# Free Software needed to help with Power prediction and stability and match engines

Discussion in 'Software' started by Kapitan_Raider, Nov 24, 2008.

1. Joined: Oct 2008
Posts: 8
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Location: USA

### Kapitan_RaiderJunior Member

Hi All,

I'm a new member and a student and im making a boat. I would like any help on the following:?: :-

The Boat:

V- Planing Monohull
Length: 140ft (waterline)
Beam: 30ft
Draft: 8ft
Displacement(As calculated in Excel using Simpson's Rule): ~660,000lbs
Planing Trim Angle: 3.27deg (while static) Probably be ~ 4 - 4.25deg while planing
See attached Excel Hull Plot to understand better: View attachment 27165

Now the problem is that I need to know the propulsion requirements.

The displacement speed: 16knots
Intended Cruising Speed: 35knots
Intended Cruisng Range Radius @ 35kn: 6,000 miles (so 12,000 total)
"Sprint: Speed for atleast 10 hrs: 55knots
Engines: 2 X Diesel Engines for Cruise + 1 Turbine Engine to get to Sprint Speed; Will rely on 2 X Waterjets for Cruise & 1 Another Waterjet for Sprint

I will be using 2 Lift Stakes also, 1 knuckle but I need to know how and where to place them:?: . I dont know how to get the planing/lifting resistance, wave making resistance nor the skin friction drag. How do i calculate those ? The skin is to be made out of carbon fiber composite. i know that planing lift will be atleast >50% of the total displacement. Also I need the draft at which the boat will start to plane at, at different speeds:?: . The other problem is which engines will I need and how much horsepower for them:?: . Also very important is how do i calculate their fuel consumption to attain my desired range?:?: Once this has been tackled as u may imagine i will also require the weights & dimensions of the engines, their shafts and also the same for the waterjets .

I intend to do all calculations by hand, but any simple software that you know that will help me will also help.
Any and all help and advice will be thoroughly appreciated .

Thankyou & Regards,

Kapitan Raider

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