Virtual Gas Turbine: Pre-Processing and Numerical Simulations

Abstract

The design process of a gas turbine engine involves interrelated multi-disciplinary and multi-fidelity designs of engine components. Traditional component-based design process is not always able to capture the complicated physical phenomenon caused by component interactions. It is likely that such interactions are not resolved until hardware is built and tests are conducted. Component interactions can be captured by assembling all these components into one computational model. Nowadays, numerical solvers are fairly easy to use and the most time-consuming (in terms of man-hours) step for large scale gas turbine simulations is the preprocessing process. In this paper, a method is proposed to reduce its time-cost and make large scale gas turbine numerical simulations affordable in the design process. The method is based on a novel featured-based in-house geometry database. It allows the meshing modules to not only extract geometrical shapes of a computational model and additional attributes attached to the geometrical shapes as well, such as rotational frames, boundary types, materials, etc. This will considerably reduce the time-cost in setting up the boundary conditions for the models in a correct and consistent manner. Furthermore, since all the geometrical modules access to the same geometrical database, geometrical consistency is satisfied implicitly. This will remove the time-consuming process of checking possible mismatching in geometrical models when many components are present. The capability of the proposed method is demonstrated by meshing the whole gas path of a modern three-shaft engine and the Reynold’s Averaged Navier-Stokes (RANS) simulation of the whole gas path.

Favre-Averaged Nonlinear Harmonic Method for Compressible Periodic Flows

“…The baseline solver is the in-house CFD solver AU3X [18,19]. AU3X is written in C++ and solves the URANS equations using a fully implicit cell-centered finite volume scheme on unstructured or structured meshes.…”

“…Steady and unsteady solutions are obtained via pseudotime marching and dual time stepping, respectively. The code finds its applications from intake-fan interactions [20,21] to massively parallel whole-engine-gas-path CFD simulations [19]. The code has recently been optimized on modern many-core architectures [22].…”

Efficient Approach for Simulating Aperiodic Flows due to Geometry Distortions

“…The proposed method has been implemented in the in-house CFD solver AU3X [18,19]. AU3X solves the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations implicitly on unstructured meshes using a cell-centered finite volume scheme.…”

Software Prefetching for Unstructured Mesh Applications

“…The test vehicle for this study is AU3X [9], [10], a cell-centred finite-volume code used for solving the unsteady Favre-averaged Navier Stokes equations on unstructured meshes in both time and frequency domains. The solver obtains steady solutions via pseudo-time marching and timeaccurate solutions by dual-time stepping.…”