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General Wave-Frequency Vessel Motions Questions (Discsim, Semisim, Shipsim)

General Editor-Related Questions

Single-Point "Mooring" Questions (CALMsim, SPMsim, Towsim)

General Spread Mooring-Related Questions

General Model Test-Related Questions

Mooring and Riser-Related Questions

Loss of nonlinear mooring response with user-specified periods and damping

Sway-yaw motions predicted in aligned environmental conditions?

Definition of Surge direction in CALMsim?

CALMsim "synchronization error" messages?

Reports of "INF" for loads and motions in CALMsim?

Meaning of "Nonzero IER = 2" warning?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Persistent non-zero mean heading for turret FPSO in waves only?

Clarification of "low sway-yaw mode" outputs in LOWOUT?

Missing output for angular values for the legacy "low sway-yaw mode" in LOWOUT?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

How to simulate a nonzero moment on a symmetric vessel (buoy or spar)?

Mooring Feedback for Stand-Alone CALM Buoys

Stand-alone CALM buoy motions corrected for wave-frequency mooring line loads?

Semi-submersible or shipshape motions corrected for wave-frequency mooring line loads?

Mooring feedback in wave-frequency dynamics for Moorsim/Sparsim/TLPsim?

Differing MEANOUT load values depending on setting of nodal load option?

Location on vessel of applied forces in "continuous equilibrium" offsets?

Meaning of roll, pitch, yaw for large-amplitude motions?

Bizarre "continuous equilibrium" results in Catsim?

Vertical Translation warning in Catsim?

Treatment of trim and heel in simulations?

Global versus Vessel stiffness matrix resolution in Catsim?

Achieved stiffness matrix precision?

"Continuous equilibrium" Catsim offsets for TLP?

Mooring stiffness matrix in Catsim; unconventional row/column ordering?

Handling of large-angle offsets in Catsim "Continuous Equilibrium" offset?

Catsim "Hand of God" offsets from non-equilibrium starting point?

Cross-platform compatibility of binary data files (CATDAT, etc.)?

Meaning of "acceleration" output variable in Shipsim and Semisim?

Mooring Feedback for Stand-Alone CALM Buoys

Limits to per-run wave directions for RAOs in Shipsim/Semisim/Discsim?

Semisim: Best to use regular wave height or slope for RAO generation?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Loss of nonlinear mooring response with user-specified periods and damping

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Calculation of snapshot vessel positions and low-frequency line loads in Moorsim

Wholly new vessel & mooring system: datafile creation strategies?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

Mooring Feedback for Stand-Alone CALM Buoys

Azimuthally symmetric system fails to exhibit azimuthally symmetric output?

Version 5.5+ Normal Mode Model discussion?

Smaller line loads with v 5.5+ normal mode model?

Legacy Low-Frequency correlation model flag?

S.L.O.R. handling of risers in Moorsim?

Moorsim "line on bottom" shows negative values?

Wildly different interpolation table for similar lines?

Unreasonably large wave-frequency load variations?

Longitudinal strain waves in mooring lines; internal damping neglected?

Anchor load discrepancy between RANOUT and XCLDAT?

Failure of XCLDAT to be produced; due to interpolation table error messages?

RelBow, RelMoon and RelMoorCentr in XCLDAT; what are they?

Stand-alone CALM buoy motions corrected for wave-frequency mooring line loads?

Semi-submersible or shipshape motions corrected for wave-frequency mooring line loads?

XCLDAT "relative motion" Wave-Frequency max/min/mean values in SPMsim and Moorsim?

User-specified roll damping and wave drag connection?

Lazy Wave Rider interpolation table anomaly?

SPMsm problematic single line mooring with slack-tethered surface buoy.

Crossed seas and low-frequency response: wave drift force estimation...

Low-frequency envelope asymmetry...

Comparison of Moorsim low-frequency motion statistics and peaks: legacy versus non-legacy?

Inconsistent fairlead location warning?

Moorsim disagreement between "snapshot" mooring loads in SNAPOUT/LOWOUT/XCLDAT?

Asymmetry reversal of +/- RMS and +/- peak amplitudes in LOWOUT?

Unusual tension-offset behavior when using LINE_STRAIN_DB.txt?

Underestimated current loads on lines in LOWOUT?

Nonsensical mean line loads in MEANOUT for neutrally buoyant lines and low pretension?

"Dimensionless" RAOs for use in USERRAOS.txt...

Single mooring line considerations.

SeaSoft coordinate origin for non-fore-aft-symmetric vessels?

Failure of expected Sparsim/Moorsim/TLPsim output symmetry in a rotated environment.

Sign reversal in wave drag (aka absorption) coefficients in Slowsim/Moorsim?

Sign reversal in wave drag on a column with waves running upstream into a current?

Help with importing old datafiles into recent applications.

Waterline beam and length values for semisubmersibles?

Current forces on semisubmersibles in Moorsim?

Yaw Moment arm used for wind and current forces?

Aligned legacy and non-legacy low-frequency RMS motion disagreement.

