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Abstract Due to fiber swelling, textile fabrics containing hygroscopic fibers tend to decrease pore size under wet or increasing humidity and moisture conditions, the reverse being true. Nevertheless, for personal thermal regulation and comfort, the opposite is desirable, namely, increasing the fabric pore size under increasing humid and sweating conditions for enhanced ventilation and cooling, and a decreased pore size under cold and dry conditions for heat retention. This paper describes a novel approach to create such an unconventional fabric by emulating the structure of the plant leaf stomata by designing a water responsive polymer system in which the fabric pores increase in size when wet and decrease in size when dry. The new fabric increases its moisture permeability over 50% under wet conditions. Such a water responsive fabric can find various applications including smart functional clothing and sportswear. Graphical Abstract
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Investigating the Aeroacoustic Properties of Porous Fabrics
The aeroacoustic properties of porous fabrics are investigated experimentally with the goal of finding a fabric that serves as an improved interface between wind tunnel flow and quiescent conditions. A total number of eight porous fabrics were investigated, namely, four glass fiber fabrics, two plain-weave Kevlar fabrics, and two modified plain Kevlar fabrics with their pores irregularly clogged. Two custom-made rigs were used to quantify the transmission loss (TL) and self-noise of all fabrics. The pores were found to serve as a low-resistance gateway for sound to pass through, hence enabling a low TL. The TL was found to increase with decreasing open area ratio (OAR), whereas other fabric properties had a minor impact on TL. The thread density was found to be a primary factor in determining the frequency range of porous fabrics’ self-noise, with the OAR potentially playing a secondary role in the self-noise levels. Fabrics with irregular pore distribution showed a more broadband self-noise signature associated with lower frequencies compared to fabrics with periodic pore patterns. Overall, fabrics with an irregular pore distribution or fabrics with increased thread density were identified as two potential ways to obtain superior aeroacoustic behavior compared to commonly used Kevlar fabrics.
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- Award ID(s):
- 2012443
- PAR ID:
- 10317512
- Date Published:
- Journal Name:
- AIAA Journal
- ISSN:
- 0001-1452
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.2514/1.J061385
