Catamaran Resistance and Propulsion Calculations
Budget: $10 – $30 USD
I have a catamaran design that is almost through the preliminary stage, yet I still need a solid set of resistance and propulsion figures before we freeze the lines plan and commit to engine selection. All key hull-form parameters (LOA, beam, Cp, prismatic distribution, etc.) as well as speed-versus-RPM tank-test data are on hand, so you can jump straight into the hydrodynamic work without hunting for basics.
Your task is to calculate total calm-water resistance across the operating speed range, break it down into the usual components (frictional, residual, air, appendage, correlation allowance), and then size the required propulsion power with a clear allowance for hotel loads and service margins. I’m happy for you to use CFD (OpenFOAM, ANSYS Fluent) or well-established empirical methods such as Holtrop-Mennen, Savitsky or Michlet—just be explicit about assumptions, coefficients and calibration steps.
Deliverables
• Calculation file or script (Excel, Python, MATLAB, or similar) showing all inputs, formulas and step-by-step results
• Brief technical note (PDF or DOC) summarising methodology, resistance curve, propulsive power curve and key sensitivities
• One-page summary table suitable for inclusion in our design report
Acceptance criteria
• Results reproduce within ±3 % when I rerun your file with the same inputs
• All symbols, units and references are clearly identified
• Power figures account for both calm-water and 10 % sea margin
With accurate resistance data in hand, I can move directly to propeller and engine selection, so clarity and traceability are more valuable to me than flashy graphics. If you need anything beyond the hull geometry and speed measurements, just tell me up front and I’ll provide it.
Your task is to calculate total calm-water resistance across the operating speed range, break it down into the usual components (frictional, residual, air, appendage, correlation allowance), and then size the required propulsion power with a clear allowance for hotel loads and service margins. I’m happy for you to use CFD (OpenFOAM, ANSYS Fluent) or well-established empirical methods such as Holtrop-Mennen, Savitsky or Michlet—just be explicit about assumptions, coefficients and calibration steps.
Deliverables
• Calculation file or script (Excel, Python, MATLAB, or similar) showing all inputs, formulas and step-by-step results
• Brief technical note (PDF or DOC) summarising methodology, resistance curve, propulsive power curve and key sensitivities
• One-page summary table suitable for inclusion in our design report
Acceptance criteria
• Results reproduce within ±3 % when I rerun your file with the same inputs
• All symbols, units and references are clearly identified
• Power figures account for both calm-water and 10 % sea margin
With accurate resistance data in hand, I can move directly to propeller and engine selection, so clarity and traceability are more valuable to me than flashy graphics. If you need anything beyond the hull geometry and speed measurements, just tell me up front and I’ll provide it.