Ballast system

Can someone tell me the best way to calculate the needed ballast for a cargo 15000dwt and the draft stern.

 

Gm

Fist: You need, as a minimun the hidrostatic and cross curves for that ship.

Second: the cargo condition required.

third: Calculate best performance (Stability, draughts, bending,...etc) combination between fuel, luboil ....., ballast, cargo and other weights in order to obtain, maximun payload, minimun ballast and best seaworthy conditions.

forth: A final optimal condition does not mean a medium good condition. Stability, heeling and draughts must be adecuate during the whole loading/discharging operations.

Harbour operation times and means(cranes, stevedores,....) and loading/discharging rotation must be also taken on account in order to minimize costs.

As you see, there is no simple reply to your question.

Regards

 

thanks for you're answer.