Ventilation of Apartments und Offices

We develop and evaluate comfort oriented and energy efficient ventilation concepts for residential and office buildings. Our focus here is on decentralized ventilation solutions, which are particularly important in the context of the renovation and refurbishment of existing buildings.

For this purpose, air quality, air temperature and air humidity as well as their spatial distribution must be combined with efficient heat recovery concepts and suitable flow control. Energetic aspects are considered as well as the evaluation of indoor air quality with regard to comfort and user behavior.

Based on simulations and experimental characterization, we evaluate the energy demand and the indoor air quality on different scales. This enables us to develop and analyze equipment concepts or subcomponents such as distribution systems or new types of heat exchangers.

Our R&D services include:

• Simulation of ventilation units, indoor air flow and building simulation / development of controls
• Ventilation concepts for existing buildings and façade-integrated HVAC
• Development of innovative ventilation units
• Monitoring of ventilation systems and laboratory measurements

We simulate and model on different levels in order to optimize innovative ventilation units and develop new ventilation concepts. For example, we model the flows at apartment level using the Airflow Network method and calculate volume flows between rooms, energy consumption, heating and cooling loads, comfort and air exchange rates. User behavior, such as presence, window opening, CO2 and moisture loads, is also included in our modeling considerations. This enables us to evaluate, optimize and further develop innovative controls for ventilation units.

By means of Computational Fluid Dynamics (CFD) we investigate the flow behavior in the ventilation unit. CFD simulation at device level enables devices to be fluidically optimized in the early development phase. In this way, pressure losses, velocities, dead volumes and control can be determined and optimized at an early stage.

Indoor air flows are also investigated using CFD flow simulation. This results in a holistic approach to the ventilation of apartments.

We develop innovative ventilation concepts that can be easily and cost-effectively integrated into the façade during the renovation or refurbishment of buildings. In addition to façade-integrated ventilation ducts, central apartment ventilation units are used here. The energy requirements and CO2 emissions of buildings retrofitted in this way can be significantly reduced.

In addition to the development, optimization and evaluation of decentralized, façade-integrated ventilation units and domestic ventilation units, we are also investigating the integration of heating, ventilation and electronic components in building façades.

Together with project partners from industry, we develop innovative domestic ventilation devices. We also carry out monitoring of ventilation systems and laboratory measurements in our Center for Heating and Cooling Technologies.

The patented domestic ventilation unit SWIRL, for example, is a unit with a rotary heat exchanger in which each room has its own small fan with speed control. In this way, it is possible to regulate precisely the requirements (CO2, humidity, VOCs, etc.) in every room.

We evaluate ventilation systems and room comfort both in our laboratories and in field tests in residential and office buildings. We consider energy aspects and various indicators of hygrothermal comfort (temperature, humidity, CO2, VOCs), comfort, ventilation efficiency and their spatial distribution. User behavior, e.g. opening windows and doors, is also included in the study.

In our Center for Heating and Cooling Technologies we evaluate and measure components as well as decentralized and centralized ventilation devices and optimize them e.g. with regard to temperature, humidity, heat recovery, pressure loss, volume flow/mass flow and dehumidification and humidification.