Accurate Numerical Study on Spray Atomization Process of VCO Nozzle

2014 Fiscal Year Final Research Report

• Project/Area Number: 24760137
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Fluid engineering
• Research Institution: Saga University (2014); Tottori University (2012-2013)
• Principal Investigator: SUMI Takahiro 佐賀大学, 工学(系)研究科(研究院), 准教授 (30358668)
• Research Collaborator: YAMANE Tomofumi 三菱日立パワーシステムズ株式会社 ; KUROTAKI Takuji 国立研究開発法人宇宙航空研究開発機構, 航空技術部門, 上席研究員 (20358659)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 混相流 / 微粒化 / 数値流体力学

Outline of Final Research Achievements

The VCO (Valve Covered Orifice) nozzle is well known to reduce unburned hydrocarbon emission from direct-injection diesel engines. In the present study, we examine a relation between internal flow in the nozzle hole and spray atomization process in the nozzle chamber by using CFD (Computational Fluid Dynamics). Spray atomization characteristics behind the nozzle exit are greatly affected by swirling flow generated due to needle eccentricity, and is found to be organized by the swirl number calculated in the nozzle hole. Furthermore, toward the analysis of high-pressure fuel spray atomization phenomena in the recent direct-injection diesel engines, we have developed an accurate numerical simulation code for compressible two-phase flows, and obtained problems and prospects related to the future work.

Free Research Field

数値流体力学