RT Journal Article ID 4e91e3de701860d0 A1 Zama, Yoshio A1 Ochiai, Wataru A1 Sugawara, Kazuma A1 Furuhata, Tomohiko A1 Arai, Masataka T1 STUDY ON MIXING PROCESS OF DIESEL SPRAY UNDER HIGH AMBIENT GAS DENSITY CONDITION JF Atomization and Sprays JO AAS YR 2013 FD 2013-07-25 VO 23 IS 5 SP 443 OP 461 K1 diesel spray K1 ambient gas density K1 velocity distribution K1 equivalence ratio K1 PIV AB In the up-to-date diesel engine, boost pressure has been increased to improve the thermal efficiency as compared with a conventional diesel engine. High boost pressure results in a high gas density condition in the combustion chamber. Therefore, the mixing process of a diesel spray under high ambient gas density conditions may be different from that of a conventional diesel engine. In this study, particle image velocimetry (PIV) was applied to measurement of the velocity field inside a diesel spray under a high ambient gas density condition. From the results of PIV measurements, the maximum velocity gradient positions inside a spray were evaluated, and the effect of ambient gas density on the maximum velocity gradient position was investigated. It was found that the maximum velocity gradient position relative to the spray periphery shifted from the spray periphery to the center of the spray with increasing ambient gas density. A local equivalence ratio distribution inside the spray was calculated in accordance with momentum conservation and the spray velocity obtained with PIV. It was found that the region with sufficient air for combustion shifted upstream with increasing ambient gas density. PB Begell House LK https://www.dl.begellhouse.com/journals/6a7c7e10642258cc,67b312a93f7dc969,4e91e3de701860d0.html