In an industrial incinerator, suppression of ash emission is of great importance from a viewpoint of environment preservation. In some of the incinerators, a control plate is equipped to suppress the ashes, where it is designed based on engineers’ experience. The control plate is assumed to recoil the ash particles. On the other hand, effect of the control plate has not been examined sufficiently, and besides behavior of ash particles has not been figured out in the incinerator. This is because the incinerator scale is so large that validation tests cannot be performed. In the present study, a numerical technology is applied to an industrial incinerator to examine the effect of the control plate and to analyze the ash particle behavior. In the numerical simulations modeling of an arbitrary shape wall boundary and large-scale simulation technique are required. In this study, advanced DEM-CFD method is employed, where coarse grain model of the DEM is used as scaling law modeling and signed distance function and immersed boundary method are applied to arbitrary shape wall boundary in the DEM-CFD method. The numerical simulations illustrate that the control plate works effectively, whereas, against all expectations, the ash particles are shown to remain in the incinerator not by collision to wall but by settling on the plate due to vortex.

In order to simulate the atmospheric corrosion of tannic acid-coated steels in industrial and coastal districts, artificial steel rust particles of α- and β-FeOOH were synthesized by aerial oxidation of aqueous Fe²⁺ solutions containing various amounts of tannic acid. Increasing addition amount of tannic acid accelerates the formation of amorphous iron-gallic acid complexes to suppress the generation of FeOOH rust. The crystallization and growth of α-FeOOH particles were inhibited by adding tannic acid, while those of β-FeOOH particles are markedly dependent of addition amount of tannic acid. Accordingly, it can be regarded that the tannic acid eluted from tannic acid-coated steels by atmospheric corrosion strongly affects on the formation of α- and β-FeOOH rust and the effect in coastal area is greater than urban district.

In this paper, results of experiments that authors carried out to investigate soot formation in pulverized coal combustion fields were summarized. Soot particles form at the local spatial and temporal scales. Hence, laser induced incandescence (LII), which has high spatial and temporal resolution, was applied to the measurement of soot volume fraction. Firstly, details of LII in the present study is described. Secondly, soot formation from pulverized coal were measured by LII measurement and simultaneous measurements of Mie scattering and Laser induced fluorescence (LIF). Finally, soot growth, agglomeration, and oxidation processes were investigated through Time-Resolved LII (TiRe-LII).

Photoacoustic (PA) imaging is one of the rapidly growing techniques for biomedical imaging because this noninvasive imaging technique combines the advantages of both optical and acoustic imaging techniques. The degree of contrast in PA imaging depends on the optical-to-acoustic conversion (optoacoustic) efficiency and can be exogenously improved by using nanoparticles (NPs) as contrast agents. With recent progress in nanotechnology, various NPs have been synthesized to serve as contrast agents. These studies focus on the improvement of absorption efficiency of light energy of the particles because the amplitude of PA signal increases with increasing absorption efficiency. Nevertheless, we have limited knowledge of the fundamental aspects of the photoacoustic phenomenon. This review presents our theoretical description of the PA pressure pulse from suspensions of NPs and some experimental results. The findings of our studies and the proposed phenomenological model provide a strategy for the design of NPs for PA contrast imaging.