Propulsion of a ship deals with the final balance between resistance (friction, pressure and free-surface), propulsion forces and its inherent interaction. And often so-called Energy Saving Devices (or ESDs) are also present increasing (hopefully) the efficiency of this complex system. With ReFRESCO it is possible to analyze the complete propulsion of any system, using different fidelity levels for the modelling of the propulsion unit (propeller): 1) a simple actuator-disk; 2) a coupling to a potential-flow BEM code; 3) a quasi-steady “frozen-rotor” approach; 4) the most accurate sliding-grids approach. But the accuracy achieved for all the issues intervening in the propulsion chain (friction, pressure, free-surface, propulsion loads) is of extreme importance. Several V&V studies have been done in the past on all these issues before reaching an acceptable accuracy (less than 5% for all issues!). See http://www.refresco.org/publicationscases/allpublications/ for several publications on all these issues, and also the other Case sections on propellers and steady wave free-surface. Some examples of relevant studies can be seen below.

 

KVLCC2 Studies on Resistance Prediction

Propulsion5 Propulsion4

Tokyo Workshop JBC study on Propulsion (ship, propeller, ESD and free-surface)

Propulsion2 Propulsion3

Studies on ESDs and Interaction Effects

Propulsion1