How many interpolation layers for deepwater applications in Moorsim and SPMsim?

Moorsim: "Expanded frequency grid for cross-correlation integration"?

User forces on moorings in Moorsim?

Equilibrium failures in Moorsim

LOWOUT reported current loads on lines and risers.

Differences in SEMISUM between Sparsim and Semisim?

Vessel motions arising from combined independent wave trains.

Differing MEANOUT load values depending on setting of nodal load option?

Discussion of "Hinge_Motn.stxt" output file?

Zero values for some angular variations "Hinge_Motn.stxt" output file?

"Ball Hinge" definition in Moorsim motion support files SHIPRAO.stxt, SHIPRAN.stxt?

Missing Hinge-Motion.stxt file?

SPMsim and Moorsim with steady environmental forcing fails to terminate normally.

SPMsim vs Moorsim for locked turret evaluations.

Mooring stiffness in MEANOUT doesn't match stiffness in LOWOUT for "legacy" Sparsim/TLPsim runs?

Azimuthal symmetry of semisubmersible drift coefficients for yaw?

Member length for water-piercing members?

Wholly new vessel & mooring system: datafile creation strategies?

Meaning of "Relative Motion" variable?

Best current force model for semisubmersibles?

Meaning of "member dimension" for Semisim member specification?

Meaning of "acceleration" output variable in Shipsim and Semisim?

How to use Semisim for TLP wave-frequency RAOs?

Meaning of "Utilize ONLY square law driving forces" option for semi-type vessels?

"Full square-law driving force calculation" produces unusually small heave damping in Sparsim?

RAO phases in Semisim differ for three damping options?

Submerged buoy pitch and roll period differences: Sparsim vs Semisim?

Limits to per-run wave directions for RAOs in Shipsim/Semisim/Discsim?

Sign reversal in wave drag on a column with waves running upstream into a current?

Agreement between quoted damping levels and RAO peaks in Semisim?

Waterline beam and length values for semisubmersibles?

Current forces on semisubmersibles in Moorsim?

Aligned legacy and non-legacy low-frequency RMS motion disagreement.

Moorsim: "Expanded frequency grid for cross-correlation integration"?

Semisim non-agreement of two heave RAOs with identical damping.

Semisim: Best to use regular wave height or slope for RAO generation?

Regular wave "slope" versus "height" specification: Different output for identical input?.

LPP versus LWL in vessel definition?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Insensitivity of roll damping to bilge keel particulars?

Problems with motion RAOs with nonzero vessel speed?

Maximum value estimates for wave-frequency variables?

Meaning of "Relative Motion" variable?

Meaning of "acceleration" output variable in Shipsim and Semisim?

Limits to per-run wave directions for RAOs in Shipsim/Semisim/Discsim?

Inconsistency in XCLDAT "Gy" wave-frequency RMS and that reported by SHIPRAN.stxt?

Anomalous surge response and encounter period in Shipsim with forward motion and following seas?

Use of SeaSoft damping estimates in conjunction with USERRAOS.txt?

SeaSoft coordinate origin for non-fore-aft-symmetric vessels?

Semisim: Best to use regular wave height or slope for RAO generation?

Help with wave-frequency damping interpretation.

Node_Motn.stxt wave-frequency fairlead motion; disagreement with SHIPRAN.stxt?

Wave drift force spectrum: Defined frequency range?

Azimuthal asymmetry of wind and current forces for spars?

Forward speed versus current in Slowsim?

Missing mean wave absorption force frequency distribution in Slowsim?

Differences in mean environmental loads between TLPsim/Sparsim and Slowsim?

Mass units in Slowsim output stream?

Problematic integration checks of wave absorption ("drag") forces in Slowsim...

Slowsim: Strange TLP wave drift coefficients in aligned current?

Bizarre wave reflection coefficients for tanker and semisubmersible in the presence of current?

Intergroup Spacing for wind and current speed and force/moment spectra in Slowsim?

Missing current loads on lines in Slowsim?

Water Depth/Draft "Ratio" versus "Parameter"?

"Attack Angle" versus "Relative Heading" in Slowsim?

Inconsistent choices for angular variable in Slowsim output tables?

Error in Slowsim "VIIr. Net Spectral Values: Wind, Wave, Current" tables?

Current corrections for user-supplied wave drift coefficients (DRFTCOFS.txt)?

Sign reversal in wave drag (aka absorption) coefficients in Slowsim/Moorsim?

Member length for water-piercing members?

How do I set TLP tendon lengths?

Mixed vertical and conventional catenary lines?

Constant-tension riser simulation?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Current and wind vertical area centroids for Sparsim?

Best current force model for semisubmersibles?

Azimuthal asymmetry of wind and current forces for spars?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

Meaning of "Utilize ONLY square law driving forces" option for semi-type vessels?

How to simulate a nonzero moment on a symmetric vessel (buoy or spar)?

Vertical area centroids and pitch/roll moments; relationship?

"Peak Factor Multiplier" behavior with "Auxiliary External Forcing" option?

