An experimental study of the effective thermal conductivity of a sheared suspension of rigid spheres

An experimental study was conducted to measure the effective thermal conductivity of a sheared suspension of rigid spherical particles. The objective was to verify the theoretical prediction of Leal (1973) for a dilute suspension undergoing shear at low particle Peclet number, and to extend the range of the experiments to conditions beyond the scope of the theory. Surprisingly, reasonable agreement with the theoretical prediction was observed even for suspensions of moderate concentrations (volume fraction ≤ 0.25) and higher Peclet numbers Pe 0(1)]. The trend of the data, however, verifies the obvious fact that the theory does not completely describe the transport behavior at higher concentrations and Peclet numbers. The range of quantitative applicability of Leal's result is apparently only for Pe < 0.01 and < 0.01, but the changes in the effective thermal conductivity in this domain were too small to be measured in our apparatus.