Topic
Volume fraction
About: Volume fraction is a research topic. Over the lifetime, 16312 publications have been published within this topic receiving 374181 citations.
Papers published on a yearly basis
Papers
More filters
••
TL;DR: In this article, the first and second laws for a flat plate minichannel-based solar collector where the working fluid is a suspension of boehmite alumina nanoparticles in a mixture of water and ethylene glycol were evaluated.
118 citations
••
TL;DR: In this article, the authors reported electrical conductivity and dielectric studies on the composites of conducting polyaniline (PANI) with crystalline semiconducting ZnS powder, wherein PANI has been taken as inclusion and Zn S as the host matrix.
Abstract: In the present paper, we report electrical conductivity and dielectric studies on the composites of conducting polyaniline (PANI) with crystalline semiconducting ZnS powder, wherein PANI has been taken as inclusion and ZnS crystallites as the host matrix. From the studies, it has been observed that the value of room temperature d.c. conductivity of the composites with volume fraction of PANI > 0.65 shows an unusual behaviour wherein, conductivity values of the composites exceed that of PANI itself with maximum value as high as 6 times that of PANI at the volume fraction of 0.85. A similar trend has also been observed for the real and imaginary parts of complex dielectric constant values of the composites. This unusual behaviour in the d.c. conductivity and dielectric properties has been attributed to the enhancement in the degree of crystallinity of PANI as a consequence of its interfacial interaction with ZnS matrix. The results of optical microscopy show coating of PANI all around the ZnS particles. The temperature dependent conductivity studies suggest the quasi one-dimensional VRH conduction in PANI as well as its composites with ZnS. FTIR and XRD studies have also been reported.
117 citations
••
TL;DR: In this paper, a nonlinear model for flocculated suspensions under the influence of an applied pressure is proposed, based on the assumption that when the volume fraction is high enough, the network formed from the aggregation of flocs possesses a compressive yield stress Py(φ) that is a function of local volume fraction φ only.
Abstract: Pressure filtration is an important method for removing liquids from a suspension. Previous work used linear models or applied to stable suspensions. Nonlinear models for flocculated suspensions are studied here. The equations governing the consolidation of flocculated suspensions under the influence of an applied pressure are based on the assumption that when the volume fraction is high enough, the network formed from the aggregation of flocs possesses a compressive yield stress Py(φ) that is a function of local volume fraction φ only. There are two modes of operation of the pressure filter—the fluid flux or the applied pressure is specified—and both of these are studied. The resulting nonlinear partial differential equations involve the time‐dependent piston position, and in the case of the suspension being initially unnetworked, another internal moving boundary below which the suspension is networked. The small time behavior of these systems is obtained with an asymptotic method. In general, at later times, the solution can only be found numerically and an algorithm for doing this is discussed. The important parameters and properties of the filter cake are described. The results suggest various ways of controlling the filtration process, which may be useful in the manufacture of ceramics.
117 citations
••
TL;DR: In this paper, the abrasive wear rates of composites of an Al-11.8Si-4Mg alloy containing up to 0.35 volume fraction of zircon particles (average size, 100 μm) were measured on an 80 grit aloxide cloth sheet.
117 citations
••
TL;DR: In this article, the low-shear viscosity of polyelectrolyte microgels is studied as a function of concentration, crosslink density and ionic strength.
Abstract: The low-shear viscosity of polyelectrolyte microgels is studied as a function of concentration, crosslink density and ionic strength. The variation of the viscosity with volume fraction is very similar to that found in hard-sphere colloidal suspensions. In salt-free dispersions, osmotic effects are responsible for the de-swelling of microgels at high polymer concentration. This softening effect modifies the viscosity near the overlap concentration.
117 citations