"Full square-law driving force calculation" produces unusually small heave damping in Sparsim?

Best treatment of moonpool and soft tank water for spars?

Azimuthally symmetric system fails to exhibit azimuthally symmetric output?

Version 5.5+ Normal Mode Model discussion?

Smaller line loads with v 5.5+ normal mode model?

Submerged buoy pitch and roll period differences: Sparsim vs Semisim?

Sparsim & TLPsim large oscillations about a small offset: anomalous pulldown?

Legacy Low-Frequency correlation model flag?

TLPsim equilibrium search failures?

TLPsim & Sparsim; requesting current loads on lines effects mean wave loads?

TLPsim & Sparsim; forces acting on moorings lost in LOWOUT?

Anchor load discrepancy between RANOUT and XCLDAT?

RelBow, RelMoon and RelMoorCentr in XCLDAT; what are they?

Differences in mean environmental loads between TLPsim/Sparsim and Slowsim?

XCLDAT "relative motion" Wave-Frequency max/min/mean values in SPMsim and Moorsim?

Lazy Wave Rider interpolation table anomaly?

Moorsim disagreement between "snapshot" mooring loads in SNAPOUT/LOWOUT/XCLDAT?

Failure of expected Sparsim/Moorsim/TLPsim output symmetry in a rotated environment.

Sign reversal in wave drag (aka absorption) coefficients in Slowsim/Moorsim?

Sign reversal in wave drag on a column with waves running upstream into a current?

Current forces on semisubmersibles in Moorsim?

Yaw Moment arm used for wind and current forces?

Is TLPsim missing pitch and roll "normal mode" pages in LOWOUT.stxt?

How many interpolation layers for deepwater applications in Moorsim and SPMsim?

Differences in SEMISUM between Sparsim and Semisim?

Differing MEANOUT load values depending on setting of nodal load option?

Discussion of "Hinge_Motn.stxt" output file?

Zero values for some angular variations "Hinge_Motn.stxt" output file?

"Ball Hinge" definition in Moorsim motion support files SHIPRAO.stxt, SHIPRAN.stxt?

Missing Hinge-Motion.stxt file?

Mooring stiffness in MEANOUT doesn't match stiffness in LOWOUT for "legacy" Sparsim/TLPsim runs?

Non-vanishing wave-frequency Z turret moment?

Non-vanishing low-frequency Z turret moment with trim or heel?

Non-equilibrium orientation warning with a turret?

SPMsim Low-Frequency surge direction definition?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Sway-yaw motions predicted in aligned environmental conditions?

Problems with motion RAOs with nonzero vessel speed?

RAOs: Vessel speed specification treatment?

Definition of Surge direction in CALMsim?

CALMsim "synchronization error" messages?

Meaning of "Nonzero IER = 2" warning?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Calculation of snapshot vessel positions and low-frequency line loads in SPMsim

Persistent non-zero mean heading for turret FPSO in waves only?

Clarification of "low sway-yaw mode" outputs in LOWOUT?

Missing output for angular values for the legacy "low sway-yaw mode" in LOWOUT?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

"Select alternate equilibrium" flag; produces unexpectedly large loads?

Differing peak amplitude factors for variable current, wind and waves?

Trim and heel warning message purpose and meaning?

VFz and VFz+ meaning and differences in XCLDAT?

LOWOUT and RANOUT disagreement on maximum quasi-static line tensions?

Unreasonably large wave-frequency load variations?

Failure of XCLDAT to be produced; due to interpolation table error messages?

SPMsim turret moments; LOWOUT versus SNAPOUT discrepancy?

Modal stiffness definition for legacy high sway-yaw mode?

RelBow, RelMoon and RelMoorCentr in XCLDAT; what are they?

XCLDAT "relative motion" Wave-Frequency max/min/mean values in SPMsim and Moorsim?

User-specified roll damping and wave drag connection?

SPMsm problematic single line mooring with slack-tethered surface buoy.

"Legacy" versus "Non-Legacy" handling of user-specified low frequency damping in SPMsim?

Execution failures in SPMsim with "Non-Legacy" normal mode processing?

Differences in "Legacy" and "Non-Legacy" SPMsim output for aligned conditions?

Change in SPMsim legacy low sway-yaw mode peak amplitudes at version 5.5x?

Elliptical bounding box functionality lost in SPMsim?

Crossed seas and low-frequency response: wave drift force estimation...

Change in equilibrium "surge" offset sign in SPMsim?

Inconsistent fairlead location warning?

Moorsim disagreement between "snapshot" mooring loads in SNAPOUT/LOWOUT/XCLDAT?

Changes in SPMsim "legacy" sway-yaw normal mode periods between versions 5.4 and 5.5?

Legacy versus Non-Legacy normal mode periods in SPMsim?

Legacy flags in SPMsim; version 5.47 versus v 5.53...

User-specified versus simulation-chosen dynamic heading control spring constant in SPMsim...

Single mooring line considerations.

