Examination of a Correction Procedure for the Flow Attenuation in Orthogonal Sonic Anemometers
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In this study we examine the calibration of wind speed measured by a sonic anemometer, with an orthogonal probe configuration, with regard to the approximation of the flow angle, and the wind-speed dependence of the flow attenuation attributed to the transducer shadow. The flow angle θ should be calculated by the iterative method when the attenuation is relatively high. For a probe manufactured by Kaijo Co. TR-61C, the wind-speed dependence of the transducer shadow effect is formulated from the results of the wind-tunnel experiment. Assuming the equation is applicable to field observations, significant errors possibly remain especially when the wind speed is low, and /or the angle between the flow vector and the sonic path is small, if the wind-speed dependence in measurement errors is neglected.
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- Coppin, P.A. and Taylor, K. J.: 1983, ‘A Three-Component Sonic Anemometer/Thermometer System for General Micrometeorological Research’, Boundary-Layer Meteorol. 27, 27-42.Google Scholar
- Hanafusa, T., Fujitani, T., Kobori, Y., and Mitsuta, Y.: 1982, ‘A New Type Sonic Anemometer-Thermometer for Field Operation’, Pap. Meteorol. Geophys. 33, 1-19.Google Scholar
- Kaimal, J. C.: 1988, ‘The Atmospheric Boundary Layer — Its Structure and Measurement’, translated in Japanese by Mitsuta, Y. and Yamada, M., Gihodo Publ. Co., 116 pp.Google Scholar
- Kaimal, J. C. and Gaynor, J. E.: 1983, ‘The Boulder Atmospheric Observatory’, J. Appl. Meteorol. 22, 863-880.Google Scholar
- Kaimal, J. C., Gaynor, J. E., Zimmerman, H. A., and Zimmerman, G. A.: 1990, ‘Minimizing Flow Distortion Errors in a Sonic Anemometer’, Boundary-Layer Meteorol. 53, 103-115.Google Scholar
- Kondo, J. and Sato, T.:1982, ‘The Determination of the Von Karman Constant’, J. Meteorol. Soc. Japan 60, 461-471.Google Scholar
- Kraan, C. and Oost, W. A.: 1989, ‘A New Way of Anemometer Calibration and its Application to a Sonic Anemometer’, J. Atmos. Oceanic Tech. 6, 516-524.Google Scholar
- Mortensen, N. G.: 1994, ‘Flow-Response Characteristics of the Kaijo Denki Omni-Directional Sonic Anemometer (TR-61B)’, Risφ-R-704(EN), 32 pp.Google Scholar
- Wyngaard, J. C.: 1981, ‘The Effects of Probe-Induced Flow Distortion on Atmospheric Turbulence Measurements’, J. Appl. Meteorol. 20, 784-794.Google Scholar
- Wyngaard, J. C.: 1986, ‘Flow-Distortion Effects on Scalar Flux Measurements in the Surface Layer: Implications for Sensor Design’, Boundary-Layer Meteorol. 42, 19-26.Google Scholar
- Wyngaard, J. C. and Zhang, S. F.: 1985, ‘Transducer-Shadow Effects on Turbulence Spectra Measured by Sonic Anemometer’, J. Atmos. Oceanic Tech. 2, 548-558.Google Scholar