Home > Version History > What was New in Version 4.3
What was new in Version 4.3
Predefined 3D surfaces shapes : Predefined shapes such as planes, boxes, cylinders and surfaces of revolution are now available to easily set-up rigid surfaces such as bellmouths or mid-water arches for example. These predefined shapes are directly available from the Drawing tab of Rigid Bodies and avoid having to define all nodes and triangle elements in a separate text file.
Zones Study Post-Processing : The Zones Study module directly produces maximum or alternated values of selected results variables (such as tension, curvature or deviation angles at connections) along user-specified zones on the risers for series of analyses. This module is now available through batch commands and has been moved into the Model Browser to allow for multiple requests. These changes significantly ease the automation of cumbersome post-processing tasks required with unbounded flexible risers.
Reaction forces post-processing : Reaction forces at nodes and connections of any lines or support vessels can now be calculated and displayed within the GUI. Time-history, snapshots and envelopes of reaction forces and moments variables can now be plotted directly using the main post-processing window.
Contact loads and energy : Post-processing of contacts loads is now available in the GUI and includes new variables such as contact energy, normal reaction force, friction forces, trench induced resistance and friction induced torsion moment. Post-processing of these contact loads allows for instance to easily derive the impact energy when two lines clash.
Lateral friction model with trenches : The lateral friction force model has been improved to include the additional peak resistance loads exerted along the line when embedded in a trench. Trench geometrical properties such as depth, bottom and upper width together with associated lateral resistance loads characteristics can be defined from the Contact Type window.
Friction induced torsion moment : The moment induced by friction forces applied at the contact point on the outer diameter of lines can now be included in the analyses. This moment can be activated from the calculation parameters window for any analysis.
External fluid of lines : Whereas the internal fluid of lines could be fully defined and even varied over the time, the external fluid could only be seawater. The external fluid can now be optionally set different than seawater. The external fluid is used to derive the submerged weight of pipe and the external pressure used to calculate the true wall tension and resulting stress outputs for rigid pipes. The default external fluid of course remains seawater as defined in the Sea & Ground model component and there will be no need to change anything to existing models when not strictly required. Setting external fluids at will allows to define pipe-in-pipe models including internal and external pipes which interact through contact loads.
Buoyancy Modules Properties : Buoyancy module properties can be defined independently from the Buoy object and be used as simple loads for any type of model component. Typical application of these properties is definition of concentrated mass, drag or lift coefficients, and net buoyancy forces along lines. These properties also offer the possibility to easily set-up distributed loads and check-out the impact of various buoyancy modules spacing along flexible risers or export lines.
Spectral analysis results plotting module : This new spectral analysis post-processing module allows to plot response spectrum and RMS values for any results derived from time-domain simulations. Response spectrum and RMS values are calculated using direct Fourier transform and cross-spectrum analysis. Response spectrum gives the frequency contents of time-domain signals which better characterizes the response of the riser system and allows identification of resonances and most critical excitation periods.
Improvements to non-linear bend stiffener : The non-linear bend stiffener component used to simulate the effect of non-linear PU material behavior laws previously had to be used with the advanced bend-stiffener model which considered the interaction between the flexible pipe and the stiffener cone through contact elements. This model allowed modeling of gaps inside the stiffener but boundary conditions used with this advanced model unfortunately tended to alter the results obtained when combined with the non-linear PU material laws. This problem has been corrected in the GUI and non-linear PU material laws can now be combined with the equivalent bend-stiffener elements. Testing demonstrated that results for non-linear bend stiffener are now fully consistent with those obtained with other industry leading bend-stiffener design software.
3D View Parameters Window : A new window has been added which gives direct access to all 3D view parameters, such as azimuth and elevation angles, center point and zoom ratio. This allows to set-up all view parameters by-hand and save the current view as the default view. This new window can be displayed by right-clicking over the main 3D View window and selecting the Edit View Parameters item from the pop-up menu. Parameters of the current view can also be saved by selecting the Set As Default View item and recalled at a latter stage by calling the Go To Default View feature.
Hydrodynamic coefficients (solver only) : Drag and added mass coefficients used to calculate hydrodynamic loads along lines can now be set variable as a function of Reynolds number, water depth or position along the line and heading for non-circular sections. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
Static thermal loads (solver only) : Thermal loads applied along lines could be defined within time-domain dynamic analyses only. Temperature profiles and resulting thermal loads can now be defined also as a function of quasi-static analyses steps. All inertia effects are of course cancelled for these analyses with avoids going through the time-integration process when not strictly needed. Using dynamic thermal loads instead of quasi-static ones however offers more stability to the calculation as required to predict post-buckling behavior.
Static Quick-Connect-Disconnect (solver only) : The quick-connect-disconnect feature used to simulate the disconnection of turrets or line ends has been improved. This feature was previously available with time-domain dynamic analyses only and has been extended to quasi-static analysis. Any boundary condition can therefore be modified at predefined steps during incremental static analyses. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
Quasi-static winches (solver only) : Winches were available with time-domain dynamic simulations only. This allowed to define controlled length of spring connecting the end node of a line with a support vessel for instance and thus carry out dynamic installation analyses. Winches may now alternatively be defined within static analyses. In this case, the reference length may change as a function of the static step which allows to carry out static installation analyses. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
Low frequency motions for frequency domain analysis (solver only) : The solution method used with frequency domain dynamic analysis has been extended so as to include the effect of low frequency motions in addition to wave frequency motions. Considering such low frequency motions is for instance required when running some mooring analyses of coupled systems. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
Elasto-plastic law for rigid pipes (solver only) : Non-linear elasto-plastic strain/stress relationships can be used to simulate the behavior of rigid pipes submitted to high curvature levels. The bending moment and axial loads are derived from integration of the strains over the pipe circumference and the plastic component is evaluated through a return mapping algorithm. This new feature allows for instance to simulate non-linear reeling of rigid pipes.
Interpolation of RAOs function of draft (solver only) : Motions RAOs and hydrodynamic characteristics of vessels can now be automatically chosen by the solver depending on the actual draft. The solver may interpolate the contents of several hydrodynamic database files (.HDB) associated with given draft values to match with the expected hydrodynamic properties for the actual draft. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
Reading of mooring files (solver only) : Mooring files are text files produced by the solver which are required to carry out quasi-static mooring simulations. These file contains the relationship between tension at the fairlead points and vessel excursion. They are read by mooring analyses software such as DIODORE to determine the reaction forces due to mooring lines without requiring to calculate the shape of the mooring line. These files can now in turn be read by the solver which allows much faster simulation of mooring systems in the time-domain. This new feature is available in the solver only through dedicated keyword and shall be implemented within the GUI for a future release.
