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It is very much necessary for researchers and engineers whose work is the field of combustion in a CI engine to find the information of droplets in a diesel spray. The information is strongly required to construct the model of spray built in the numerical code for its simulation and to be used for the verification of the accuracy of the calculation. This paper describes the photographing system with high spatial resolution, the distribution of droplet size and the vortex scale caused by the droplets motion by means of this system.

The maximum liquid-phase penetration and vaporization behavior was investigated by using simultaneous measurement for mie-scattered light images and shadowgraph ones. The objective of this study was to analyze effect of variant parameters (injection pressure, ambient gas condition and fuel temperature) and fuel properties on vaporization behavior, and to investigate liquid phase penetration for the single- and multi-component fuels. The experiments were conducted in a constant-volume vessel with optical access. Fuel was injected into the vessel with electronically controlled common rail injector.

This work investigates the soot formation process in diesel jet flame using a detailed kinetic soot model implemented into the KIVA-3V multidimensional CFD code and 2D imaging by use of time-resolved laser induced incandescence (LII). The numerical model is based on the KIVA code which is modified to use CHEMKIN as the chemistry solver using Message Passing Interface (MPI). This allows for the chemical reactions to be simulated in parallel on multiple CPUs. The detailed soot model used is based on the method of moments, which begins with fuel pyrolysis, followed by the formation of polycyclic aromatic hydrocarbons, their growth and coagulation into spherical particles, and finally, surface growth and oxidation of the particles. The model can describe the spatial and temporal characteristics of soot formation processes such as soot precursors distributions, nucleation rate and surface reaction rate.

This paper describes the soot behavior in a diesel flame. The experiments were carried out in a constant volume chamber with quiescent atmosphere. Parameters were the ambient temperature and the oxygen concentration. The integrated image of flame was taken, the natural emission of flame was detected and the KL factor was found by means of classical technique of laser light extinction. The results were discussed by use of the apparent rate of heat release. As a result, the ignition delay and the vortex with large scale generated in a diesel spray affect the soot behavior in a diesel flame.

The atomization structure of the fuel spray is known to be affected by flow conditions and cavitation inside the nozzle hole. In this paper, the cavitation phenomena inside the nozzle hole was visualized by using large-scale transparent nozzles, as well as the effect of length-to-width ratio (l/w ratio) of the nozzle hole on cavitation and on the behavior of injection liquid jet. In addition, various flow patterns inside the nozzle hole same as experimental conditions were simulated by the use of Cavitation model incorporated in Star-CCM+, which was compared with experimental results.