Multidisciplinary design and optimization of gas turbine engine low pressure turbine at preliminary design stage

The gas turbine engine has evolved rapidly during past decades to provide a reliable and efficient business solution for global transportation. The engine design process is clearly a large contributor to this evolution. This process is highly iterative, multidisciplinary and complex in nature. The success of an engine depends on a carefully balanced design that best exploits the interactions between numerous traditional engineering disciplines such as aerodynamics and structures as well as lifecycle analysis of cost, manufacturability, serviceability and supportability. To take into account all of these disciplines and optimization should be used. Currently most of present state-of-art numerical modelling methods, which are used mainly at detailed design stage, are unsuitable for this task due to very high computational time. The solution to this problem can be found in multidisciplinary design and optimization at preliminary design stage with use of simple 1-2D models. This paper presents current aero engine design process and indicates possibilities of future improvements by utilization of proposed methodology, which take into account aerodynamic, thermodynamic and structures (blade, fixing and disc) calculations, connected in one multidisciplinary model, which is suited for optimization. All disciplinary models are presented and described in this paper as well as connection between them, with study over design variable, goal function and constrains that should be used. Moreover, a strategy of optimization is proposed as well as methods for acceleration of optimization process by use of surrogate. The presentation of methodology is followed by example optimization of low-pressure aero engine turbine