Experiment Study Of Non-thermal Plasma Purifier To Reduce Contaminative Exhaust Of The Gasoline Engine

Rapid development of the automobile industry has led the rapid economic development, but also inevitably caused the serious pollution to the environment. The vehicle emission regulations are being strieter today, so controlling vehicle emissions has become the extremely urgent duty. Technology of tri-catalysis which is wide-spread used presently plays an important role in controlling automobile exhaust, but the costly metals which are used to make tri-catalysis device are limited and discarded tri-catalysis device will bring second-pollution to environment. Thus, finding out the substitutes is becoming the research focus in the world. Technology which is utilizing non-thermal plasma engendered by high voltage pulse to purify contaminative exhaust of gasoline engine provides a new way of thinking and method.Firstly, the mechanism of non-thermal plasma engendered by high voltage pulse is researched by studying the basic theory of discharge in this thesis, then the process of effective compositions such as O3, O, OH and so on making chemical reaction with the main contaminative gases such as NOX, CO and HC is studied. Finally, the mechanism of non-thermal plasma purifying contaminative gases of engine is made clear, which establishes a theoretical foundation for non-thermal plasma purifying contaminative gases of engine. Subsequently, according to analysis of structure of kinds of existing plasma purifiers and actual condition, we design a high voltage pulse non-thermal plasma purifier. In the process of designing power, we mainly consult voltage-shape, parameter and scheme of power which are frequently used to give birth to non-thermal plasma for purifying contaminative gases and unify the plasma purifier and the actual condition, finally the plan of interval-switch high voltage and pulse power system is adopted.To obtain the most suitable parameters match, simulative experiments of standard gases are done in normal temperature and atmospheric pressure. Through analyzing of experiment results, we obtain the most suitable parameters match for the high voltage and pulse power in purifying contaminative exhaust of engine.In the foundation, for testing purification effect of plasma purifier disposing of contaminative gases of engine, pedestal experiment of engine is done in Chongqing university engine laboratory. That plasma purifier could get good effect in disposing contaminative exhaust is proved. At the same times, the rules of purification effect with engine's work condition are finding. Lastly, exhaust experiment of whole vehicle is done in environment examination laboratory of Chang'an corporation, the results furtherly illustrate that plasma purifier could get good effect in disposing contaminative exhaust.