MEDIÇÕES ESPECTROFOTOMÉTRICAS DE SISTEMAS DE JANELA UTILIZANDO LÍQUIDOS TRANSPARENTES (TRANSWALLS)
DOI:
https://doi.org/10.46421/entac.v17i1.1447Keywords:
Transwall, Spectrometry, Water wall, Spectrally selective, Façade's innovationAbstract
This paper presents the measurement of specular transparent liquid's spectroscopy in the solar wavelength range with normal incidence for Transwall filling purposes. Transwalls can be described as passive solar building's envelope system with direct light gains, but thermal attenuation (spectral selectivity). It has been tested different samples of water, solutions, alcohols and acids, so as float glass 3mm and two prototypes varieties: double glass with internal spacing (gap) of 2mm and 10mm filled with the liquids listed above or empty. All experiments have been carried out in the spectrophotometer Lambda 1050 and compared by Visible Transmittance (Tvis) and Solar Transmittance (Tsolar). Also, Tvis and Tsolar data from 4mm green glass and 12mm Azuria glass have been collected from the National Fenestration Rating Council (NFRC) list for analogy purposes. The results have shown promising spectral selectivity of thin water samples with higher light transmittance than double glass systems and considerable infrared attenuation. Also, the measurements pointed the impact internal reflections can cause to light transmittance when varying from air to water refractive index.
References
ASTM - AMERICAN SOCIETY FOR TESTING AND MATERIALS. E903-96: Standard TestMethod for Solar Absorptance, Reflectance and Transmittance of Materials UsingIntegrating Spheres, 1996.
ASTM - AMERICAN SOCIETY FOR TESTING AND MATERIALS. G173-03: Standard Tablesfor Reference Solar Spectral Irradiances - Direct Normal and Hemispherical on 37°Tilted Surface. ASTM International, 2003.
CARAM, R. M. Estudo e Caracterização de Fachadas Transparentes para Uso naArquitetura: Ênfase na Eficiência Energética. 2002. 189p. Texto (Livre-Docência) -Escola de Engenharia de São Carlos, Universidade de São Paulo, São Carlos.
FUCHS, R.; MCCLELLAND, J.f.. Passive solar heating of buildings using a transwallStructure. Solar Energy, [s.l.], v. 23, n. 2, p.123-128, 1979. Elsevier BV.http://dx.doi.org/10.1016/0038-092x(79)90112-9.
MARINOSKI, D., et al. Análise comparativa de valores de refletância solar desuperfícies opadas utilizando diferentes equipamentos de medição em laboratório.
In: XII ENCONTRO NACIONAL DE CONFORTO DO AMBIENTE CONSTRUÍDO. Set. 2013,Brasília.
NAYAK, J. Thermal performance of a water wall. Building and Environment, vol. 22, 1,1987 (1987a), páginas 83-90. https://doi.org/10.1016/0360-1323(87)90045-XNAYAK, J. Tranwall versus trombe wall: relative performance studies. EnergyConversion & Management, Vol. 27, No. 4, 1987 (1987b), páginas 389-393. DOI:10.1016/0196-8904(87)90117-8NISBET, S.; KWAN, C. The application of the transwall to horticultural glasshouses. SolarEnergy, [s.l.], v. 39, n. 6, p.473-482, 1987. Elsevier BV. http://dx.doi.org/10.1016/0038-092x(87)90054-5.
NISBET, S.k.; MTHEMBU, N.s.. Transwall modelling using effective conductivities. SolarEnergy, [s.l.], v. 49, n. 2, p.127-138, ago. 1992. Elsevier BV.http://dx.doi.org/10.1016/0038-092x(92)90147-3.
PAPERSENOS, George, F. The analysis of the transwall passive solar system. 1983.
291p. Texto (PhD) Universidade de Glasgow, Glasgow, Escócia.
WU, T; LEI, C. Thermal modelling and experimental validation of a semi-transparentwater wall system for Sydney climate. Solar Energy, volume 136, 15 out. 2016 (2016c),páginas 533-546. https://doi.org/10.1016/j.solener.2016.07.026.
