Its research purpose and significance
Energy is the power of social operation, oil as the most important fossil energy known as the “blood of industry”. In 2016, China’s oil import continued to grow, with the apparent oil consumption exceeding 556 million tons and the foreign dependence reaching 64.4%, an increase of 3.8% compared with 2015. As oil consumption continues to rise, environmental problems are becoming increasingly serious. Therefore, seeking renewable and environmentally friendly alternative fuels is of great significance to China’s energy security and environmental governance.
Biodiesel has been paid more and more attention as an alternative to fossil fuels due to its reproducibility, environmental protection, and performance. Traditional biodiesel production mainly uses vegetable oils such as rapeseed oil, soybean oil, palm oil and sunflower seed oil as raw materials, which requires a large number of land resources and has the problem of insufficient supply of raw materials. Algae are mostly distributed in coastal areas and lakes, with the advantages of fast growth rate, high photosynthetic efficiency, strong environmental adaptability, high oil content, simple processing technology, etc., known as the third generation of biodiesel, with great development potential. Chlorella is a kind of common algae, which is widely distributed in the long coastline of our country.
Acid-catalyzed one-step transesterification is an efficient and low-cost method for the preparation of biodiesel. At present, in domestic and foreign literature, using chlorella as raw material to prepare biodiesel, the variation of oil yield with a mass ratio of methanol algae, the concentration of sulfuric acid, reaction temperature, reaction time and stirring speed is rarely reported. In order to better guide the production of clock biodiesel, it is necessary to study the influence of various factors on the oil yield during the preparation of biodiesel.
The composition and physicochemical properties of Chlorella biodiesel determine its combustion performance in the engine. In order to analyze the performance of Chlorella biodiesel in the engine, it is necessary to measure the composition of Chlorella biodiesel and measure the physicochemical properties of Chlorella biodiesel.
As the combustion process in the engine is characterized by complex turbulence and chemical interaction, it has a strong transient. In order to grasp the fine flow field structure of the combustion process of an internal combustion engine, it is necessary to simulate the fuel combustion process accurately. With the development of Computational Fluid mechanics and combustion reaction Dynamics, it is one of the effective ways to deeply study the process of fuel combustion by coupling the combustion reaction Dynamics model of fuel with Computational Fluid Dynamics. The fuel combustion reaction kinetics model is the foundation of all these, so it is necessary to construct the Chlorella biodiesel combustion reaction, kinetics model.
The scale of the reaction dynamics model constructed by the superposition method is often too large, which will lead to the problem of numerical rigidity and the problem of too large calculation. In order to solve practical problems and reduce the requirement of calculation conditions, the detailed combustion reaction dynamic model needs to be simplified.