Find in Library

The general aviation airplane is an important component part of civil airplanes,and its shape feature is of important influence on aircraft drag.The numerical simulation method based on Navier-Stokes equation is utilized to analyze the barrel shape feature of drag polar curve of classical general aviation airplane,and the influence of upper surface outline curvature of fuselage.The aerodynamic characteristics difference for a typical general aviation airplane under three different rear fuselage contractions are studied,including upper surface,lower and side ones.The aerodynamic characteristics of basic shape and improvement shape are compared.The results show that,with the increase of contraction rate,the pressure drag and frictional drag for lower surface and side surface are decreased,while for the upper surface,the pressure drag is increased.The suitable fuselage contraction can reduce the pressure drag of 29.76%,and increase the maximum lift-to-drag of the fuselage of 6.34%.The reasonable contraction pattern can not only increase the lift-drag ratio,but improve the longitudinal static stability as well.