Large Eddy Simulation を用いたディーゼル噴霧微細構造の数値解析

摘要

燃料噴霧（ディーゼル噴霧）の混合気形成過程はディーrnゼル機関の燃焼特性に影響を及ぼし，機関性能及び排出rnガス特性を左右する重要な因子である．近年では，コモrnンレール噴射装置により噴射圧力，噴射タイミング，噴rn射回数が自由に制御でき，さらには，混合気内の不均一rn性を用いた燃焼改善手法が提案されている．%The paper presents LES approach with KIVA-LES to predict the micro structure in diesel fuel spray, which is not able to simulate in conventional RANS approach with KIVA. Except for the turbulent model, the computational methods for LES approach are almost same as the ones for RANS approach, but several improvements should be performed to simulating the micro structure in a diesel fuel spray such as the computational grid size, convective schemes and spray model used. Furthermore, the visualization techniques are presented to identify the vortex structure predicted in LES approach.