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Design
New channel design for supercritical CO2 power cycles
Typical straight and zig-zag channels in PCHE .
The renewable energy sector is pushing the boundaries of technology to deliver cleaner , more efficient solutions . One of the most significant challenges that project teams face is striking the right balance between thermal efficiency and pressure drop when selecting heat exchangers , all while meeting the growing demand for compact equipment . As many projects move toward modularisation , the importance of compact and highly efficient heat exchangers becomes paramount . This challenge is particularly evident in the development of supercritical CO2 ( sCO2 ) power cycles for concentrated solar power ( CSP ) plants .
Text & images by Kelvion
Kelvion , a global provider of heat exchanger technology , is pioneering solutions for the challenges faced by the renewables sector through innovative channel designs for printed circuit heat exchangers ( PCHEs ). By introducing a new PCHE channel pattern , Kelvion is transforming the performance of sCO2 power cycles , marking a significant milestone in the evolution of green technologies .
SCARABEUS project : the genesis of innovation Kelvion ’ s journey towards redefining heat exchanger design began in 2019 with the SCARABEUS project , an initiative aimed at optimising sCO2 cycles for concentrated solar power plants ( CSP ). As part of this groundbreaking European research project , involving nine renowned industry and academic partners , the company committed itself to developing advanced solutions for blended CO2 cycles in CSP applications . The SCARABEUS project provided Kelvion with a platform to innovate and refine its K ° BOND heat exchangers , specifically optimising the flow dynamics within PCHEs . “ We improved the flow dynamic by innovating new internal shapes , departing from the conventional straight and zig-zag channels ,” says Roy Niekerk , business developer at Kelvion . “ The new pattern significantly reduces pressure drop while maintaining superior heat transfer coefficients .”
Supercritical CO2 power cycles : an emerging technology Supercritical CO2 power cycles use carbon dioxide in a supercritical state , where it is above its critical temperature and pressure , making it neither a distinct liquid nor gas . This unique state offers several advantages for power generation . Unlike traditional steam cycles , which use water or steam as a working fluid , sCO2 cycles use CO2 , which operates at lower critical pressures and with a higher fluid density . These properties allow for more compact systems with smaller components , offering potential reductions in capital costs and plant footprint . [ 2 ] One of the major benefits of sCO2 cycles is their efficiency . The near-incompressibility of supercritical CO2 at critical points significantly reduces compression work compared to steam cycles , while the fluid ’ s high critical temperature allows for effective heat rejection even at ambient temperatures . As a result , sCO2 cycles achieve higher thermal efficiency across various applications , from fossil fuels to renewable sources like solar and geothermal energy .
Innovating PCHEs PCHEs are critical to the efficiency of supercritical CO2 power cycles . These compact , high-efficiency heat exchangers are produced using a combination of chemical
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