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transonic-similaritylisted

Use when you must apply compressibility corrections to subsonic aerodynamic coefficients: compute the Prandtl-Glauert factor and the refined Karman-Tsien correction for the pressure coefficient at a given Mach number, evaluate the transonic similarity parameter linking thickness and sweep effects, and estimate the critical Mach number at which local flow first reaches sonic speed. Produces corrected pressure coefficients and corrected lift slope, the critical Mach estimate, and drag-divergence Mach guidance for airfoil selection and high-subsonic wing design. Trigger: compressibility correction, Prandtl-Glauert, Karman-Tsien, transonic similarity, critical Mach number, pressure coefficient.
ashfordeOU/aero-agent-skills · ★ 0 · AI & Automation · score 78
Install: claude install-skill ashfordeOU/aero-agent-skills
# Transonic Similarity Corrections (aerodynamics/high-speed/transonic-similarity) Use when the task is compressibility corrections for high-subsonic flows: the Prandtl-Glauert and Karman-Tsien pressure coefficient corrections, the transonic similarity parameter, and critical Mach estimation. ## Domain quick reference - Prandtl-Glauert (linearized thin-airfoil theory, valid below M ~ 0.7): perturbation quantities scale with the factor 1 / sqrt(1 - M^2). Pressure coefficient C_p = C_p0 / sqrt(1 - M^2), lift coefficient C_L = C_L0 / sqrt(1 - M^2), and section lift-curve slope a = a0 / sqrt(1 - M^2), where subscript 0 marks the incompressible value. - Karman-Tsien (extended, usable toward M ~ 0.85): C_p = C_p0 / (sqrt(1 - M^2) + (M^2 / (1 + sqrt(1 - M^2))) * C_p0 / 2). The denominator shrinks less than the Prandtl-Glauert factor alone, so the correction stays finite closer to M = 1. - Transonic similarity parameter: K = (1 - M^2) / tau^(2/3), with tau the thickness ratio (sweep enters through the effective Mach M * cos(Lambda)). Two thin configurations with equal K have similar pressure fields near M = 1. - Critical pressure coefficient (isentropic sonic limit at freestream Mach M, gamma = 1.4 default): C_p* = (2 / (gamma * M^2)) * (((1 + (gamma - 1) / 2 * M^2) / (1 + (gamma - 1) / 2))^(gamma / (gamma - 1)) - 1). Local flow is sonic where C_p equals C_p*. - Critical Mach number M_cr: solve C_p0 / sqrt(1 - M^2) = C_p*(M) for the smallest M; the p