Here you will find the latest news on the development of OrcaFlex. Alongside our LinkedIn page, it is a valuable source of information about what we are up to!
The example illustrates how to access the OrcaFlex interface to SHEAR7, using the steel catenary riser system considered in the A05 Catenary with spar example.
SHEAR7 is a third-party program, distributed by AMOG, which performs frequency domain VIV analysis for the purpose of estimating fatigue and/or drag amplification due to VIV. A separate licence is required to run SHEAR7 through the interface. However, the example results can be viewed without a SHEAR7 licence.
The accompanying PDF document provides detail on how to access the interface, what input data are required and how to access the VIV results. However, the example does not address how to choose appropriate values for the SHEAR7 data inputs, as these relate to SHEAR7 itself, rather than the OrcaFlex interface.
We hope that the example provides a useful guide to the SHEAR7 interface, allowing it to be used effectively.
A new example, K06 FPV array, is now available on our website. This example demonstrates one method of modelling a floating photovoltaic (FPV) array system in OrcaFlex and can be found in the K Renewables section of the OrcaFlex examples webpage.
The array is made up multiple modular rafts which are connected using indirect constraints with double-sided connections. The array model was built by duplicating a template model which represents a single raft module. The model building process was automated using the OrcaFlex programming interface (OrcFxAPI) and this is demonstrated in the Python script supplied alongside this example.
The accompanying PDF document goes into further detail on the model building process, setting data and interpreting results. It also includes a discussion on indeterminate systems and how they can sometimes arise.
We hope that this example is informative and can provide some useful insights into both new and existing OrcaFlex features that can help model floating array systems.
OrcaFlex model of a floating photovoltaic (FPV) array.
We have recently put together a validation study which compares the aeroelastic response of the IEA 22 MW reference wind turbine (RWT) calculated by OrcaFlex, versus OpenFAST (running BeamDyn).
A report summarising a full comparison of results can be downloaded from the validation page of the Orcina website. The study considers the structural dynamics of the turbine blade oscillating freely under gravity and the aeroelastic response of the rotor-nacelle assembly (RNA) & tower to steady, stepped, skewed & turbulent wind.
Included with the report is the OrcaFlex model we have used to support the validation study. The model includes the rotor, nacelle and tower only i.e. no fixed / floating foundation has been considered as part of this study. The data used as input to this model have been gathered from version 1.0.1 of the the windIO dataset, made available through the IEA-22-280-RWT GitHub repository. The windIO ontology contains the majority of data required to specify an OrcaFlex turbine model. Any absent data have been sourced from the available OpenFAST and HAWC2 datasets. Further details about this can be found in Section 2.1 of the validation report.
Also included with the model is version 2.9.0 of NREL’s Reference Open Source Controller (ROSCO), complete with the necessary input files distributed as part of the ‘IEA-22-280-RWT-Monopile’ dataset.
Overall, we have found the results to be in very close agreement, supporting both the validity of the OrcaFlex RWT model and consistency across the two aeroelastic codes. Included below are some select results from the validation report.
We hope this resource will be helpful to anyone modelling wind turbines in OrcaFlex. We always welcome any questions or feedback, so please do contact us for any further enquiries.
OrcaFlex model of the IEA 22 MW reference wind turbineComparison of the aerodynamic and operational steady-state response of the 22 MW rotorComparison of the blade and tower response to turbulent wind
We have just released a minor upgrade to OrcaFlex, version 11.4c. Version 11.4c fixes a number of bugs. Full details of the changes are described in the documentation:
We recommend that all users of 11.4 upgrade to 11.4c.
To upgrade to OrcaFlex 11.4c from any previous version, download the install program from your company’s Orcina software download page. A link to this page was sent to your software administration contact when we released 11.4a. If you do not have access to this page, please contact us.
We have just released a minor upgrade to OrcaFlex, version 11.4b. Version 11.4b introduces some minor new functionality and fixes a number of bugs. Full details of the changes are described in the documentation:
We recommend that all users of 11.4 upgrade to 11.4b.
To upgrade to OrcaFlex 11.4b from any previous version, download the install program from your company’s Orcina software download page. A link to this page was sent to your software administration contact when we released 11.4a. If you do not have access to this page, please contact us.
