Experimental method of determining parameters characterizing the microstructure of micropolar liquids

On hydrodynamic boundary conditions for microstructural fluids

“…If the boundary surface does not rotate, w coincides with the angular velocity of a fluid microelement relative to this boundary. In this case, in the laboratory system of coordinates the proper angular velocity of medium particles v will be only a fraction of w, and so the boundary condition may be formulated as (7).…”

“…We consider the boundary condition (5) to be physically the most general and correct. However, it makes it impossible to estimate fluid microstructure parameters using the methods given in [7] and [8], which were applied for different boundary conditions. Condiff and Dahler [4] suggested a kinematic boundary condition in which two limiting cases are considered, namely, "no spin" and "no antisymmetric stress" at the boundary.…”

“…The disadvantage of some conventional boundary conditions are analysed. The proposed boundary condition results in solutions which depend on the microstructure parameters obtained using methods described in [7] and [8]. The above boundary condition is applicable to various theories for internal microstructure fluids suggested in [1][2][3][4][5][6].…”

Micropolar flow in a porous channel with high mass transfer

“…In general, the parameters may depend on the concentration and shape of the microelements, and a determination of the parameter values is a difficult matter [5]. The experimental work of Migun and colleagues (see, for example, Migun [12], Kolpashchikov et al [9], Migoun & Prokhorenko [11]) suggests that N 1 = O(1) for water in capillary tubes, whereas N 2 and N 3 must be non-negative for micropolar fluids [4]. For comparison with existing studies, in this work we set s = 0 , N 1,2 = 1 , N 3 = 10 −1 and investigate solution behaviour as Re is varied.…”

Linear and non-linear analyses of convection in a micropolar fluid occupying a porous medium

“…The common comment in respect of micropolar uids was that there are no experiments whatsoever in which any of the material moduli could be measured. The work of Migoun [5] demonstrated an experimental method of determining parameters characterizing the microstructure of such uids and seems to have laid to rest many doubts on the theory.…”