Showing papers on "Volume fraction published in 1969"
TL;DR: In this paper, the effect of an external magnetic field on the viscosity of a dilute suspension of magnetized particles is calculated to first order in the volume fraction of solution occupied by the particles.
Abstract: The effect of an external magnetic field on the viscosity of a dilute suspension of magnetized particles is calculated to first order in the volume fraction of solution occupied by the particles. The steady‐state motion of the particles under the influence of the external field is derived through an unusual application of Stokes' theorem to the equations of motion.
131 citations
TL;DR: In this article, an analytical analysis of the laminar flow behavior of high-solids suspensions from the physical properties of the liquid and solid components is presented, which is applicable to the design of pipe lines.
Abstract: Equations were developed for evaluating the laminar flow behavior of high-solids suspensions from the physical properties of the liquid and solid components. A technique was developed for calculating suspension flow rates as a function of pressure drop. The technique is applicable to the design of pipe lines. Flow measurements were made in pipe-line viscometers of a unique design that minimized entrance and exit effects. Experimental flow data were obtained for suspensions consisting of nickel, alumina, copper, or glass solids in sodium, xylene, or glycerine vehicles with solids concentrations of 28 to 55 vol. %. The basis for the correlation of the data was an analytical investigation of the flow behavior that considered the particle-particle interaction that takes place in a settled suspension. The correlation equations fit all systems investigated. They take into account the effects of liquid viscosity, liquid and solid densities, particle size, size distribution, particle surface area, volume fraction of solids in the suspension, and volume fraction of solids at maximum settled conditions.
64 citations
TL;DR: In this paper, the temperature dependence of relative modulus observed in filled thermoset, thermoplastic, and polyelectrolyte salt matrices is explained on the basis of induced stresses produced by the differences in the thermal expansion coefficients of the constituent materials.
Abstract: The temperature dependence of relative modulus observed in filled thermoset, thermoplastic, and polyelectrolyte salt matrices is explained on the basis of induced stresses produced by the differences in the thermal expansion coefficients of the constituent materials. The analysis is based on the assumption that the modulus of the matrix in a filled polymer is less than that of the unfilled polymer. The temperature dependence of relative modulus is expressed as a function of the difference in thermal expansion coefficients, the volume fraction, the relative modulus in the unstressed state, and mechanical properties of the phases. Agreement is good between the analysis and experimental results for three systems: epoxy and glass, polyethylene and wollastonite, and a polyelectrolyte salt with mica and asbestos.
22 citations
TL;DR: In this paper, the elastic constants of a composite containing parallel cylin drical fibers are expressed as a series expansion in terms of the volume fraction, c, of the fibers, and the coefficients of c2 are e
Abstract: The five elastic constants of a composite containing parallel cylin drical fibers are expressed as a series expansion in terms of the volume fraction, c, of the fibers. The coefficients of c2 are e...
20 citations
TL;DR: In this article, the authors adapted a method of determining the foil thickness of alloys containing precipitates to the present problem of voids, and obtained reasonable values within the expected range for the thickness of the specimen foils investigated.
18 citations
01 Apr 1969
TL;DR: In this article, the formation factor,F, required for the determination of the surface conductance at a solid/liquid interface, has been measured in solutions of potassium chloride, sodium chloride and barium perchlorate, some measurements were made at different frequencies, and provided electrode polarization is eliminated the variation ofF with the volume fraction of the solid, ϱ, is in complete agreement with that predicted theoretically byMaxwell.
Abstract: The formation factor,F, required for the determination of the surface conductance at a solid/liquid interface, has been measured in solutions of potassium chloride, sodium chloride, sodium sulphate and barium perchlorate, some measurements were made at different frequencies. Provided electrode polarization is eliminated the variation ofF with the volume fraction of the solid, ϱ, is in complete agreement with that predicted theoretically byMaxwell. Further the F/ϱ relationship is independent of the nature of the suspending electrolyte and the frequency of measurement in the range 500 Hz to 1.5 MHz.
11 citations
TL;DR: In this article, the authors applied the theory of polymer flow to a definition of shift factors which reduce the widely different melt viscosity/shear rate diagrams of plasticized PVC compounds to well-defined master curves.
Abstract: Existing theory of polymer flow has been applied to a definition of shift factors which reduce the widely different melt viscosity/shear rate diagrams of plasticized PVC compounds to well-defined master curves. The master curves are temperature dependent and also define the flow properties of the unplasticized polymer on which a group of plasticized compounds is based. For given plasticizers, the value of the shift factor was found to depend on melt temperature and plasticizer volume fraction. Explicit relationships have been generated for three plasticizer systems; for these, melt viscosity/shear rate data can be precalculated over several decades of shear, and in the temperature range of 150–200°C. Absolute values of the shift factors depend on the type of plasticizer, and a correlation with polymer/diluent interaction parameters has been attempted. Initial results, valid only at high plasticizer volumes and near the reduced melt temperature of a polymer/plasticizer mixture, support the existence of such a correlation.
