| With the decreasing of petroleum resources, the shortage of energy and environmental pollution has become the biggest problem all over the world.Under such circumstances, It is very important to find a new and renewable energy. Biodiesel is the use of vegetable oils or animal fats refined for industrial fuel combustion, the development of bio energy has opened up a new field of oil demand. Vegetable oil is a compound composed of unsaturated fatty acids and glycerol into combinations, which are widely distributed in nature. Bio-oil is a renewable fuel, which has large density and viscosity, low calorific value, but lower sulfur content.At present, research on the application of bio oil mainly focus on two aspects:direct combustion, biological oil ore reduction agent and the modified production of biodiesel. Therefore, this paper focuses on the research of bio oil and biodiesel furnace behavior, to improve the atomization effect, the improvement of oil burner, combustion mode,which has vital significance to reduce emissions.The experiment of atomization characteristics of bio-oil was carried out in the atomization experiment system which set up by ourselves. Using high-speed camera (PIV) to investigate the influence on the atomization particle diameter, particle velocity, spray angle in different temperatures and different pressure.The results show that:as the pressure increases, spray cone angle of all the six samples becomes larger. Under the pressure conditions of 1.6Mpa,atomizer cone angle of waste oil reaches 46.7°, Jatropha biodiesel reached 51.3°, atomizer cone angle varies with the pressure of a linear relationship. Atomized particle size to the minimum in the axial direction at 10cm, where waste oil’s SMD was 175.4 μm, Jatropha biodiesel is 160.4 μm, bio-oil and bio-diesel particle size change in quadratic equation in the radial direction.The mean diameter(SMD) of atomized particles of bio-oil was about 30μm biger than that of biodiesel;With the change of pressure, the atomization particle diameter showed two linear relationship, and as the pressure becomes larger, the value of diameter decreases; The droplet size number distribution curves of bio-oils were roughly the same,they were all rising to a peak value and then decline, and finally gradually level off. The atomized particle size of Jatropha oil and rubber seed oil is mainly concentrated in 150-250μm, in terms of biodiesel is mainly concentrated in 40-160μm, And the number of the droplet size distribution curve substantially identical, the same as the change trend of bio-oils.Under the condition of 90℃,1.6Mpa, examining the change in radial velocity of atomized particles, atomized droplets radial velocity gradually decreases from the inside to the outside, In the nozzle at the bottom of the speed change is bigger than at the top of the speed change, the speed of change in bio-oil atomized droplets larger than the speed of biodiesel change, indicating one of the major factors affecting viscosity are atomized droplets velocity changes.The experimental method will be affected by external conditions and can not achieve the desired objective. At present, some formulas can be used for the droplet size distribution prediction and assessment. Prediction of droplet size distribution function has two methods:one is the empirical formula, and the other is the theoretical distribution function. In this paper, using the Rosin-Rammler distribution function to describe the liquid droplet size distribution,and the MATLAB software to calculate the atomized droplets theoretical distribution function. Analysis and compared with the experimental results, which proves the reliability that using high-speed camera on the atomization experiment.
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