The UK Turbulence Consortium
Lead Research Organisation:
Imperial College London
Department Name: Aeronautics
Abstract
Understanding, predicting and controlling turbulent flows is of central importance and a limiting factor to a vast range of industries: naval, aeronautical, automotive, power generation, process, pharmaceutical, meteorological and environmental. Many of the environmental and energy-related issues we face today cannot possibly be tackled without a better understanding of turbulent flows. The UK Turbulence Consortium (UKTC) is a group of UK researchers committed to undertaking high quality, world leading turbulence simulation and scientific research using high performance computing systems. Funded in 1995, the UKTC has been through six highly successful iterations, with significant growth, from 5 original members to 70 members from nearly 30 UK institutions for the present bid, with an inclusive approach to developing and serving the community. Our view is that the key to advances in turbulence is by sustaining and stimulating interaction among researchers. It is essential that a diverse range of viewpoints, opinions, strategies and methods are brought together in an efficient and constructive manner. The essence of the UK Turbulence Consortium is to provide the central core of a needed critical mass activity considering the big challenges posed by turbulence.
In the last 25 years, the UKTC has (i) demonstrated its ability to convert access to national High-End Computing (HEC) resources into internationally leading research, (ii) established its international competitiveness, (iii) helped its members to leverage and secure multi-million pound grants from governmental funding bodies and industries, (iv) allowed the discovery of new fluid flow phenomena which have led to new ways of improving beneficial effects and reducing negative effects of turbulent flows and (v) facilitated the design of more sophisticated turbulence models redefining industry standards.
In the last 25 years, the UKTC has (i) demonstrated its ability to convert access to national High-End Computing (HEC) resources into internationally leading research, (ii) established its international competitiveness, (iii) helped its members to leverage and secure multi-million pound grants from governmental funding bodies and industries, (iv) allowed the discovery of new fluid flow phenomena which have led to new ways of improving beneficial effects and reducing negative effects of turbulent flows and (v) facilitated the design of more sophisticated turbulence models redefining industry standards.
Organisations
Publications
Bempedelis N
(2023)
Turbulent entrainment in finite-length wind farms
in Journal of Fluid Mechanics
Bilbao-Ludena J
(2023)
Structure of vorticity and turbulence fields in a separated flow around a finite wing: Analysis using direct numerical simulation
in Physical Review Fluids
Cartland-Glover G
(2024)
Direct and Large Eddy Simulation XIII - Proceedings of DLES13
Chen X
(2023)
Backflow structures in turbulent pipe flows at low to moderate Reynolds numbers
in Journal of Fluid Mechanics
Fang J
(2023)
Direct numerical simulation of supersonic internal flow in a model scramjet combustor under a non-reactive condition
in Physics of Fluids
Gao A
(2023)
Three-dimensional transition and force characteristics of low-Reynolds-number flows past a plunging airfoil
in Journal of Fluid Mechanics
Gori F
(2023)
Sensitivity analysis of wake steering optimisation for wind farm power maximisation
in Wind Energy Science
Hamzehloo A
(2023)
Direct numerical simulations and spectral proper orthogonal decomposition analysis of shocklet-containing turbulent channel counter-flows
in International Journal of Heat and Fluid Flow
| Title | 2DECOMP&FFT |
| Description | The 2DECOMP&FFT library is a software framework written in modern Fortran to build large scale parallel applications. It is designed for applications using three-dimensional structured meshes with a particular focus on spatially implicit numerical algorithms. However, the library can be easily used with other discretisation schemes based on a structured layout and where pencil decomposition can apply. It is based on a general-purpose 2D pencil decomposition for data distribution and data Input Output (I/O). A 1D slab decomposition is also available as a special case of the 2D pencil decomposition. The library includes a highly scalable and efficient interface to perform three-dimensional Fast Fourier Transforms (FFTs). The library has been designed to be user-friendly, with a clean application programming interface hiding most communication details from application developers, and portable with support for modern CPUs and NVIDIA GPUs (support for AMD and Intel GPUs to follow). |
| Type Of Technology | Software |
| Year Produced | 2023 |
| Open Source License? | Yes |
| Impact | Possibility to use GPU hardware |
| URL | https://www.theoj.org/joss-papers/joss.05813/10.21105.joss.05813.pdf |
