0

Full Content is available to subscribers

Subscribe/Learn More  >

Characterization of a Nanofluid Volumetric Solar Absorber / Steam Generator

[+] Author Affiliations
Robert A. Taylor, Patrick Phelan, Ronald Adrian, Andrey Gunawan

Arizona State University, Tempe, AZ

Todd Otanicar

Loyola Marymount University, Los Angeles, CA

Paper No. ES2011-54062, pp. 1927-1936; 10 pages
doi:10.1115/ES2011-54062
From:
  • ASME 2011 5th International Conference on Energy Sustainability
  • ASME 2011 5th International Conference on Energy Sustainability, Parts A, B, and C
  • Washington, DC, USA, August 7–10, 2011
  • ISBN: 978-0-7918-5468-6
  • Copyright © 2011 by ASME

abstract

Solar thermal energy has shown remarkable growth in recent years — incorporating many new technologies into new applications [1]. Nanofluids — suspensions of nanoparticles in conventional fluids — have shown promise to make efficient volumetric-absorption solar collectors [2–4]. It has also been shown that concentrated light energy can efficiently cause localized phase change in a nanofluid [5]. These findings indicate that it may be advantageous to create a ‘direct, volumetric nanofluid steam generator’. That is, a solar collector design which could minimize the number of energy transfer steps, and thus minimize losses in converting sunlight (via thermal energy) to electricity. To study this, we use a testing apparatus where concentrated laser light at 532 nm — a wavelength very near the solar spectrum peak — is incident on a highly absorbing sample. The highly absorbing samples compared in this study are black dyes, black painted surfaces, and silver nanofluids — with de-ionized water as a base fluid. Each of these samples converts light energy to heat — to varying degrees — in a localized region. This region is monitored simultaneously with a digital camera and an infrared camera. The resulting observed temperature profile and bubble dynamics are compared for these fluids. For pure water with a black backing, some very high temperatures (>300 °C) are observed with a laser input of ∼75 W/cm2 . Using a similar absorption potential, we observed higher temperatures in the nanofluids when compared to black dyes. A simplified boiling heat transfer analysis based on these results is also presented. We also noticed differences in bubble size and growth rates for the different samples. Overall, this study represents a proof-of-concept test for a novel volumetric, direct steam generator. These results of this test indicate that it may be possible to efficiently generate steam directly in a controlled, localized volume — i.e. without heating up passive system components.

Copyright © 2011 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In