The present study explores the parametric investigation of a heat sink filled with composite pure phase change material (PCM), nanocomposite (NCPCM), metal-foam (MF) by employing numerical approach for effective passive thermal management electronics. combinations are varied filling PCM, NCPCM, MF+PCM and NCPCM+MF. Different parameters such as MF materials, porosities, pore densities (PPI-pores...

Flow through a saturated, granular, porous medium can lead to internal erosion, preferential flow enhancement, and the formation of channels within the bulk of the medium. We examine this phenomenon using a combination of experimental observations, continuum theory and numerical simulations in a minimal setting. Our experiments are carried out by forcing water through a Hele-Shaw cell packed wi...

We investigate the nature of randomness in disordered packings of frictional spheres. We calculate the entropy of 3D packings through the force and volume ensemble of jammed matter, a mesoscopic ensemble and numerical simulations using volume fluctuation analysis and graph theoretical methods. Equations of state are obtained relating entropy, volume fraction and compactivity characterizing the ...

Colloidal particles interacting via a long-range repulsion can, in contrast to hard-sphere systems, exhibit crystalline ordering at low volume fraction. Here we experimentally investigate the structure and properties of such "colloidal Wigner crystals." We find a body-centered-cubic crystalline phase at volume fractions of ϕ≳15%, which exhibits large fluctuations of individual particles from th...

Introduction: Densities and porosities of meteorites provide information about the physical properties of their parent bodies (asteroids). Recent studies report the densities and porosities of ~40 ordinary chondrite (OC) meteorites [1,2]. In this study, we present 42 additional measurements of OC densities and porosities, and provide a rigorous analysis of the errors in the method. Additionally...

The rheological data of weakly attractive colloidal particles are shown to exhibit a surprising scaling behavior as the particle volume fraction, straight phi, or the strength of the attractive interparticle interaction, U, are varied. There is a critical onset of a solid network as either straight phi or U increase above critical values. For all solidlike samples, both the frequency-dependent ...

We investigate the capture of particles in soft porous media. Liquid foam constitutes a model system for such a study, allowing the radii of passage in the pore space to be tuned over several orders of magnitude by adjusting the liquid volume fraction. We show how particle capture is determined by the coupling of interstitial liquid flow and network deformation, and present a simple model of th...

We numerically produce fully amorphous assemblies of frictionless spheres in three dimensions and study the jamming transition these packings undergo at large volume fractions. We specify four protocols yielding a critical value for the jamming volume fraction which is sharply defined in the limit of large system size, but is different for each protocol. Thus, we directly establish the existenc...

We study the effects of fluctuations on the mesoscopic length scale on systems with mesoscopic inhomogeneities. Equations for the correlation function and for the average volume fraction are derived in the self-consistent Gaussian approximation. The equations are further simplified by postulating the expression for the structure factor consistent with scattering experiments for self-assembling ...

In this paper, the initial susceptibility of e-Fe3N magnetic fluid at volume concentrations in the range F = 0.0 ~ 0.0446 are measured. Compared with the experimental initial susceptibility, the Langevin, Weiss and Onsager susceptibility were calculated using the data obtained from the low concentration e-Fe3N magnetic fluid samples. The viscosity of the e-Fe3N magnetic fluid at the same concen...