Heat conductivity of concentrated suspensions

Heat and mass transfer simulation for thin-film two-phase emulsion flow over heated surfaces

“…Then, introducing the dimensionless temperature --and assuming that the thermophysical properties of the phases but the viscosity of the mixture vary insignificantly with tem perature, we can write Eqs. (4) and (8) for the two phase emulsion as a whole in the following form: (10) where (11) The thermal conductivity of the mixture, λ, can be determined via formulas known from the literature [11][12][13][14][15]. The rheological state of the medium can be described using, e.g., the Ostwald-de Waele model.…”

“…The rheological state of the medium can be described using, e.g., the Ostwald-de Waele model. Here, the rheological equation = 2µ eff e ij can be rep resented as (12) ( ) …”

“…The quantities m and n in Eq. (12) are effective coefficients of the rheological equation of state of the heteroge neous medium and account for the presence of a dis persed phase. The effective viscosity μ eff depends strongly on the concentration of the dispersed phase (α 2 ) and on the nonlinearity coefficient for the contin uous phase (n).…”

“…The temperature dependence of the effective vis cosity of the mixture can be taken into account using various approximations, such as the polynomial approximation (14) The coefficient n depends weakly on temperature, so n(T) ≈ const; therefore, relationship (14) for the rheological law (12) can be rewritten as…”

“…, , x x θ ( ) 12 , h x ( ) 12 2 , i U x x ( ) 1,2 . i = The above problem subject to boundary conditions (27) is solved practically in the same way as for the pre ceding zones:…”