Steady State Hydrofoil

Description: This block gives the lift and drag forces acting on the foil, as well as
tangential and normal components of the total hydrodynamic force. The lift-drag characteristic is interpolated from vectors set in the parameters.

Inputs:

Ang Eff --Efective angle of attack (\alpha_e)

Vf  -- Fluid velocity relative to the foil

Outputs:

L -Lift Force (N)

D-Drag Force (N)

N-Force Normal to the Fin (N)

T-Force Tangential to the fin (N)

Parameters:

a- Aspect ratio

Af -area (m^2)

CL(Ang)- Vector of Lift coefficients used for interpolation

Ang  - Vector of angles to use in interpolation

CDO -Drag Coefficient at zero speed

Rho- water density  (kg/m^3)

 

Model Limitations: The lift and drag are interpolated using the above formulae and the table of the coefficient CL passed through the mask as a parameters CL(Ang) and Ang .  This is a symmetric steady state characteristic; there are no memory effects modeled and the outputs follow instantaneous changes of the inputs. The angle at the input to the block is limited to the maximum angle in the vector Ang that defined the CL(Ang.).

Dependency: None. Do not include other MSS blocks are under the mask, and only uses standard Simulink blocks

References: