In the context of this bachelor‘s thesis, an LED-based PIV system was put into operation with the aim of carrying out reflection-free planar boundary layer measurements on a flat wall. In order to evaluate the functionality of the system, measurements were first carried out on a flow past a circular cylinder with a Reynolds number of 3100. The plausibility of the results was verified by comparison with other test and simulation results with similar Reynolds numbers. The test showed that the system is powerful enough to calculate well resolved flow fields in a study area of about 100 cm2. The subsequent boundary layer measurements were carried out on an open channel with a special experimental setup for reflection avoidance. This setup made it possible to avoid reflections near the wall, however this effect was reduced by the deposition of particles on the wall surface. The determined velocity profile was compared with that of the universal law oft he wall and showed good similarities, the profile could be dissolved down to the viscous sublayer. The applicability of the LED-based PIV system for the experiments carried out was confirmed, but quite long light pulses from 100 μs to 200 μs were necessary and some details on the experimental setup for the boundary layer measurement could be further optimized.
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In the context of this bachelor‘s thesis, an LED-based PIV system was put into operation with the aim of carrying out reflection-free planar boundary layer measurements on a flat wall. In order to evaluate the functionality of the system, measurements were first carried out on a flow past a circular cylinder with a Reynolds number of 3100. The plausibility of the results was verified by comparison with other test and simulation results with similar Reynolds numbers. The test showed that the syst...
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