On the dynamic drag coefficient for wave propagation through fluid‐saturated highly porous open‐cell foams

1997 ◽  
Vol 101 (5) ◽  
pp. 3146-3146
Author(s):  
Robert E. Slade ◽  
Keith Walton ◽  
Colin A. Mead ◽  
Alan T. Parsons ◽  
Roger J. Pinnington ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Drag Coefficient ◽  
Open Cell ◽  
Open Cell Foams ◽  
Highly Porous

Elastic Wave Propagation in Open-Cell Foams

2019 ◽  
Vol 86 (5) ◽  
Author(s):  
Alireza Bayat ◽  
Stavros Gaitanaros
Keyword(s):  
Wave Propagation ◽  
Elastic Wave ◽  
Finite Size ◽  
Bloch Wave ◽  
Elastic Wave Propagation ◽  
Surface Evolver ◽  
Dynamic Simulations ◽  
Element Analysis ◽  
Open Cell ◽  
Open Cell Foams

This work examines elastic wave propagation phenomena in open-cell foams with the use of the Bloch wave method and finite element analysis. Random foam topologies are generated with the Surface Evolver and subsequently meshed with Timoshenko beam elements, creating open-cell foam models. Convergence studies on band diagrams of different domain sizes indicate that a representative volume element (RVE) consists of at least 83 cells. Wave directionality and energy flow features are investigated by extracting phase and group velocity plots. Explicit dynamic simulations are performed on finite size domains of the considered foam structure to validate the RVE results. The effect of topological disorder is studied in detail, and excellent agreement is found between the wave behavior of the random foam and that of both the regular and perturbed Kelvin foams in the low-frequency regime. In higher modes and frequencies, however, as the wavelengths become smaller, disorder has a significant effect and the deviation between regular and random foam increases significantly.

Development of Bio-Based Foams With Improved Acoustic and Mechanical Performance

2012 ◽  
Author(s):  
Shahrzad Ghaffari Mosanenzadeh ◽  
Hani E. Naguib ◽  
Chul B. Park ◽  
Noureddine Atalla
Keyword(s):  
Mechanical Characteristics ◽  
Mechanical Performance ◽  
Water Soluble ◽  
Huge Amount ◽  
Open Cell ◽  
Acoustic Performance ◽  
Foam Morphology ◽  
Open Cell Foams ◽  
Weak Structure ◽  
Highly Porous

Interest in noise control has been growing in recent years and efforts are under way to improve the acoustic performance of existing sound absorbers and also to replace the non-recyclable ones with environmentally friendly materials. Present study describes the research on fabrication, improvement of acoustic absorption and enhancement of mechanical strength of bio-based open-cell foams. Through this study, highly porous open-cell Polylactide (PLA) foams were fabricated by a new fabrication method combining particulate leaching technique and compression molding. Foamed structures were fabricated with PLA and Polyethylene glycol (PEG) with salt as the particulate. Pore size of the foam was controlled by salt particulates and higher interconnectivity was achieved by the co-continuous blending morphology of PLA matrix with water-soluble PEG. As a result of novel secondary porous structure, acoustic performance of PLA foams was successfully improved. One issue with application of bio-based open-cell foams is the weak structure. To improve mechanical characteristics of PLA foams, different polymer composites of PLA and Polyhydroxyalkanoate (PHA) were foamed and characterized in terms of acoustic performance, mechanical properties and foam morphology. Polymers used in this study are bio-based which is of great importance considering huge amount of foams used as acoustic absorbers in various industries.

scholarly journals Macroscopic modeling of open cell foams

PAMM ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Stephan Kirchhof ◽  
Alfons Ams
Keyword(s):  
Open Cell ◽  
Macroscopic Modeling ◽  
Open Cell Foams

Geometry Dependent Effective Elastic Properties of Open-Cell Foams Based on Kelvin Cell Models**

2013 ◽  
Vol 15 (12) ◽  
pp. 1292-1298 ◽  
Author(s):  
Johannes Storm ◽  
Martin Abendroth ◽  
Dongshuang Zhang ◽  
Meinhard Kuna
Keyword(s):  
Elastic Properties ◽  
Cell Models ◽  
Open Cell ◽  
Effective Elastic Properties ◽  
Open Cell Foams

Porous Bioceramics (Open Cell Foams) Expanded in Vacuum

2006 ◽  
Vol 309-311 ◽  
pp. 1023-1026
Author(s):  
E.T. Uzumaki ◽  
C.S. Lambert
Keyword(s):  
Zirconium Oxide ◽  
Cell Structure ◽  
The Body ◽  
Carbon Coatings ◽  
Open Cell ◽  
Glass Foam ◽  
Open Cell Foams ◽  
Titanium Foam ◽  
Porous Bioceramics ◽  
Scanning Electron

In this study, porous bioceramics (titanium foam with diamond-like carbon coatings, glass foam and zirconium oxide foam) were produced using expansion in vacuum. The porosity, the pore size and pore morphology can be adjusted in agreement with the application. The different 3D structures were obtained by varying the parameters of the process. The microstructure and morphology of the porous materials were observed by scanning electron microscopy (SEM) and optical microscopy. The foam exhibit an open-cell structure with interconnected macropores, which provide the potential for tissue ingrowths and the transport of the body fluids.

Sign in / Sign up

Export Citation Format

Share Document