Nomenclature

	- mass fraction concentration [-]
	- mean skin friction coefficient over the turbulent area of [-]
	- mean drag resistance coefficient in the REV [-]
	- mean form resistance coefficient in the REV [-]
	- mean skin friction coefficient on the REV laminar region [-]
	- drag resistance coefficient upon single sphere [-]
	- specific heat [J/(kgK)]
	- interface differential area in porous medium [m2]
	- character pore size in the cross section [m]
	- molecular diffusion coefficient [m2/s]
	- capillary morphology characteristic pore diameter [m]
	- diameter [m] of i-th pore [m]
	- mean diameter of medium's pores [m]
	- particle diameter [m]
	-porous medium Euler number [-]
	-Fanning friction factor [-]
	-gravitational constant [m2/s]
	- pore scale microroughness layer thickness [m]
	- internal surface in the REV [m2]
	- permeability [m2]
	- turbulent diffusion coefficient [m2/s]
	- analytic longitudinal diffusion coefficient [m2/s]
	- absorption equilibrium constant [-]
	- turbulent eddy viscosity [m2/s]
	- porous medium general scale [m]
	- averaged porosity [-]
	- number of pores [-]
	- number of pores with diameter of type i [-]
	- pressure [Pa]
	- ={U}f Lpor/D , porous medium Peclet number [-]
	- particle radius Peclet number [-]
	- , Prandtl number [-]
	- ={U}f Lpor/, porous medium Reynolds number [-]
	- ={U}f dm / , mean Reynolds number based on mean pore diameter [-]
	- cross sectional flow area [m2]
	- source or sink in diffusion equation [s-1]
	- total cross sectional area available to flow [m2]
	- projected obstacle area on the cross perpendicular pore surface [m2]
	- specific surface of a porous medium [1/m]
	- = [1/m]
	- cross flow projected area of obstacles [m2]
	- time interval for averaging of turbulent variable [s]
	- velocity fluctuation [m/s]
	- dimensionless porous medium interstitial velocity [-]
	- characteristic velocity in porous medium, equals to laminar regime velocity in dh tube, [m/s]
	- square friction velocity at the upper boundary hr of averaged over surface [m2/s2]

Subscripts

Superscripts

	- value in fluid phase averaged over the REV
	- equilibrium values at the assigned surface
	- value in solid phase averaged over the REV
	- mean turbulent quantity
	- mean cross-section quantity in a pore
	- mean cross-section quantity in a pore

Greek letters

	- averaged mass transfer coefficient over [m/s]
	- heat transfer coefficient in control volume [W/(m2K)]
	- averaged heat transfer coefficient over [W/(m2K)]
	- mean heat transfer coefficient across the layer [W/(m2K)]
	- = , characteristic heat transfer coefficient in the layer [W/(m2K)]
	- volumetric thermal expansion coefficient [1/K]
	- smooth wall boundary layer thickness [m]
	- representative elementary volume (REV) [m3]
	- turbulence dissipation rate [m2/s3]
	- Darcy friction coefficient in tubes [-]
	- dynamic viscosity [kg/(m s)] or [Pa s]
	- kinematic viscosity [m2/s]
	- density [kg/m3]
	- turbulent dissipation rate coefficient exchange ratio [-]
	- porous medium turbulent kinetic energy coefficient exchange ratio [-]
	- conventional turbulent kinetic energy coefficient exchange ratio [-]
	- porous medium fluid non-local temperature turbulent coefficient exchange ratio [-]
	- turbulent friction stress tensor [kg/(m s2)]
	- wall shear stress [N/m2]
	- roughness element slope angle [°]
	- scalar field variable [-]