Experimental Analysis of a Thrust Allocation Algorithm for DP Systems Considering the Interference between Thrusters and Thruster-Hull

Formalization of design for physical model of the azimuth thruster with two degrees of freedom by computational fluid dynamics methods

“…It is often referred to as the cross-combination of thrusts [8]; -the presence of cavitation for heavy loads on propellers (intake of air) leads to the decrease in pressure on the propeller blades and can occur at low immersion of the propeller due to the motion of ship across the waves [9]; -extreme conditions with large amplitudes of the motion of the ship perpendicular to the surface of water leads to the sudden drop in thrust and torque with the hysteresis effect [10]; -simultaneous reduction of thrust and reverse thrust can occur due to the interaction between the flow from SP and the hull, caused by the effects of pressure, when the small thrust of SP passes along the hull. This is referred to as the Coanda effect [11][12][13];…”

Thrust allocation algorithm considering hydrodynamic interactions and actuator physical limitations.

“…Computational Fluid Dynamics (CFD) (Cozijn and Hallmann 2012) and model based (Arditti and Tannuri 2012) tests show that hydrodynamic interactions can drastically influence the net thrust. The work presented in Arditti et al (2014) and Arditti et al (2015), with some simplifications in the representation of hydrodynamic interaction, illustrates that by considering these phenomena in the thrust allocation higher reliability and minimization of power consumption can be achieved.…”

“…A review on allocation algorithms is available in Johansen and Fossen (2013). A simple graphical illustration of thrust allocation can be found in Arditti and Tannuri (2012). Further details on the developments of thrust allocation algorithms are presented in the Chapter 3.…”

“…The second one is through CFD calculation, which compared with Particle Image Velocimetry (PIV) measurements provided interesting insight on thruster-hull interactions, as described in Cozijn and Hallmann (2013). The third method is obtaining the data by means of model testes (Arditti and Tannuri 2012).…”

“…The term efficiency curve is used because azimuth thrusters can rotate 360°, and for every angle a different interaction occurs, therefore, the efficiency is defined for different operating angles. The experimental method used in Arditti and Tannuri (2012) was to measure the thrust generated in different azimuth angles ( ( )) and compare it with the bollard pull thrust ( ).…”