IDEAS home Printed from https://ideas.repec.org/a/gam/jeners/v18y2025i5p1139-d1599731.html
   My bibliography  Save this article

Vacuum-Insulated Glazing Assessment by CFD Modeling and Laboratory Measurements

Author

Listed:
  • Jacek Schnotale

    (Department of Environmental Engineering and Energy, Cracow University of Technology, 24 Warszawska Str., 31-155 Cracow, Poland)

  • Giorgio Baldinelli

    (Department of Engineering, University of Perugia, Via Duranti 67, 06125 Perugia, Italy)

  • Francesco Bianchi

    (National Institute for Nuclear Physics—Perugia, Via Pascoli, 06123 Perugia, Italy)

  • Agnieszka Lechowska

    (Department of Environmental Engineering and Energy, Cracow University of Technology, 24 Warszawska Str., 31-155 Cracow, Poland)

Abstract

This paper concerns measurements and CFD simulations of vacuum-insulated glazing (VIG), which consists of two glass panes separated by a narrow gap from which air has been removed. Distancers, e.g., in the form of small balls, are inserted into this gap every few centimeters to prevent the glass from deflecting. In the first part, simulations of two-pane VIG thermal transmittance with the Ansys Fluent program are described, resulting in thermal transmittance of VIG without the network of distancers equal to 2.18 W/(m 2 K) and with the distancers equal to 2.29 W/(m 2 K). The influence of the supports on the thermal transmittance of VIG is also determined. The CFD results show that the supporting balls increase the two-pane VIG thermal transmittance by about 0.15% with respect to the glazing without the distancers. Then, VIG is analyzed both numerically and tested in two measurement stands. Firstly, the tests are performed in a guarded hot-plate apparatus, according to the EN ISO 8302 standard. The two-pane glazing with one low-emissivity coating has a measured thermal transmittance equal to 1.75 W/(m 2 K). Other measurements were undertaken in the calorimetric chamber equipped with the hot-box apparatus. The results of the numerical assessment are then compared to the measurements of the existing three-pane vacuum-insulated glazing with two low-emissivity coatings, the same as simulated. The procedure follows the EN ISO 8990 standard. Measurement results of 1.10 W/(m 2 K) are compared to the simulation results of VIG thermal transmittance equal to 1.09 W/(m 2 K). A satisfactory agreement is reached. Additionally, this paper considers a new correction coefficient to thermal transmittance according to standard EN 673 in order to achieve a proper calculation of vacuum-insulated glazing in the center-of-glass region. The authors propose to use an adjustment coefficient of 1.05 when calculating the thermal transmittance of vacuum-insulated glazing without taking into account convection in the vacuum space and the thermal influence of distancers.

Suggested Citation

  • Jacek Schnotale & Giorgio Baldinelli & Francesco Bianchi & Agnieszka Lechowska, 2025. "Vacuum-Insulated Glazing Assessment by CFD Modeling and Laboratory Measurements," Energies, MDPI, vol. 18(5), pages 1-17, February.
    • Handle: RePEc:gam:jeners:v:18:y:2025:i:5:p:1139-:d:1599731
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/1996-1073/18/5/1139/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/1996-1073/18/5/1139/
    Download Restriction: no
    ---><---

    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:18:y:2025:i:5:p:1139-:d:1599731. 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.

    We have no bibliographic references for this item. You can help adding them by using 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.