Largescale free surface measurement for the analysis of ship waves in a towing tank
Abstract
This paper is presenting an optical method for free surface measurement of a stationary flow suitable for largescale experiments in a large towing tank. The new measurement device is based on the projection of laser beams on the surface of the fluid and on the use of a stereoscopic system. The principle of the method is to detect the impact of the laser beams on the air/water interface in order to determine the height of the surface by triangulation for a given number of positions. This method is applied to the measurement of the stationary wave field around a ship model at 1/10th scale. The paper also emphasizes that for low Froude numbers, ((F_{L} = U/√(gL), where U is the ship velocity and L the ship length), the effects of the scale on the flow characteristics are limited. These scale effects are studied by comparison with measurements taken in a smaller towing tank around the same ship model at scale 1/77.5. The free surface and the velocity field near the hull at the two scales are compared.
 Publication:

Experiments in Fluids
 Pub Date:
 October 2015
 DOI:
 10.1007/s003480152054z
 Bibcode:
 2015ExFl...56..184G
 Keywords:

 Laser Beam;
 Free Surface;
 Froude Number;
 Laser Sheet;
 Camera Model