Publication detail

The effect of changing surface emissivity on the natural ventilation rate of a narrow air cavity integrated in a transparent insulation façade

ČEKON, M. ČURPEK, J. SLÁVIK, R.

Original Title

The effect of changing surface emissivity on the natural ventilation rate of a narrow air cavity integrated in a transparent insulation façade

Type

conference paper

Language

English

Original Abstract

A transparent insulation material (TIM) can be incorporated in a building element in order to improve its thermal performance, including solar heat gain. However, some overheating protection needs to be implemented. The provision of natural ventilation in a façade cavity to avoid overheating, along with other potential techniques, could require a completely different approach to TIM integration in solar façade concepts. This paper concerns an analysis of the effect of different absorber emissivity behind a transparent insulation system. The emissivity changes are primarily studied in order to determine their effects on the overall radiation - natural convection heat transfer through a narrow façade air cavity. A comparative investigation was conducted using experimental full-scale dynamic outdoor tests and the building energy simulation (BES) approach. The thermodynamic response affected by the radiation - natural convection transfer is identified, specifically during the summer peak period, that corresponds to overheating. Depending on the ventilation regime, a low emissivity solar absorber inside a narrow air façade cavity may increase the cooling energy load and temperature response of a façade by 25 and 36%, respectively, in comparison with a high emissivity absorber. When the emissivity of the zone inside the cavity was changed, significant limitations were identified in the BES calculation methods for both vented and unvented cases.

Keywords

low emissivty; solar absorber;

Authors

ČEKON, M.; ČURPEK, J.; SLÁVIK, R.

Released

23. 10. 2019

Publisher

IOP Publishing

Location

Bristol

ISBN

1757-8981

Periodical

IOP Conference Series: Materials Science and Engineering

Year of study

609

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

6

Pages count

6

URL

https://iopscience.iop.org/article/10.1088/1757-899X/609/3/032054/pdf

BibTex

@inproceedings{BUT159753,
  author="Miroslav {Čekon} and Jakub {Čurpek} and Richard {Slávik}",
  title="The effect of changing surface emissivity on the natural ventilation rate of a narrow air cavity integrated in a transparent insulation façade",
  booktitle="10th International Conference IAQVEC 2019: Indoor Air Quality, Ventilation and Energy Conservation in Buildings",
  year="2019",
  journal="IOP Conference Series: Materials Science and Engineering",
  volume="609",
  pages="1--6",
  publisher="IOP Publishing",
  address="Bristol",
  doi="10.1088/1757-899X/609/3/032054",
  issn="1757-8981",
  url="https://iopscience.iop.org/article/10.1088/1757-899X/609/3/032054/pdf"
}