Urban Fluid Dynamics – Thermally Driven Environmental Flows Entrainment Dynamics of Shear-Free Convective Boundary Layers Growing in Linearly and Discretely Stratified Fluids

Boundary layers driven by surface buoyant forcings are commonly observed in the environmental flows. An atmospheric example of such boundary layer is the so-called convective boundary layer (CBL), which is driven by buoyancy production at the heated underlying surface during the daytime conditions. The buoyancy is defined as b= g − ( ρ -ρ0 )/ρ0 , where ρ is the density of the fluid, ρ0 is the reference density, and g is the acceleration due to gravity. In atmospheric terms, the buoyancy can be approximately expressed as b=g( v θ 0 v θ )/ 0 v θ , where v θ is the virtual potential temperature.