An Experimental Investigation on the Influence of Temperature on the Normal Impact of Fine Particles with a Plane Surface

This study investigated the rebound behavior of SiO₂ particles normally impacting a planar surface under different temperature conditions. The system has been characterized for an aerosol inlet temperature range of 20–190 °C, flow velocities of 0–20 ms⁻¹, and an impaction surface temperature range of 20–140 °C. For the first time, while keeping the same temperature gradient from the high- to low-temperature regions, the influences of varying temperature on the rebound behavior of SiO₂ particles normally impacting a plane surface were examined. At increased temperatures, the plastic deformation increases and the coefficient of restitution reduces. The critical velocity is between 0.542 and 0.546 m/s under condition 1 (the carrier gas temperature (T_g) and the impaction surface temperature (T_W) remain at room temperature of 20 °C), which increases to between 0.829 and 0.847 m/s under condition 4 (T_g and T_W remain at temperatures of 190 °C and 140 °C, respectively). The experimental results show that the critical velocity increases with increasing temperature.