Characterization of strain-induced damage in composites based on the dissipated energy density part I. Basic scheme and formulation

Latent heat storage units for refrigeration processes are promising as alternatives to water/glycol-based storage due to their significantly higher energy densities, which would lead to more compact and potentially more cost-effective storages. In this study, important thermophysical properties of five phase change material (PCM) candidates are determined in the temperature range between −22 and −35 °C and their compatibility with relevant metals and polymers is investigated. The goal is to complement existing scattered information in literature and to apply a consistent testing methodology to all PCMs, to enable a more reliable comparison between them. More specifically, the enthalpy of fusion, melting point, density, compatibility with aluminum, copper, polyethylene (PE), polypropylene (PP), neoprene and butyl rubber, are experimentally determined for 1-heptanol, n-decane, propionic acid, NaCl/water mixtures, and Al(NO3)3/water mixtures. The results of the investigations reveal individual strengths and weaknesses of the five candidates. Further, 23.3 wt.% NaCl in water stands out for its very high volumetric energy density and n-decane follows with a lower energy density but better compatibility with surrounding materials and supercooling performance. The importance of using consistent methodologies to determine thermophysical properties when the goal is to compare PCM performance is highlighted.

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A possible way to experimentally examine validity of the expressions of dissipated energy density

Optik ◽

10.1016/j.ijleo.2020.165756 ◽

2021 ◽

pp. 165756

Author(s):

Jiangwei Chen ◽

Yuyao Dai ◽

Yu Xuanyuan

Keyword(s):

Energy Density ◽

Dissipated Energy

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Characterization of Advanced High-Energy Density Li-S Batteries by FE-AEM, SEM/EDS X-ray Spectral Imaging and Feature Sizing/Chemical Typing Techniques

Microscopy and Microanalysis ◽

10.1017/s143192760909504x ◽

2009 ◽

Vol 15 (S2) ◽

pp. 1398-1399 ◽

Cited By ~ 5

Author(s):

VP Oleshko ◽

C Scordilis-Kelley ◽

A Xiao ◽

J Affinito ◽

Y Talyossef ◽

...

Keyword(s):

Energy Density ◽

Spectral Imaging ◽

High Energy ◽

High Energy Density ◽

X Ray

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009

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Explicit Q expressions for inhomogeneous P- and SV-waves in isotropic viscoelastic media

Journal of Geophysics and Engineering ◽

10.1093/jge/gxz106 ◽

2019 ◽

Vol 17 (2) ◽

pp. 300-312 ◽

Cited By ~ 3

Author(s):

Xu Liu ◽

Stewart Greenhalgh ◽

Bing Zhou ◽

Huijian Li

Keyword(s):

Energy Density ◽

Dissipation Factor ◽

Energy Balance Equation ◽

Dissipated Energy ◽

P Waves ◽

S Waves ◽

Viscoelastic Media ◽

Inhomogeneous Waves ◽

Inhomogeneity Parameter ◽

P And Sv Waves

Abstract We derive explicit expressions for the dissipation factors of inhomogeneous P and SV-waves in isotropic viscoelastic media. The Q−1 values are given as concise and simple functions of material parameters and the wave inhomogeneity parameter using two different definitions. Unlike homogenous waves, inhomogeneous waves may have significant differences in the values of dissipation factors because of different definitions. For example, under one of the three dissipation factor definitions that Q−1 is equal to the time-averaged dissipated-energy density divided by twice the time-averaged strain-energy density, it is found and proved that the dissipation factor of SV-waves is totally independent of the inhomogeneity parameter. For materials in which P-waves are normally more dissipative than S-waves (e.g. a porous reservoir), the dissipation factors of P-waves tend to decrease with increasing degree of inhomogeneity. Based on Buchan's classic real value energy balance equation, a parallel investigation is conducted for each step similar to that based on the Carcione equations, including derivation of explicit formulas (with inhomogeneity angle representing the degree of inhomogeneity of a plane wave), and dissipation curves calculations. We also obtain an inhomogeneity independent formula of $Q_{\, SV}^{ - 1}$, and exactly the same phase velocity and attenuation dispersion results for the example material.

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