Accession Number:

AD0781259

Title:

A Numerical Study of Clearing Warm Fog by Using Hygroscopic Seeding in Conjunction with Helicopter Downwash

Descriptive Note:

Technical paper

Corporate Author:

NAVAL ENVIRONMENTAL PREDICTION RESEARCH FACILITY MONTEREY CA

Personal Author(s):

• Tag, Paul M.

Report Date:

1974-05-01

Pagination or Media Count:

46.0

Abstract:

Several techniques for dissipating warm fog have been tried in field experimentation. In an attempt to augment helicopter downwash dissipation efforts, hygroscopic seeding has been suggested. However, because these two techniques work in very different time frames, the question arises as to whether they can be used together simultaneously. By simulating a helicopter downwash profile, a two-dimensional vorticity model is used to determine seeding material concentrations produced as the result of dispensing material into the downwash. Continuous seeding while hovering, pulse seeding while hovering, and the effect of helicopter movement are examined.

Descriptors:

• *FOG
• *WEATHER MODIFICATION
• CLOUD SEEDING
• DISSIPATION
• DOWNWASH
• FLOW RATE
• HELICOPTERS
• HYGROSCOPICITY
• MATHEMATICAL MODELS
• PARTICLES
• SIMULATION
• TWO DIMENSIONAL FLOW
• VISIBILITY

Subject Categories:

• Meteorology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE