User's Reference Guide for Noise Assessment Prediction System (NAPS)
Abstract
The noise assessment and prediction system (NAPS) model provides an estimate of the surface peak noise intensity in all directions surrounding a blast source using a personal computer. An essential feature of the model is its ability to account for meteorological and topographical variations in the calculation of blast sound propagation. In performing noise intensity estimates, acoustic ray traces are generated over a sufficient range of azimuth and elevation angles to define the focusing and shadow regions in the area surrounding the airblast. The acoustics of the model include the effects of spherical acoustic spreading, absorption, focusing, shadow zones, reflection of rays from water, interference of multiple rays arriving at the same location, and the directional asymmetry of a blastwave. The NAPS model has been implemented at Aberdeen Proving Ground, Maryland, using acoustic sounder, upper air, and surface station data to provide on-line meteorological input. Plots of ray trace trajectories and sound intensity contour levels on a background map of the Aberdeen area, along with tabular data, are included as model features. This user's reference guide describes the procedures for running the NAPS model. It also includes examples of the required input data files and examples of the graphic outputs generated by the model.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1992
- Accession Number
- ADA258865
Entities
People
- James K. Luers
- Joyce A. Smith
- Mark A. Dietenberger
Organizations
- University of Dayton