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Two kinds of optical methods for the measurement of the temperature and concentration distribution in combustion chambers by means of the real-time laser holographic interferometry are presented in this paper, which are respectively the one-wavelength laser holographic interferometric technique and the two-wavelength laser holographic interferometric technique. The basic measurement principles of these laser holographic interferometric techniques, the characteristic features of their optical arrangements, the experimental device and testing procedure, and the formula of evaluation of holographic interferograms are described in detail.

The film-space atomization combustion has been implemented in a direct injection, no inlet swirl and shallow ω type combustion chamber and a new combustion system, namely, the ω7 film-space atomization combustion system, has been developed which has been substituted for the traditional space atomization combustion system in a 6E150C diesel engine. As a result, the performance of this engine has been improved substantially. The thickness and its variation process of the fuel film spread on the combustion chamber wall of the piston crown have been measured in a normal operating engine equipped with the ω7 system at different conditions by means of a set of apparatus. The experimental results show that the fuel film area and volume can be automatically adjusted as the engine load changes, which, it is believed, makes the ω7 system attain both the lower specific fuel consumption and the lower peak pressure at all load and speed ranges.

A multi-zone mathematical model of film-space atomization combustion in direct injection diesel engines is presented, which consists of a submodel of evaporation and combustion of the fuel film sprayed on the combustion chamber wall and a submodel of atomization combustion of the fuel sprayed in combustion chamber space. The fuel film sprayed on the combustion chamber wall is divided into many subzones and the fuel sprayed in the combustion chamber space is considered as one subzone. The submodels are combined through the conservation of the energy and mass in the full film-space atomization combustion system, and an overall system of differential equations are given. The initial and boundary conditions are resulted from the experiments on diesel engines. By means of the model, the film-space atomization combustion processes in 6E150 diesel engine are investigated quantitatively. The comparison between the calculated results of the model and the experimental data is satisfactory.