•transformation of arbitrary wave trains from sta- tionary positions to other arbitrary positions, es- pecially
•upstream transformation to the wave board to get the corresponding wave maker signal, and
•generation of a all kinds of deterministic wave trains,
•transformation of arbitrary wave trains from sta- tionary positions to a moving reference frame of a cruising structure。
The modified non-linear approach is fast and precise and applicable in day-to-day use for experimental inves- tigations。 The method can be adapted easily for new requirements as the implementation of different wave theories is possible。
scale or arbitrary synthesized wave trains, e。g。 from op- timization processes can be used。 The potential of the procedure is demonstrated by simulating different wave scenarios like wave packets, irregular and regular seas with embedded wave packets。
Furthermore, the method allows the transformation of given wave sequences into the moving reference frame
of a cruising vessel。 With this technique wave scenarios
can be analyzed from the point of view of a sailing ship。
A wide range of applications of the presented non-linear wave calculation procedure is given:
Validation of a numerical wave tank based on po- tential theory in combination with a Finite Element Method
•Validation of a numerical wave tank using a
RANSE code and a dynamic mesh approach
•Experimental investigation of seakeeping charac- teristics of offshore structures
Experimental investigation of intact stability and
comparison with numerical simulations
Both numerical wave tanks provide detailed knowledge of the pressure, velocity and acceleration fields in the entire fluid domain。 This information can be used in a next step to investigate wave/structure interaction。
Recapitulating, the modified non-linear theory is a pow- erful tool to face the complex tasks related to the ex- perimental investigation of extreme structure behaviour such as large rolling, capsizing, and rogue wave impacts。
In conclusion, the modified non-linear theory is an ex- cellent tool to generate deterministic wave trains at ar-
wave at ship (movi ng reference frame)
180 190 200 210 220
t [s] 230 240
capsiz ing of the Ro Ro vessel
18 0 19 0 20 0 21 0 220 230 240
bitrary positions (even in a moving reference frame) as
this is the only procedure which can calculate upstream to determine wave board motions and the associated control signals。 In calculating the wave elevation down- stream, the above method agrees well with the numer- ical wave tanks based on potential theory/ FEM and RANSE/ VOF (Fluent)。 Thus, the additional capabil- ities of numerical wave tanks, i。 e。 the determination of wave field characteristics (velocity, acceleration and pressure fields) and of the RANSE/ VOF method (con- sideration of wave breaking) can be ideally combined