IDEAS home Printed from https://ideas.repec.org/a/gam/jeners/v6y2013i12p6304-6321d30991.html
   My bibliography  Save this article

Thermal CFD Analysis of Tubular Light Guides

Author

Listed:
  • Ondřej Šikula

    (Faculty of Civil Engineering, Brno University of Technology, Veveří 331/95, Brno 602 00, Czech Republic)

  • Jitka Mohelníková

    (Faculty of Civil Engineering, Brno University of Technology, Veveří 331/95, Brno 602 00, Czech Republic)

  • Josef Plášek

    (Faculty of Civil Engineering, Brno University of Technology, Veveří 331/95, Brno 602 00, Czech Republic)

Abstract

Tubular light guides are applicable for daylighting of windowless areas in buildings. Despite their many positive indoor climate aspects they can also present some problems with heat losses and condensation. A computer CFD model focused on the evaluation of temperature distribution and air flow inside tubular light guides of different dimensions was studied. The physical model of the tested light guides of lengths more than 0.60 m proves shows that Rayleigh numbers are adequate for a turbulent air flow. The turbulent model was applied despite the small heat flux differences between the turbulent and laminar model. The CFD simulations resulted into conclusions that the growing ratio of length/diameter increases the heat transmission loss/linear transmittance as much as by 50 percent. Tubular light guides of smaller diameters have lower heat transmission losses compared to the wider ones of the same lengths with the same outdoor temperature being taken into account. The simulation results confirmed the thermal bridge effect of the tubular light guide tube inside the insulated flat roof details. The thermal transmittance of the studied light guides in the whole roof area was substituted with the point thermal bridges. This substitution gives possibility for simple thermal evaluation of the tubular light pipes in roof constructions.

Suggested Citation

  • Ondřej Šikula & Jitka Mohelníková & Josef Plášek, 2013. "Thermal CFD Analysis of Tubular Light Guides," Energies, MDPI, vol. 6(12), pages 1-18, December.
    • Handle: RePEc:gam:jeners:v:6:y:2013:i:12:p:6304-6321:d:30991
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/1996-1073/6/12/6304/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/1996-1073/6/12/6304/
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Al-Marwaee, Mohammed & Carter, David, 2006. "Tubular guidance systems for daylight: Achieved and predicted installation performances," Applied Energy, Elsevier, vol. 83(7), pages 774-788, July.
    2. Probert, S.D. & Thirst, T.J., 1980. "Design and performance of roofs," Applied Energy, Elsevier, vol. 6(2), pages 79-97, March.
    3. Batty, W. J. & O'Callaghan, P. W. & Probert, S. D., 1984. "Energy and condensation problems in buildings," Applied Energy, Elsevier, vol. 17(1), pages 1-14.
    Full references (including those not matched with items on IDEAS)

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Allen Jong-Woei Whang & Tsai-Hsien Yang & Zhong-Hao Deng & Yi-Yung Chen & Wei-Chieh Tseng & Chun-Han Chou, 2019. "A Review of Daylighting System: For Prototype Systems Performance and Development," Energies, MDPI, vol. 12(15), pages 1-34, July.
    2. Anderson Diogo Spacek & João Mota Neto & Luciano Dagostin Biléssimo & Oswaldo Hideo Ando Junior & Gustavo Pedro De Freitas Neto & Rodrigo Da Silva Giansella & Marcus Vinícius Ferreira De Santana & Cel, 2017. "Proposal for an Experimental Methodology for Evaluation of Natural Lighting Systems Applied in Buildings," Energies, MDPI, vol. 10(7), pages 1-12, July.
    3. Cristina Baglivo & Marina Bonomolo & Paolo Maria Congedo, 2019. "Modeling of Light Pipes for the Optimal Disposition in Buildings," Energies, MDPI, vol. 12(22), pages 1-28, November.
    4. Kocifaj, M., 2009. "Efficient tubular light guide with two-component glazing with Lambertian diffuser and clear glass," Applied Energy, Elsevier, vol. 86(7-8), pages 1031-1036, July.
    5. Magda Sibley & Antonio Peña-García, 2020. "Flat Glass or Crystal Dome Aperture? A Year-Long Comparative Analysis of the Performance of Light Pipes in Real Residential Settings and Climatic Conditions," Sustainability, MDPI, vol. 12(9), pages 1-11, May.
    6. Anderson Diogo Spacek & João Mota Neto & Luciano Dagostin Biléssimo & Oswaldo Hideo Ando Junior & Marcus Vinícius Ferreira de Santana & Celia De Fraga Malfatti, 2018. "Proposal of the Tubular Daylight System Using Acrylonitrile Butadiene Styrene (ABS) Metalized with Aluminum for Reflective Tube Structure," Energies, MDPI, vol. 11(1), pages 1-12, January.
    7. Salata, Ferdinando & Golasi, Iacopo & di Salvatore, Maicol & de Lieto Vollaro, Andrea, 2016. "Energy and reliability optimization of a system that combines daylighting and artificial sources. A case study carried out in academic buildings," Applied Energy, Elsevier, vol. 169(C), pages 250-266.
    8. Mayhoub, M.S. & Elqattan, Ahmed A. & Algendy, Algendy S., 2021. "Experimental investigation of dust accumulation effect on the performance of tubular daylight guidance systems," Renewable Energy, Elsevier, vol. 169(C), pages 726-737.
    9. Li, Danny H.W. & Tsang, Ernest K.W. & Cheung, K.L. & Tam, C.O., 2010. "An analysis of light-pipe system via full-scale measurements," Applied Energy, Elsevier, vol. 87(3), pages 799-805, March.

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jeners:v:6:y:2013:i:12:p:6304-6321:d:30991. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a bibliographic reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.