RHEOLOGICAL PROPERTIES OF FLOWS OF A DENSE GAS AND LIQUIDS IN NARROW SLOT-LIKE PORESYu. K. Tovbin, L. K. Zhidkova, and E. E. Gvozdeva UDC 533.7+541:183 The concentration dependences of the coefficients of shear viscosity of molecules in a wide range of pore fillings (from a rarefied gas to a liquid state) for different potentials of molecule-surface interactions have been theoretically investigated with the use of the lattice-gas model allowing for the volume occupied by atoms and the interaction between the atoms in the quasichemical approximation. This model allows one to find the self-consistent equilibrium characteristics of a vapor-liquid system and the coefficients of shear viscosity of molecules with the use of a single set of energy parameters. Molecular interpretation of the coefficient of sliding friction of the fluid near the pore walls is discussed. State Scientific Center of the Russian Federation "L. Ya. Karpov Scientific-Research Physicochemical Institute", Moscow, Russia; email: email@example.com. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 3, pp. 124-130, May-June, 2003. Original article submitted September 6, 2002.