HF11-180_Development of a ventilation system for coupled and box- type windows

Initiated with an innovation check, a brandnew window construction with ventilation openings was physically investigated and technically advised. Requirements for the thermal insulation necessitate an increase of the usage of coupled and box-type windows. On the other hand, there are increasingly problems with condensate formation and poor ventilation, which are largely due to overly dense windows and too little ventilation by the users. A solution to the problem could be a ventilation device at the window, which is controllable on the one hand and also addresses the different requirements in summer and winter. Thus, as an idea, a sophisticated ventilation system was developed, which had an air intake at the bottom of the outside, and an air intake on top of the inside, which is adjustable. The interspace also acts as an attenuator for the wind inflow. The comfort and the functional requirements of the submitted prototype were analyzed in detail from the viewpoint of energy saving. The novel window construction with ventilation openings has been tested for the first time under laboratory conditions and freefield conditions. The tests included inter alia, measurements of air permeability, watertighteness, thermal behavior in the HotBox, heat flux calculations, and analyzes of acoustic engineering and fluid dynamics. Thus potential for improvement could be detected as a basis for prospective projects.