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Stellar House Science, Inc.

internet data systems
towed systems simulation

Users Manual:

Index Body and Cable Effects
Page 1 Body and Cable Effects
Page 2 General Towing Configuration
Page 3 Cable Element Details
Page 4 Cable Elasticity
Page 5 External Forces
Page 6 External Forces (continued)

External Forces... Continued

T = Tension on umbilical
UT = Tangential component of fluid speed in the cable frame of reference
CT = Tangential drag coefficient of cable
w = virtual cable unit weight
CN = Normal drag coefficient of cable
UN = Normal component of fluid speed in the cable frame of reference
UB = 3rd component of fluid speed in the cable frame of reference (zero in 2-D)
s = Cable scope from the free end For further treatment on the methods used in the simulation, please refer to the references on this website.

Initial Conditions To save processing time, the steady-state (constant-velocity) solution for the cable geometry is calculated using the two differential equations below. The two equations are integrated along the cable scope s starting with initial conditions dT/ds = 0, and T & Angle Phi is given by the endpoint loads on the cable.

Note that the rates of change of tension and cable angle are dependent on only one variable: cable angle.