Optimization of nanofluid volumetric receivers for solar thermal energy conversion
Author(s)
Lenert, Andrej; Wang, Evelyn N.; Wang, Evelyn
DownloadPost-print.pdf (5.407Mb)
PUBLISHER_CC
Publisher with Creative Commons License
Creative Commons Attribution
Terms of use
Metadata
Show full item recordAbstract
Improvements in solar-to-thermal energy conversion will accelerate the development of efficient concentrated solar power systems. Nanofluid volumetric receivers, where nanoparticles in a liquid medium directly absorb solar radiation, promise increased performance over surface receivers by minimizing temperature differences between the absorber and the fluid, which consequently reduces emissive losses. We present a combined modeling and experimental study to optimize the efficiency of liquid-based solar receivers seeded with carbon-coated absorbing nanoparticles. A one-dimensional transient heat transfer model was developed to investigate the effect of solar concentration, nanofluid height, and optical thickness on receiver performance. Simultaneously, we experimentally investigated a cylindrical nanofluid volumetric receiver, and showed good agreement with the model for varying optical thicknesses of the nanofluid. Based on the model, the efficiency of nanofluid volumetric receivers increases with increasing solar concentration and nanofluid height. Receiver-side efficiencies are predicted to exceed 35% when nanofluid volumetric receivers are coupled to a power cycle and optimized with respect to the optical thickness and solar exposure time. This work provides insights as to how nanofluids can be best utilized as volumetric receivers in solar applications, such as receivers with integrated storage for beam-down CSP and future high concentration solar thermal energy conversion systems.
Date issued
2011-10Department
Massachusetts Institute of Technology. Department of Mechanical EngineeringJournal
Solar Energy
Publisher
Elsevier
Citation
Lenert, Andrej and Wang, Evelyn N. "Optimization of nanofluid volumetric receivers for solar thermal energy conversion." Solar Energy 86, no. 1 (January 2012): 253-265. © 2011 Elsevier Ltd
Version: Author's final manuscript
ISSN
0038-092X