Comparison of control strategies of venetian blinds regarding visual and thermal comfort in summer in classrooms

Automated external venetian blinds are often used for sun protection in classrooms. This study considers different control strategies for this application in summer season. The strategies are analysed regarding their impact on visual and thermal comfort such as heat protection, glare protection and visual contact to the outside. Possible strategies are compiled and specific control schemes are defined for a comparison. A discussion of visual and thermal comfort helps to select certain assessment measures which are required for the comparison. Thermal building simulation is used to calculate the assessment measures using a model of a typical classroom. In order to enlarge the validity of the results to a broader range of classroom models, certain model parameters with particular relevance are varied. This is realised using a Monte Carlo simulation which includes the sampling of random parameters within defined value ranges. Applying this method several hundred different classroom models are used for each control strategy. A comparison of the assessed control strategies helps to identify sensible control strategies which are combined in an optimised control scheme.