Session: 34-04 Computing architectures and solvers

Paper Number: 153604

Development of an Unstructured Multi-Stage Turbomachinery CFD Solver for Aerodynamic Investigations on Detailed Geometry 

During aerodynamic design in turbomachinery, detailed geometries in real machines are often neglected because of the restrictions in both CFD solvers and geometrical data handled in the workflow. The templated workflows based on structured grids are efficient and their data are easy to handle, but they are difficult to deal with irregular configurations. In order to gain capabilities of aerodynamic evaluations for irregular configurations like novel airframe-propulsion integrated systems or complex geometries of air-cooled turbines, we have developed a new unstructured CFD solver. The paper presents the design philosophy of the solver focusing on two key functions for industrial use: the multigrid acceleration and blade-row interfaces. The use of agglomeration multigrid accelerates steady simulations by 5 times without affecting converged solutions. The blade row interfaces are formulated to conserve mass flow rate, which can be applied regardless the domain decomposition for parallelization. For the mixing plane interface used in the steady flow simulations, it is shown that the use of exact area-averaging and the matching of flux across the interface are necessary for ensuring mass flow conservation across the interface. Also, a robust sliding interface for unsteady rotor-stator interaction simulation is newly developed for the new solver. The effects of implementation detail in the mixing plane interface are highlighted with simple test cases. For unsteady simulations, the effect of temporal convergence is investigated from both the time step size and residual reduction during internal iterations, using a practical high pressure compressor test case. Both the steady and unsteady results by the new solver are in line with other solvers, and the developed solver is now ready to be applied to various practical turbomachinery simulations.

Presenting Author: Atsushi Tateishi IHI Corporation

Presenting Author Biography: Atsushi Tateishi is a CFD and Aeromechanics engineer in IHI Corporation. He graduated the University of Tokyo in 2010 and received PhD degree in aerospace engineering from the same university in 2015. After experienceing postdoctoral researcher in the University of Tokyo, he joined IHI Corporation in 2019, and have been working on CFD and aeromechanics related topics with compornent development engineers. He is now responsible for the development of CFD and aeromechanics simulation tools for the aerodynamic design of aircraft engine compornents.

Authors:

Atsushi Tateishi IHI Corporation
Takashi Goto IHI Corporation
Naoki Tani IHI Corporation