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Title: Revisiting wind speed measurements using actively heated fiber optics: a wind tunnel study
Abstract. Near-surface wind speed is typically only measured by point observations. The actively heated fiber-optic (AHFO) technique, however, has thepotential to provide high-resolution distributed observations of wind speeds, allowing for better spatial characterization of fine-scaleprocesses. Before AHFO can be widely used, its performance needs to be tested in a range of settings. In this work, experimental results on thisnovel observational wind-probing technique are presented. We utilized a controlled wind tunnel setup to assess both the accuracy and the precisionof AHFO under a range of operational conditions (wind speed, angles of attack and temperature difference). The technique allows for wind speedcharacterization with a spatial resolution of 0.3 m on a 1 s timescale. The flow in the wind tunnel was varied in a controlledmanner such that the mean wind ranged between 1 and 17 m s−1. The AHFO measurements are compared to sonic anemometer measurements andshow a high coefficient of determination (0.92–0.96) for all individual angles, after correcting the AHFO measurements for the angle ofattack. Both the precision and accuracy of the AHFO measurements were also greater than 95 % for all conditions. We conclude that AHFO has thepotential to measure wind speed, and we present a method to help choose the heating settings of AHFO. AHFO allows for the characterization ofspatially varying fields of mean wind. In the future, the technique could potentially be combined with conventional distributed temperature sensing(DTS) for sensible heat flux estimation in micrometeorological and hydrological applications.  more » « less
Award ID(s):
1832170
PAR ID:
10214591
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Atmospheric Measurement Techniques
Volume:
13
Issue:
10
ISSN:
1867-8548
Page Range / eLocation ID:
5423 to 5439
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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