Design optimization of a three-dimensional diffusing S-duct using a modified SST turbulent model

For many embedded engine systems, the intake duct geometry introduces flow distortion and unsteadiness, which must be understood when designing the turbomachinery components. The aim of this work i...

/pdf/complex-aeroengine-intake-ducts-and-dynamic-distortion-333z63j593.pdf

Complex Aeroengine Intake Ducts and Dynamic Distortion

Computational Fluid Dynamics (CFD) simulation results for flow in a diffusing, S-duct are presented in this paper. These results were generated for the first AIAA Propulsion Aerodynamics Workshop (PAW01) using different codes, grids, turbulence models, and computers. Examples of computational grids for unstructured and structured solvers were provided by the PAW01 committee to each participant. The geometry of the test case was also provided for those interested in developing their own grids. This paper summarizes the results from that first workshop and documents the effects of grid refinement, symmetry boundary conditions, turbulence models, and codes used by the various participants from across industry and academia. The CFD studies were performed as a blind trial and are compared with the available experimental data during the workshop and within this paper. The objective of the workshop was to provide an impartial forum to present the findings, discuss the results and evaluate the effectiveness of existing computer codes and modeling techniques.

A Comparison of Several CFD Codes with Experimental Data in a Diffusing S-Duct

The unsteady distorted flowfields generated within convoluted aeroengine intakes can compromise the engine performance and operability. Therefore, there is a need for a better understanding of the ...

/pdf/convoluted-intake-distortion-measurements-using-stereo-2a7agfqsyb.pdf

Convoluted Intake Distortion Measurements Using Stereo Particle Image Velocimetry

The focus of this paper is on the numerical simulation of compressible flow in diffusing S-ducts; this flow is characterized by secondary flow as well as regions of boundary-layer separation. The S-duct geometry produces streamline curvature and an adverse pressure gradient resulting in these flow characteristics. Two S-duct geometries are employed in this investigation: one was used in an experimental study conducted at NASA John H. Glenn Research Center at Lewis Field in the early 1990s, and the other is a benchmark configuration proposed by AIAA Propulsion Aerodynamics Workshop to assess the accuracy and best practices of computational fluid dynamics solvers. The computational fluid dynamics flow solver ANSYS-FLUENT is employed in the investigation of compressible turbulent flow through the S duct. A second-order accurate, steady, density-based solver is employed in a finite-volume framework. The three-dimensional Reynolds-averaged Navier–Stokes equations are solved on a structured mesh with a number o...

Simulation of Secondary and Separated Flow in Diffusing S Ducts

This paper focuses on the validation and application of a new one-equation eddy viscosity model derived from k-ω closure (the Wray–Agarwal model) for three-dimensional flows in serpentine diffusers (S ducts). The S-duct geometry produces streamline curvature and an adverse pressure gradient, resulting in flow separation. Two S-duct geometries are employed in this investigation: one was used in an experimental study conducted at NASA John H. Glenn Research Center in the early 1990s, and the other used in an experimental study conducted at ONERA–The French Aerospace Lab in 2006 and considered for computational fluid dynamics technology validation during the AIAA Propulsion Aerodynamics Workshops in 2012 and 2014. The computational fluid dynamics flow solver ANSYS Fluent is used for flow calculations. Results from the new “Wray–Agarwal” one-equation turbulence model, the widely used Spalart–Allmaras, and the shear-stress-transport k-ω models are compared to the available experimental data. Results obtained w...

Computation of Flow in S Ducts with Wray-Agarwal One-Equation Turbulence Model

The focus of this article is on the numerical simulation of compressible flow in a diffusing S-duct inlet; this flow is characterized by secondary flow as well as regions of boundary layer separati...

Colin Fiola

Papers

Simulation of Secondary and Separated Flow in Diffusing S Ducts

Computation of Flow in S Ducts with Wray-Agarwal One-Equation Turbulence Model

Simulation of secondary and separated flow in a diffusing S-duct using four different turbulence models

Simulation of Secondary and Separated Flow in a Diffusing S-Duct

Simulation of Secondary and Separated Flow in a Serpentine Diffuser (S-Duct) for Air Breathing Propulsion