about boat simulation

hasim

hello

i would like to ask some things about boat simulations, firstly if the software is good enought for the user to calculate the hydrodynamic drag and the results if there are good enought, it would be very good if i can have the advice of a boat expert analist to tell me if he made the simulation and then the real expiriment and how much % different have the results.

i also would like to ask if the people of the shipyards are using simulation software for the design of the hull, or using tables???

i would like to have answers from people that already have expirience, we are going to spent a loto of money on this .

best regards hasim