Case Study

Wind turbine tilting mast: independent structural verification before manufacture

Structural verification of a client-designed 18m tilting mast, including finite element analysis, manual checks and formal substantiation report

Sprint

Renewable energy

Structural substantiation

FEA + manual calculations

Example FEA stress plot from the structural report

Situation

A wind turbine manufacturer had developed an 18m tilting mast for one of their turbines and needed independent structural verification prior to manufacture. The brief was to assess the mast structure and lowering arrangement under operational and maintenance load cases, using finite element analysis, supporting manual checks and a formal substantiation report.

The real problem

Although the brief itself was straightforward, the work was not just a simple stress check on an upright mast. The structure had to be verified across multiple operating and maintenance positions, including its hydraulic lowering mechanism, and considering modal behaviour, fatigue checks and local design details alongside the main global strength and deflection checks.

Constraints

Verification-only remit: the remit was to verify and substantiate a client-designed mast, not redesign any failing areas.
Multiple analysis scenarios: verification had to cover raised, lowered and critical-angle positions during maintenance.
Multiple assessment criteria: strength, deflection, reactions, utilisation / factor of safety, modal behaviour and fatigue all had to be assessed.
Hybrid FE modelling needed: the structure called for a mixed shell/solid model, multiple materials and realistic modelling of mass distribution.
Out-of-scope turbine geometry: the turbine was outside the main FE scope, but still needed representative mass and geometry for correct loading and modal results.

Client:

Wind turbine manufacturer

Role:

Mechanical engineering consultant

Period:

2024

Scope:

FEA-led structural verification +
Structural analysis report

Acceptance basis:

Client detail design +
Code-aligned substantiation +
Client / third-party approval

Key moves

Built a clean reference model and FE model suite

Produced a 3D reference model from client drawings and 3D data for checking, measurement, illustrations and FE model generation.
Built the analysis models needed for the different mast positions and verification types, including strength, frequency and fatigue.

Defined the load regime and ran the verification

Derived the loading basis and applied it across the model suite for the relevant operational and maintenance conditions.
Solved the models, then collated and reviewed the results to identify governing behaviours, critical details and any initial failures.

Fed back issues and re-checked the revised design

Reported some first-pass failures to the client and advised on which design changes were likely to be worth pursuing.
Updated the FE models to reflect the revised design and re-ran the analyses, with the second pass achieving acceptable results.

Documented the verification in a formal report

Collated the final analysis results into a structural report covering the modelling approach, load cases, results and conclusions.
Completed the supporting manual checks needed to substantiate the FE findings and finalise the verification package.

Selected snapshots

Cropped FEA model views, showing mast shell geometry, mesh quality checks and example stress results.

Selected extracts from the structural substantiation report.

Fabricated mast sections and connection details during manufacture, before and after finishing.

Outcome

A compliant design basis was demonstrated following a second verification pass, and a formal structural substantiation report was issued to the client for review and approval. The final package documented the analysis models, load cases, key results and supporting manual checks in a form that could be used as a proper engineering basis rather than just a set of raw outputs.

What this enabled

This gave the client the evidence needed to support end-customer approval discussions and move forward with procurement and fabrication of the mast. In practical terms, it turned the work from an internal design question into something they could review, approve and act on with more confidence.

Business perspective

The client engaged constructively with the findings, revised the design in response to first-pass failures, and ultimately relied on the work to support design review and move forward with procurement and manufacture on a better-informed basis.

Based on archived project emails

Contact

If you need to solve a problem and you’d like to explore whether I can help, drop me an email:

What to include

To help me give you a useful reply, please mention…

What you’re building or dealing with (one or two sentences)
What’s going wrong, what decision you’re trying to make, or where the brief still feels unclear
Key constraints (budget, timescale, materials, interfaces, standards)
What information you already have (CAD, drawings, photos, etc)
Desired outcome (e.g. clearer brief, options report, CAD, calcs, FEA)
Any deadlines and why they exist (so I can reality-check them)

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What happens next?

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If it's a fit, I will:

Tell you whether and how I can help
Give you some options for how we could move forward
Ask for the minimum info needed to clarify and scope it

If it's not a fit, I will:

Say so, and tell you why
Suggest an alternative route, if appropriate

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