Manufacture, solar transmission, and heat transfer characteristics of large-celled honeycomb transparent insulation

• Published in: Solar energy 1992-11, Vol.49 (5), p.381-385
• Main Authors: Hollands, K.G.T., Iynkaran, K., Ford, C., Platzer, W.J.
• Format: Article
• Language: English
• Subjects: 141000 - Solar Collectors & Concentrators; AISLAMIENTO; Applied sciences; CAPTEUR SOLAIRE; COLECTORES SOLARES; DESEMPENO; ECHANGE THERMIQUE; ENERGIA SOLAR; ENERGIE SOLAIRE; Energy; ENERGY TRANSFER; Exact sciences and technology; FABRICATION; FORECASTING; HEAT TRANSFER; HONEYCOMB STRUCTURES; INSULATING MATERIALS; INSULATION; ISOLATION; low emissivity surfaces; Manufacturing; MATERIALS; MEASUREMENT; MECHANICAL STRUCTURES; MEDICION; MESURE; Natural energy; OPTICAL PROPERTIES; PETROCHEMICALS; PETROLEUM PRODUCTS; PHYSICAL PROPERTIES; PLASTICS; POLYMERS; PREDICTION; PROPIEDADES OPTICAS; PROPIEDADES TERMICAS; PROPRIETE OPTIQUE; PROPRIETE THERMIQUE; RADIANT HEAT TRANSFER; RADIATIONS; SOLAR COLLECTORS; SOLAR ENERGY; SOLAR EQUIPMENT; SOLAR RADIATION; Solar thermal conversion; STELLAR RADIATION; SYNTHETIC MATERIALS; TECHNIQUE DE PREVISION; TECNICAS DE PREDICCION; THERMAL CONDUCTIVITY; thermal emittance; THERMAL INSULATION; THERMAL PROPERTIES; THERMODYNAMIC PROPERTIES; Thermodynamics; TRANSFERENCIA TERMICA; TRANSMITTANCE
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/0038-092X(92)90110-V

A method for manufacturing thin-walled (about 20 μm wall thickness), large-celled (about 10 mm hydraulic diameter of cell) honeycomb from FEP plastic is described. The honeycomb manufacturing method uses heat-sealing to join adjacent strips of plastic along thin lines. The honeycomb is sized to be just small enough to suppress convection, but in itself it provides little radiant suppression, so it is intended to be used in conjunction with low emissivity surfaces at one or both of its bounding faces to provide the necessary radiant reduction. In addition to the method for manufacture, measurements of the honeycomb's thermal conductance and solar transmittance are also reported. Mounted adjacent to a face with a thermal emittance of 0.1, a 40 mm deep honeycomb achieved thermal conductance values ranging from 1.4 to 2.4 W/m 2 K when the temperature difference ranged from 10 to 80 K and the mean temperature from 290 to 360 K. At an angle of incidence of 45°, the honeycomb achieved a solar transmittance of 92%.