A flamelet-based numerical framework for Conjugate Heat Transfer in LRE relevant conditions

In this contribution a numerical flamelet-based framework for turbulent combustion and Conjugate Heat Transfer (CHT) modeling is preliminary validated. The developed multi-region tool deals with both fluid and solid domains, solving the unsteady Reynolds Averaged Navier-Stokes (uRANS) equations within the former regions and the Fourier thermal equation in the latter. The solver takes advantage of several modeling solutions in order to overcome the intrinsic stiffness of the multi-scale and multi-physic problem considered. Among these, a flamelet-based turbulent combustion modeling approach is envisaged accounting for non-adiabatic effects, and thermal wall functions adapted for flamelet-based solvers are used to avoid the solution of the boundary layers. At the interface between contiguous domains a CHT condition is enforced, guaranteeing heat flux and temperature continuity. A loose coupling strategy is also proposed in order to accelerate the solution convergence and tackle the stiffness induced by the difference of the characteristic time-scales involved.