Mixture theory

About: Mixture theory is a research topic. Over the lifetime, 616 publications have been published within this topic receiving 19350 citations.

Averaged equations for an isothermal, developing flow of a fluid- solid mixture

Abstract: A mathematical description of a flowing fluid with entrained particulate solids is presented within the context of Mixture Theory. The mixture is considered to consist of a linearly viscous fluid and a granular solid. The balance of mass and balance of linear momentum equations for each component are averaged over the cross section of the flow to obtain ordinary differential equations describing developing flow between parallel plates. The resulting coupled equations describe the variation of the average velocities and volume fraction in the direction of flow, and represent a simplified approximate set of equations which are easier to use in engineering applications.

Face recognition using probabilistic two-dimensional principal component analysis and its mixture model

Abstract: In this paper, by supposing a parametric Gaussian distribution over the image space (spanned by the row vectors of 2D image matrices) and a spherical Gaussian noise model for the image, we endow the two-dimensional principal component analysis (2DPCA) with a probabilistic framework called probabilistic 2DPCA (P2DPCA), which is robust to noise. Further, by using the probabilistic perspective of P2DPCA, we extend P2DPCA to a mixture of local P2DPCA models (MP2DPCA). MP2DPCA offers us a method of being able to model faces in unconstrained (complex) environment with possibly large variation. The model parameters could be fitted on the basis of maximum likelihood (ML) estimation via the expectation maximization (EM) algorithm. The experimental recognition results on UMIST face database confirm the effectivity of the proposed methods.

Steady flow of a fluid-solid mixture in a circular cylinder

Abstract: A mathematical description for a flowing mixture of solid particulates and a fluid similar to a coal-water slurry, is developed within the context of Mixture Theory. Specifically, the equations governing the flow of a two-component mixture of a Newtonian fluid and a granular solid are derived. These relatively general equations are then reduced to a system of coupled ordinary differential equations describing steady flow of the mixture through a pipe. The resulting boundary value problem is solved numerically and results are presented for cases in which drag and lift interactions are important. 44 refs.

A macro-microscopic coupled constitutive model for fluid-saturated porous media with compressible constituents.

Abstract: The paper provides a macro-microscopic coupled constitutive model for fluid-saturated porous media with respect to the compressibility of the solid skeleton, the real solid material and the fluid phase. The derivation of the model is carried out based on the theory of porous media and is consistent with the second law of thermodynamics. Unlike some traditional concepts, in the present paper, two different sets of independent variables are introduced to implement the coupled behavior between the compressibility of the solid skeleton and the real solid material. Altogether the proposed model exploits five independent variables, i.e. the deviatoric part of the right Cauchy-Green deformation tensor, the partial density of solid phase, the density of the real solid material, the density of the real fluid material and the relative velocity of the fluid phase. Subsequently, the linearized version of the proposed constitutive model is also presented and compared with some models by other authors. It is found that Biot's model can also be derived based on the proposed model, which indicates the present work bridges the gap between the theory of porous media and the theory used in the model by Biot.