预混和旋流燃烧器回火现象高速激光成像研究

Energy supply is one of the primary building blocks of our society. Worldwide, and especially in rapidly developing countries, e.g. China and India, the demands of energy for housing, industry, transportation and communication are constantly increasing [83]. The global energy supply is currently dominated by combustion of fossil fuels. In 2008, 85.1% of the global primary energy supply was produced from the combustion of oil (34.6%), coal (28.4%) and natural gas (22.1%). From the 12.4% of renewable energy sources, 82% (in total 10.2%) was bioenergy based on burning renewable rescources [45]. Recent reports confirm that a dramatic shift towards CO2 neutral energy supply is required to stop the current trend of global warming [135]. Nevertheless, the slow developement of renewable energies over the last decades as well as the absence of large technological advancements in nuclear fusion technology indicate that this structure will not substantially change in the coming decades. Besides emissions of CO2, further pollutants are formed during the combustion of fossil or biofuels. From these emissions, nitric oxides (NOx) have been identified as a major problem of practical combustion processes [214]. In the recent decades nitric oxides became a significant contributor to photochemical smog and ozone in urban air [180]. It further participates in the chain reaction removing ozone form the stratosphere with the consequence of increased ultraviolet radiation reaching earth’s surface [90]. NOx is generally formed during the oxidation process of nitrogen containing fuels such as coal and oil. However, the gross NOx emissions are created at high combustion temperatures from nitrogen in the air. These are typical for hard coal plants, internal combustion engines and gas turbines. Hence, it is essential to understand the physico-chemical processes of NOx formation and concepts to reduce or even eliminate NOx emissions.