The SODAR
نویسندگان
چکیده
SODAR stands for SOund Detection And Ranging. A SODAR uses sound pulses at a frequency of about 2kHz to detect turbulence and measure wind speeds. Turbulence in the atmosphere reflects a portion of the acoustic energy back towards the ground. The SODAR measures the strength, time delay and doppler shift of these echoes. The time delay of the echo determines the height from which the echo returned, the echo strength provides a measure of the strength of the turbulence at that height and the frequency shift of the echo allows determination of the wind speed parallel to the direction of the emitted signal.
منابع مشابه
Classification of Sodar Data Using Fractal Features
Geometric shape features extracted from sodar data have been used to classify different atmospheric patterns. But such features are scale dependent. In this paper, an attempt is made to classify sodar data using fractal features. Results show that scale invariance of fractal features make them quite useful for classification of sodar patterns.
متن کاملRemote Sensing of Wind
Remote sensing by LIDARs and SODARs is now ubiquitous in the wind energy industry, but both these technologies are still rapidly changing. What accuracy and reliability can today be expected from SODAR wind measurements? Is there traceable evidence for performance? Environmental factors, turbulent fluctuations and non-uniform terrain all affect the wind speed uncertainty. So site-to-site variat...
متن کاملA Time Series Sodar Simulator Based on Large-Eddy Simulation
A sodar simulator capable of producing time series data emulating sodar signals has been developed and tested. The atmospheric fields used to populate the sodar simulator are taken from output of a large-eddy simulation code. The characteristics of the sodar (number and zenith angle of beams, beamwidth, transmit frequency, range resolution, etc.) are defined by the user to allow emulation of ex...
متن کاملSodar Comparison Methods for Compatible Wind Speed Estimation
This thesis includes the results of a PhD study about methods to compare Sonic Detection And Ranging (SODAR) measurements to measurements from other instruments. The study focuses on theoretical analysis, the design of a transponder system for simulating winds and the measurement of the acoustic radiation patterns of SODARs. These methods are integrated to reduce uncertainty in SODAR measuremen...
متن کاملComparison between Measurements Obtained with a Meteorological Mast and a Rass Sodar
Data of wind speed, wind direction and temperature obtained from a meteorological mast and a RASS sodar are contrasted. Wind data were compared at a height of 100 m and temperature at 51 and 100 m. 10 minute averages during the month of April 2001 were used. Wind speeds showed satisfactory correlation and the temperature fit was better at 100 m than at 51 m. Mast data were steadier than those f...
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