Study Of Effect Of Bio-Additive On Gasoline Engine Performance And Its Reaction Mechanism

With oil price rising, global warming and other environmental problems become more and more seriousy. In order to save energy and protect environment the automotive industry has developed many ways, such as optimizing vehicle structures and reformulating fuel properties. Using additive is one of the methods to reconstruct oil. However, traditional additives are harmful to human beings and engine components. Therefore, it is imperative to find out a green and efficient additive under this situation. Vegetable oil used as fuel for diesel engines is well known, however, it seems to be a new idea to be used as additive in fuel for gasoline engines. Combined with chemical analysis and photochemical research method, this desertation presents the mechanism of how the additive saves energy and reduces emission from the point of view of combustion.The main effect of this bio-additive is to improve the fuel economy and emission performance. Load characteristics in urban road conditions were compared on bench tests in order to compare the performances before and after adding additive under different loads. At the same time, the fuel economy was measured at road condition, as well as exhaust emissions like CO2, CO, HC and NOX under idle condition. Results show that this bio-additive can remarkablly improve fuel economy and reduce exhaust emissions, furthermore, it is compatible to all kinds of gasoline fuel currently used on Chinese market.Based on the indicator diagrams obtained, the maximum pressure in cylinder and heat release rate after adding additive were analyzed. The results show that the additive can increase heat release rate and the maximum pressure in cylinder, which means this additive can promote combustion in cylinder.A constant volume combustion bomb for experiment was designed and manufactured to study premixed flame. The desertation introduces the design procedure and configuration of the bomb, which includes the mixture gas preparation, heating, ignition, combustion pressure measurement systems, CCD camera and data aquisition system. According to the comparison of flame photos, we can reach a conclusion that the combustion speed is faster and the combustion duration period is shorter after adding additive, which means that, as the equipment was not adjusted, additive can improve fuel combustion, shorten combustion duration period and make...