Hullspeed analysis - Resistance curve

Hi,
I have run a resistance analysis for a utility boat, and the curve shown was like in the picture below. is it normal if the result like that?if wrong, can anybody tell me what are the source of problem?

 

Looks great . . .

 

is it?before this i compared with the curve of planning (fast patrol boat), its curve was smooth increased.

 

I don't see any obvious flaws. If you are concerned about the local maximum at about 21-22 knots (Fn = 1.1): This is a typical resistance "hump" that many - if not most - planing boats show during the transition from displacement to planing regime. Trim angle will be maximum as well at this point.

It is possible to lower the trim angle with trim tabs or interceptors, which can flatten the hump quite a bit, helping the vessel get on plane more easily.

 

thank you for the explanation. now i understand it..

 

If it is a curve of a 40-45 ft powerboat, it could be credible. In absence of further info about your project - as PAR said...

 

That shape is very typical of a planing boat with a Lp/Bpx of ~3. Go look at the Series 62 data.

 

Take the prediction method You are using and program it Yourself, say in Excel. Then, You will know how it works and if the results are reasonable.

Just pressing the keys in 'black box' software - not for naval architects/engineers.

 

Looks like a reasonable curve for a 10-12 meters planning boat.

LwL= 1/g (V/Fr)²

Regards