Olive Tree Lab Terrain

Overview

Olive Tree Lab Terrain is an acoustics software application developed and published by Mediterranean Acoustics. Olive Tree Lab Terrain can be used for noise barrier design and small to medium scale noise mapping. The latest available version is 1.3.^{[1] [2][3]}.

Calculation Methods

Olive Tree Lab Terrain uses the following methods and their limitations:

* Hadden & Pierce Diffraction 3D model implemented with finite impedances faces using Salomons semi-analytical method including ground effects. Multiple barrier diffraction is calculated in a recursive way at any diffraction order.
* In-house sound path detection and ray tracing methods.
* Ground effect using the One Parameter Theory of Chessell based on Delany and Bazley 
* Reflections from finite surfaces based on Clay–Medwin’s work to include Fresnel zones contribution at any order level. 
* Atmospheric absorption based on ISO 9613 -1. 
* Turbulence coherence factor based on HARMONOISE WP3

Version History

Version 1.2

Version 1.2 included ^[4]

• Bug Fixes
• Path Detection Optimization
• Calculation Optimization
• Memory Management Optimization
• Performance Optimization
• User Interface Optimization
• Sound Diffraction Method Calculation Option removal.
• Issue (e) of Version 1.1 release notes has been resolved.
• Double sided surfaces became redundant. Calculations take place on any single sided surface, no matter where the normal of the surface points at.
• Validation based on scientific publications.

Version 1.3

Version 1.3 includes ^[5]

• Bug Fixes
• Mapping Legends show the levels in incremental steps of 10 dB
• LpAfter and LpBefore mappings are displayed in dBA values
• Octave measurement import in noise source addition is now converted to 1/3 octave values before added to database
• Database location changed.

References

Notes

1. ^ http://www.otlterrain.com
2. ^ Steven G Mattson; Stephen E. Polakowski, Jeff Pruetz, Rob Smith, Phil Janicki (9-11 August 2011). "Real Time Urban Acoustics Using Commercial Technologies". 2011 NDIA GROUND VEHICLE SYSTEMS ENGINEERING AND TECHNOLOGY SYMPOSIUM. 
3. ^ Panos Economou; Panagiotis Charalampous, Stefanos Ioannides, Polykarpos Polykarpou (September 18-21 2011). "The Significance of Sound Diffraction Effects in Predicting Acoustics in Ancient Theaters". The Acoustics of Ancient Theatres Conference. pp. Patras. 
4. ^ http://www.environmental-expert.com/software/otl-terrain-147193
5. ^ http://www.environmental-expert.com/software/otl-terrain-147193