# The radiative heat transfer could be treated as

The radiative heat transfer could be treated as a Pepstatin A process by introducing the radiative conductivity in cellular porous materials and metallic foams [12], [30] and [31]:equation(6)qw″=−(kc+kr)∂T∂y=−k∂T∂ywhere kc, kr, and k are conductive (molecular), radiative, and the effective conductivities, respectively. kr is approximated by Ref. [12]:equation(7)kr=16σT33βRhere βR is the Rosseland mean extinction coefficient and σ is the Stefan–Boltzmann constant [34] and [35]. The effective conductivity is:equation(8)k=kc+16σT33βR

3. Analysis of the problem

Dimensionless form of the momentum Eq. (1) and the boundary conditions (4) are:equation(9)?2u?y2−s2u+1M=0equation(10)?u?y y=0=0,u(y=1)=0where y is meiosis the dimensionless axis perpendicular to the flow direction, u is the dimensionless velocity, M is the viscosity ratio, s is the porous medium shape parameter, and Da is the Darcy number [13] and [14]:equation(11)y=y∗H,u=μu∗GH2,M=μeffμ,Da=KH2equation(12)s=1DaM=?Da