Design Optimization Method For Modular Platform-Based Aircraft Family

The aircraft family is a set of aircraft that uses common subsystems or common components while meeting different performances or operational requirements. The strategy of sharing components or subsystems in aircraft family can efficiently shorten the design period for a series of aircraft, and reduce the cost of development, as well as significantly cut down the cost of service/maintenance. The aircraft family sharing common subsystems has been an important strategy for aircraft industry in reaching business success.The design method for aircraft family is different from the traditional design method for single aircraft, and multiple missions and requirements should be simultaneously considered in conceptual design phase of aircraft family. This difference leads to new issues for aircraft family design. The research work in this dissertation focuses on the design optimzation method for aircraft family. The marjor contributions of the dissertation are summarized as follows.1) The literatures related to the design of product family are reviewed. A two-level optimization method is proposed for product family design. To reduce the computing expense during optimization process, the surrogate models is used in the two-level optimization process. An example of truss family design is presented to validate the effectiveness of the two-level optimization method in sloving product family design problem.2) The concept and method of the product family are applied to aircraft design. The research issues for aircraft family design are identified, which include configuration design, optimization of primary parameters in conceptual design, aerodynamic design optimization, structural design optimization, and multidisciplinary design optimization for aircraft family.3) The two-level optimization method is applied to sovle the parameter selection problem in the conceptual design for aircraft family. A conceptual design problem of a passenger jet family is used as an example to test the two-level optimization method. The validations indicate that the two-level optimization method is able to find the the optimum parameters for the conceptual design of aircraft family. 4) The two-level optimization method based on the surrogate model is applied to aerodynamic design optimization of aircraft family. A regional aircraft family is used as an example to illustrate aerodynamic design optimization of aircraft family. The results show that the two-level optimization method based on the surrogate model is an efficient method for the aerodynamic design optimization of aircraft family.5) The two-level optimization method based on the surrogate model and Genetic Algorithms are applied to the structural optimization for aircraft family. The wing structural design of a regional aircraft family is used as an example to study the structural optimization for aircraft family. It is found that the two-level optimization method based on the surrogate model can solve the wing structural design optimization of aircraft family in a relatively effective way.6) Multidisciplinary design optimization of aircraft family is a more complex problem. Aimed at studying a method of aerodynamic-structural integrated design optimization for aircraft family, a wing aerodynamic-structural optimization problem of a regional aircraft family is used as an example to illustrate the problem formulation. A three-level optimization method of the wing aerodynamic-structural integrated design for the aircraft family is proposed based on the combination of the aerodynamic optimization method and the structural optimization method of aircraft family. The feasibility of this three-level optimization method is validated by the computational results.In this research, the concept and method of product family are firstly applied to the aircraft design in systematical way. A set of optimization methods for aircraft family are proposed and validated through the systematical studies including optimation of conceptual design, aerodynamic design optimization, structural design optimization and multidisciplinary design optimization for aircraft family.