This project aims to develop a highly innovative heat exchangers using polymeric hollow fibers. Heat exchangers are crucial in all heat transfer processes including cooling and heating, which have a direct impact on carbon footprint. Studies have shown that polymeric hollow fiber heat exchangers have approximately seven times lower CO2 footprint than aluminium heat exchangers making them indisputably more environmentally preferable. Furthermore, due to lower density and more compact design the exchangers made of hollow fibers can dramatically reduce the weight of the system (typically more than 50%), making them more efficient, energy and fuel saving in automotive and aerospace as well in buildings as wall cooling and heating radiant systems for advanced air conditioning applications. Therefore, in relation to electric vehicles and smart urban mobility and smart cities this technology is an important upgrade which strongly supports the aim of the Joint Call focusing towards the first and second goal. In the proposed hollow fiber heat exchangers, a unique design is developed using bundles of hollow tubings with diameter about 1 mm and wall thickness roughly 10% of the diameter. This design allows for high heat transfer performance suitable for various applications including electronic cooling, flue gas cooling, air conditioning etc. Thanks to our special manufacturing process the hollow fibers can withstand high pressures (>4MPa), however, the very thin polymer wall presents a challenge because of the increased coolant leak through the wall especially apparent at elevated temperatures. To address this limitation, the present research proposal aims to find innovative solutions such as post-process surface treatments and co-extrusion manufacturing techniques that can, in a sustainable way, keep the advantages of low CO2 footprint and high efficiency while allowing for a long operational time and high durability.

Keywords
Hollow Fibers, Heat Exchanger, Electric vehicles, Air conditioning, Thermal management