Heat transfer through a double-glazed unit with an internal louvered blind: Determination of the thermal transmittance using a biquadratic equation

Urbikain, M. Karmele; Sala, J.M.

doi:10.1016/j.ijheatmasstransfer.2011.09.032

Cited by 12 publications

(3 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to decreasing thermal radiation from the window surface, blinds act as a thermal barrier for individuals near the window [13,[27][28][29]. Numerous studies have explored the advantages and considerations of utilising interior roller blinds as shading solutions in hot climates, as cited in References [30][31][32][33]. This study specifically examines the utilisation of top-down interior roller opaque blinds in spaces throughout Najran University.…”

Section: Solar Heat Gain Through Glazing With Interior Roller Blindsmentioning

confidence: 99%

Aesthetic and Thermal Suitability of Highly Glazed Spaces with Interior Roller Blinds in Najran University Buildings, Saudi Arabia

Qahtan

2024

Sustainability

View full text Add to dashboard Cite

Highly glazed spaces are visually appealing and trendy, but effectively managing their temperature in hot arid climates remains a significant challenge. This study evaluates the effectiveness of dark-tinted double low-E glass with internal roller blinds in reducing heat gain in glazed spaces in hot arid climates and investigates architects’ perspectives on these facades. It combines field measurements and a survey to assess the balance between thermal control and aesthetics in such environments. This study reveals that the current glazing significantly attenuates solar radiation ingress, evidenced by a marked indoor-–outdoor temperature differential (ΔT) of approximately 9.2 °C. The mean radiant temperature registers at 1.5 °C above the indoor air temperature, which can be attributed to the glazing’s propensity to absorb and retain solar heat, resulting in an inner glass surface temperature of 43 °C. The implementation of adjustable blinds has a dynamic influence on the heat transfer coefficient (HTC), effectively modulating the temperature by impeding natural convection currents. With the blinds retracted, the HTC stands at an average of 7.1 W/m2K, which diminishes to 5 W/m2K when the blinds are 50% closed and further reduces to 4.2 W/m2K when the blinds are fully closed (100%). Survey results suggest that architects prioritise glazed facades for aesthetics (52%) while facing challenges in thermal and energy efficiency (44%). Future studies should concentrate on developing novel glazing systems that integrate solutions for visual appeal, lighting and thermal efficiency in glazed facades, particularly in hot arid climates.

show abstract

Section: Solar Heat Gain Through Glazing With Interior Roller Blindsmentioning

confidence: 99%

Aesthetic and Thermal Suitability of Highly Glazed Spaces with Interior Roller Blinds in Najran University Buildings, Saudi Arabia

Qahtan

2024

Sustainability

View full text Add to dashboard Cite

show abstract

“…As shown in Table 1, four materials were used in the simulation in ABAQUS software. The thermal properties of the materials used are presented in Table 1 [11,12,14]. Figure 4a shows the assembly model of one room with three walls, columns and slab.…”

Section: Thermal Properties Of Masonry Bricks and Plastermentioning

confidence: 99%

Thermal Simulation for a Room with Solid and One-Way Ribbed Slab Using FEM

Al-Tamimi¹,

Al‐Osta²,

Al‐Amoudi³

et al. 2017

Proceedings of the 2nd World Congress on Civil, Structural, and Environmental Engineering

