Master's Thesis Marco Bertinelli

 

Development and validation of heating and ventilation- components for dynamic simulation of the energy demand fromresidental buildings

Against the background of an ambitious climate protection target and the efficiency use of
energy in Germany, the energy consumption of residential buildings are subject to many
research projects. The majority of energy consumption in the household sector is accounted
for providing heating, which in particular depends on the construction design and heating
system. Comprehensive buildings can reduce the transmission heat losses by isulation of the
external walls. This development increases the importances of ventilation heat losses. Against
this background model components of the ventilation and heating systems are developed to
investigate the heat requirement by a dynamic simulation. In particular 1) the development
of a realistic model of room air, 2) the heat recovery system and 3) themodeling of local heat
losses caused by window ventilation is brought into focus of this investigation. For this purpose
the developed simulation model is validated by measurements of room temperature. The
validation show that the developed moldes are qualified to illustrate the ambient air in combination
with window ventilation and a user model in a satisfactorily way. The developed model
also allows to take pollutants, and humidity in addition to the temperature into account. Thus,
the level of detail of the simulation and the associated power can be increased considerably.
Two renovation concepts for comprehensive buildings have been simulated to analyze the the
sensitivity of ventilation heat loss on the heating requirement. At this the presence of the user
is identified as the crucial impact parameter. The developed models allow also to figure out
the pollutants and humidity in addition to the room temperature. Thus, the level of detail of
the simulation and the associated power can be increased significantly. Based on this two real
renovation-concepts are simulated to investigate the importance of the detailed consideration
of the ventilation heat losses. The results show that in case of detailed ventilation models
the heating demands always exceed the consumption based on an constant air exchange
rate. Especially the window ventilation losses cause the dynamics of the heat demand. The
energetic evaluation of the systems indicates that the user behavior is able to increase the
primary energy demand by up to 15 percent, as well as reduce the coefficent of performance
of the heat pump system. The evaluation also underlines that using a heat recovery system
can reduce the ventilation losses up to 50 percent.