Computer science for research

Modelling approaches

The vast majority of numerical activities carried out in the Centre relate to the modelling and simulation of all heat and mass transfer modes (heat conduction, convection, thermal radiation, phase change) as well as to the modeling of the thermal and radiative properties of heterogeneous media. The developments described cover also phenomenological aspects of components and energy systems. The three following transverse categories gather the differents tasks:

- non-isothermal and multiphase flows:

Heat transfer mode Turbulent convection and visco-elastic flows Two-phase flows involving boiling and bubble tracking Convection-radiation coupling
Methods DNS/LES and LBM VOF/Level-set DNS and DOM/Monte Carlo

- radiative and conductive heat transfer:

Heat transfer mode Thermal radiation   Heat conduction  
Length scale Macroscopic Micro to nanoscale Nanoscale

Monte Carlo / Symbolic Monte Carlo

Spectral modelling acceleration

Fluctuational electrodynamics DOM / Monte Carlo  

- components and energy-related systems:

Level of description Components Systems  
Methods Energy balance equations / Semi-empirical analyses Modal orthogonal decomposition Dynamical thermal models
  Grey-box approaches Model order reduction Artificial Intelligence (Neural Networks / Bayesian Inference)

Means of calculation

CETHIL has its own computation cluster service. For larger CPU-time calculations, CETHIL members have access to local infrastructures, such as those of the Federation de Calcul Lyonnaise, and national ones (IDRIS/CINES).

In-house simulation softwares:

Among the diverse tools developped, flagship softwares include OPAL (OpenCL Link-wise ACM on Many-core Processors), Open-CLAMP (OpenCL Processor Array Lattice Boltzmann Method solver), PAC-HT (Water Heat Pump at High Temperature), StaRPM (Statistical methods for Radiation in Participating Media), SLICE (Simplified L-distributions with ICE scheme), MuNeRa (Multilayer Near Field Radiative Heat Transfer).

Commercial simulation softwares:

Commonly-used softwares at CETHIL are thermal simulation tools, dynamical or not, adapted to multiphysics problems, energy systems, buildings and various other systems, including for instance COMSOL, StarCCM +, EES, TRNSYS.