Question Bout Bulb Research... Urgent

[Torrey]

Hi... I want to ask some question about bulbous bow.... hope anyone read this and reply it.... cause it's urgent...
here... i'm doing a reseach about bulbous bow eficiency with a ship model test....
after i got all the resistance of ship model datas.. i kinda confuse .. how to calculate the resistance with include the bulbous bow factor
what i know is.... i can use holtrop formula... but the formula is for the real ship.... n my datas is for the model...
should i scale the boulbous bow first to the real size then use the holtrop formula
or i just can use the holtrop formula with the model's data
-- sorry if my english is hard to understand... i do my best.... n i'm very gratefulll for any information....----
best regards
ToRRey

[jehardiman]

First, seperate the model data into frictional resistance and form resistance. From that you can calculate the effect of the bulb on form resistance (the bulb effect ratio). Then work out the full size resistance using Holtrop-Mennen without the bulb. Extract the full scale frictional resistance to leave the form resistance. Apply the bulb correction from the model data. Reapply the full size frictional resistance including any bulb area.