研发一种光学诊断技术用于分析高压柴油喷射的混合和自引

Development of Optical Diagnostic Techniques to Correlate Mixing and Auto-Ignition
Processes in High Pressure Diesel Jets A tracer laser-induced fluorescence (LIF) technique for the
visualization of fuel distribution in the presence of oxygen was developed and then used sequentially with
high speed chemiluminescence imaging to study the correlation between the mixing and auto-ignition
processes of high pressure Diesel jets. A single hole common rail Diesel injector allowing high injection
pressures up to 150 MPa was used. The reacting fuel spray was observed in a high pressure, high temperature
cell that reproduces the thermodynamic conditions which exist in the combustion chamber of a
Diesel engine during injection. Both free jet and flat wall impinging jet configurations were studied.
Several tracers were first considered with the objective of developing a tracer-LIF technique in the presence
of oxygen. 5-nonanone was selected for its higher fluorescence efficiency. This technique was subsequently
combined with high speed chemiluminescence imaging to study the correlation between mixing
and auto-ignition. In the free jet configuration and for the parameter range studied, it was found that
auto-ignition is preferentially located in rich regions of the upstream mixing zone. Also, in the jet wall
configuration, auto-ignition appears in the centre of the jet and propagates towards the periphery, in the
vicinity of the wall. 汽车发动机多参量测试系统 德国LaVision PIV/PLIF粒子成像测速场仪 PLIF平面激光诱导荧光火焰燃烧检测系统