Open Access. Powered by Scholars. Published by Universities.®
- Institution
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen
Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen
Mechanical Engineering Theses
The objective of this study is to utilize shape optimization to enhance the performance of devices relying on acoustic wave propagation. Particularly, the shape of a horn speaker and an acoustic energy harvester were optimized to enhance their performance at targeted frequencies. High order Isogeometric Analysis (IGA) was performed to estimate the acoustic pressure with minimum geometry and pollution errors [1]. The analysis platform was then combined with Differential Evolution (DE) to optimize the geometry of the horn speaker and energy harvester at a given frequency. These cases effectively demonstrate two applications of Isogeomtric shape optimization for devices relying on …
Extending The Bandwidth Of Intensity-Based Sound Power Estimates, Michael C. Mortenson
Extending The Bandwidth Of Intensity-Based Sound Power Estimates, Michael C. Mortenson
Undergraduate Honors Theses
Sound power is often measured using the intensity-based engineering standard ANSI S12.12-1992:R2017. Traditional methods for intensity-based sound power estimation are limited in bandwidth at low frequencies by phase mismatch between microphones and at high frequencies by microphone spacing—with errors occurring well below the spatial Nyquist frequency. The Phase and Amplitude Gradient Estimation (PAGE) method has been used to extend the bandwidth of intensity calculations [1]. This thesis examines the efficacy of the PAGE method in overcoming bandwidth limitations in estimating sound power. Specifically, the sound fields from three sources—a blender, vacuum cleaner, and reference sound source—were measured according to ANSI …
Less-Than-Lethal Self Defense Device With An Acoustic Element, Anthony Taibi
Less-Than-Lethal Self Defense Device With An Acoustic Element, Anthony Taibi
KSU Journey Honors College Capstones and Theses
This creative capstone project involves the conception, design, and creation of a less-than-lethal self defense device with an integrated sound board to control the acoustic element. Theoretically, this device is capable of deterring potential threats without causing any serious harm or any long-term damage. When starting this project, I was very focused on sonic warfare, and how to harness the power of ultrasonic and infrasonic sound waves to subdue to target; however, I concluded that using resonant frequencies to deter a human being is too dangerous, expensive, and can have negative effects for the user of the device if used …
Comparative Study And Design Of Economical Sound Intensity Probe, Karan Gundre
Comparative Study And Design Of Economical Sound Intensity Probe, Karan Gundre
Dissertations, Master's Theses and Master's Reports
The theory of sound intensity measurement using the two-microphone method was first developed in the late 1970s. Even though the measurements were limited by the technology of the time, the theory was straight-forward and considerable attention was given to improving precision during testing or post-processing. With the development of modern equipment, however, the focus shifted to the apparatus. The commercial intensity probes available today have microphones that are already phase-matched. This eliminates the need for correction during or post-testing as a majority of the errors are minimized before any data is even collected. Although such intensity probes facilitate taking precise …