Orcina news

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!

Important: Email Account Breach

On the 7th November 2024 a staff member’s email account was compromised and unfortunately this has resulted in phishing emails being sent to some of our customers. We were aware of the breach within minutes of it occurring and were able to quickly secure the account to prevent further malicious actions. We have investigated activity on this account and are sure this was limited to the online email account and no more.

The email sent had the subject line Emma Johnston shared “Orcina Ltd Project Report” with you, and the email contained an attachment. In many cases this will have been quarantined by your email system but if you see this email in your inbox then please delete it, do not click on any links within the email or attempt to open the attachment.

We apologize for any inconvenience and confusion this may have caused. It is embarrassing for us that this has occurred as we take security very seriously. We are consequently reviewing our security configuration.

OrcaFlex 11.4d released

We have just released a minor upgrade to OrcaFlex, version 11.4d. Version 11.4d 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 11.4d.

To upgrade to OrcaFlex 11.4d 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.

New example demonstrating the OrcaFlex interface to SHEAR7

A new example, A06 SHEAR7 interface, is now available on our website.

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.

 

An OrcaFlex model of a single line hanging in a catenary configuration with SHEAR7 logo.

New floating photovoltaic array example

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 array with 64 rectangular rafts in the array and 12 buoys in the mooring system.
OrcaFlex model of a floating photovoltaic (FPV) array.

IEA 22 MW RWT validation study

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 megawatt reference wind turbine
OrcaFlex model of the IEA 22 MW reference wind turbine
Comparison of the aerodynamic and operational steady-state response of the 22 megawatt rotor
Comparison of the aerodynamic and operational steady-state response of the 22 MW rotor
Comparison of the blade and tower response to turbulent wind
Comparison of the blade and tower response to turbulent wind

OrcaFlex 11.4c released

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.

OrcaFlex 11.4b released

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.

New diffraction example

A new example is now available on our website: L03 Semi-sub multibody analysis. This example focusses on a semi-sub platform that closely resembles the OC4 platform, as modelled in example L02.

In the L02 example, we assume the platform is a single rigid body. In the L03 example, we are interested in the loads acting through the connecting members. Consequently, we have divided the platform into four distinct floating bodies and used OrcaWave to run a multibody diffraction analysis. In OrcaFlex, the four vessel objects are connected via line objects with structural properties that represent the cross bracings and pontoons. Further details can be found in the accompanying PDF description document.

Please note that example L03 takes advantage of recent developments to improve the workflow when defining external stiffness for multibody analyses. Therefore, this example is intended for use with OrcaWave and OrcaFlex version 11.4 onward.

In version 11.4 we also developed OrcaWave and OrcaFlex to be capable of undertaking multibody analyses for objects consisting of multiple sectional bodies. This new feature is not considered as part of this example, although we hope to develop an example that will demonstrate this feature in the future.

We hope that you will find this latest example helpful and informative.

L03 Semi-sub

OrcaFlex 11.4 released

We are very pleased to announce the release of OrcaFlex version 11.4. The software was finalised and built on 22nd November. All clients with up-to-date MUS contracts will receive, in the week starting 27th November, an e-mail with instructions on how to download and install the new version.

Version 11.4 introduces much new functionality, including:

OrcaFlex

OrcaWave

These are the most significant developments, in our opinion. As always there are more enhancements that are not listed here. All new features are fully documented in the what’s new topics:

Continue reading “OrcaFlex 11.4 released”