Publication:
Tortuosity index based on dynamic mechanical properties of polyimide foam for aerospace applications

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Authors
Flores-Bonano, Sugeily
Vargas-Martinez, Juan C.
Suárez, O. Marcelo
Silva-Araya, Walter
Embargoed Until
Advisor
College
College of Engineering
Department
Department of Materials Science and Engineering
Degree Level
Publisher
MDPI
Date
2019-06-07
Abstract
The determination of a reliable tortuosity index is lacking in the aerospace industry. Therefore, a methodology is formulated via direct and indirect characterization methods of a fluid-filled porous media. Chemical, thermal, and mechanical characterization was performed to the PolyuMAC(TM) polyimide foam. Tortuosity was measured considering a pressure difference as the resistivity variable, rather than electrical resistivity or molecular diffusivity, as proposed on previous models. This is an empirical establishment of the tortuosity index considering the correlation among hydraulic and structural dimensionless parameters obtained through the Buckingham’s Pi theorem. The behavior of the polyimide was studied for samples of different lengths compressed at 30%, 60%, and 90% of its original length on the foaming direction. Results show that, porosity, sample length, and fluid viscosity are relevant for the insulation performance of the material. Regression analysis produced a significant statistical model fit to the data correlated from the dimensionless parameters for each dynamic compression series.
Keywords
Tortuosity index,
Polyimide foam,
PolyuMAC(TM),
Aerospace material
Usage Rights
Except where otherwise noted, this item’s license is described as Attribution-NonCommercial-ShareAlike 3.0 United States
Cite
Flores-Bonano, S., Vargas-Martinez, J. C., Suárez, O. M., & Silva-Araya, W. (2019). Tortuosity index based on dynamic mechanical properties of polyimide foam for aerospace applications [Article]. MDPI. Retrieved from https://hdl.handle.net/20.500.11801/2819