Events

 

The EU-funded PANTTHER project, coordinated by the von Karman Institute for Fluid Dynamics (VKI) aimed to understand the flow maldistribution in multiphase heat exchangers as well as characterize the effect of using low GWP refrigerants. The project partnered with TEMISTH, with LIEBHERR Aerospace a topic leader. The project started in September 2020 for a duration of 36 months and an estimated budget of € 1 196 128,75. During this project, two experimental installations were built. The first is a simplified version of an evaporator header, with air/water in flow similarity where a complete study of the effect of many parameters (such as inlet pipe position, presence of protrusions, header orientation) on the flow distribution in the header was performed using Design of Experiments. To allow this extensive study, an innovative two-phase flow metering technique using a venturi solely was developed. The second is an vapor cycle system that was first used to build a database of R1234ze evaporation in a 10 mm horizontal pipe, and then perform a similar study on the effect of parameters as done with the air/water setup. Qualitatively similar results were obtained. On the numerical side, a diphasic, 3D, hydraulic and thermal laminar topological optimization solver was developed. In parallel, simulations of the full heat exchanger were performed where the core is modelled with a diphasic 3D porous media approach with phase change, while the header is modelled with a MMP approach. Three journal papers, almost 10 conference papers, and a video of the refrigerant setup was generated.