boundary-layer-transitionlisted

# Boundary Layer Transition (aerodynamics/boundary-layer/boundary-layer-transition) Use when you must predict where the laminar boundary layer turns turbulent on a two-dimensional body from its edge-velocity distribution. This leaf implements the standard integral estimate: grow the laminar layer with the Thwaites relation to get the momentum thickness theta at each station, then apply the Michel empirical criterion on the local Reynolds numbers to locate the natural transition point. The logic is pure Python, stdlib only, and covers a clean two-dimensional surface (no roughness, sweep or suction inputs and no Tollmien-Schlichting wave-growth integration; the Michel criterion replaces an eN envelope). It pairs with aerodynamics/boundary-layer/boundary-layer-theory, which owns the flat-plate thickness and skin-friction correlations on either side of the transition. ## Domain quick reference - Edge-velocity Reynolds number: Re_x = Ue(x) * x / nu with Ue the inviscid edge velocity and nu the kinematic viscosity (SI units throughout, m, m/s, m2/s). - Thwaites integral relation for the laminar momentum thickness: theta(x)^2 = THWAITES_C * nu / Ue(x)^6 * integral_0^x Ue(xi)^5 d(xi) with THWAITES_C = 0.45. The integral is evaluated cumulatively with the trapezoid rule over the supplied stations; the segment from the leading edge (x = 0) to the first station keeps Ue at its first-station value, which makes the constant-velocity flat plate exact. - Momentum-th