Our laboratory developed the laser image measurement system called the two-wavelength laser absorption scattering (LAS) system, which enables the determination of the particle size in sprays that are being evaporated in the combustion chamber or the reactor, concentration distribution of steam phase and liquid phase, and the mixing status with atmospherics (air) at the time.
The LAS method uses a pulse laser with two ultraviolet and visible wavelengths, parallel-pencil optical system and two CCD cameras for the measurement system, and fuels that have an absorption band in the ultraviolet wavelength for testing fuels. Liquid phase concentration distribution is obtained from visible-light images, and concentration distribution of steam phase is obtained from images of the difference between the ultraviolet-light images and the visible-light images.
The present measurement system is innovative in terms of the fact that the concentration distribution of the steam phase and liquid phase that could not be obtained through conventional image measurement systems can be obtained quantitatively. When the LAS method is incorporated in the development of products such as internal combustion engines, atomization combustion systems that handle evaporated atomization, characteristics of evaporation and atomization, which has so far been a black box, are clarified.