Issue running without yaw

[lucamholden-arch]

Hi there, ive been able to setup and run simulations for a while now but have come across i case i can't seem to fix. Initially i was testing the differences between polar and curl and found out i needed to add yaw to see the kidney shape on curl. Now removing that yaw for other simulation is causing me issues. When i set it to 0 i get this error and cant seem to fix it so am left just running with yaw? thanks for your continued help

[jjonkman]

Dear @lucamholden-arch,

You mention setting yaw to zero, but the first warning is about large skew (chi) and the other warnings and eventual error suggest that your model is unstable or undergoing an unrealistically large transient.

Can you clarify how you are setting yaw to zero? Do you have the YawDOF enabled in ElastoDyn? If so, are you setting both NacYaw in ElastoDyn and YawNeut in ServoDyn to the same value? For a related issue, see: #2574.

Best regards,

[lucamholden-arch]

Hi @jjonkman so thanks for that I had missed the servoDyn value :)
I am now running a rather basic full simulation of 3 floating turbines behind each other, It runs perfectly fine with 1 wind turbine for the full time but when i add 2 and 3 i get this error below that is my fsts start. I am confused by this error as ive had it when using turbsim before but this time it is under a constant wind flow which has lost me, thanks for your help

------- FAST.Farm for OpenFAST INPUT FILE -------------------------------------------------
FAST.Farm input file, using two turbines separated by 3D downstream and an offset of 30m, with a turbulent inflow given by one turbsim box
--- SIMULATION CONTROL ---
False Echo - Echo input data to .ech? (flag)
FATAL AbortLevel - Error level when simulation should abort (string) {"WARNING", "SEVERE", "FATAL"}
1400.0 TMax - Total run time (s) [>=0.0]
2 Mod_AmbWind - Ambient wind model (-) (switch) {1: high-fidelity precursor in VTK format, 2: one InflowWind module, 3: multiple instances of InflowWind module}
2 Mod_WaveField - Wave field handling (-) (switch) {1: use individual HydroDyn inputs without adjustment, 2: adjust wave phases based on turbine offsets from farm origin}
0 Mod_SharedMooring - Shared mooring system model (switch) {0: None, 3=MoorDyn}}
--- SHARED MOORING SYSTEM --- [used only for Mod_SharedMoor>0]
"" SharedMoorFile - Name of file containing shared mooring system input parameters (quoted string) [used only when Mod_SharedMooring > 0]
0.04 DT_Mooring - Time step for farm-level mooring coupling with each turbine (s) [used only when Mod_SharedMooring > 0]
true WrMooringVis - Write shared mooring visualization, at the global FAST.Farm time step (-) [only used for Mod_SharedMooring=3]
--- AMBIENT WIND: PRECURSOR IN VTK FORMAT --- [used only for Mod_AmbWind=1]
3.0 DT_Low-VTK - Time step for low -resolution wind data input files; will be used as the global FAST.Farm time step (s) [>0.0]
0.1 DT_High-VTK - Time step for high-resolution wind data input files (s) [>0.0]
"unused" WindFilePath - Path name to VTK wind data files from precursor (string)
False ChkWndFiles - Check all the ambient wind files for data consistency? (flag)
--- AMBIENT WIND: INFLOWWIND MODULE --- [used only for Mod_AmbWind=2 or 3]
0.4 DT_Low - Time step for low -resolution wind data interpolation; will be used as the global FAST.Farm time step (s) [>0.0]
0.1 DT_High - Time step for high-resolution wind data interpolation (s) [>0.0]
281 NX_Low - Number of low -resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
121 NY_Low - Number of low -resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
30 NZ_Low - Number of low -resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
-600.0 X0_Low - Origin of low -resolution spatial nodes in X direction for wind data interpolation (m)
-600.0 Y0_Low - Origin of low -resolution spatial nodes in Y direction for wind data interpolation (m)
5.0 Z0_Low - Origin of low -resolution spatial nodes in Z direction for wind data interpolation (m)
10.0 dX_Low - Spacing of low -resolution spatial nodes in X direction for wind data interpolation (m) [>0.0]
10.0 dY_Low - Spacing of low -resolution spatial nodes in Y direction for wind data interpolation (m) [>0.0]
10.0 dZ_Low - Spacing of low -resolution spatial nodes in Z direction for wind data interpolation (m) [>0.0]
16 NX_High - Number of high-resolution spatial nodes in X direction for wind data interpolation (-) [>=2]
16 NY_High - Number of high-resolution spatial nodes in Y direction for wind data interpolation (-) [>=2]
16 NZ_High - Number of high-resolution spatial nodes in Z direction for wind data interpolation (-) [>=2]
"IW.dat" InflowFile - Name of file containing InflowWind module input parameters (quoted string)
--- WIND TURBINES ---
3 NumTurbines - Number of wind turbines (-) [>=1] [last 6 columns below used only for Mod_AmbWind=2 or 3]
WT_X WT_Y WT_Z WT_FASTInFile X0_High Y0_High Z0_High dX_High dY_High dZ_High
(m) (m) (m) (string) (m) (m) (m) (m) (m) (m)
0.0 0.0 0.0 "FFTest_WT1.fst" -70.0 -80.0 5.0 10.0 10.0 10.0
756.00 0.0 0.0 "FFTest_WT2.fst" 686.0 -80.0 5.0 10.0 10.0 10.0
1512 0.0 0.0 "FFTest_WT3.fst" 1442 -80.0 5.0 10.0 10.0 10.0

[jjonkman]

Dear @lucamholden-arch,

It appears that an aerodynamic analysis node of T3 falls outside of the high-resolution. I see your high-resolution domain extends from 5 to 155 m in steps of 10 m, but the error mentions trying to access a point 0.05 m higher than that, perhaps from turbine motion (displacement/deflection).

Best regards,