DESIGN CONCEPT STUDY FOR A WIND PROFILE INSTRUMENT.
Abstract
This study was made to determine the feasibility of applying the electromagnetic-acoustic (EMAC) probe concept to the remote measurement of low altitude wind profiles. The EMAC probe determines air velocity by measuring the Doppler frequency shift in an electromagnetic wave reflected from an acoustic disturbance propagating in the atmosphere. This measured velocity is composed of the local sound velocity and the component of wind velocity in the direction of acoustic propagation. The velocity of sound can be determined and subtracted, leaving one component of wind velocity. Two such measurements in appropriately different directions can be combined vectorially to give horizontal wind speed and direction. An analysis was made to determine the macimum ranges which might be expected for probes operating in different frequency bands. Several probe configurations were evaluated for their suitability to wind profile measurements, and an error analysis was made to determine the accuracy of each configuration. In each analysis, it was assumed each individual probe would have a maximum error of 0.5 mph in measuring the velocity of the acoustic wave. From investigations to date, this appears to be a reasonable figure for the accuracy expected.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 06, 1961
- Accession Number
- AD0610547
Entities
People
- P. L. Smith Jr.
- R. W. Fetter
- V. Klein
Organizations
- MRIGlobal