Performance of a tubular direct absorption solar collector with a carbon-based nanofluid
Peer reviewed, Journal article
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OriginalversjonStruchalin, P. G., Yunin, V. S., Kutsenko, K. V., Nikolaev, O. V., Vologzhannikova, A. A., Shevelyova, M. P., Gorbacheva, O. S., & Balakin, B. V. (2021). Performance of a tubular direct absorption solar collector with a carbon-based nanofluid. International Journal of Heat and Mass Transfer, 179. 10.1016/j.ijheatmasstransfer.2021.121717
Direct absorption solar collectors (DASC) with nanofluid represent a new direction in solar thermal technology that is simpler yet more efficient than conventional equipment. In this work, we report details of performance for a custom tubular DASC with a carbon-based nanofluid. The collector was tested experimentally following a standard procedure and using a multiphase CFD-model of the device. The experiments were carried out in a range of flow rates 2... 10 l/min, nanoparticle concentrations 0.0015... 0.082%wt., temperature differences (up to 29.3 degrees), and radiant heat fluxes. We found that, at a particle concentration of 0.01%, the collector demonstrated the average thermal efficiency of 80%. For the comparable temperature differences, the efficiency of DASC was 5.8... 37.9% higher than a collector with similar geometry but a surface absorption of light energy. The CFD-model, validated against our experiments, depicts flow patterns in the DASC focusing on nanoparticles’ deposition. Less than 5% of particles deposit under local flow restrictions at flows above 6 l/min. The deposition patterns from the CFD-model correlate to the experimental observations.
This is an author's accepted manuscript version of an article published by Elsevier in International Journal of Heat and Mass Transfer on 19 July 2021, available from https://doi.org/10.1016/j.ijheatmasstransfer.2021.121717