Consultancy Modelling and Optimization

SQUAT

After the research of depth measurements at Terschelling, depth- and squat measurements by the vessel the Houtvliet in Zeeland has been investigated. The squat is the sinkage of a vessel bij it's speed and depth. The movement of the vessel through the water causes a downwards force. This fenomenon is comparible with the aerodynamics behaviour of aeroplanes in which case there is a upwards force caused by the movement of air along the wings. One part of the research was to analyze an existing squatmodel in the measurement system (Rwslod). This squatmodel doesn't give in all situations a good description of the squat.

The squatmodel has been optimized with measurements. In the figure below the squatmodel is given as a function of the speed of the vessel and the waterway.

On the first Benelux Matlab Usersconference (1997, Amsterdam) a presentation has been given on the subject.

The report 'Advies squat' (september 1997) has been published.

In Matlab software has been developed to prepare and to analyse the measurements and to model squat.

Later by Rijkswaterstaat Directie IJsselmeer some squat researches has been done on the vessels the Markermeer and the Westergat. These vessels are used for depth measurements in the Keteldiep (end of the river the IJssel), where the bottom is polluted.

More information about squat is give on the 'plaatsbepaling'-site of Meetkundige Dienst squatmeasurements.