7 citations
TL;DR: In this paper, an analytical analysis was made of radial source flow of uniform-size liquid particles into vacuum, and it was shown that the flowfield is characterized by a rapid departure from initial dynamic and thermal equilibrium with the action of interphase mass, momentum, and energy transfer providing the "throat" through which supersonic flow is attained.
Abstract: An analytical investigation was made of stationary radial source flow of uniform-size liquid particles into vacuum. The equations describing this system constitute a sixth-order, nonlinear, two-point boundary-value problem with a parameter-depe ndent singularity located in the vicinity of unity Mach number. A numerical procedure for the integration of this system was devised by means of which it was possible to evaluate parametrically the effects on the flow structure of such variables as the initial particle size^ evaporation coefficient, drag coefficient, heat-transfer coefficient, initial particle volume fraction, injection velocity, and temperature. It is shown that the flowfield is characterized by a rapid departure from initial dynamic and thermal equilibrium with the action of interphase mass, momentum, and energy transfer providing the "throat" through which supersonic flow is attained. For the case of vanishingly small particle size, it is demonstrated that the original sixth-order boundary-value problem degenerates to a third-order initial value type. Moreover, for the resulting quasi-equilibrium flow, an exact analytic solution was obtained and the limiting speed (at infinity) established. Nomenclature ae — "equilibrium" sound speed a/ = "frozen" sound speed Cps = particle specific heat Cpv — vapor specific heat CD ~ drag coefficient fp = drag force per unit volume of particles h = specific enthalpy k = vapor thermal conductivity ]Vf = frozen Mach number Mp — "particle" Mach number (Nup~] = particle Nusselt number P = local pressure PO — vapor pressure qp = heat-transfer rate per unit volume of particles R = gas constant r = radial coordinate s = specific entropy T = temperature u = velocity w = mass rate evaporated per unit volume of particles a = particle volume fraction; particle volume/total volume (3 = particle liquid volume fraction; liquid particle vol
7 citations
01 Jan 1969
TL;DR: In this article, the effect of simple organic solvents of different molecular size, flexibility and polarity on the glasstransition temperature (Tg) of polyvinyl chloride has been studied.
Abstract: The effect of simple organic solvents of different molecular size, flexibility and polarity on the glasstransition temperature (Tg) of Polyvinyl Chloride has been studied. Tg values were determined by Differential Scanning Calorimetry. The variation of ΔTg with solvent volume fraction (vs) is expressed by the relation, 1/ΔTg=Const. (1/vs−1). At any solvent volume fraction, ΔTg generally decreases with increase in molecular size.
5 citations
TL;DR: In this paper, the birefringence of several biaxially oriented polypropylene films swollen with a number of fluids has been measured and found to exhibit a minimum when plotted against the fluid refractive index, as predicted by the theory of Wiener.
Abstract: The birefringence of several biaxially oriented polypropylene films swollen with a number of fluids has been measured and found to exhibit a minimum when plotted against the fluid refractive index, as predicted by the theory of Wiener. However, a discrepancy in the form birefringence behavior is observed when samples of different degrees of crystallinity but the same total birefringence are compared. These results are interpreted in terms of Bullough's theory and suggest that this discrepancy arises because of different morphologies. A refractometric technique was employed that makes possible the simultaneous determination of birefringence and the volume fraction of fluid.
3 citations
31 Oct 1969
TL;DR: In this paper, the effect of structure on the mechanism of zirconium oxidation was investigated and it was shown that there is a high volume fraction of short circuit diffusion paths in the oxide formed on Zr in the temperature range 500-1000°C.
Abstract: Experiments were performed to determine the effect of structure on the mechanism of zirconium oxidation. It is shown that there is a high volume fraction of short circuit diffusion paths in the oxide formed on Zr in the temperature range 500–1000°C. The results of tracer experiments are in agreement with a short circuit diffusion mechanism. The assumption of line diffusion is shown to imply intuitively reasonable values of both the grain boundary thickness and the ratio of the line diffusion coefficient to the coefficient for lattice diffusion.
TL;DR: In this article, a study on the dynamic mechanical behavior of 1a rubber-like material (Solithane 113) filled with finely divided aluminium spherical particles of prescribed volume concentrations at frequencies in the lower audio frequency range, and at several temperatures above and below room temperature.