Version 5.5+ normal mode decomposition for SPMsim; yaw reporting in LOWOUT?

Help with importing old datafiles into recent applications.

Large differences in SPMsim's low-frequency yaw between "legacy" and "non-legacy" treatments?

Node_Motn.stxt wave-frequency fairlead motion; disagreement with SHIPRAN.stxt?

Vessel motions arising from combined independent wave trains.

Differing MEANOUT load values depending on setting of nodal load option?

Discussion of "Hinge_Motn.stxt" output file?

Zero values for some angular variations "Hinge_Motn.stxt" output file?

"Ball Hinge" definition in Moorsim motion support files SHIPRAO.stxt, SHIPRAN.stxt?

Missing Hinge-Motion.stxt file?

SPMsim and Moorsim with steady environmental forcing fails to terminate normally.

Which SeaSoft titles does Squallsim support?

When should (and why would) I "Force-rebuild all support data"?

Avoiding unnecessary re-computation of Squallsim's support tables?

What kinds of input changes require a rebuild of support data?

Wave drag on semi-submersibles in Moorsim?

Appearance of "LCG-to-Midships distance" in version 6.50 vessel parameters?

"td_aux" directory, RanTable.txt, *.sqsm, etc.?

Squallsim files to submit for support requests?

Inscrutable UPPER CASE ERROR MESSAGES?

Where to find SeaSoft's excursion diameter estimate.

Confused by "default" fairleads, "selected" fairleads and "lines for dynamic evaluation"?

"Time-Domain Support Resources" block in "Diagnostics.stxt?"

Schizophrenic "duration" of time domain simulation?

TD_WFlineStatsOut.stxt methodology & motivation?

Discussion of TD_Statistics.stxt data & relationship to TD_WFlineStatsOut.stxt?

Erratic time steps in TD_History_Out.stxt?

Member length for water-piercing members?

How do I set TLP tendon lengths?

Mixed vertical and conventional catenary lines?

Constant-tension riser simulation?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Best current force model for semisubmersibles?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

How to use Semisim for TLP wave-frequency RAOs?

Meaning of "Utilize ONLY square law driving forces" option for semi-type vessels?

Interpolation layer strategies for TLPsim?

"Continuous equilibrium" Catsim offsets for TLP?

Vertical area centroids and pitch/roll moments; relationship?

Azimuthally symmetric system fails to exhibit azimuthally symmetric output?

Inertial correction for TLP tendons?

Version 5.5+ Normal Mode Model discussion?

Smaller line loads with v 5.5+ normal mode model?

TLP in quartering conditions; symmetric wave drift/drag loads?

Sparsim & TLPsim large oscillations about a small offset: anomalous pulldown?

Legacy Low-Frequency correlation model flag?

TLPsim equilibrium search failures?

TLPsim & Sparsim; requesting current loads on lines effects mean wave loads?

TLPsim & Sparsim; forces acting on moorings lost in LOWOUT?

RANOUT output files missing for TLPsim?

RelBow, RelMoon and RelMoorCentr in XCLDAT; what are they?

Differences in mean environmental loads between TLPsim/Sparsim and Slowsim?

XCLDAT "relative motion" Wave-Frequency max/min/mean values in SPMsim and Moorsim?

Apparent disagreement for TLP "snapshot load offsets" in LOWOUT?

Moorsim disagreement between "snapshot" mooring loads in SNAPOUT/LOWOUT/XCLDAT?

Slowsim: Strange TLP wave drift coefficients in aligned current?

Failure of expected Sparsim/Moorsim/TLPsim output symmetry in a rotated environment.

Sign reversal in wave drag (aka absorption) coefficients in Slowsim/Moorsim?

Sign reversal in wave drag on a column with waves running upstream into a current?

Current forces on semisubmersibles in Moorsim?

Yaw Moment arm used for wind and current forces?

Is TLPsim missing pitch and roll "normal mode" pages in LOWOUT.stxt?

How many interpolation layers for deepwater applications in Moorsim and SPMsim?

Differences in SEMISUM between Sparsim and Semisim?

Differing MEANOUT load values depending on setting of nodal load option?

Missing Hinge-Motion.stxt file?

Mooring stiffness in MEANOUT doesn't match stiffness in LOWOUT for "legacy" Sparsim/TLPsim runs?

Sway-yaw motions predicted in aligned environmental conditions?

Definition of Surge direction in CALMsim?

Meaning of "Nonzero IER = 2" warning?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Persistent non-zero mean heading for turret FPSO in waves only?

Clarification of "low sway-yaw mode" outputs in LOWOUT?

Missing output for angular values for the legacy "low sway-yaw mode" in LOWOUT?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

LPP versus LWL in vessel definition?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Insensitivity of roll damping to bilge keel particulars?

Loss of nonlinear roll RAOs with user specified roll period and damping?

Meaning of "encounter period" with nonzero vessel speed?

Maximum value estimates for wave-frequency variables?

Meaning of "Relative Motion" variable?

Missing multiple wave heading option for comprehensive simulations?

