Natural convection and heat transfer on a section-triangular roof

Natural convection and heat transfer on a section-triangular roof are common around buildings. In this study, the slope flow and the plume on the suddenly heated section-triangular roof are investigated using scaling analysis and numerical simulation. The dynamics and heat transfer are discussed. It has been demonstrated that there exist different regimes of transient natural convection on the roof, which depends on the Rayleigh number, the aspect ratio of the roof and the Prandtl number. The scaling laws in different scenarios including inertial and viscous regimes are obtained and verified by numerical results. There is agreement between the scaling laws and numerical results. Further, the formulae of heat transfer and natural convection on the roof are presented.