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Additive Manufacturing
Additive manufacturing : lights out manufacturing onsite at Conflux ’ s vertically integrated facility .
Novel materials and processes – Research into new materials with complex micro and nano structures is yielding many applications across the energy sector 2 . More immediately for heat exchangers , new alloys with high thermal conductivity , low weight and high durability are being investigated . Distributed manufacture – An additively manufactured part has the potential to be “ printed ” close to or at the site of use , without relying on highly specialized tooling . Whilst significant complexities are currently involved – such as post-processing requirements , machine calibration and IP protection – this has long term potential to reduce transport costs , inventory levels , supply chain risks and further enhance serviceability in the long term .
How do you create large scale heat exchangers using AM ? Additive manufacturing is still developing the appropriate techniques to “ print metal ” at the large scales required . There are two paths – enlarging machines and creating modular arrays . But how big can you print a metal heat exchanger ? To be able to print the small scale features , laser powder bed fusion ( LPBF ) machines are generally used . The footprint able to be printed on commercially available machines is currently limited to sub-1m 3 . For example , AMCM customizes EOS machines , and has developed a machine that is able to reach 450 × 450 × 1000 mm 3 . Other technologies such as Directed Energy Deposition promise larger volumes with lower resolution 4 . To satisfy the needs of this situation we look to the design and consider a set of modular components .
Modular arrays A modular array is a set of cell parts designed to join and form a larger unit . A modular design offers a host of potential benefits ; flexibility , configuration , scaling , customization of individual parts , evolution of design , single unit replacement and serviceability . Modularity in heat exchangers is not a new concept – plate , PCHE and welded heat exchangers all support modularity via layering of repeating elements within a unit or by series or parallel linking of units . As well as allowing for scaling beyond a single unit , modules can be reconfigured , or individual units can be removed and maintained without having to shut down the entire process ( for example , by closing a set of valves ). When considering large scale energy production the appeal of being able to maintain constant production is of high value given the financial gain . Disadvantages include the potential for leak points at joins , ‘ dead areas ’ at joints that lower the efficiency for a certain volume and raise complexity and costs . Reliable joining of modules without compromising integrity or overengineering
54 Heat Exchanger World September 2022 www . heat-exchanger-world . com