boundary-layer-separationlisted

# Boundary Layer Separation (aerodynamics/boundary-layer/boundary-layer-separation) Use when you must predict the boundary layer separation location on a two-dimensional body from its edge-velocity or pressure distribution. This leaf grows the laminar layer with the Thwaites integral relation along the edge-velocity traverse and flags the first station where the Thwaites lambda parameter crosses -0.09, the classical laminar separation criterion, and evaluates the Stratford-style pressure recovery criterion to estimate the turbulent separation station and the margin below the 0.35 threshold. Pure Python, stdlib only. It pairs with boundary-layer/boundary-layer-transition, whose Thwaites traverse ends at the natural-transition onset estimated by the Michel rule rather than running to separation, and with boundary-layer/boundary-layer-theory for flat-plate thickness and skin-friction context on the attached side of the flow. ## Domain quick reference - Thwaites integral for the momentum thickness on the laminar side: theta^2 = 0.45 * nu / U^6 * integral_0^x U^5 dx, integrated by the trapezoid rule over the edge-velocity stations (THWAITES_C = 0.45). The traverse starts with theta = 0 at the first station with U > 0; a stagnation head with U = 0 is skipped, which removes the U^6 singularity at the stagnation point. - Thwaites pressure-gradient parameter: lambda = theta^2 / nu * dU/dx, with dU/dx by central differences (forward at the first station, backward at th