Research Outputs

2019 2019 2018 2018 2017 2017 2016 2016 2015 2015 0.0 0.0 0.2 0.2 0.4 0.4 0.6 0.6 0.8 0.8 1.0 1.0
Now showing 1 - 2 of 2
  • Publication
    Towards distributed enthalpy measurement in large-scale air conditioning systems
    (IEEE, 2015)
    Sauter, Thilo 
    ;
    Steiner, Harald 
    ;
    Glatzl, Thomas 
    ;
    Hortschitz, Wilfried 
    ;
    ;
    Air conditioning systems are among the major energy consumers in buildings. Energy-efficient operation of AC systems is an important step towards better energy management in building automation, but requires efficient monitoring of the energy or enthalpy flows within the AC installation, which is currently still difficult because of the lack of appropriate equipment. This paper introduces a distributed data acquisition system for large-scale AC systems based on low-cost flow sensors implemented by means of standard printed circuit board technology and interconnected via a wireless sensor network. A critical issue for the system installation is the placement of the sensors in the air ducts to obtain representative measurements of the air flow. To this end, extensive aerodynamical simulations are carried out to analyze the flow distributions in typical building blocks for air ducts, particularly with respect to turbulences. The simulation results are compared with experimental data from the literature and are shown to be reliable.
      145Scopus© Citations 7
  • Publication
    A Thermal Flow Sensor Based on Printed Circuit Technology in Constant Temperature Mode for Various Fluids
    (MDPI, 2019)
    Glatzl, Thomas 
    ;
    Beigelbeck, Roman 
    ;
    Cerimovic, Samir 
    ;
    Steiner, Harald 
    ;
    ;
    Sauter, Thilo 
    ;
    Treytl, Albert 
    ;
    Keplinger, Franz 
    We present a thermal flow sensor designed for measuring air as well as water flow velocities in heating, ventilation, and air conditioning (HVAC) systems. The sensor is designed to integrate the flow along the entire diameter of the pipe also quantifying the volume flow rate of the streaming fluid where the calorimetric principle in constant temperature operation is utilized as a readout method. In the constant temperature mode, a controller keeps a specific excess temperature between sensing elements at a constant level resulting in a flow dependent heater voltage. To achieve cost-effective sensors, the fabrication of the transducer is fully based on printed circuit board technology allowing low-cost mass production with different form factors. In addition, 2D-FEM simulations were carried out in order to predict the sensor characteristic of envisaged setups. The simulation enables a fast and easy way to evaluate the sensor’s behaviour in different fluids. The results of the FEM simulations are compared to measurements in real environments, proving the credibility of the model.
      452Scopus© Citations 8