; thermoplastic films need heavy surrounding hardware.…”