Vessel deadweight data in "Tanker Help" facility lost on program termination?

How to accomplish "Batch" runs using SeaSoft?

Zero up-cross periods for accelerations?

Limits to per-run wave directions for RAOs in Shipsim/Semisim/Discsim?

Reference origin for angular RAOs in USERRAOS file?

Phase conventions in Shipsim/Semisim/Discsim?

Angular RAOs in Shipsim/Semisim/Discsim versus WAMIT...

"Dimensionless" RAOs for use in USERRAOS.txt...

Anomalous surge response and encounter period in Shipsim with forward motion and following seas?

SeaSoft coordinate origin for non-fore-aft-symmetric vessels?

Constant wave slope versus constant wave height in SeaSoft RAO estimates.

LPP versus LWL in vessel definition?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Loss of nonlinear roll RAOs with user specified roll period and damping?

Current effects on specified wave periods?

Meaning of "encounter period" with nonzero vessel speed?

Current not equivalent to vessel speed option in simulations?

RAOs: Monotonically decreasing array required?

RAOs: Vessel speed specification treatment?

Treatment of trim and heel in simulations?

Metric to English conversions?

Differing motions for user-supplied vs computed damping?

Maximum value estimates for wave-frequency variables?

How to accomplish "Batch" runs using SeaSoft?

Zero up-cross periods for accelerations?

Clarification of "bandwidth parameter" for SeaSoft swell?

Cross-platform compatibility of binary data files (CATDAT, etc.)?

Help with importing old datafiles into recent applications.

Significance of differing alert designator darts in SeaSoft.

Semisim: Best to use regular wave height or slope for RAO generation?

Constant wave slope versus constant wave height in SeaSoft RAO estimates.

Regular wave "slope" versus "height" specification: Different output for identical input?.

Help with wave-frequency damping interpretation.

Version 5.5+ LF_SpecDat.stxt file appearance?

Version 5.5+ Node_Motn.stxt file appearance?

Zero values for all wave-frequency "Y" motion components in Node_Motn.stxt?

Reliability of net and environment-specific damping and RMS low-frequency motion values in LOWOUT?

Lateral damping levels in near-aligned conditions.

Coordinate origin for vessel fairlead coordinates when using USERRAOS.txt?

"Regular Wave Period" array versus the frequency array contained in USERRAOS.txt?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Explain "SeaSoft significant Low; maximum High algorithm"?

Metric to English conversions?

How do I set TLP tendon lengths?

Mixed vertical and conventional catenary lines?

Constant-tension riser simulation?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

How to estimate current spectral density?

Wholly new vessel & mooring system: datafile creation strategies?

Current and wind vertical area centroids for Sparsim?

Best current force model for semisubmersibles?

"Legacy" status flag warnings?

Missing multiple wave heading option for comprehensive simulations?

How to use dimensional wind and current force coefficients?

Meaning of "member dimension" for Semisim member specification?

How to use Semisim for TLP wave-frequency RAOs?

Meaning of "Utilize ONLY square law driving forces" option for semi-type vessels?

"SeaSoft Upper Bound Algorithm" and brethren; explain differences?

"Large-amplitude nonlinear model for w.f. loads"; guidelines?

"Peak Factor Multiplier" behavior with "Auxiliary External Forcing" option?

"Select alternate equilibrium" flag; produces unexpectedly large loads?

Vessel deadweight data in "Tanker Help" facility lost on program termination?

Limits to per-run wave directions for RAOs in Shipsim/Semisim/Discsim?

Advice on use of "Legacy" parameters?

Confusion over "Legacy" flags...

More "Legacy" flag confusion: The "legacy normal mode" flag...

Legacy flags in SPMsim; version 5.47 versus v 5.53...

Difference in "Swell" versus "Irregular Wave" handling and specification in comprehensive sims?

Source material for Ochi-Hubble and TMA wave spectra?

Help with importing old datafiles into recent applications.

Semisim non-agreement of two heave RAOs with identical damping.

Semisim: Best to use regular wave height or slope for RAO generation?

Constant wave slope versus constant wave height in SeaSoft RAO estimates.

Regular wave "slope" versus "height" specification: Different output for identical input?.

SNAPOUT, RANOUT peak line load discrepancy?

Definition of Surge direction in CALMsim?

CALMsim "synchronization error" messages?

Reports of "INF" for loads and motions in CALMsim?

Meaning of "Nonzero IER = 2" warning?

Persistent non-zero mean heading for turret FPSO in waves only?

Meaning of "Null Determinant" message when equilibrium finding?

Modal stiffness definition for legacy high sway-yaw mode?

SPMsm problematic single line mooring with slack-tethered surface buoy.

What does "Roughly parallel to mean offset" mean, exactly?

Single mooring line considerations.

SNAPOUT, RANOUT peak line load discrepancy?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Meaning of "Null Determinant" message when equilibrium finding?

Version 5.5+ Normal Mode Model discussion?

Smaller line loads with v 5.5+ normal mode model?

