Optimisation of wasted air utilisation in thermal loss reduction in double-glazed windows of commercial buildings in cold regions

Abstract

Ventilating of multi pane-glazed windows using wasted air of buildings is an effective technique to minimize heat loss through windows and save heating energy in cold regions. In low-scaled occupancy buildings with high WWR ratio, buildings supply a low flow rate of wasted air to windows ventilation systems, resulting in a declination in its thermal performance. Therefore, this study introduces methods of managing the utilisation of wasted air in windows ventilation to optimise the energy saving. Two methods have been implemented experimentally on a small-scaled room. The first method is a time-based division of air pump operation, an air pump ventilates multiple windows, one window at a time repetitively. The second method shares the available wasted air to multiple windows. The experimental results and mathematical heat transfer model have been employed to evaluate thermal performance of the system in different methods. The first method showed a best energy saving with a duty cycle of 50% for the air pump, and on/off operation every 10 s. An energy saving of 42.6% has been realized compared to the traditional double-glazed windows, and the heat transfer coefficient was declined from 3.82 to 2.8 W/m2 K. The second method showed an optimum thermal performance when the available flow rate of wasted air was shared with three double-glazed windows. An energy saving of 83.1% was achieved compared to the traditional double-glazed windows, and the heat transfer coefficient dropped from 3.82 to 2.36 W/m2 K.

Automated quantification system for vision through polymer‐dispersed liquid crystal double‐glazed windows: Circuit implementation

“…The study realised an overall energy saving of 38.2%. A similar methodology was applied by Lami et al [7] to ventilate a double-glazed window in commercial buildings. The ventilation process led to an energy saving of 83.1% and a declination in the heat transfer coefficient of 3.82 to 2.36 W/m2 K compared to the conventional double-glazed windows.…”

Study on the operation strategies and carbon emission of heating systems in the context of building energy conservation

“…19 Sun et al 20 proposed transparent insulation as a component material of windows to reduce heat loss and effectively use solar heating, which can decrease building energy consumption by 35.8%. Lami et al 21 recycled the wasted air in windows ventilation to optimize the energy saving. The results showed that an energy saving of 83.1% was achieved when the available flow rate of wasted air was shared with three double-glazed windows.…”