Overview
ISO 17713-1:2007 - "Meteorology - Wind measurements - Part 1: Wind tunnel test methods for rotating anemometer performance" defines standardized wind tunnel test methods for evaluating rotating anemometers (cup and propeller types). The standard specifies unambiguous procedures to measure key performance characteristics - enabling consistent calibration, acceptance testing and comparison between models and manufacturers.
Key topics and technical requirements
- Scope: Applies to cup anemometers and propeller anemometers tested in a wind tunnel environment.
- Core measurements:
- Starting threshold (U0): lowest wind speed at which the anemometer continuously turns and produces a signal.
- Transfer function (Û = a + bR + …): relationship between wind speed and rotation rate/output; constants (a, b, …) are determined by least-squares regression across the instrument’s working range.
- Distance constant (L): distance the air flows while the rotor accelerates to 63% of equilibrium (measured at minimum at 5 m·s−1 and 10 m·s−1).
- Off-axis response ratio (Q): response at different angles of attack compared to an ideal cosine response; measured at specified angles and speeds (including 5 and 10 m·s−1).
- Acceptance testing: Defined procedures for testing production or delivered instruments against specified limits.
- Test apparatus & documentation: Requirements for wind tunnel conditions (see Annex A), measuring systems, recording techniques and test documentation.
- Quality metrics: Guidance on repeatability, measurement uncertainty and minimum number of runs (minimum three measurement sets, etc.).
- Notation and definitions: Clear definitions of symbols, terms and calculation methods to ensure traceability.
Practical applications and users
ISO 17713-1 is used by:
- Anemometer manufacturers for product development and factory acceptance testing.
- Calibration laboratories and test houses to perform standardized wind tunnel calibrations.
- Meteorological services, wind energy developers, aviation and air quality monitoring organizations to select and validate anemometers for field deployment.
- Procurement and compliance teams requiring documented performance characteristics for instrument selection.
Practical benefits include reliable model comparison, reproducible calibration data (transfer functions, starting thresholds, distance constants) and documented acceptance test results. Note: the standard cautions that wind tunnel results may differ from free-atmosphere performance and users should account for this when applying tunnel-derived parameters in the field.
Related standards
- ISO 5725-1 and ISO 5725-2 (accuracy, repeatability and reproducibility) - normative references used for evaluating measurement quality.
- ISO 17713 (other parts): Part 2 (planned) addresses wind vane test methods.
Keywords: ISO 17713-1:2007, rotating anemometer, wind tunnel test methods, cup anemometer, propeller anemometer, starting threshold, distance constant, transfer function, off-axis response, anemometer calibration, meteorology.