Applications Of Optimization Methods To Conceptual Design Of Civil Jets

Currently, china is dependently developing large commercial jets. The technology of conceptualdesign for large commercial jets is increasingly drawing attention. Application of optimization methodto the conceptual design of large commercial jets can substantially enhance the design efficiency. Thisthesis studies two design optimization problems in the conceptual design of large commercial jets byuse of the API (Application Programming Interface) technique of optimization software iSIGHT.The main contributions of this thesis are summarized as the follows:1) The API (Application Programming Interface) technique of optimization software iSIGHT isdiscussed based on understanding the functions and structure of the software iSIGHT. A procedure forthe API technique of iSIGHT is presented, which provide an effective way for customizing a specificoptimization tool or computing environment.2) A parametric design method for cross-section shape of fuselage for commercial transports ispresented. A computer program, as a design tool, is developed to rapidly generate the optimalcross-section shape of fuselage by using VBA as API of CAD software AutoCAD and optimizationsoftware iSIGHT, which provide an effective tool for cabin layout of commercial jets.3) A computing framework optimization for conceptual design of civil jets is developed by usingthe API technique of iSIGHT to integrate legacy code-the comprehensive analysis program for thecommercial jets, which provide an effective computing environment for the conceptual design ofcommercial jets.4) Aiming at the conceptual design of the wide-body airliner, two conceptual designs for theshort/medium range wide-body airliner and long range wide-body airliner are completed by use of thecomputing framework optimization for conceptual design of civil jets. The size of wing andempennage, weight, fuel consumption and direct operating costs of the two airliners are compared.The results indicate that the wing area, engine thrust required and operating empty weight of theshort/medium range airliner are much lower than those of the long range airliner. When the blockrange is1200km, the fuel consumption of the short/medium range airliner is about72%of that of thelong range airliner. When the block range is4500km, the fuel consumption of the short/medium rangeairliner is about62%of that of the long range airliner.