폐식용유를 이용한 바이오디젤유(BDF)의 연소특성

Abstract

Recently many researchers have been studying the development of alternative energy due to serious pollution and drying up of fossil energy. BDF(Bio Diesel Fuel) using from wasted vegetable oil is one of the alternative energy. BDF must be esterified because of its high viscosity compared to diesel fuel in using as the fuel of the diesel engines. The price of the BDF grows higher due to the complex manufacturing process. If the manufacturing process of the blend oil is simpler than that of TVO, the blend oil will be cheaper and can be used easily. This research analyzed combustion characteristics of the diesel engine using the diesel fuel, TVO and Blending Oil. Especially PM mass with the light absorption method was measured quantitatively. The PXI and LabVIEW was applied for signal acquisition on the test engine. PXI and LabVIEW are a novel measurement system which is possible to acquire and analyze the signal on-line. There were some papers for diesel engine performance tests using BDF, but the papers for droplet distributions and SMD of diesel spray and two-color method for BDF were rarely found. Droplet distributions and SMD of BDF were measured in this study. Droplet were sampled with a conventional immersion sampling method and were taken the image of droplets by optical microscope with CCD camera. The image of droplets distributions were measured using image processing program such as Sigma Scan. The flame temperature of diesel engines is high and subject to change rapidly and an optical method for measurement is most effective. The two-color method regarding the visible wavelength radiation for the soot particles in flame was closely studied in order to establish the measuring technique of the flame temperature and the soot concentration in a diesel engine. The results were as follows: 1) As the ambient pressure on every sample oil increased, the distribution of important droplets increased. BO and TVO were similar to light-oil on SMD when the ambient pressure becomes 1bar, but the ambient pressure increased over a certain level(3bar), the change of SMD was low relatively. 2) The Two-Color Method using chip photodiode instead of former method using expensive PMT could also get reliable data. 3) DF, BO, TVO in order showed the peak combustion temperature at 1500rpm and 2000rpm and also KL value showed the same tendency. 4) The combustion pressure and heat release rate could be measured by on-line using PXI and LabVIEW. 5) The combustion pressure movements of BO and TVO using used substitute oil are similar to that of light-oil, and it means that using of BO and TVO is possible to use as an alternative fuel. 6) The three kinds of fuel mentioned above was almost same in NOx emission tendency, but TVO in low speed was in NOx emission. In case of the emission of CO, DF had the highest and TVO had the lowest. As far as PM concerns light oil was a little higher than BO and TVO in same rpm and same load.