Determination of the rheological characteristics of dilute suspensions of deformable particles

Mathematical model of strain of droplets of a dispersed-phase polymer in flow of molten polymer blends

“…Its direction coincides with the vector of the axis of symmetry of an ellipsoid, and its modulus coincides with the length of the semiaxis of rotation a, i.e., n i  = a. The rheological equation describing the anisotropic fluid has the form [5] n . i = λ 1 n i + λ 2 d km n k n m n i + λ 3 d ij n j ,…”

“…The possibility of using the structural method in the rheology of dispersions is limited by their diversity and complex morphology. The structural-continuum method proposed in [5,6] combines the phenomenological (macroscopic) and structural (microscopic) approaches and enables one to allow for all the fundamental propositions of the continuum mechanics (continuity of the medium and discontinuity of functions characterizing its motion and state) and the distinctive features of the behavior of the dispersed phase. Thus, in the structural-continuum model, each point of the dispersion is characterized by the density, velocity, and pressure (just as in the classical mechanics) and by the so-called internal parameters, in addition.…”

“…The rheological state of the dispersion under study has been described by the equation obtained from the viewpoint of the structural-continuum approach for diluted suspensions with ellipsoidal deformable particles [5]. This equation contains one internal parameter -the vector n i related to the microstructural element -of a suspended deformable particle, depends on the character of flow of the medium, and may change in space and with time.…”