Using Sensitivities for Flow Analysis
The capabilities of the sensitivity-equation method are presented in context of aerodynamic analysis of hypersonic flight and air-breathing propulsion systems. The method yields stability derivatives, provides parametric guidance, accurately predicts boundary-layer thinning and growth, the onset of flow separation, separation bubbles, and the driving mechanisms in chemically reacting flows. The accuracy of sensitivity-equation calculations are assessed for viscous, chemically reacting flows with comparisons to theoretical and central-difference results. The sensitivity results are used to prioritize design variables by level of relative influence. Being linear, the sensitivity solutions require 10% or less of the computational effort needed to compute flow solutions.
KeywordsEquivalence Ratio Flame Front Separation Bubble Sensitivity Equation Airfoil Surface
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