OrcaFlex User Group 2003 Slide 1 of 10 OrcaFlex - Variable Data Presentation Outline So what is...
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Transcript of OrcaFlex User Group 2003 Slide 1 of 10 OrcaFlex - Variable Data Presentation Outline So what is...
OrcaFlex User Group 2003 www.orcina.com Slide 1 of 10
OrcaFlex - Variable Data
Presentation Outline
• So what is Variable Data in OrcaFlex?
• Which data are variable?
• Hydrodynamic Variable Data
• Load Variable Data
• Externally calculated data
• Structural Variable Data
OrcaFlex User Group 2003 www.orcina.com Slide 2 of 10
OrcaFlex - Variable Data
What is Variable Data?
• Previously, most user defined data was treated as a constant throughout the simulation
• Now, certain data can vary during the analysis - in a pre-determined manner
• These can be as a function of simulation time, or of another variable
• External Functions: Allow interface with user defined external software
OrcaFlex User Group 2003 www.orcina.com Slide 3 of 10
OrcaFlex - Variable Data
Which Data are Variable?
OrcaFlex User Group 2003 www.orcina.com Slide 4 of 10
OrcaFlex - Variable Data
Hydrodynamic Variable Data(1/2)
• Current Direction = F(Simulation time)
• Current Speed = F(Simulation time)
What do these allow me to model?
• Loop currents (change both speed and direction)
• Tidal cycles
• Pre-determined shielding of current
• Horizontal Variation Factor = F(Distance)
OrcaFlex User Group 2003 www.orcina.com Slide 5 of 10
OrcaFlex - Variable Data
Hydrodynamic Variable Data(2/2)
• Drag Coefficient = F(Reynolds No., Re = V.D / )
• Fluid Temperature = F(Water Depth)
• Kinematic Viscosity () = F(Temperature)
• Normal Drag as a function of Re
What do these allow me to model?
OrcaFlex User Group 2003 www.orcina.com Slide 6 of 10
OrcaFlex - Variable Data
Load Variable Data
• Load Force = F(Simulation time)
• Load Moment = F(Simulation time)
• Tension = F(Simulation time)
What do these allow me to model?• Time varying forces & moments on Vessels and 6D
Buoys (use OrcaFlex as a ‘Simulator’)
• Sophisticted winch tension sequences
OrcaFlex User Group 2003 www.orcina.com Slide 7 of 10
OrcaFlex - Variable Data
Structural Variable Data(1/2)
• Axial Stiffness: % Strain vs. Tension
• Bending Connection Stiffness: BM vs. Angle
• Bend Stiffness: Bend Moment vs. Curvature
What do these allow me to model?• Non-linear axial stiffness (for man-made ropes)
• Non-linear Bend Stiffness (esp Bend Limiters)
• Non-linear con. stiffness (Bend Stiffeners)
OrcaFlex User Group 2003 www.orcina.com Slide 8 of 10
OrcaFlex - Variable Data
Structural Variable Data(2/2)
• Expansion Factor = F(Simulation time)
• Payout Rate = F(Simulation time)
• Wing Orientation = F(Simulation time)
What do these allow me to model?• Line thermal expansion effects
• More winch control sophistication
• Control how much lift is generated for ‘birds’
OrcaFlex User Group 2003 www.orcina.com Slide 9 of 10
OrcaFlex - Variable Data
Externally Calculated Data
• User defined external functions
What do these allow me to model?
• User defined software called repeatedly
• Re-calculates value of Variable Data item
• Passes this back for OrcaFlex to use
OrcaFlex User Group 2003 www.orcina.com Slide 10 of 10
OrcaFlex - Variable Data
Conclusion
• General purpose ‘Variable Data’ code architecture
• Powerful functionality for modelling non-constant data
• Extended control over operational sequences