ディーゼル機関の微粒子測定用冷却式小形希釈トンネルの開発とその測定結果

抄録

A freezing dilution mini-tunnel method is described which allows sampling of diesel exhaust particulates with independent control of the diluted gas temperature T_d and collecting mesh surface temperature T_w. Particulates in the diluted gas are caught on the cooled mesh surface kept the low temperature with liquid air at T_w. This tunnel was examined to determine the individual effect of these two operating variables T_d, T_w on the samples collected just behind an exhaust valve of a single-cylinder direct-injection test engine run at constant speed and load. Either decreasing diluted gas temperature or sampling mesh surface temperature resulted in an increase of particulate diameter and coagulation of liquidwise particulates and cohesion of particulates.