Uncertainty Analysis of Supersonic Biplane's Aerodynamic Characteristics

摘要

Utilizing the interference of shock and expansion waves, supersonic biplane can reduce the wave drag remarkably. However, the supersonic biplane is only designed at special conditions, so that it has poor performance at off-design conditions. To analyze supersonic biplane's aerodynamic characteristics at off-design conditions, the non-instructive probabilistic collocation method has been employed to achieve uncertainty quantification. Besides, Sobol global sensitivity is adopted to accurately evaluate the influence of the input uncertainty parameters. The uncertainty parameters are Mach number and the angle of attack which both satisfy special normal distributions. Aerodynamic coefficients and pressure distribution from the biplane's surface as well as flow filed are studied. The results of uncertainty quantification show that the main reason for aerodynamic characteristics fluctuations is the pressure pulsation from the maximum thickness of the lower airfoil's upper surface. The results of global sensitivity show that Mach number is the most important factor for the variation of aerodynamic performance.