Ventilated Double-skin Facade Research Articles

Airflow modeling based on zonal method for natural ventilated double skin façade with Venetian blinds

A zonal method based on the airflow model is developed to predict the temperature and airflow of the natural ventilated double skin facade (DSF) with Venetian blinds. Ventilation theories such as the Bernoulli equation, thermal pressure, and airflow network method are used to establish the airflow model. It is validated by the experimental data. The validation results show that the simulated results agree well with the experimental data. In addition, some factors that influence the temperature and airflow rate are discussed. It is found that the slat angle, air cavity thickness, and DSF height have different influences on the temperature and airflow rate of the natural ventilated DSFs with Venetian blinds. Meanwhile, changing the vent area has little influence on the thermal performance. This model is suitable for the dynamic modeling of natural ventilated DSFs with Venetian blinds, and renders with fast speed. A typical city in hot summer and cold zone (HSCW) zone in China - Changsha is taken to demonstrate the evaluation of the annual energy performance of the natural ventilated DSF in this model. The comparative results show that the annual energy demand of the natural ventilated DSF is close to the well thermally insulated fabric. The calculation time is about 51 min under Win 7 system on a standard laptop with 2.90 GHz dual-core CPU.

The effects of horizontal shading device orientation and surface material and the use of a compact silencer in forming acoustical barriers for a ventilated glass double skin facade

Acoustical discomfort due to traffic noise transmission via operable windows is a significant environmental stress for building occupants in urban areas. A ventilated double skin facade, DSF, can potentially address the issue of noise transmission and operable windows. A hypothetically designed glass DSF mock-up was constructed in the opening between the reverberation rooms at the University of Kansas to determine the noise reduction of the DSF mock-up based on the orientation and surface materials of the horizontal shading devices and the use of a compact silencer in place of a typical ventilation grille in the outer skin opening. The compact silencer provides natural ventilation by allowing outside air to flow within the cavity of the DSF. For these laboratory tests, the horizontal shading devices with sound absorbing material were oriented at 0, 30, 60, and 90 degree angles. The laboratory noise reduction measurements are presented for the mock-up with the several shading device orientations and materials and for the use of a compact silencer.

Experimental Study on Opening or Closing Performance of Ventilated Double-Skin Facade on the Airflow Window in Winter

An actual office building with ventilated double-skin facade (VDSF) in cold region has been studied for researching the opening or closing performance of VDSF on the airflow window in winter. In the daytime of winter, airflow window of external facade should be closed, and airflow window of internal facade should be open, according to which the indoor temperature can be kept at a comfortable level effectively, and the purpose of reducing the indoor thermal load and the building energy consumption of air conditioning can be reached. The research also provides the best time of the airflow window of internal facade to open and close. If one directly applies the analysis of experimental results to guide the construction of VDSF and other energy-saving design of buildings, it can provide a reliable reference for similar projects.

A Review of Research Development of Ventilated Double-Skin Facade

Demands for the building energy conservation, thermal and visual comfort make the ventilated double-skin facade (DSF) more attractive and more popular in commercial buildings. This paper reviews the recent research development of ventilated double-skin facade in China. The velocity and temperature distribution in the double-skin facade (DSF) are reviewed, together with the effects of glass types, channel width, intensity of solar radiation and shading methods on the heat transfer of ventilated double-skin facade (DSF). This paper also describes the effect of the different combinations of glass, blinds settings, ventilation rate and the channel width, intensity of solar radiation and shading. Furthermore, the methods to improve the energy saving of ventilated double-skin facade (DSF) are also reviewed.

Construction and Development of a New Ecological Facade

Double skin facade has been popular in China since new century. It provides challenges to deal with overheating problems in air cavity and improve energy saving effects in hot summer and cold winter climate zone in China. This paper develops a new ecological facade which includes three key elements: a ventilated double skin facade, a tillandsia usneoides plant curtain and watering. The biological characteristics especially the absorbtivity of tillandsia usneoides were analyzed via SEM scanning photographs. Bud scales and mesophyll cells of tillandsia usneoides are the main tissues to keep water. Then a method to construct an ecological double skin facade using condensation water was introduced.

A Summer Case Study on Applying Ventilated Double-Skin Facade to a Building in Cold Zone of China

It is crucial for ventilated double-skin facade (DSF) compared to single- skin facade to avoid high energy consumption, optic pollution and inadequate ventilation problems. In this paper, the performance of ventilated DSF applied to a building located in a university in cold zone (Tianjin) of China is tested. The original conditions of both outdoor and indoor within each testing room are comparatively same.The temperature behaviors of both the ventilated air cavity of DSF and indoor space with different experimental modes during summer are investigated. Additionally, the effects on indoor temperature due to the ventilated DSF with different modes in summer are also analyzed. The results shows that the ventilated DSF is a effective approach to reduce indoor temperature; the opening airflow windows of external façade of the DSF should be effective to lower temperature of both the ventilated air cavity of DSF and indoor space.

Simulation of ventilated facades in hot and humid climates

The Hong Kong climate is sub-tropical with hot and humid weather from May to September and temperate climate for the remaining 7 months period. A mechanical ventilation and air-conditioning (MVAC) system is usually operated to avoid the high temperatures resulting in high peak cooling loads. The facade design has a significant influence on the energy performance of office buildings. This work evaluates different ventilated facade designs in respect to energy savings. Thermal building simulations (TRNSYS) were linked to nodal airflow network simulations (COMIS) for detailed ventilated double-skin facade performance. In order to validate the model, simulations were carried out for an office building in Lisboa; the results were compared with measured data from the same building. The simulation results of surface and air temperatures show good agreement with the measurements. The results of the study can be used to reduce surface temperatures by using different materials for the roller blind that is positioned in the cavity of the double-skin facade. The results can further be used to reduce the high peak cooling loads during the summer period. This may result in significant energy savings and a reduction in the system's cooling capacity. It proved that a careful facade design can play an important role in highly glazed buildings and provides potential for energy efficiency.