(in German)

An AmI platform concept (AmI = Ambient Intelligence) was developed based on model and laboratory studies which have analysed the impact of indoor air climate on the skin. This concept is intended to lower the drying of the skin by a smart room climate control system in dry indoor air under winter conditions. The room climate situations in offices have been investigated by applying coupled building, system and flow simulations. Necessary property data were determined with test person experiments in a climate chamber. The outcomes of the three subareas - controller development, air flow simulation and test person experiments - were combined in a joint recommendation for action.

The developed model based smart room climate control makes it possible to "guess" what impact the room climate parameters may have on the occupants. The results of the calculations carried out with the controller show the opportunity of adjusting optimised thermal and hygienic comfortable room climate conditions. The integration of a detailed thermoregulatory model into the controller is an innovation.

The coupled simulations of indoor air flow, building envelope and technical systems include a detailed thermoregulatory model, which allowed the reproduction of the person's reaction (skin dehydration, thermal sensation) on the indoor climate conditions (temperature, humidity, air velocity and intensity of air turbulence). Depending on the type of heating and air supply system, the simulations show different flow conditions in the vicinity of the persons, which more (e.g. mixed ventilation) or less (e.g. displacement ventilation) favour the drying of the skin.

Test person experiments (n = 66) at 8 configuration (t_a = 20°C/24°C, RH = 20 %/40 %, v_a about 0,04 m/s/0,12 m/s) were used to measure the cornerstones of the areas typically observed in the winter heating period. According to this, the type of ventilation has a significant impact on the climate sensation and the evaporation of the skin. The test series showed that air velocity has a more pronounced impact on the evaporation and the subjective perception and evaluation of the room climate than the fluctuation in relative humidity.

A recommendation for action published as an supplementary annex provides information how to optimise room ventilation and how to behave in order to reduce negative effects of the indoor climate on the sensation of employees during the winter heating period.

Please download the complete report "Smart control of air conditioning systems - Model based and laboratory studies on the impact of indoor climate on the skin" (in German only).