Simulation and modelling of heat transfer in two-phases turbulent bubbly flows

This thesis is organised in two parts. The first part deals with the modelling of heat transfer in bubble flows in the absence of thermal property jumps. The code TrioCFD-IJK is used to simulate these flows with the interface tracking method, the single-fluid formulation and finite volume schemes. Examples of simulations in both single and two-phase channels are presented to show the ability of the code to describe the temperature in turbulent flows. These studies allow a validation of the code under these conditions and new results concerning heat transfer as a function of the liquid Prandtl number. Finally, a detailed study with convergence in mesh has been carried out on the case of a homogeneous swarm of bubbles. It reveals correlations of heat transfers at the interfaces, in swarms, very close to the correlations deduced on single bubbles, but still presenting an intensification of the transfers of the order of 10% for Prandtl numbers in the studied conditions. In a second part, a search for a reliable numerical formulation for the simulation of flows with jump in thermal properties is conducted. The light and flexible 1D code FluidDyn is developed in Python. It is used to develop and validate new convection-diffusion schemes for bubble flows. Several studies are conducted in a case with property jumps and allow to derive a new one-dimensional conservative formulation. This formulation is finally adapted to the three-dimensional case, requiring in particular a certain number of calculations of intersections of meshes and interpolations, specific to the front-tracking. These geometric developments also allow the analysis of the interpolated fields at the interfaces in the context of the temperature single-fluid formulation, which is essential for taking the interfacial statistics necessary to obtain the swarm correlations. (author)