VFz and VFz+ meaning and differences in XCLDAT?

Version 5.5+ Normal Mode treatment; fails a symmetry test?

Legacy Low-Frequency correlation model flag?

Failure of XCLDAT to be produced; due to interpolation table error messages?

Stand-alone CALM buoy motions corrected for wave-frequency mooring line loads?

Semi-submersible or shipshape motions corrected for wave-frequency mooring line loads?

What does "Roughly parallel to mean offset" mean, exactly?

Mooring feedback in wave-frequency dynamics for Moorsim/Sparsim/TLPsim?

Failure of expected Sparsim/Moorsim/TLPsim output symmetry in a rotated environment.

Best wind force calibration procedure to match model test?

Current effects on specified wave periods?

How to estimate current spectral density?

Current and wind vertical area centroids for Sparsim?

"Select alternate equilibrium" flag; produces unexpectedly large loads?

Wave basin support: quartering conditions and rotated vessel & moorings?

SeaSoft equivalence of LCG, waterplane centroid, midships point?

Unreasonably large wave-frequency load variations?

Longitudinal strain waves in mooring lines; internal damping neglected?

Anchor load discrepancy between RANOUT and XCLDAT?

Failure of XCLDAT to be produced; due to interpolation table error messages?

Lazy Wave Rider interpolation table anomaly?

SPMsm problematic single line mooring with slack-tethered surface buoy.

Low-frequency envelope asymmetry...

Inconsistent fairlead location warning?

Moorsim disagreement between "snapshot" mooring loads in SNAPOUT/LOWOUT/XCLDAT?

Asymmetry reversal of +/- RMS and +/- peak amplitudes in LOWOUT?

Unusual tension-offset behavior when using LINE_STRAIN_DB.txt?

Underestimated current loads on lines in LOWOUT?

Nonsensical mean line loads in MEANOUT for neutrally buoyant lines and low pretension?

Single mooring line considerations.

SeaSoft coordinate origin for non-fore-aft-symmetric vessels?

How many interpolation layers for deepwater applications in Moorsim and SPMsim?

User forces on moorings in Moorsim?

LOWOUT reported current loads on lines and risers.

Differing MEANOUT load values depending on setting of nodal load option?

Discussion of "Hinge_Motn.stxt" output file?

Zero values for some angular variations "Hinge_Motn.stxt" output file?

"Ball Hinge" definition in Moorsim motion support files SHIPRAO.stxt, SHIPRAN.stxt?

Missing Hinge-Motion.stxt file?

Mooring stiffness in MEANOUT doesn't match stiffness in LOWOUT for "legacy" Sparsim/TLPsim runs?

How good is the Legacy "narrow-banded" response assumption for low-frequency excitations?

Calculation of snapshot vessel positions and low-frequency line loads in Moorsim

Calculation of snapshot vessel positions and low-frequency line loads in SPMsim

Clarification of "low sway-yaw mode" outputs in LOWOUT?

Missing output for angular values for the legacy "low sway-yaw mode" in LOWOUT?

Inconsistent RMS motions between LOWOUT and XCLDAT?

Version 5.5+ Normal Mode Model discussion?

Smaller line loads with v 5.5+ normal mode model?

Version 5.5+ Normal Mode treatment; fails a symmetry test?

Legacy Low-Frequency correlation model flag?

Modal stiffness definition for legacy high sway-yaw mode?

Non-recovery of legacy results when normal mode rotations in effect?

"Legacy" versus "Non-Legacy" handling of user-specified low frequency damping in SPMsim?

Execution failures in SPMsim with "Non-Legacy" normal mode processing?

Differences in "Legacy" and "Non-Legacy" SPMsim output for aligned conditions?

Change in SPMsim legacy low sway-yaw mode peak amplitudes at version 5.5x?

Normal mode periods corrected for damping?

Change in equilibrium "surge" offset sign in SPMsim?

Comparison of Moorsim low-frequency motion statistics and peaks: legacy versus non-legacy?

What does "Roughly parallel to mean offset" mean, exactly?

Changes in SPMsim "legacy" sway-yaw normal mode periods between versions 5.4 and 5.5?

More "Legacy" flag confusion: The "legacy normal mode" flag...

Legacy versus Non-Legacy normal mode periods in SPMsim?

Version 5.5+ normal mode decomposition for SPMsim; yaw reporting in LOWOUT?

Non-equivalence of "Legacy" and "Non-Legacy" low-frequency motions in aligned conditions?

Large differences in SPMsim's low-frequency yaw between "legacy" and "non-legacy" treatments?

Is TLPsim missing pitch and roll "normal mode" pages in LOWOUT.stxt?

Aligned legacy and non-legacy low-frequency RMS motion disagreement.

Moorsim: "Expanded frequency grid for cross-correlation integration"?

Reliability of net and environment-specific damping and RMS low-frequency motion values in LOWOUT?

Lateral damping levels in near-aligned conditions.

Best wind force calibration procedure to match model test?

RAOs: Vessel speed specification treatment?

