• DE | EN
Menu
Kurztitel: SPEE
Ausführende Stelle: Technische Universität Dresden - Fakultät Maschinenwesen - Institut für Energietechnik - Professur für Gebäudeenergietechnik und Wärmeversorgung
Förderinitiative: Energieoptimiertes Bauen (EnOB)
Laufzeit: 01/2016 bis 06/2018
Bewilligte Summe: 406.436 €
Förderkennzeichen: 03ET1361A
Topics: Modelling & simulation, Heating, ventilation and cooling, Building operation & automation
Innovation: The impact of different sensor positions in rooms on the energy requirement, thermal comfort and air quality can be determined by combining numerical simulations and measurement-based investigations.
Keywords:

Quintessence

  • The position of sensors in rooms affects the energy requirements for controlled HVAC systems as well as the thermal comfort and air quality
  • This impact is determined by combining numerical simulations and measurements
  • Stationary and transient situations can be investigated and evaluated for different rooms
  • This enables general recommendations to be made for different system topologies, spatial geometries and room situations

How does the sensor arrangement affect the energy requirements for heating and air-conditioning systems? And how can this impact be quantified under differing usage conditions? This research project intends to answer these questions based on coupled system and flow simulations in conjunction with experiments carried out in a climate chamber.

Project context

 The reason being that sensors are cheap nowadays. This is why they are finding increased application in measurement and control systems as well as building automation. Sensor positioning is usually based on practical considerations or personal experience. However, reliable and accurate recommendations for positioning the sensors are still lacking, although it has long been assumed that the placement of the sensors has a significant impact on both energy requirements and spatial comfort. The aim of this research project is to understand how different sensor positions – with a view to typical room situations – affect energy requirements, thermal comfort and air quality.

Climate chamber of ILK Dresden gGmbH, 3D CAD model with air-conditioning system.

Climate chamber of ILK Dresden gGmbH, 3D CAD model with air-conditioning system.

© ILK Dresden gGmbH
The investigation is carried out using a combination of experiments in a climate chamber and coupled simulations of buildings, systems and ambient air flows. The picture shows a model of a simulated office space with two persons, different ventilation systems and selected sensor positions S1 to S5.

The investigation is carried out using a combination of experiments in a climate chamber and coupled simulations of buildings, systems and ambient air flows. The picture shows a model of a simulated office space with two persons, different ventilation systems and selected sensor positions S1 to S5.

© TU Dresden
Climate chamber of ILK Dresden gGmbH, photo of the climate chamber with air-conditioning system.

Climate chamber of ILK Dresden gGmbH, photo of the climate chamber with air-conditioning system.

© ILK Dresden gGmbH
Sensor array for temperature measurement in the climate chamber of ILK Dresden gGmbH.

Sensor array for temperature measurement in the climate chamber of ILK Dresden gGmbH.

© ILK Dresden gGmbH
Velocity determination using Particle Image Velocimetry (PIV) in the climate chamber.

Velocity determination using Particle Image Velocimetry (PIV) in the climate chamber.

© ILK Dresden gGmbH
Reproduction of the climate chamber by means of coupled simulations of buildings, systems and ambient air flows (internal surface temperatures).

Reproduction of the climate chamber by means of coupled simulations of buildings, systems and ambient air flows (internal surface temperatures).

© TU Dresden

Research focus

The investigation is conducted using a combination of experiments in a climate chamber, located at the Institute of Air Handling and Refrigeration (ILK) Dresden, and coupled simulations of buildings, systems and room air flows at TU Dresden. The impact of sensor positioning on the energy requirements of the heating and air-conditioning systems is studied for the climate chamber as a reference space, and for other typical office situations. The simulation models are calibrated with data gained from experiments. It is thereby possible to determine the impact of sensor positioning on indoor environmental conditions and energy requirements. Identical situations are compared by means of simulations in office spaces that differ only in their sensor positioning. In using a coupled simulation, the information chain "Sensor – System – Spatial Constructions – Ambient Air Flow" becomes a closed one. Persons are also taken into account in the analysis.

Measured temperatures (below) and calculated temperatures (above) in a decay test with free convection.

Measured temperatures (below) and calculated temperatures (above) in a decay test with free convection.

© ILK Dresden und TU Dresden
Comparison of the energy saving options offered by various ventilation, heating and cooling concepts by varying the sensor position for a 24-hour period and a 2-person office.

Comparison of the energy saving options offered by various ventilation, heating and cooling concepts by varying the sensor position for a 24-hour period and a 2-person office.

© TU Dresden
Office space with eight people, different ventilation systems and examined sensor positions.

Office space with eight people, different ventilation systems and examined sensor positions.

© TU Dresden

Successes

With the measurements combined with the numerical simulations, important facts concerning the influence of the positioning of temperature sensors for steady and moderately transient situations were compiled and first recommendations for the best possible placement of the sensors were developed.

The validation of the numerical simulation on the basis of measurements in the climate chamber was an important intermediate step. This is required for further investigations, because only selected cases are reproduced both in measurement and simulation. The investigations – carried out mostly on the basis of numerical simulations – of the behaviour of different physical, system-technical, structural-physical and geometrical variations of office spaces from an energy-related point of view and from the viewpoint of thermal comfort permitted a comprehensive systems comparison and the formulation of further, general recommendations for action.

The first results demonstrate that sensor positioning offers a great potential for energy savings under certain conditions. In a next step, highly transient situations are examined, for example as caused by intermittent use and changes in user requirements or of the load situation as a result of variable heat gains and losses.

Differences in the daily energy demand of three selected examination configurations as a function of different sensor positions while maintaining thermal comfort.

Differences in the daily energy demand of three selected examination configurations as a function of different sensor positions while maintaining thermal comfort.

© TU Dresden
Surface temperatures for one selected heating case of the multi-person office.

Surface temperatures for one selected heating case of the multi-person office.

© TU Dresden

Application

With the recommendations for sensor positioning, planners and installers are to be aided in their selection of the optimal spatial positioning of the sensors given a certain energy requirement while securing thermal comfort. In addition, consequences and compensation possibilities are identified should optimal sensor positioning not be possible.

Information on this subject will become available as the project continues.

Last Update: 11. April 2017

Related Projects

This website uses cookies to improve our service. For usage analysis we use Matomo. By further using this site you agree to this use. If you don't want to give your consent or you want to learn more about cookies see our privacy policy .

OK