Award Date


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Mechanical Engineering

First Committee Member

Douglas Reynolds

Second Committee Member

Brendan O'Toole

Third Committee Member

Darrell Pepper

Fourth Committee Member

Evangelos Yfantis

Fifth Committee Member

Samaan Ladkany

Number of Pages



The design objectives for HVAC air distribution systems are thermal comfort, good indoor air quality, energy efficiency, low construction cost, and appropriate indoor noise levels. The last objective requires that the designer can predict the attenuation of sound transmitted through an air duct. One form of attenuation commonly introduced to an air distribution system to achieve interior noise criteria is fiberglass liner. Past research has been conducted to obtain reliable and accurate insertion loss (IL) data for duct with fiberglass liner. Empirical efforts have relied on limited data sets. Computational efforts have produced numerical models that are not practical for everyday use by practicing designers. The most recent research in this subject, funded by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and completed at the University of Nevada, Las Vegas (UNLV), produced considerable IL data based on laboratory measurement. A set of 96 regression equations were developed to predict the IL of ducts with fiberglass liner. The equations and long tables of coefficients did not include frequency as an independent variable. This research project studies the data further and provides new deterministic models that have frequency as an independent variable. Further, these models include equations that predict the level and frequency of the peak IL.


duct lining; duct noise; fiberglass lining; HVAC noise control; sound attenuation; sound insertion loss


Acoustics, Dynamics, and Controls | Architectural Engineering | Mechanical Engineering

File Format


File Size

16000 KB

Degree Grantor

University of Nevada, Las Vegas




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