| Title | Code_Saturne |
| Description | Code_Saturne is a multi-physics CFD open source software first developed by industry, and now widely spread in academia. It relies on the finite-volume method to discretise the equations up to 2nd order in space and time, and is suitable for LES in complex geometries, as its unstructured nature support sany type of cells. It is written in C, Fortran and Python is used to manage the simulations. MPI/OpenMP handle parallelisation, and the code has shown good performance on over 3 million threads on Argonne's Blue Gene/Q. |
| Type Of Technology | Software |
| Year Produced | 2019 |
| Open Source License? | Yes |
| Impact | See list of publications |
| URL | https://www.code-saturne.org |
| Title | Nektar++ |
| Description | Nektar++ is a tensor product based finite element package designed to allow one to construct efficient classical low polynomial order h-type solvers (where h is the size of the finite element) as well as higher p-order piecewise polynomial order solvers. Nektar++ is available in both a source-code distribution and as pre-compiled binary packages for a number of operating systems. |
| Type Of Technology | Software |
| Year Produced | 2019 |
| Open Source License? | Yes |
| Impact | See list of publications |
| URL | https://www.nektar.info/ |
| Title | Xcompact3d |
| Description | Xcompact3d is a Fortran-based framework of high-order finite-difference flow solvers dedicated to the study of turbulent flows. Dedicated to Direct and Large Eddy Simulations (DNS/LES) for which the largest turbulent scales are simulated, it can combine the versatility of industrial codes with the accuracy of spectral codes. Its user-friendliness, simplicity, versatility, accuracy, scalability, portability and efficiency makes it an attractive tool for the Computational Fluid Dynamics community. XCompact3d is currently able to solve the incompressible and low-Mach number variable density Navier-Stokes equations using sixth-order compact finite-difference schemes with a spectral-like accuracy on a monobloc Cartesian mesh. It was initially designed in France in the mid-90's for serial processors and later converted to HPC systems. It can now be used efficiently on hundreds of thousands CPU cores to investigate turbulence and heat transfer problems thanks to the open-source library 2DECOMP&FFT (a Fortran-based 2D pencil decomposition framework to support building large-scale parallel applications on distributed memory systems using MPI; the library has a Fast Fourier Transform module). When dealing with incompressible flows, the fractional step method used to advance the simulation in time requires to solve a Poisson equation. This equation is fully solved in spectral space via the use of relevant 3D Fast Fourier transforms (FFTs), allowing the use of any kind of boundary conditions for the velocity field. Using the concept of the modified wavenumber (to allow for operations in the spectral space to have the same accuracy as if they were performed in the physical space), the divergence free condition is ensured up to machine accuracy. The pressure field is staggered from the velocity field by half a mesh to avoid spurious oscillations created by the implicit finite-difference schemes. The modelling of a fixed or moving solid body inside the computational domain is performed with a customised Immersed Boundary Method. It is based on a direct forcing term in the Navier-Stokes equations to ensure a no-slip boundary condition at the wall of the solid body while imposing non-zero velocities inside the solid body to avoid discontinuities on the velocity field. This customised IBM, fully compatible with the 2D domain decomposition and with a possible mesh refinement at the wall, is based on a 1D expansion of the velocity field from fluid regions into solid regions using Lagrange polynomials or spline reconstructions. In order to reach high velocities in a context of LES, it is possible to customise the coefficients of the second derivative schemes (used for the viscous term) to add extra numerical dissipation in the simulation as a substitute of the missing dissipation from the small turbulent scales that are not resolved. Xcompact3d is currently being used by many research groups worldwide to study gravity currents, wall-bounded turbulence, wake and jet flows, wind farms and active flow control solutions to mitigate turbulence. |
| Type Of Technology | Software |
| Year Produced | 2019 |
| Open Source License? | Yes |
| Impact | see list of publications |
| URL | http://www.incompact3d.com |
| Description | Training and hackathon activities |
| Form Of Engagement Activity | Participation in an activity, workshop or similar |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Postgraduate students |
| Results and Impact | various training sessions and hackathons were organised to show other scientists how to use our software |
| Year(s) Of Engagement Activity | 2023 |