Presentation Title

The Abatement of Noise in Aircraft Gas Turbine for Increased Passenger Comfort

Location

Nessmith-Lane Atrium

Session Format

Poster Presentation

Research Area Topic:

Engineering and Material Sciences - Mechanical

Abstract

Humans have a hearing range of 20 Hz to 20,000 Hz. However, if amplitudes reach strong enough levels serious and often life changing damage can occur. In some cases hearing loss can occur through noise induced hearing loss from continuous exposure in aerospace industries.

This research explores the harshness of sound generated by an aircraft turbine at 60,000 rpm, up to 75,000 rpm in 5,000 rpm increments. The microphone used is a state-of-the-art Bruel and Kjaer multi-field microphone, and Pulse signal processing platform. In a previous presentation, a baseline and melamine was measured and recorded using a Noise Reduction Coefficient tests by measuring the sound levels at certain frequencies. In this presentation a polyurethane foam that is denser than melamine and lighter than cotton composites, will be compared to melamine. However, because of goal of reducing damage to passenger ears an aircraft gas turbine will be used as a sound source rather than a speaker connected to a function generator. Constant Percentage Bandwidth, CPB, analysis was done using the Bruel and Kjaer Pulse signal processing platform at A weighting. At 70,000 rpm and 65,000 rpm the polyurethane foam performed better than the melamine foam in the higher frequencies. Because humans can only tell a difference in sound by three decibels the differences, starting at 1,000 Hz, were considered noticeable when there was a difference in performance by three decibels or greater. At all test speeds, the polyurethane foam performed better than the melamine foam at 1,000 Hz and greater.

At the end of this test it was noticed that the polyurethane foam performed better than melamine. This achieved the goal because polyurethane can be originated from an organic material such as soy or vegetable oils. This is also a better material because of the density that it has. It has the potential to maybe have one or two layers of this foam rather than three or four layers of melamine, which can be heavier.

Presentation Type and Release Option

Presentation (Open Access)

Start Date

4-16-2016 2:45 PM

End Date

4-16-2016 4:00 PM

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Apr 16th, 2:45 PM Apr 16th, 4:00 PM

The Abatement of Noise in Aircraft Gas Turbine for Increased Passenger Comfort

Nessmith-Lane Atrium

Humans have a hearing range of 20 Hz to 20,000 Hz. However, if amplitudes reach strong enough levels serious and often life changing damage can occur. In some cases hearing loss can occur through noise induced hearing loss from continuous exposure in aerospace industries.

This research explores the harshness of sound generated by an aircraft turbine at 60,000 rpm, up to 75,000 rpm in 5,000 rpm increments. The microphone used is a state-of-the-art Bruel and Kjaer multi-field microphone, and Pulse signal processing platform. In a previous presentation, a baseline and melamine was measured and recorded using a Noise Reduction Coefficient tests by measuring the sound levels at certain frequencies. In this presentation a polyurethane foam that is denser than melamine and lighter than cotton composites, will be compared to melamine. However, because of goal of reducing damage to passenger ears an aircraft gas turbine will be used as a sound source rather than a speaker connected to a function generator. Constant Percentage Bandwidth, CPB, analysis was done using the Bruel and Kjaer Pulse signal processing platform at A weighting. At 70,000 rpm and 65,000 rpm the polyurethane foam performed better than the melamine foam in the higher frequencies. Because humans can only tell a difference in sound by three decibels the differences, starting at 1,000 Hz, were considered noticeable when there was a difference in performance by three decibels or greater. At all test speeds, the polyurethane foam performed better than the melamine foam at 1,000 Hz and greater.

At the end of this test it was noticed that the polyurethane foam performed better than melamine. This achieved the goal because polyurethane can be originated from an organic material such as soy or vegetable oils. This is also a better material because of the density that it has. It has the potential to maybe have one or two layers of this foam rather than three or four layers of melamine, which can be heavier.