Success Story: Advanced scalable workflow of ray tracing kernel for radiative heat loads assessment
success story # highlights:
- Keywords:
- Connecting codes
- Digital twins
- Industry sector: Automotive, Energy
- Key codes used: L2G, OpenFOAM, Raysect
Benefits for further research:
- Integration of field line, thermal, and optical simulations enables reactor monitoring
- Reduction in computational overhead through automated workflow
- Capability for accurate temperature detection despite surface reflections
- Identification of hotspots before component damage occurs
Organisations & Codes Involved:
The LeCAD laboratory manages one of the few supercomputers in Slovenia, which it uses for engineering tasks. This has enabled LeCAD to enter several major international science and infrastructure programs related to supercomputing and the development of new high-performance scientific codes for simulations of complex physical processes, mostly related to nuclear fusion technilogy.
Codes involved: L2G, OpenFOAM and Raysect
Engineering Design and Digital Twin of the First Wall of a Tokamak Fusion Reactor
scientific challenge:
In the engineering design and digital twin of the first wall of a tokamak fusion reactor, one of the challenges is to address the physical phenomena (e.g. heat flux deposition, photonic movement, and heat transfer) with sufficient complexity to arrive at a digital solution that is comparable to an actual experiment. This complexity comes at the cost of time and memory heavy computation. It is thus important to optimise the CPU/GPU solver for the codes being used and to demonstrate their capability to run them at exa-scale level. EXCELLERAT provides access to HPC infrastructure and expertise to achieve this goal.
Solution:
As a solution to this challenge, three codes have been connected in a scalable workflow to calculate a synthetic camera signal that represents a digital twin of a real Infrared camera measurement. At the same time, heat fluxes and temperatures were calculated for the full wall of the Tokamak fusion reactor. Field-line tracing code takes as input the magnetic ripple field from the R-Z and R-phi coils of the reactor simulating the full 360 degrees. The magnetic field caused by the plasma itself is added to the simulation and the field lines are then derived from both magnetic components. Heat flux is then calculated based on the particles arriving along the field-lines at the wall of a reactor. The heat transfer equation is then solved providing temperature distribution for the given heat fluxes. Optical simulations are then performed taking into account the temperature of the reactor wall and plasma power to mimic the movement of photons based on the radiation from the wall and plasma. This results in a digital image comparable to an experimental image.
scientific impact of this result:
The workflow faces significant computational challenges in calculating temperatures on the wall during fusion operation. The workflow involves three complex calculations of field line tracing, thermal modelling, and optical simulations, which currently operate on a single node only. This single-node approach is severely limiting because the complex geometries involved in fusion simulations require massive computational resources that exceed what local machines can provide. The current setup struggles with managing large datasets across different simulation steps, requires manual intervention between steps, and lacks the ability to efficiently scale computational resources across distributed systems.
EXCELLERAT is transforming the workflow by integrating the HPC framework that enables execution of all three simulation steps in parallel without the need for user intervention. The project is implementing automated data management systems and optimizing code for exascale computing, focusing on the parallel processing for field line tracing and thermal modeling.
The workflow is also crucial for real-time monitoring applications of fusion reactors. This workflow will help to process complex light calculations and temperature distributions. With HPC resources and standardized data formats (HDF5/netCDF), the workflow for synthetic diagnostics could enhance the safety and efficiency of fusion reactor operations.
Potential EXCELLERAT Services:
1) This example could be used as a best practice case for potential users/designers of nuclear fusion reactors, operators, or engineers (for their own studies). It could also be applied by any sector that uses camera diagnostics (e.g. automotive).
2) A potential service would be to scale the application to different use cases such as automotive testing facilities or smart city building monitoring. The workflow could be adapted to simulate and monitor heat distribution in different engineering components, or to analyse thermal patterns in large building complexes using IR cameras.
3) The integrated workflow could be developed into a specialized consulting service for industries requiring high-fidelity digital twins of heat transfer. This would be particularly valuable for critical infrastructure where temperature monitoring through reflective surfaces is challenging, such as concentrated solar power plants or high-temperature chemical processing facilities.
unique value of each service:
1) Best Practice Case Study Service: Provides a validated framework for complex multi-physics simulations that combine thermal, optical, and magnetic field modelling with a high degree of accuracy. This service distinguishes itself by offering a complete end-to-end solution for real-time monitoring through reflective surfaces – a challenge that has previously required separate, unintegrated solutions.
2) Cross-Industry Scaling Service: Delivers a highly adaptable simulation framework that transforms complex thermal monitoring challenges into manageable solutions across industries. Unlike conventional monitoring systems that struggle with reflective surfaces and complex geometries, this service provides accurate temperature readings through an integrated approach that accounts for material properties. The service’s unique strength lies in its ability to handle massive parallel computations while maintaining accuracy.
3) Digital Twin Consulting Service: Offers a new approach to high-temperature monitoring in critical infrastructure of nuclear fusion devices by combining HPC-optimised workflow with advanced multi-physics simulation. Unlike traditional consulting services that focus on simulations this service provides a complete digital twin solution that can predict thermal distributions. The integration of ray-tracing algorithms with thermal modelling enables accurate temperature readings of highly reflective environments, setting it apart from conventional monitoring solutions.
