Detection On Combustion Characteristic, Temperature And Soot Concentration Of Ethylene-Oxygen Enriched Flame

Oxygen-enriched Combustion Technology is a high efficiency and low pollutioncombustion technology, with the advantages of burning completely, reducing the amount offlue gas and saving raw materials. However, as the increasing of the concentration ofoxygen, the basic combustion characteristic of the flame and the parameters of temperatureand concentration of soot will change correspondingly. To utilize the Oxygen-enrichedCombustion Technology more effectively, it is of great significance to research the propertychanges of the oxygen-enriched combustion flame and the distributions of the temperatureand soot concentration. In this thesis, image detection system and visible spectroscopymeasurement system are used to do experimental research on ethylene oxygen-enricheddiffusion flame. The details are as follows:The ethylene oxygen-enriched diffusion flame experiment system is designed andestablished. The experiment is conducted by using the image detection system. Based onthe results of the experiment and the theoretical analysis, the main conclusions are asfollows: under the oxygen-enriched air atmosphere, the length of the flame get shorter, theflame color change to brilliant white and the luminance field decreases and contracts to theburner nozzle gradually with the oxygen concentration; under the oxygen-enriched O₂/CO₂atmosphere, with the increase of the concentration of oxygen, the wholly change trend ofthe flame is familiar with that of oxygen-enriched air atmosphere, while the flame appearsjetter horizontally and extinct easily.Using the visible spectroscopy measurement system, we measure the spectrumradiative sign distributions of different length of different flame of ethylene with30%oxygen,40%oxygen,50%oxygen and100%oxygen separately, under oxygen-enriched airatmosphere. Revise the intensity distribution with the calibration factor based on theblackbody furnace, and then calculate the distribution of temperature and concentration ofsoot through the regularized reconstruction algorithm. The results show that, with theincrease of the concentration of oxygen, the temperature of the flame increases, themaximum value of the flame moves up to the top of the flame. When the concentration of oxygen increases to50%, the concentration of soot increases too. However, theconcentration of soot is much lower in pure oxygen atmosphere then that in air atmosphere.