Instrumentation & measurement
Experimental aerothermal methods
A coherent thread through open-hardware pneumatic probes, multi-facility calibration, and rigorous uncertainty propagation, the measurement layer behind turbomachinery research at the Oxford Thermofluids Institute and peer-reviewed work on publications.
Not sure where to start? 4 places to go
Start with your question
Why visitors arrive: You work with pneumatic probes, turbine rigs, or aerothermal instrumentation and need methods guidance.
Your question: How are multi-hole probes calibrated, transferred between facilities, and uncertainty-budgeted?
You may also be asking
- What is the difference between 3-hole and 5-hole probes?
- Where is the Oxford open-hardware probe work?
- Is there an interactive uncertainty tool?
Where to go next
- Pneumatic probes overview: Choose probe type and workflow
- Uncertainty fundamentals: Bias, precision, propagation vocabulary
- 3-hole probe uncertainty note: Full derivation
- Experimental measurement article: Campaign-level traceability
- Scope: Pneumatic probing, pressure-transducer metrology, calibration transfer between wind tunnels, and bias-precision analysis
- Author: Lucas Rey, Oxford Thermofluids Institute · ORCID · Oxford probe manuscript
- Methods layer: Aerothermal engineering methods: cross-cutting experiment and CFD validation workflows
- Live resources: pneumatic probes overview, 3-hole probe uncertainty note, uncertainty fundamentals, experimental measurement article, 5-hole probe cross-calibration project, Oxford probe manuscript (in preparation)
- Planned: Interactive probe-uncertainty module on calculators; 5-hole Monte Carlo suite (see notes hub roadmap)
- Foundations: Dimensional analysis module and Reynolds-number scaling for probe and similarity work
Why measurement discipline matters
High-speed aerothermal experiments fail quietly when instrumentation error is treated as an afterthought. A biased pressure tap, an uncorrected yaw calibration, or a facility-specific polynomial fit can shift inferred loss coefficients and cooling effectiveness by margins that dominate the physics under study, as seen when merging multi-facility 5-hole probe datasets and inferring loss on ECAT rainbow vane sets for the HPT deterioration programme.
On this site that posture is documented in the Oxford open-hardware probe manuscript (in preparation), the live 3-hole probe uncertainty note, and ECAT campaign logs on the HPT project, measurement as part of the model, not an afterthought.
Pneumatic probe workflow
The following sequence is common across Oxford turbine campaigns and open-hardware probe benchmarking, details vary by facility, but the documentation structure stays the same.
- Angular calibration: sweep a probe through a known uniform flow; fit yaw coefficients and pressure-recovery polynomials
- Coefficient reduction: non-dimensional groups linking port pressures to flow angle, total pressure, and static pressure
- Uncertainty budget: separate bias (transducer, alignment, polynomial fit) from precision (repeatability, tunnel unsteadiness)
- Facility transfer: compare calibration accuracy across tunnels before merging datasets (see 5-hole probe project)
- Publication & tools: formalise derivations in notes; implement correlations in calculators when stable
Resources on this site
Pneumatic probes overview
Orientation to 3-hole, 5-hole, and 7-hole configurations, when each fits, calibration and facility-transfer workflow, and pointers to uncertainty derivations.
Measurement uncertainty fundamentals
Foundational vocabulary for bias, precision, and propagation, the layer beneath instrument-specific derivations.
3-hole probe uncertainty analysis
Full derivation of bias and precision propagation for three-hole pneumatic probes, calibration coefficients, partial derivatives, and Reynolds-number sensitivity. Suitable as a methods reference alongside experimental campaigns.
Multi-facility 5-hole probe cross-calibration
Open-hardware probe benchmarking across European wind tunnels, applies the uncertainty framework in a multi-facility context and informs the Oxford probe manuscript in preparation.
Experimental aerothermal measurement
Long-form essay on traceability, similarity, and facility transfer, the narrative layer above short notes and below peer-reviewed papers.
CFD-experiment validation
Closing the loop between RANS campaigns and transient aerothermal data, observables, boundary conditions, and uncertainty, tied to the HPT deterioration programme.
Related platform content
- Technical notes hub: knowledge clusters and methods roadmap
- Turbomachinery deterioration: flagship HPT research programme using these methods
- HPT transient thermography: ECAT data-reduction note
- Fluid mechanics curriculum: Pi groups and similarity foundations for experimental design
- Aerothermal engineering methods: cross-cutting methods cluster
- Publications: instrumentation research theme
- Engineering calculators: thermophysical utilities and planned probe tools
- CFD-experiment validation: simulation pairing workflow
- Engineering hub: full platform index
Part of
This page sits within the broader knowledge structure on lucasrey.com:
- Engineering - Central knowledge platform - tools, curriculum, notes, and research assets.
- Research - Peer-reviewed and technical publications in aerothermal and fluid engineering.
Connected work
Related content from the same research and engineering work:
- Technical notes
- Pneumatic probes overview
- 3-hole probe uncertainty note
- Uncertainty fundamentals
- Instrumentation theme - Referenced from Viscous flow - problems
- Instrumentation theme - Referenced from Ventures
- Instrumentation theme - Referenced from Articles
Part of Engineering
This page is part of the engineering knowledge platform on lucasrey.com.
- Engineering hub - Full knowledge platform index
- Turbomachinery deterioration - Rolls-Royce HPT leading-edge holing - aerothermal and thermal performance research.
- Thermal & additive design - Low-order heat-exchanger design and additive manufacturing constraints.
- Aerothermal engineering methods - Cross-cutting experiment, instrumentation, and CFD-experiment validation workflows.
- Applied aerodynamics - Field aerodynamics, wind resource assessment, and outdoor fluid systems linked to ventures and projects.
- Engineering notes - Reference material and methods documentation - instrumentation and turbomachinery clusters.
- 3-hole probe uncertainty - Uncertainty propagation for multi-hole pneumatic probes.
- Publications - Peer-reviewed papers and manuscripts in preparation - research pillar with thematic hubs, project links, and structured metadata.
- Projects - Selected engineering projects and outcomes.
- Engineering calculators - Air properties (live); probe uncertainty and related tools (planned).
- Turbomachinery deterioration - Rolls-Royce HPT leading-edge holing - aerothermal and thermal performance research.
- Fluid mechanics curriculum - Index and learning path across modules.
- Aerothermal engineering methods - Cross-cutting experiment, instrumentation, and CFD-experiment validation workflows.
- Technical notes
- Pneumatic probes overview
- 3-hole probe uncertainty note
Engineering knowledge platform
More tools, curriculum, notes, and research from the same body of work:
- Engineering - Central knowledge platform - tools, curriculum, notes, research, and applied engineering work.
- Collaborate - Industry advisory, aerothermal R&D collaboration, and venture partnerships.
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