3219 レーザ2焦点流速計によるディーゼル燃料噴射ノズル噴孔近傍の液滴粒径分布計測(S48-1 燃料噴霧・混合気形成(1),S48 燃料噴霧・混合気形成)

抄録

A laser 2-focus velocimeter (L2F) with a micro-scale probe volume has been developed for the measurements of velocity and size of droplets in a dense spray. Diesel fuel spray injected from a hole of a diameter of 0.2mm in the atmosphere was measured by the L2F at 1.5mm downstream from the nozzle exit. Measurements of injection pressure, needle lift, and crank angle were synchronized with the L2F measurements. The measurement result shows that the droplet size increases with the needle valve rising and little changes after the needle valve is fully opening. It is found that the droplet size distribution in the spray core region can be fitted to the Nukiyama-Tanasawa's distrbution in the period of rising and fully opening of the needle valve.