View full text Add to dashboard Cite

Heat transfer has become of great importance due to the excessive energy consumption, which is greatly affected by the amount of thermal flow to the inner surfaces of the building envelope (walls and roof). In this investigation, thermal analysis of a room (slab, walls, columns and plaster) was conducted with two types of slab (solid slab and one-way-ribbed slab) using finite element model (FEM) with ABAQUS software to investigate the effect of slab type and plastering on the overall inner surface temperature of the room. Plastering with thickness of 1 cm was used from both sides of the room envelopes. Results of the FEM indicate that the ribbed slab was more thermally efficient than the solid one by about 19% and 17% for plastered and non-plastered slabs, respectively. For the overall inner temperature of the room, the room with ribbed slab was more thermally resistant than that with the solid one by approximately 38%. The effect of plaster with ribbed slab had a little increment on the thermal resistance compared to the solid one by about 0.55°C; while the effect was negligible in the case of walls. The effect of mortar on temperature increment of the wall was 0.56°C. For the room with solid slab, the inner surface temperature for one wall was almost the same for both plastered and non-plastered walls, while it was 0.73°C for the room with ribbed slab because the beams (30 cm thickness) increased the heat flow to the upper face of the wall. The heat flow from the ribbed slab to the columns was much higher than the solid one by about 3.11%. However, the room with ribbed slab was more comfortable from thermal point of view as compared to the room with solid slab.

show abstract

“…Study of various single, double Low-E glazing's, thermo tropic and photovoltaic windows by using them as building envelope in all orientations to find which would minimise the solar energy consumption in the building for different climatic regions in Malaysia country were reported in detail [7]. To find out the heat transfer through single Low-E and double Low-E glass windows considering the entire wave length region in solar spectrum by changing the position of window glasses to decrease the solar radiation in summer and to increase the solar radiation in winter seasons for an adiabatic room was studied [8].To find the direct solar radiation into buildings at various inward window tilt glasses in all directions of buildings, for six latitudes of India and found that in south direction it achieved zero radiation for all the four different window glass materials like clear, bronze, green and bronze reflective were studied in [9]. To analyze the heat transfer through internal louvered blind with high and low thermal conductivity in double-glazed unit to find the thermal transmittance by using and comparing a biquadratic equation and also with computational fluid dynamics at different places was studied [10].…”

Section: Introductionmentioning

confidence: 99%

Thermal and cost analysis of float and various tinted double window glass configurations on heat gain into buildings of hot & dry climatic zone in India

Gorantla¹,

Shaik²,

Setty³

2018

IJHT

View full text Add to dashboard Cite

Glass window enclosures for buildings consume a lot of energy for affording thermal and visual comfort. Reducing solar radiation in summer and increase in winter through different double window glasses for making energy efficient building design is the theme of this paper. Therefore this work measures the spectral characteristics of four glasses namely grey, green, bronze and clear glasses in entire solar spectrum region from 300nm to 2500nm at normal angle of incidence by using Shimadzu UV 3600 spectrophotometer based on ASTM standards. To find the solar optical properties a MATLAB code was used which is based on British standards. To find the solar radiation transmission from different double window glass configurations and cost analysis from eight coordinal directions at peak summer and winter day were selected as per Indian standards with a MATLAB code to hot and dry climatic zone of Jodhpur (26.300N, 73.020E). From these results it is shows that in south direction all double glass windows are gaining less heat in summer and more heat in winter season when compared to other orientations. It is found that south orientation C1(Greyglasswindow-Airgap10mm-Greenglasswindow) and C12(Clearglasswindow-Airgap10mm-Bronzeglasswindow) configuration windows are gaining minimum and maximum heat in summer and winter respectively when compared to other configuration windows. Among all windows C1 configuration window is saving more cost annually.

show abstract

Heat transfer through a double-glazed unit with an internal louvered blind: Determination of the thermal transmittance using a biquadratic equation

Cited by 12 publications

References 12 publications

Aesthetic and Thermal Suitability of Highly Glazed Spaces with Interior Roller Blinds in Najran University Buildings, Saudi Arabia

Aesthetic and Thermal Suitability of Highly Glazed Spaces with Interior Roller Blinds in Najran University Buildings, Saudi Arabia

Thermal Simulation for a Room with Solid and One-Way Ribbed Slab Using FEM

Thermal and cost analysis of float and various tinted double window glass configurations on heat gain into buildings of hot & dry climatic zone in India

Contact Info

Product

Resources

About