Application of a novel colour imaging technique to thermal convection under reduced gravity

作者：Heiland H G^*; Wozniak G

来源：Measurement Science and Technology, 2010, 21(12): 125902.

DOI：10.1088/0957-0233/21/12/125902

• fluid flow velocity
• fluid temperature
• liquid crystals
• flow visualization and imaging
• particle image velocimetry
• thermometry
• Marangoni convection
• microgravity

The quantitative measurement performance and the robustness of a novel high-speed imaging system using a liquid crystal tunable filter have been verified by a fluid dynamic experiment in a reduced gravity environment. This new type of diagnostic tool is a combination of a monochrome high-speed CCD camera with fast ferroelectric liquid crystal control. The filter can be tuned to red, green and blue colour planes (RGB filter), which provides real colour images without loss of resolution. The scientific application was the investigation of the influence of buoyancy on the surface tension-driven flow around a bubble on heated wall. The flow velocity and temperature patterns were observed in gravity and microgravity environments. The measuring technique is based on particle image velocimetry and thermometry (PIV/T). The principle of this optical full-field technique relies on seeded thermochromic liquid crystals (TLCs) as signal particles, which change colour depending on their temperature. The experimental results of the flow investigations under 1-g and mu-g conditions are discussed and compared with one another.

• 出版日期2010-12