| Authors |
Masionis, Justinas ; Čiužas, Darius ; Krugly, Edvinas ; Tichonovas, Martynas ; Prasauskas, Tadas ; Kukelkaitė, Justina ; Martuzevičius, Dainius |
| Abstract [eng] |
Ensuring the effective removal of airborne particles is essential for maintaining indoor air quality, particularly in environments with limited ventilation. This study examines how ion polarity regime, voltage, and relative humidity influence aerosol particle removal in a controlled, room-sized chamber (35.8 m3) using a custom-built air ionizer. Experiments were conducted under stagnant and ventilated conditions (0.5 h−1) while varying ionizer polarity (positive, negative, bipolar, alternating), voltage (6 kV, 10 kV), humidity (40%, 70%), and aerosol type (incense smoke, nebulized KCl). Positive and negative unipolar ionization achieved over 90% removal within 60 min, with decay rates of 0.04–0.05 min−1, half-lives of 13–17 min, and clean air delivery rates (CADR) of 60–90 m3 h−1. Bipolar ionization was less efficient due to ion-ion recombination, yielding CADR values below 25 m3 h−1, while alternating polarity improved deposition (40–70 m3 h−1) by reducing recombination losses. Relative humidity had a minimal influence on unipolar performance but moderated efficiency in bipolar and alternating modes. Under low ventilation, unipolar negative ionization sustained high removal (96.7%), while ozone remained below the detection limits of the methods used. These findings indicate that ion polarity control and field strength strongly influence particle removal and that unipolar or alternating-polarity operation can provide effective particle removal under controlled chamber conditions, including a low-ventilation case of 0.5 h−1. |
