4. Ordinary Differential Equations of Boundary Layer of Nanofluid’s Natural Convection

The partial differential equations of natural convection boundary layer with conventional fluid’s flow are equivalently transformed to the related ordinary differential equations. A feasibility is demonstrated to describe the mass, momentum and energy conservation of nanofluid’s natural convection by using those of nanofluid’s natural convection. By an innovative similarity transformation, the partial differential equations of nanofluid’s natural convection boundary layer are equivalently transformed to the related ordinary differential equations. On this basis, the two-dimensional ordinary differential equations of nanofluid’s natural convection are determined for extensive exploration of heat transfer of nanofluid’s natural convection.