approximately the area covered by turbulence the cup anemometer rotating cups. intensity. A set of measurements shall be Check for details made and the linear regression of two pitot tubes between the dynamic pressures used for the measured by the two pitot tubes purpose and shall be calculated. The difference verification that shall be less than 0.2%. The axial they are identical turbulence intensity at the anemometer's position shall be below 2%. 13 page 58, The wind tunnel calibration factor, Check for the paragraph which gives the relation between details of 6, line 1 the conditions at the reference assessment of measurement position and those at wind tunnel the anemometer position, shall be calibration factor. appraised using pitot tubes. 14 page 59, The facility shall undergo a detailed Check for all the paragraph examination of the repeatability of details required to 1, line 1 anemometer calibration. The facility repeat the shall designate a reference anemometer anemometer for use in these tests. calibration The reference anemometer shall be Check for details used only for checking performance of the designated of this and other anemometer reference facilities. anemometer for the facility 15 page 59, The repeatability examination shall Check for details paragraph include at least 5 calibrations of the from 5 calibrations 1, line 4 reference anemometers (over performed on various atmospheric conditions). reference The maximum difference between anemometer calibrations should be less than during 0.5% at 10 m/s wind speed. The repeatability process shall be repeated after any examination. modification or recalibration of the Check for the facility. measure of difference between 5 calibrations Check for details of any modifications or recalibration of the test facility. 16 page 59, The facility shall prove, through Check for details paragraph round robin testing, that its results of round robin 2, line 1 are comparable with other tests. anemometer calibration facilities. Clause F.3: Instrumentation and calibration set-up requirements.
approximately the area covered by the cup anemometer rotating cups. A set of measurements shall be made and the linear regression between the dynamic pressures measured by the two pitot tubes shall be calculated. The difference shall be less than 0.2%. The axial turbulence intensity at the anemometer's position shall be below 2%. turbulence intensity. Check for details of two pitot tubes used for the purpose and verification that they are identical 13 page 58, paragraph 6, line 1 The wind tunnel calibration factor, which gives the relation between the conditions at the reference measurement position and those at the anemometer position, shall be appraised using pitot tubes. Check for the details of assessment of wind tunnel calibration factor. 14 page 59, paragraph 1, line 1 The facility shall undergo a detailed examination of the repeatability of anemometer calibration. The facility shall designate a reference anemometer for use in these tests. The reference anemometer shall be used only for checking performance of this and other anemometer facilities. Check for all the details required to repeat the anemometer calibration Check for details of the designated reference anemometer for the facility 15 page 59, paragraph 1, line 4 The repeatability examination shall include at least 5 calibrations of the reference anemometers (over various atmospheric conditions). The maximum difference between calibrations should be less than 0.5% at 10 m/s wind speed. The process shall be repeated after any modification or recalibration of the facility. Check for details from 5 calibrations performed on reference anemometer during repeatability examination. Check for the measure of difference between 5 calibrations Check for details of any modifications or recalibration of the test facility. 16 page 59, paragraph 2, line 1 The facility shall prove, through round robin testing, that its results are comparable with other anemometer calibration facilities. Check for details of round robin tests. Clause F.3: Instrumentation and calibration set-up requirements.
od-551-11ed.1.0.docx