Wind Tunnel Standards
Wind tunnels were originally used to test the aerodynamic properties of aircraft. Their use has expanded to testing wind turbines, cars and a host of other items such as scale replicas of entire buildings.
What are the primary standards wind tunnels must meet? And what are the major standards for wind tunnel testing?
SAE Wind Tunnel Standards
SAE was originally the Society of Automotive Engineers. Now called SAE International, it has issued a host of standards on the use of wind tunnels for automotive and structural tests.
Wind tunnels are used to simulate aerodynamic drag on vehicles, provide estimates of miles per gallon consumed in less than ideal conditions, test windshield wiper performance in rain and sleet and test how vehicles withstand heavy gusts.
SAE J2881 measures the aerodynamic performance of light trucks and sedans. SAE J1252 is the recommended practice for testing trucks and buses in wind tunnels.
SAE J2084 is the test procedure for testing the aerodynamics of road vehicles like diesel trucks and school buses. This standard can be used when testing the aerodynamic drag of a vehicle or its response to heavy wind gusts.
SAE J2777 gives the recommended practices for adjusting wind tunnels to match climatic conditions so that they are similar to test conditions at other wind tunnel facilities. SAE J953 is the procedure for testing backlight defogging systems. This testing can be performed in a wind tunnel or a large, cold room.
SAE J2071 gives the adjustments to be used to adjust wind tunnel test results to estimates of real-world performance in regards to surface pressures and aerodynamic moments.
SAE AIR5666 is an Aerospace Information Report. This report, published in 2012, compares different icing wind tunnels to each other. SAE AIR 5687 or Aerospace Information Report 5687 reviews the scaling issues found in testing engines and inlets in wind tunnels compared to in flight testing.
SAE ARP 5905 is an Aerospace Recommended Practice or ARP. ARP 5905 includes recommendations for calibrating icing wind tunnels used in testing aircraft and aircraft sections like wings. SAE ARP 5905 was published in 2003.
ISO Wind Tunnel Standards
ISO 17713 gives the procedure for testing anemometers in a wind tunnel. ISO 22856 measures the relative drift of sprayed water from nozzles inside of a wind tunnel.
ISO 4354 gives the test procedure for determining wind load on buildings.
ISO 10521-1 is the procedure for road load using a dynamometer in a wind tunnel. ISO 10521-2 is the test procedure using reference atmospheric conditions. This information is used to estimate fuel consumption under different driving conditions.
ASTM Wind Tunnel Standards
ASTM C1569-03 is the test procedure for measuring how well concrete and clay roof tiles resist the wind. ASTM D5336-96 describes the process of testing the performance of a wind vane in a wind tunnel.
ASTM D5096-02 is the procedure for determining the performance of anemometers inside of wind tunnels.
ASTM D4430-00 is the test procedure for determining the comparability of meteorological measurements in different wind tunnels and environmental chambers. This comparability is necessary because the environmental conditions change throughout the testing cycle and between testing facilities.
ASTM E459-05 is the test procedure for measuring heat transfer with a calorimeter. This test can be performed inside of a wind tunnel, though care must be taken to ensure that the thin skin calorimeter does not change shape in response to the air flow, wince this will affect the test results.
AIAA Wind Tunnel Standards
American Institute of Aeronautics and Astronautics standard AIAA G129 gives a recommended nomenclature for wind tunnel testing. AIAA G129 includes a recommended axis system that can be used in all wind tunnels.
Structural Engineering Institute standard SEI 49 describes how structures should be tested in a wind tunnel to determine their wind load. This information is used to determine how well - and if - buildings can withstand high winds. The SEI 49 standard was issued jointly with the American Society of Civil Engineers and Structural Engineering Institute.