[Point1]

Hi All,
I would like to model the effectiveness of a tugboat pulling on the side of a large ship. At the end of the day, I would like to produce a graph of the net force exerted on the ship (assuming they are connected by a rope), vs the distance away from the ship.

I imagine a very simple model of a large, rectangular object (ship) extending well below the free surface, and a cylindrical subdomain, a distance from the side of the "ship" (the axis pointing towards the ship, at right-angles), a couple of metres below the surface. The cylindrical subdomain is to model the thruster of the tug, using a momentum source.

The tug boat can produce a bollard pull of, say 10T.

Depending on the distance away from the ship's side, the wash of the thruster will produce a force on the ship, countering the pull from the rope, eg 2T, which I will monitor from the output. There will then be a net force acting on the ship (8T). This is the quantity that I am after.

I intend to put in an axial momentum source of 10,000kg x 9.8m/s/s divided by the Volume of subdomain m^3

Some other bits of info:
Free surface model
Thruster diameter 1.6m
Thruster distance from ship 2-20m
Ship draft 12m
Ship length - many metres.


Am I over simplifying things here?
The main thing I'm counting on is dissipation of the momentum over a distance.

Awaiting incoming...