Development of Spray and Combustion Method for Low Environmental Load by Fuel Design Approach

研究了双组分燃油喷雾在定容容器中的点火特性。实验结果表明，即使加入大量的低可燃性燃料，高可燃性燃料的点火特性仍占主导地位。此外，我们得出结论，点火的增强是由于高可燃性燃料引起的低温氧化反应放热量的增加。在本实验条件下，由大量低可燃性燃料组成的混合燃料的可燃性被十六烷数高于正癸烷数的燃料所提高。此外，我们还研究了两种混合燃料在低温和高温氧化反应下化学物质的空间分布。一种（燃料A）由高可燃性和低可燃性燃料组成，它们的沸点相似。另一种（燃料B）也包括高可燃性和低可燃性燃料，但高可燃性燃料的波动性更低，低可燃性燃料的波动性更高。在低温反应中，当当量比较高时，在液长附近观察到前者的自然火焰发射。另一方面，后者的化学发光在下游的燃油喷雾中被捕获。高沸点燃料与高沸点燃料混合时，低沸点燃料的挥发性虽因两相区形成的低沸点原因而提高，但低沸点燃料比高沸点燃料蒸发得早，这抑制了高可燃性燃料在近液长处的反应。相反，在高温反应中，燃料B的喷射比燃料a的喷射高，这是上述高沸点燃料两相区形成和蒸发增强的证据。因此，高可燃性燃料积聚在喷雾上部区域引发了高温反应。实验分析表明，混合燃料具有高可燃性和高挥发性的特点，是未来燃料应用的一种方法。少

Ignition characteristics of two-component fuel spray were investigated in constant volume vessel. The result drawn from present experiment is that ignition characteristics were dominated by higher ignitability fuel even if much amount of lower one was blended. Furthermore, we concluded that the enhancement of ignition was derived from increase of amount of exothermic heat under low temperature oxidation reaction caused by higher ignitability fuel. In this experimental condition, ignitability of mixed fuel, which consists of much amount of low ignitability fuel, was enhanced by the fuel which has higher cetane number than that of n-Decane.In addition, we investigated the spatial distribution of chemical species regarding two types of mixed fuels under low and high temperature oxidation reaction. One (fuel A) consists of high and low ignitability fuels and these have similar boiling point. And the other (fuel B) also consists of high and low ignitability fuels, but high ignitability fuel … More has lower volatility and low one has higher volatility. In the case of low temperature reaction, natural flame emission of the former was observed near liquid length where equivalence ratio is high. On the other hand, chemiluminescence of the latter was captured further downstream in fuel spray. Although the volatility of higher boiling point fuel is improved by lower one cause of formation of two-phase region if they are mixed, lower one evaporates earlier than higher one and that inhibits the reaction of high ignitability fuel near liquid length. In contrast, in the case of high temperature reaction, the emission of fuel B was observed upper region in fuel spray than that of fuel A. Consequently, this is the evidence for formation of two-phase region and enhancement of evaporation of high boiling point fuel mentioned above. Thus, the high ignitability fuel accumulated in upper region inside spay initiated the high temperature reaction.Our experimental analysis shows that mixed fuel has a potential to combine high ignitability and volatility characteristics and applies the future application method about fuels. Less