User roll RAOs plus SeaSoft nonlinear damping corrections?

Reference origin for angular RAOs in USERRAOS file?

Expansion of user environmental spectrum capacity.

NAN appearances in XCLDAT when going from built-in RAOS to user-supplied RAOs?

Angular RAOs in Shipsim/Semisim/Discsim versus WAMIT...

"Dimensionless" RAOs for use in USERRAOS.txt...

Use of SeaSoft damping estimates in conjunction with USERRAOS.txt?

Current corrections for user-supplied wave drift coefficients (DRFTCOFS.txt)?

Yaw Moment arm used for wind and current forces?

"Spectral value of force at resonance" and "Spectral value of Z moment at yaw resonance"?

User forces on moorings in Moorsim?

Coordinate origin for vessel fairlead coordinates when using USERRAOS.txt?

"Regular Wave Period" array versus the frequency array contained in USERRAOS.txt?

Wave drift force spectrum: Defined frequency range?

KCAT, KCATO, SIGCQ error warnings?

SPMsim Low-Frequency surge direction definition?

LOWOUT discrepancy in line load snapshot and maximum storm line load?

SNAPOUT, RANOUT peak line load discrepancy?

Extreme vessel motion estimates?

Best wind force calibration procedure to match model test?

RMS spectral load estimates with azimuthal wave spreading?

Zero (current, wind, wave) magnitudes vs turning (current, wind, wave) off?

Loss of nonlinear mooring response with user-specified periods and damping

Effect of current speed on wave-drift force magnitudes?

Problems with motion RAOs with nonzero vessel speed?

Meaning of "(+)" in "Low-frequency Contribution (+)"?

Fairlead vs Anchor maximums in RANOUT?

RANOUT's "one page per line" versus tabular summary output differences?

Explain "SeaSoft significant Low; maximum High algorithm"?

Reports of "INF" for loads and motions in CALMsim?

How is the Maximum Loads Turnaround Point derived?

Maximum value estimates for variables containing both wave-frequency and low-frequency components?

Units of current and wind spectral density?

How to estimate current spectral density?

How good is the Legacy "narrow-banded" response assumption for low-frequency excitations?

Calculation of snapshot vessel positions and low-frequency line loads in Moorsim

Calculation of snapshot vessel positions and low-frequency line loads in SPMsim

Current drag on bottom-lying lines?

Wholly new vessel & mooring system: datafile creation strategies?

Persistent non-zero mean heading for turret FPSO in waves only?

"Number of lines for dynamic evaluation"; unexpected behavior?

Tangential drag on moorings and risers?

How to eliminate wave frequency line damping of low-frequency motions?

Current and wind vertical area centroids for Sparsim?

Best current force model for semisubmersibles?

Azimuthal asymmetry of wind and current forces for spars?

Missing pulldown estimates for ships and semis in SPMsim, Moorsim?

"Legacy" status flag warnings?

Missing multiple wave heading option for comprehensive simulations?

How to use dimensional wind and current force coefficients?

"Interpolation layer" optimization?

"SeaSoft Upper Bound Algorithm" and brethren; explain differences?

How to simulate a nonzero moment on a symmetric vessel (buoy or spar)?

Inconsistent RMS motions between LOWOUT and XCLDAT?

"Large-amplitude nonlinear model for w.f. loads"; guidelines?

Vertical area centroids and pitch/roll moments; relationship?

"Peak Factor Multiplier" behavior with "Auxiliary External Forcing" option?

Large wave-frequency anchor-end tensions?

"Select alternate equilibrium" flag; produces unexpectedly large loads?

Differing peak amplitude factors for variable current, wind and waves?

Guidelines for use of line load reporting options (Upper Bound, Lower Bound and brethren)?

Trim and heel warning message purpose and meaning?

Vessel deadweight data in "Tanker Help" facility lost on program termination?

Meaning of "phase" as applied to net vessel loads in SNAPOUT?

How to accomplish "Batch" runs using SeaSoft?

Best procedure for doing "Batch" runs?

Water depth/draft parameter warning?

Current loads on lines anomalously large?

Treatment of peak factors for independent swell and waves?

User roll RAOs plus SeaSoft nonlinear damping corrections?

Meaning of "Null Determinant" message when equilibrium finding?

Azimuthally symmetric system fails to exhibit azimuthally symmetric output?

Wave basin support: quartering conditions and rotated vessel & moorings?

Questionable peak excursion estimates for surge & sway in crossed conditions?

Current loads on bottom-resident line segments?

S.L.O.R. handling of risers in Moorsim?

LOWOUT and RANOUT disagreement on maximum quasi-static line tensions?

Moorsim "line on bottom" shows negative values?

Reference origin for angular RAOs in USERRAOS file?

Wind waves + swell: meaning of "bandwidth", etc., in XCLDAT output?

Wildly different interpolation table for similar lines?

First interpolation table row; runtime warning due to buoyant line segments?

Unreasonably large wave-frequency load variations?

Longitudinal strain waves in mooring lines; internal damping neglected?

