Evaluation of effect of existence, height and position of canard on Airplane aerodynamic coefficients

In this investigation، a numerical method based on potential flow for aerodynamic analysis of different configurations in has been developed. At first، results of this method are validated with experimental data and then، Influence mach number، canard existence، position and height canard than main wing on aerodynamic coefficients has been studied. According to results، with increasing Mach number lift coefficient increases. also، canard existence cause improvement of lift coefficient but the tails by canard impact on the load distribution of main wing and cause reduction and heterogeneity of load distribution. If canard and main wing be not the same height، heterogeneity of load distribution is solved and likewise، advantage of reducing load on wing span is maintained. With reducing the load on the wing span pitching moment is reduced. Results related to canard position show that too low distance and great distance between canard and main wing is not desired. Existence a proper distance between canard and main wing increases effect of canard and improvement aerodynamic characteristics is more.