Non-Reflective Boundary Conditions for Computational Fluid Dynamics of External Flows

Lead Research Organisation: University of Southampton
Department Name: Faculty of Engineering & the Environment


Non-reflective boundary conditions are regularly used in numerical predictions of sound propagation to prevent spurious numerical reflections from the edges of the domain contaminating the results of interest.
Application to aerodynamic CFD, and to industrial standard RANS CFD codes in particular, has been patchy, with an emphasis on in-duct acoustic prediction.
Recent work in conjunction with Rolls-Royce suggests there may be a significant advantage in applying non-reflecting boundary conditions to external flow CFD calculations for both aerodynamic and acoustic applications.
The research envisaged will include the following:
1. Survey the range of non-reflecting boundary conditions used in CFD and acoustics codes.
2. Shortlist and test most promising candidates for aerodynamic CFD application, taking into account issues related to complex geometry and mesh, non-uniform mean flow and the presence (at domain exit) of vortical disturbances.
3. Propose, develop, implement and validate a new non-reflecting boundary condition in an industrial CFD code.
The primary application objective is the calculation of jet engine inlet and exhaust aerodynamic and aeroacoustic performance, though there may be opportunity later in the programme to consider other applications (such as Marine CFD). The project is supported by Rolls-Royce, who will provide guidance as to the industrial requirements and also provide support and advice on implementation.
KeyWords: Non-Reflective Boundary Conditions, Eigenmodes, Wave-Splitting, Perfectly Matched Layers, Sponge Layers, Infinite Elements, Calderon Projectors


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Studentship Projects

Project Reference Relationship Related To Start End Student Name
EP/N509747/1 01/10/2016 30/09/2021
1802007 Studentship EP/N509747/1 26/09/2016 30/09/2020 Kamran Zaabar
Description I have found a way to make computers run engineering simulations more efficiently when trying to simulate sound.
Exploitation Route Other engineers to reduce aeroplane noise
Sectors Aerospace, Defence and Marine