The purpose of this study is the distribution optimization of a two-phase fluid in a small-channel evaporator. A measurement method, based on infrared thermography, was developed to characterize the heat transfer distribution over the heat exchanger wall, which is representative of the fluid distribution. This method was validated on a small-channel evaporator model with a single-phase fluid, and then with an air-water mixture. The influence of flow rate and quality on the fluid distribution has been studied, along with the orientation of the exchanger. It was revealed that the distribution in the heat exchanger is highly dependent on the inertia of the liquid phase of the fluid. The introduction of a porous body in the header limits this effect. A numerical simulation tool for the distribution of two-phase fluid (air-water and refrigerant) in an evaporator has been developed and was validated by experimental results.
