| Abstract [eng] |
One of the most important factors for hydronic floor heating system efficiency is heated flow medium. According to the literature analysis it was concluded that pulsed flow can have a substantial effect on the heat transfer coefficient of the heating device. Also, it has been observed that flow velocity is an important factor for the effect created by pulsed flow on the heat transfer effectiveness. When the flow is in laminar or undefined state, the biggest pulsed flow effects can be observed, although when the flow velocity increases, and it becomes turbulent the pulsed flow effect slowly disappears. The study on pulsed flow in hydronic floor heating system was simulated using COMSOL Multiphysics software. The results indicated 5.8 % increase in heat flow rate in the pipe, although the heated floor surface temperature had not increased significantly compared to the steady flow solution. While using the results of the first study, a study on pulsed flow use in hydronic floor heating system in an office building has been conducted using EQUA IDA-ICE software. The biggest difference in energy consumption when comparing pulsed and steady flows was 3 %, when screed thickness was set to 65 mm and heated flow medium temperature to 50 °C. Based on these studies a conclusion has been made that pulsed flow technology is not effective in heating devices that use conduction as the main source of heat transfer. In further research of pulsed medium flow, it is advised to use heating devices that use convection as the main source of heat transfer. |
