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Published on: February 22, 2018
Skin friction in zero-pressure-gradient boundary layers
1Department of Mechanical Engineering, Boston University, Boston, Massachusetts 02215, USA. vy@bu.edu
Abstract:
A global approach leading to a self-consistent solution to the Navier-Stokes-Prandtl equations for zero-pressure-gradient boundary layers is presented. It is shown that as Re(δ)→ ∞, the dynamically defined boundary layer thickness δ(x) ∝ x/ln2 Rex and the skin friction λ = 2τ(w)/ρU(0)(2) ∝ 1/ln2 δ(x). Here τ(w) and U0 are the wall shear stress and free stream velocity, respectively. The theory is formulated as an expansion in powers of a small dimensionless parameter dδ(x)/dx → 0 in the limit x → ∞.
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