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Úvodní aeroelastická měření na profilu se dvěma stupni volnosti
Vlček, Václav ; Luxa, Martin
Jeden stupeň volnosti představuje translační pohyb napříč proudovým polem a druhý stupeň volnosti představuje rotační pohyb okolo osy profilu, umístěné v 1/3 tětivy od náběžné hrany. K visualizaci proudu bylo užito šlírové metody a interferometrie. Obrazy proudových polí byly snímány digitálním fotoaparátem, jejichž příklady jsou součástí této práce.
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Spatial vapour density measurements inside laser induced cavitation bubbles
Hošek, Jan ; Garen, W. ; Shönig, H.
Cavitation bubbles have been studied and reported as an undesirable side effect in many of the medical application used of laser ablation like eye or cardio surgery in recent years. Our intention was to gain a physical information about processes inside the cavitation bubble. We develop a new technique for direct gas/vapour property measurements during the cavitation process in the bubble based on determination of bubble gas density.
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Temperature stabilization of semiconductor lasers for direct measurement of index of refraction of air
Matoušek, Vít
Laser interferometers are even more precise distance measurement devices with resolution in nanometer or sub-nanometer region. If interferometric measurements are carried out under atmospheric conditions (usual situation in industry), they measure optical path length of an unknown distance instead of its true geometrical value. It is caused by an index of refraction of air that introduces a multiplicative constant to measured results. If we want to obtain correct values, the knowledge of the index of refraction is necessary. Generally, the index of refraction can be measured by two ways: indirectly or directly. The first of them is based on parametric analysis of atmospheric properties as: relative humidity, pressure, temperature, concentration of CO.sub.2./sub. etc. Values of these parameters are processed then by Edlén formulas with 10.sup.-7./sup. order [1]. The direct methods are more precise then Edlén formulas (more than 10.sup.-7./sup.) but their practical implementation is more difficult. Devices that directly measure the index of refraction are called refractometers.
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