Radar cross section characteristics of rotor based on computational electromagnetics method

By taking Maxwell's equations as the governing equations, and employing four-stage Runge-Kutta method for the temporal discretization and Steger-Warming flux splitting scheme for the spatial discretization, the MUSCL(monotonic upstream-centered scheme for conversation laws) scheme was used to calculate the flux, and a numerical methodology for simulating the RCS(radar cross section) of rotor based on finite volume time domain method was developed. The O-type body fitted and orthogonal grid around rotor was generated using algebraic method. It has been demonstrated that the method is effective to simulate the RCS of the rotor. Firstly, calculations on RCS of rotor and airfoils about the polarization, angle of incidence and size have been conducted emphatically. Secondly, the influences of RCS on geometries of rotor airfoil have been investigated. Finally, the stealth of rotor airfoil has been obtained through linear weighted sum method. The results show that the RCS envelop of the rotor is represented by a continuous and oscillating area of strong scattering. The maximum radar detection range of the three blades rotor is 82.2% of the two blades rotor, helpful to control the maximum scattering peak. In four important scattering angle domains, the maximum radar detection ranges of HH02 rotor airfoil are 105.1%, 99.4%, 86.6% and 83.5% of NACA0012 airfoil, respectively, and the radar stealth performance of HH02 rotor airfoil is the best.