I think if you remove the key word “ABSTRACT” from the specification of the three interface statements in OrcaFlexInterface.f90 (reported on lines 114, 127, and 145, the first 3 errors in your attachment), that will solve your issue.
This was fixed in OpenFAST a while ago. Older Fortran compilers allowed this syntax (with the ABSTRACT key word), though it is technically not correct.
Dear Bonnie,
Thanks for the input. Based on the suggestion, I have removed the word ABSTRACT from line 106. The errors changed into somewhat different this time. Any guidance would be helpful.
P.S. Facing an http error to attach text document.
“Severity Code Description Project File Line Suppression State
Error fatal error LNK1169: one or more multiply defined symbols found …..\bin\FAST_dev_Debug_Win32.exe
Error error LNK2005: _powf already defined in libmmt.lib(powf_iface_c99.obj) mkl_core.lib(dlarfgn.obj)”
Thanks and regards
Abhinay Goga
The linking error you show is typically caused by a mismatch between libraries used to link the final executable. I don’t recall the details of FAST8 builds, but make sure you are using consistent libraries and compile settings in all the files and projects. The first place I would check is under “properties”, “Configuration properties->Fortran->Libraries->Runtime library”. Those settings should be the same for all projects. Another thing to check is that the settings under “Configuration properties->Fortran->Floating point” are the same in all projects in the solution.
With one version of the compiler, I recall the OrcaFlex interface files couldn’t be optimized, so that might be causing trouble, too. (right-click on the OrcaFlexInterface.F90 file, select “properties” and then set “Configuration Properties->Fortran->Optimization->Optimization” to “Disable (/Od)”). Though, in debug mode it’s probably already turned off optimizations.
Dear Bonnie and Matt,
Thanks for guidance. With configuring the properties to release,the recompilation is successful.
The Fairlead tension for line 1 after 50 sec reaches zero, yet there are are no significant rise in the loads for remaining lines. And in the mooring file, I have designed 9 lines (with 2 connections for each). Anchor 7 tension for line 1 is not resulted as zero. Could you please make a comment about this behavior?
Thanks and regards
Abhinay Goga
Dear Abhinay,
I’m glad that you’ve now successfully compiled your updated source code.
I’m not sure what type of floater this is (a semisubmersible?), and perhaps Matt can comment further, but assuming the mooring lines are centenaries, I would imagine the mean tensions in the remaining lines after the loss of line 1 would go down because the tension from line 1 is no longer pulling on them. I would suggest that you start by running simple tests (e.g. no wind and still water) to ensure that platform response is what you expect after the line loss.
Best regards,
Dear Jason and Matt,
Thanks. The floater is OlavOlsen Semi-submersible star floater. My aim is to validate fiber ropes instead of conventional catenary chains. My connections of lines look like the following:
“Line LineType UnstrLen NumSegs NodeAnch NodeFair Flags/Outputs
(-) (-) (m) (-) (-) (-) (-)
1 chain 60 6 4 1 -
2 chain 60 6 5 2 -
3 chain 60 6 6 3 -
4 fiber 80 8 7 4 “ptsd”
5 fiber 80 8 8 5 “ptsd”
6 fiber 80 8 9 6 “ptsd”
7 chain 60 6 10 7 -
8 chain 60 6 11 8 -
9 chain 60 6 12 9 -”
Based on your suggestion, I ran complete static situation without any initial offsets. The performance of the floater seems reasonable with increase in surge and heave. However, the anchor tensions seems not in order. Can anyone please clarify, why there is such behavior on anchors?
Thanks and regards
Abhinay Goga
Dear Abnhinay,
The results you’re seeing are as I’d expect. My understanding was you were only concerned with simulating the results of a line failure on the floater itself. You’ll see the code I helped you with simply zeroes the forces of the failed line on the platform; it does not do anything to physically free the line from the floater. So the line still acts attached to the platform and has the corresponding tensions. Only the floater does not feel the line anymore.
Hopefully this approach meets your needs. If you actually wanted to model the effect of the simulated failure within the mooring system as well, it would be considerably more complicated. You would need to add additional states to the system for the freed line end, which would convert from “vessel” to “connect” type. These capabilities will be developed eventually, but they aren’t quick to do.
Best,
Matt
Dear Matt,
Understood that the source code you helped with creates a Pseudo event of transient line loss. Thanks for all the guidance and support. For my thesis, the implemented model is suffice. Looking forward to future improvements on the glue codes.
Kind regards
Abhinay Goga
