Research On Spray Quality Evaluation Of Biomass Pyrolysis Emulsified Oil Bsed On The Theoretical And Experimental Comparison

With human’s rising demand for fossil fuels, the worldwide’s shortage of oil resources and the environmental pollution has become a huge problem which we have to face. As all we know, the oil storage capacity on Earth is limited. Only in the year of 2013, China’s imports of crude oil as high as 282 million tons, the foreign dependency is close to 60%. Not only does this bring to our national’s economy a serious burden, but also endangering the safety of China’s energy strategy. So looking for a suffciency, environmentally friendly alternative energy source is the fundamental way to ensure sustainable development of our economy, ease the energy crisis and solve the environmental pollution problems. Bio-oil as a clean and renewable energy, to alleviate the energy crisis is a good alternative fuel for power machines.This paper studied the spray characteristics of Biomass Pyrolysis Emulsified Oil, regarded content of 5% of Biomass Pyrolysis Emulsified Oil which after distillation refining as research object, with the pure diesel and pure biomass pyrolysis emulsified oil as comparative study object. According to spray droplet size distribution function which based on the maximum entropy principle and the law of mass conservation, this paper wrote programs of the spray droplet size number distribution and Sauter mean diameter of numerical calculation by FORTRAN program language. In the condition of the fuel injection pressure of 16 MPa, 20 MPa, 24 MPa, nozzle diameter is 0.26 mm, 0.315 mm and 0.366 mm respectively, this paper had theoretical calculations to biomass pyrolysis emulsified oil under the condition of mass ratio of 0%, 5%, 100%.Then obtained droplet size number distribution curve and sauter mean diameter of the graph.The initial value of lagrangian factor coefficient variation β was calculated in computer programs. The coefficient variation β had small variations for both BPO 0 and BPO 5, which were changed between from 1.18 to 1.23. With the increase of nozzle diameter, β increases, with the increase of injection pressure, β decreases, BPO 100 had a larger range of variation compared with others. With the decrease of nozzle diameter and the increase of injection pressure, the droplet spray size distribution focused in a small particle size, the PDFN peak increases and the SMD(Sauter Mean Diameter) decreases. These led to a better atomization effect. The three emulsion fuels had the same overall trend of size distribution curves. With the changes in injection pressure、nozzle diameter and different mass scale of biomass pyrolysis emulsified oil, the theoretical calculated D32 of emulsified oil was fitting well with experimental results. With the increase of injection pressure, the decrease of the biomass proportion of oil became small, the atomizing quality got better. The theoretical calculation results of spray droplet size number distribution for Biomass pyrolysis emulsified oil fitting well with the experimental results. The curves have the same variation trend.Overall, the theoretical and experimental results a higher degree of compliance. The theoretical prediction of biomass pyrolysis emulsified oil spray quality assessment is accurate. The theoretical model is scientific credibility.