Study On The On-line Inspection Method Of Biodiesel Ratio Of Biodiesel Blend In Vehicle

Along with exhausted of traditional energy year by year, people need develop renewable energy; the clean energy is favorable to environment protection and auto industry. Biodiesel is an renewable diesel fuel consisting of the alkyl monoesters of fatty acids from vegetable oils and animal fats. As an alternative diesel fuel, it is comprehensive accepted by world researchers. Biodiesel has good performances of energy and it is friendly to environment. There are much advantage to develop biodiesel industry in our country. It is important to energy security, environment protection, and it can promote income of farmers, develop agriculture and production industry.Biodiesel is a renewable green energy, it is not exhausted. As good physical and chemical properties, biodiesel can be used in diesel engines as a pure fuel or in blend with petroleum-based diesel fuel. The performance of biodiesel is researched by our group and other teams. The results show that engine performances of biodiesel and the blend are similar to those of diesel fuel,but Smoke decreases remarkably with slight increase in NOx; The peak pressure is higher,the injection delay and duration exhibit a slightly longer,which made a higher fuel injection per cylinder cycle,at the same fuel delivery advance angle,engine speed and load,when the biodiesel ratio increases. Economic performance is slightly lower; As calorific value per mass of biodiesel is lower than diesel's, dynamic performance is slightly lower, too.Therefore, to maintain optimum performance and meet emission regulations, it may be necessary to measure the composition of blended fuels and adjust the fuel injection timing and other injection parameters during operation.According to above, the main work of this thesis is as follows:1. Theory Analysis and ResearchAccording to the analysis of physical and chemical properties of biodiesel, we decide use permittivity method and infrared spectroscopy method to inspect biodiesel ratio of biodiesel blend. Then we introduce the detection theory of permittivity method and Infrared Spectroscopy method, it is the theoretical basis of the on-line inspection.2. Test Research We use the biodiesel which is made by soybean oil from Kai Lan Shen industrial foreign trade limited company in Beijing. We use -35# petroleum-based diesel fuel which is used in winter in northeast of China, and we use 0# petroleum-based diesel fuel which is used in spring and autumn in northeast of China. Then we blend the biodiesel with the -35# diesel fuel and 0# diesel fuel respectively, and define the biodiesel blend with -35# diesel fuel as group 1, the other is group 2.1) We inspect the relative permittivity of different biodiesel ratio of biodiesel blend of two groups in laboratory.2) We inspect the near-infrared spectra of different biodiesel ratio of biodiesel blend of two groups and mid-infrared spectra of different biodiesel ratio of biodiesel blend of group1 in laboratory.3. Data Processing1) First draw two scatter diagrams from test date of the relative permittivity of two groups. According to date processing, we get the linear relationship between the permittivity and biodiesel ratio of biodiesel blend. When different kinds of petroleum-based diesel fuel blend with biodiesel , it is shows that the relative permittivity of the biodiesel blends are almost the same by the test data and the result of data processing.2) First pretreatment the near-infrared spectra of different biodiesel ratio of biodiesel blend of two groups by chemometrics, then we establish two models by PLS method.The models can predict the biodiesel ratio of biodiesel blend respectively. But it can't generally predict the biodiesel ratio of biodiesel blend, it is not suit for the on-line inspection system.3) First compare and analyze the mid-infrared spectra of different biodiesel ratio of biodiesel blend of group1.It is obviously different in wave band 1750cm-1 in the mid-infrared spectra, the biodiesel has a obvious absorption peak. According to Lambert - the Bill law and the test result , we get the linear relationship between the absorption peak in wave band 1750cm-1 and biodiesel ratio of biodiesel blend. it is suit for the on-line inspection system.4. Preliminary Design of on-line InspectionAccording to the results of the theory and test processing, we design two on-line inspection system of biodiesel ratio of biodiesel blend in vehicle. Designs two primary structures of monitor system, then compare and analyse between the two systems.