Development of a Microburst Turbulence Model for the Joint Airport Weather Studies Wind Shear Data.
Abstract
A turbulence model is developed to supplement the microburst quasi-steady wind shear model established earlier from the JAWS Doppler radar data sets. The wind shear model is, in effect, a quasi-steady, spatially varying wind field. The spatial scale of the wind variation is on the order of 500-750 ft (150-200 m). Airborne sensor response (i.e., angle of attack, stall warning, pitot tubes, etc,), structural dynamics, pilot workload, and other such factors, however, respond to much higher frequency wind effects. To account for these effects, a 'first-cut' turbulence model based on Doppler radar second moment data is presented. Superimposing the turbulent fluctuation from this turbulence model on the quasi-steady JAWS wind field is believed to provide a more realistic simulation of the microburst flow for aviation application. The Doppler radar second moments of spectral width data from the June 30, July 14, and August 5, 1982, JAWS microburst measurements are analyzed in considerable detail. Microburst turbulence intensity is calculated by subtracting the spectral width broadenings due to wind shear, antenna motion, and precipitation fall speeds from the radar spectra width. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1987
- Accession Number
- ADA185877
Entities
People
- Ho-pen Chang
- Walter Frost