AIRCRAFT LIFT AND MANEUVERABILITY ENHANCEMENT BY GENETIC GEOMETRY OPTIMIZATION OF LEX CONFIGURATION

To enhance the maneuverability of the selected aircraft model, a standard genetic algorithm （GA） is used as an optimization method for the preliminary design of the leading-edge extension （LEX） layout. The aerodynamic loads and the maximum lift coefficient of the complete aircraft configuration （fuselage＋wing＋tail） are computed by using the modified three-dimensional low-order panel method in conjunction with the semi-empirical formulas of DATCOM. Results show that the lift coefficient increases approximately 20.5%- 15.3% for Mach number 0. 4-0.8 and 6.8% for Mach number 1.2, and its maximum value approximately 9.5% -15.0% for Machnumber 0.2-0.95when LEXis installed. A 6.6%-8.0 % gain at altitudes of 1-5 km on the turn rate maneuverability and the corner speed have been achieved in the subsonic regime.

让心中生长一棵文学之树

可以这样说吧,当你打开这本《东方少年》杂志时,我们便在文学之路上相遇相识了。如果说,文学是棵参天大树的话,那诗歌、散文、小说、童话等等,就是各呈其姿、各显其色的枝、叶、花、果了。这棵大树是属于我们每个人的,我们每个人心中都可以生长着这样一棵大树。楼高凭基固,树茂缘根深。读书则是我们心中文学之树繁茂所凭借的长根细须。关于这一点,我该是有一点点的体会可以与大家分享的。