ABSTRACT
Modern engine combustion concepts such as in direct-injection (DI) gaso line and diesel engines benefit from laser diagnostic tools that permit deeper insights into in-cylinder processes such as flow generation, fuel injection and spray formation, atomization and mixing, ignition and combustion, and formation and reduction of pollutants. This chapter presents measurement techniques such as particle imaging velocimetry (PIV) with a frequencydoubled double-pulse Nd:YAG laser and laser Doppler anemometry (LDA) with a flexible optical probe for in-cylinder flow analysis; Mie scat tering on fuel droplets using a copper vapor laser combined with high-speed filming; laser-induced fluorescence (LIF) with an excimer laser for spray and fuel vapor analysis; spontaneous Raman spectroscopy (SRS) for the mea surement of the air/fuel ratio; high-speed filming and tomographic combus tion analysis (TCA) for flame propagation analysis; and laser-induced incandescence (LII) and NO-LIF for the detection of pollutants formed by the combustion process.
