Our research is mainly on aerospace simulation, with focused efforts on the design and development of object-oriented simulation frameworks, distributed heterogeneous computation systems, and the integration of computer-aided tools in the engineering design process. Currently we are studying the application of variable complexity analysis methodology to the simulation of a high-bypass turbofan engine. Variable complexity analysis (VCA), which is sometimes referred to as zooming, allows an engineer to vary the level of detail of analysis throughout an engine system based upon the physical processes being studied.
In our present research, funded in part by the Ultra Efficient Engine Technology (UEET) program at the NASA Glenn Research Center, we are collaborating with the University of Cincinnati to demonstrate VCA on the GE90-94B high-bypass engine. The simulation utilizes the Numerical Propulsion System Simulation (NPSS) thermodynamic cycle modeling system coupled to a high-fidelity full-engine model represented by a set of coupled 3D computational fluid dynamic (CFD) component models. Boundary conditions from the balanced, steady-state cycle model are used to define component boundary conditions in the full-engine model. Operating characteristics of the 3D component models are integrated into the cycle model via partial performance maps generated from the CFD flow solutions using one-dimensional meanline turbomachinery programs. By coupling the 0D and 3D models, we hope to speed-up convergence of the aerodynamic coupling between the individual CFD component models. In addition, this approach has the potential to demonstrate mechanical coupling by obtaining a power balance in the CFD model a requirement generally neglected in reported full engine simulations.