Anchor load discrepancy between RANOUT and XCLDAT?

Failure of XCLDAT to be produced; due to interpolation table error messages?

Changes in the interpolation table load granularity in version 5.3+?

Cross-platform compatibility of binary data files (CATDAT, etc.)?

Max/min net vessel load discrepancy; SNAPOUT versus XCLDAT?

Modal stiffness definition for legacy high sway-yaw mode?

RelBow, RelMoon and RelMoorCentr in XCLDAT; what are they?

Causes of NAN occurrences in XCLDAT?

Is there a glossary of the XCLDAT variables?

XCLDAT "WF_Zero_Up" definition?

Where can I find more XCLDAT documentation & discussion?

Discrepancy in low-frequency and wave-frequency RMS loads; RANOUT versus XCLDAT.

Non-recovery of legacy results when normal mode rotations in effect?

Semi-submersible or shipshape motions corrected for wave-frequency mooring line loads?

Forward speed versus current in Slowsim?

Disagreement between "Global system" and "Vessel system" loads in MEANOUT?

Advice on use of "Legacy" parameters?

XCLDAT "relative motion" Wave-Frequency max/min/mean values in SPMsim and Moorsim?

User-specified roll damping and wave drag connection?

Lazy Wave Rider interpolation table anomaly?

Inconsistency in XCLDAT "Gy" wave-frequency RMS and that reported by SHIPRAN.stxt?

"Legacy" versus "Non-Legacy" handling of user-specified low frequency damping in SPMsim?

Normal mode periods corrected for damping?

Crossed seas and low-frequency response: wave drift force estimation...

Low-frequency envelope asymmetry...

Change in equilibrium "surge" offset sign in SPMsim?

What does the "(right-hand rule)" notification in LOWOUT refer to?

Coordinate system overload in LOWOUT?

Asymmetry reversal of +/- RMS and +/- peak amplitudes in LOWOUT?

Unusual tension-offset behavior when using LINE_STRAIN_DB.txt?

Changes to low-frequency wave reflection and absorption damping following version 5.5?

Confusion over "Legacy" flags...

More "Legacy" flag confusion: The "legacy normal mode" flag...

Expansion of user environmental spectrum capacity.

User-specified versus simulation-chosen dynamic heading control spring constant in SPMsim...

Erroneous (a) current spectral density, or (b) current low-frequency motions in LOWOUT?

Difference in "Swell" versus "Irregular Wave" handling and specification in comprehensive sims?

NAN occurrences (what is NAN, anyhow?) and other bizarre XCLDAT behavior?

NAN appearances in XCLDAT when going from built-in RAOS to user-supplied RAOs?

Differences in MEANOUT and LOWOUT net loads?

Underestimated current loads on lines in LOWOUT?

Nonsensical mean line loads in MEANOUT for neutrally buoyant lines and low pretension?

"Dimensionless" RAOs for use in USERRAOS.txt...

Single mooring line considerations.

Non-equivalence of "Legacy" and "Non-Legacy" low-frequency motions in aligned conditions?

Current corrections for user-supplied wave drift coefficients (DRFTCOFS.txt)?

Failure of expected Sparsim/Moorsim/TLPsim output symmetry in a rotated environment.

Sign reversal in wave drag (aka absorption) coefficients in Slowsim/Moorsim?

Current forces on semisubmersibles in Moorsim?

Yaw Moment arm used for wind and current forces?

Aligned legacy and non-legacy low-frequency RMS motion disagreement.

How many interpolation layers for deepwater applications in Moorsim and SPMsim?

Moorsim: "Expanded frequency grid for cross-correlation integration"?

"Spectral value of force at resonance" and "Spectral value of Z moment at yaw resonance"?

User forces on moorings in Moorsim?

Version 5.5+ LF_SpecDat.stxt file appearance?

Version 5.5+ Node_Motn.stxt file appearance?

Node_Motn.stxt wave-frequency fairlead motion; disagreement with SHIPRAN.stxt?

Zero values for all wave-frequency "Y" motion components in Node_Motn.stxt?

Reliability of net and environment-specific damping and RMS low-frequency motion values in LOWOUT?

Equilibrium failures in Moorsim

LOWOUT reported current loads on lines and risers.

Lateral damping levels in near-aligned conditions.

Differences in SEMISUM between Sparsim and Semisim?

Vessel motions arising from combined independent wave trains.

Differing MEANOUT load values depending on setting of nodal load option?

EigenVector/EigenMode error messages

Coordinate origin for vessel fairlead coordinates when using USERRAOS.txt?

"Regular Wave Period" array versus the frequency array contained in USERRAOS.txt?

Discussion of "Hinge_Motn.stxt" output file?

Zero values for some angular variations "Hinge_Motn.stxt" output file?

"Ball Hinge" definition in Moorsim motion support files SHIPRAO.stxt, SHIPRAN.stxt?

Missing Hinge-Motion.stxt file?

SPMsim and Moorsim with steady environmental forcing fails to terminate normally.