Ragimana, PhumudzoDikgale, Moyahabo SMabeko, Philimon K2026-01-272026-01-272025-09http://hdl.handle.net/10204/14651Accurate measurement of wind speed is essential for effective assessment of wind resources and evaluation of turbine performance within the wind energy industry. This paper details the characterization of the Council for Scientific and Industrial Research (CSIR) open-jet 2-meter wind tunnel, which is designed to facilitate MEASNET-compliant calibration of cup anemometers in line with IEC 61400. The test section underwent a rigorous evaluation to determine flow uniformity, turbulence intensity, and both axial and vertical flow alignment, utilizing a grid of calibrated pitot tubes. Measurements were taken across various horizontal and vertical planes to evaluate the spatial velocity distribution and confirm compliance with international calibration standards. The open-jet design presents distinct aerodynamic challenges, especially in maintaining low turbulence and uniform velocity profiles in the wind tunnel test section. Through a process of iterative flow conditioning and systematic testing, the tunnel achieved velocity deviations within ±0.03 m/s, thereby complying with the rigorous criteria for high-precision anemometer calibration. Repeatability tests conducted with a reference anemometer, along with assessments of environmental stability, further substantiated the wind tunnel's performance under different ambient conditions. The findings affirm the tunnel's capability as a national calibration facility, providing traceable and internationally recognised wind speed measurement capabilities. This characterisation establishes a basis for future improvements, including broader calibration ranges, automated testing rigs, and integrated uncertainty modelling to meet the increasing demands of the wind energy sector. This characterisation lays the groundwork for future upgrades, like wider calibration ranges, automated calibration systems, and better uncertainty modelling, to keep up with the growing needs of accurate measurements within the wind energy industry.FulltextenWind tunnel characterisationCup anemometer calibrationFlow uniformityPitot tube measurementsConference PresentationN/A