LWKD and Sound Propagation in the Surface Boundary Layer


  1. Forand, J.L.
Corporate Authors
Defence R&D Canada - Valcartier, Valcartier QUE (CAN)
The objective of this report is to demonstrate how DRDC Valcartier’s surface boundary layer model LWKD may be used to predict the vertical profile for the index of refraction or the refractivity, and the refractivity structure parameter for the propagation of sound waves through the air and over relatively flat land, ice or water. DRDC Valcartier’s LWKD model was originally developed to produce vertical profiles of air temperature, relative humidity, atmospheric pressure, and wind speed over water using Monin-Obukhov similarity theory. From the fundamental parameters obtained from its solution of the Monin-Obukhov similarity equations, the model determines structure parameters for temperature and humidity. From these parameters, it can also predict vertical profiles for the refractivity and the refractivity structure parameter, two of the most important parameters required to predict the propagation of electromagnetic radiation through the atmosphere. In its current version, it produces these values for optical, near infrared, mid-infrared and far-infrared wavelengths, and radio frequencies, but not for acoustical wavelengths. The report gives a brief introduction of LWKD with particular attention to details of importance to acoustic propagation in the atmosphere, discusses the speed of sound in moist air, the determination of the vertical refractivity profile for sound, and the determination of the refractivity structure parameter for sound. It discusses how to use the m

Il y a un résumé en français ici.

Report Number
DRDC-VALCARTIER-TR-2008-037 — Technical Report
Date of publication
01 Mar 2009
Number of Pages
Electronic Document(PDF)

Permanent link

Document 1 of 1

Date modified: