Abstract

trigger aerodynamic instability. Although instability has been reported in wind tunnel experiments and flight tests, the detailed mechanism of this possible instability has not been clarified. Therefore, it is necessary to elucidate the detailed instability mechanism by numerical analysis, as it cannot be realized experimentally. In addition, it is necessary to introduce fluid-structure interaction (FSI) analysis for flexible structures using a coupled method. The precise code interaction coupling environment (preCICE) coupling library is a powerful tool for the coupling analysis of fluid and structure solvers. 
To evaluate the effect of coupling two physical fields, the analyses of the fluid and structure were conducted separately. The results of the analysis verified that the wing deformed under a fluid force, which indicates the effectiveness of the FSI analysis model developed. A comparison with the single-field analysis demonstrated that the structure-derived frequencies in the FSI analysis appeared in the wing surface deformation and aerodynamic forces. However, the aerodynamic
coefficients obtained by the FSI analysis converged to the same values as those obtained by the single fluid analysis, thus indicating that from a macroscopic perspective, structural deformation negligibly influences aerodynamic forces. Therefore, it is necessary to analyze a shape that is closer to the actual machine.

Abstract

Many multiscale simulation problems require a many-to-one coupling between different scales. For such coupled problems, researchers oftentimes focus on the coupling methodology, but largely ignore software engineering and high-performance computing aspects. This can lead to inefficient use of hardware resources, on the one hand, but also inefficient use of human resources as solutions to typical technical coupling problems are constantly reinvented. This work proposes a flexible and application-agnostic software framework to couple independent simulation codes in a many-to-one fashion. To this end, we introduce a prototype of a new lightweight software component called Micro Manager, which allows us to reuse the coupling library preCICE for two-scale coupled problems. We demonstrate the applicability of the framework by a two-scale coupled heat conduction problem.

Abstract

Abstract

In the industrial design of turbomachinery blades their aeroelastic behaviour is most commonly investigated by methods, that use linearization or rely on unidirectional coupling. To circumvent the limitations of those methods a new fully coupled simulation in the time domain with the structural solver CalculiX and the turbomachinery CFD solver TRACE is currently developed and presented in this paper. The coupling library preCICE is chosen to couple the mentioned elaborated single physics solvers due to its focus on high performance computing applications. Within this work the preCICE adapter for CalculiX has recently been enabled to work with a special CalculiX method, that allows to investigate dedicated eigenforms of the blades or other structural objects. It is furthermore shown that the use of this CalculiX method can lead to a massive speedup for use cases, where the structural dynamics response can be well described by a piece-wise linear approximation within each increment. On the other hand a completely new preCICE adapter for TRACE has been developed and is introduced here. The preCICE-coupled system of CalculiX and TRACE is successfully validated against a TRACE-internal coupling approach by investigating a simple testcase with a NACA profile blade that shows good agreement.