エンジン内流動計測を想定したPIV用蛍光トレーサ粒子の作製

摘要

SiO_2微粒子を基にし，エンジン内流れの蛍光PIV計測を想定した蛍光トレーサ粒子の作製を試みた.その結果， 作製した蛍光トレーサ粒子は，本実験の範囲内では蛍光色素量が少ないほどより強く蛍光を発すること，Si0_2微粒 子の場合と概ね同等のPIV計測精度となること，また， アクリル壁面衝突噴流に適用した所，壁面から1mm付近 でも粒子像を確認できる，ことなどを示した.%Flow dynamics near the wall boundary layer of an engine cylinder and the spark plug gap have become more important to reduce cooling losses, or to promote more stable lean or dilute combustion. However, PIV measurement of these flows in engine is difficult because of the flare due to the solid object Therefore, to reduce this undesirable effect, fluorescent particle methods have been proposed, but many of the fluorescent particles available are too expensive to employ and/or combustible because they are organic-materials. In this study, the production of inexpensive inorganic-based fluorescent particles was attempted and the fluorescent particles were applied to PIV measurements of a free jet. In the case of jet impingement on an acrylic wall, the flare from the wall was reduced and the particles near the wail could be detected.