Tue, 03 October, 2023
As part of TWI’s investment in new technologies, we have completed the design phase of an innovative research and development project, funded under theTWI Exploratory Programme, to further develop low density alloy printed circuit heat exchangers (PCHEs), using Al-alloys as a demonstration case, in support of the drive towards Net Zero.
The PCHE demonstrator has been designed to be a simplified, scaled-down but representative unit. It involves a stack of photo-chemically etched shims, which contain channel geometries, sandwiched between end plates, and diffusion bonded using TWI’s proprietary Al-diffusion bonding technique.
TWI has been working with an industrial partner to produce the photochemically etched shims, as shown in Figure 1, below:
Figure 1. CAD drawing of one of the ‘hot’ shims of the heat exchanger
Each layer incorporates zig-zag channels (semi-circular in shape, with a diameter of 500µm) and built-in headers. The design is a cross-flow concept, with each individual layer alternating between the hot and the cold working fluids and the microchannels stacked directly in line with each other.
Figure 2. CAD images showing the diffusion bonded PCHE demonstrator
The shim stack consists of 30 hot and 30 cold shims situated between two thick end plates.
TWI is currently targeting completion of the PCHE demonstrators by mid-November 2023.
Following this, a further article will published to showcase these. However, if there are any immediate queries, please feel free to get in contact with us.