Thanks for the information. In fact, I did tried several things like a) using TMax and DT values similar to the pull373 branch input parameters used in 5MW land mode shapes case. With TMax=5600 and Dt=0.001 the simulation runtime is long. Except for the results of the 1st tower FA, all other values do not match with previous results (please see the attachment for the figure). Furthermore, simulations for some rotor speeds have aborted (see below for the output from openfast with the fatal error). I tried to rerun the aborted cases to double-check if there is any problem. I think the simulation aborts at the last timestep when the linearization has started as the steady state solution is not found. b) I have seen here in the forum that researchers used previous versions of fast with larger timestep like 0.0125s and smaller simulation time of 240s to get the right results. However, if I use DT>0.002 I see convergence errors and simulation aborts without reaching the linearization step c) I have also tried using the dev branch to see if I get any better results with simulation time like 1000s and Dt = 0.001 but the simulation aborted at after ~620s with a fatal error. In all these cases I was using CompElast and CompServo flags ON. Why is this difference between openfast and previous fast versions? Could you please suggest any reasonable values that can work for generating the Campbell diagram with the OpenFast dev branch?
2. Yes, I was initially using only the Matlab script to automatically generate the Campbell diagram without copying data from MBC3 output. But since I was not seeing the correct results, I started using the excel sheet manually copying the MBC3 output to cross-check.
3. Regarding the NLinTimes and Lintimes. In all cases except 0 rpm when NLinTimes=1, Is it right the runcampbell script does some averaging to produce the Campbell diagram?
- Compiler: GCC version 7.1.0
- Architecture: 64 bit
- Precision: double
- Date: May 19 2020
- Time: 10:03:26
- Date: 06/24/2020
- Time: 09:11:15+0530
OpenFAST input file heading:
FAST Certification Test #18: NREL 5.0 MW Baseline Wind Turbine (Onshore)
AllBldNd section of ElastoDyn input file not found or improperly formatted. Therefore assuming no
nodal outputs. --> Premature EOF for file "./NRELOffshrBsline5MW_Onshore_ElastoDyn-4.dat"
occurred while trying to read BldNd_BladesOut.
FAST_InitializeAll:ED_Init:ED_SetParameters:AllBldNdOuts_ValidateInputData: Number of blades to
output data at all bladed nodes (BldNd_BladesOut) must be between 0 and 3.
Time: 0 of 5600 seconds.
Time: 3805 of 5600 seconds. Estimated final completion at 09:51:58.
Time: 5600 of 5600 seconds. Estimated final completion at 09:52:01.
Unable to find steady-state solution.
FAST encountered an error at simulation time 5600 of 5600 seconds.
Simulation error level: FATAL ERROR