In this project, a completely new, greatly improved rotor for the rotary heat pump based on MCDB (Microchannel diffusion bonding) technology will be developed and prototyped.
MCDB is a fabrication technique used to join layers of metal — often in heat exchangers or microreactors — without using adhesives or welding. The process involves placing the layers with precisely etched microchannels in contact under high temperature and pressure, allowing atoms to diffuse across the interface and form a solid-state bond. This creates a seamless, leak-free structure that maintains the integrity of the microchannels and ensures excellent thermal and mechanical performance.
Ecop has recognized that MCDB technology is suitable for manufacturing a significantly improved rotor for heat pump technology, which, due to its high strength, is capable of achieving temperature lifts of 100K and more.
In this project, the new rotor, the water and gas connections of the heat pump, and the housing were completely redesigned. MCDB technology was used for the first time to realize the entire thermodynamic cycle in a microchannel diffusion bonded block.
At first, the thermodynamic design of the block needed to be developed and evaluated by extensive CFD simulations and the creation of a digital twin.
Afterwards, the thermodynamic design was realized, whereas the construction of the rotor needed to be calculated extensively by FEM simulations in order to guarantee the safety of the structure.
Each and every design change needed to be evaluated by both, CFD and FEM sumualtion which made the development process very lengthy.
At the same time, water distribution, ventilation, including the design of an even more powerful ventilation motor of 300kW, and a completely new housing was designed.
At the end, although the design concepts of the machine with exception of the rotor remained the same, the nearly the entire machine was newly designed.
To better understand the influence of etching and bonding for the final rotor geometry and production process, a PoC of a rotor block was manufactured and intensively measured (dimensions, leakage and material tests). As the results were as expected, the first rotor, composed of a total of 5 diffusion-bonded sub-blocks, was realized. The production was very complicated as the rework of the blocks needed to be done very carefully.
At the same time, all the other assembly groups of the machine were developed and assembled.
