Search Results

To clarify the detailed structure of high pressure fuel spray, 2-D sectional images of non-evaporating fuel sprays in a high pressure vessel were observed by using the laser light sheet of a copper vapor laser. By this system, many sectional and continuous photographs of the same spray were obtained, and were very effective for the detailed observation of the spray inner structure and its developing process. The spray inner structure was very complicated, and its fuel density distribution was very heterogeneous. And for its developing process, the spray advances straight immediately after injected, then meanders, and deforms into a branch-like structure. Advancing downstream, these branches distribute complicatedly and heterogeneously with low density droplets. The heterogeneity is owing to these branches. And, the developing process is divided into four regions. Further, the effects of some parameters on this process were investigated.

In our first study[1], we reported that the self-regeneration of DPF is enabled by the function of residual potassium methoxide (CH3OK) as catalyst, contained in biodiesel fuel that is collected in the DPF at lower engine loads[1]. In the present report, exhaust emission characteristics after using DPF were investigated by continuous measurement of exhaust gas. The results show that the self-regeneration of DPF occurs when engine loads change from lower to higher, and at the same time, methanol concentration in exhaust gas reaches to a higher peak. This peak is higher than when self-regeneration does not take place. The higher concentration of methanol is reduced by repeating the self-regeneration. The SOF content in PM is reduced by DPF at both high and low engine load, which is a characteristic that was not seen with gas oil.