Accession Number:

ADA172960

Title:

A Numerical Method for Unfolding the Stabilized Nuclear Cloud Particle Distribution

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s):

• Felty, James R.

Report Date:

1986-03-01

Pagination or Media Count:

130.0

Abstract:

A numerical unfolding of particle size distribution from reduced airborne filter sample data is developed. First stabilized nuclear cloud is modeled using a trial particle size distribution that is positioned in the atmosphere by empirical relationships. Then Davies-McDonald fall mechanics are used to model the falling particles in the cloud. The amount of mass at each sample altitude at each sample time is calculated from the cloud model and compared to the amount of mass found in actual cloud samples. When the calculated masses equal the actual masses, the particle distribution used to construct the stabilized cloud is the correct one. A computer code for this numerical analysis is tested using hypothetical filter sample data constructed from a known particle size distribution. An input parameter sensitivity analysis is also conducted. Actual nuclear cloud sample data from the Redwing series ZUNI shot is analyzed using this numerical method of airborne nuclear cloud sample analysis. The outcome of the ZUNI sample analysis is somewhat inconclusive in that it does not pinpoint a distribution. However, results of the model sensitivity analysis indicate that the particle size distribution of the stabilized ZUNI cloud may be lognormal with a log-slope between 2.9 and 3.9.

Descriptors:

• *FALLOUT
• *NUCLEAR CLOUDS
• PARTICLE SIZE
• STABILITY
• AIRBORNE
• NUMERICAL ANALYSIS
• AIR FILTERS
• SENSITIVITY
• DATA REDUCTION
• SAMPLING
• MATHEMATICAL MODELS
• COMPUTER PROGRAMS
• THESES

Subject Categories:

• Radioactivity, Radioactive Wastes and Fission Products

Distribution Statement:

APPROVED FOR PUBLIC RELEASE