Author(s): Benjamin Bizjan; Marko Hocevar; Sabina Kolbl Repinc; Gasper Rak

Linked Author(s): GAŠPER RAK

Keywords: Erated flow; Free surface; Laser scanning; LIDAR; Non-stationary surface

Abstract: In this study, a scanning LIDAR device was used to measure a distance to a water column surface subjected to different degrees of aeration. Different flow aeration conditions were attained by variation of air flow rate supplied to the liquid and by changing hole arrangements of the plate that scattered incoming airflow to bubbles. The measurement error was relatively low (5%) in aerated water with 10% -20% volume fraction of air, while much higher in unaerated and highly aerated water (air volume fraction above 20. Interestingly, the bubble size appears to have little effect on the measurement error except in cases with over 50% volume fraction of air where larger bubbles produced lower errors. Despite the measurement uncertainty in ranging of aerated water being by at least an order of magnitude higher than in the case of measuring dry solid surfaces, the LIDAR method is viable for free surface measurement under low to moderate aeration conditions.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0557-cd

Year: 2023