Der Einfluss von turbulenten Skalen und Intensitäten auf die Filtereffizienz von Aerosolpartikeln mit Raumluftreinigern
Zusammenfassung der Projektergebnisse
The study highlights the influence of fan configurations, particle counter positions, and air cleaner flow rates on the air exchange rate (kexp) and turbulent kinetic energy (TKE) within both small and large rooms. Results indicate that fan operation increases kexp across all configurations, although the extent of this effect varies based on spatial positioning and turbulence levels. In the smaller room, kexp decreases with added turbulence, whereas in the larger room, turbulence enhances air exchange. This suggests that room size and airflow patterns play a crucial role in determining ventilation efficiency. Additionally, measurements at different particle counter positions confirm that while local variations exist, the overall trends in kexp remain consistent across reference cases and different fan setups. The TKE analysis further reveals that fan configurations significantly impact turbulence distribution, with configurations A1, A2, and B1 showing the highest turbulence levels at the room’s center. Near-wall turbulence, particularly at Sidewall1 and Sidewall2, is influenced by airflow interactions, with Cam3 consistently registering higher TKE values. The C configuration, characterized by its swirl flow, exhibits distinct turbulence behavior. These findings emphasize the effect of fan placement and orientation in optimizing air mixing and aerosol dispersion. By strategically positioning fans and adjusting turbulence levels, it is possible to enhance air exchange rates and improve indoor air quality, particularly in controlled environments where ventilation is a critical factor. However, the effect is not very large, so that an artificial improvement of the mixing by using fans is not recommended, as this increases energy consumption. However, even taking into account the noise caused by the fans and the less comfortable situation in the room due to the turbulent flow movement, the operation of fans to generate turbulence is not recommended. On the other hand, it can be concluded from the results that increasing the turbulent mixing by breathing or the movement of people does not have a negative effect on the filter efficiency, which is another important result of the study.
