Research On The Oil Pipeline Crude Oil Temperature Drop Law In The Oil Depot

Aimed at the solidifying characteristic, the oil pipeline crude oil temperature drop law in the oil depot need be researched, thus it can avoid wasting the manpower and the material resources because of depending on the experience and increasing the initial lead produced by water pours.Considering the special environment and conditions of the pipeline in the oil depot, the oil pipeline crude oil temperature circuit monitor system is studied. It can complete the circuit monitor of the long-distance multiple points'temperature and the historical data inquiry, and it can automate the early-warning and warning according to the upper and lower limit set the temperature. The system's structure and the working principle are clarified detailedly in this thesis. Meantime the functions of the system's superordination and inferior are described. This system is suitable for the situations such as the bad environment, the far distance betw- een the field and chamber, the routing dispersion, and many interference sources.The system is installed at the north oil depot's eight pipelines of the daqing storage and transportation marketing branch company. By using the system, we get a lot of temperature data which is recorded after steadying the tanks. The data is arranged, analyzed and studied to obtain the relation of the temperature drop rate and the mean temperature difference for every pipeline. From the angle of experience, the oil pipeline crude oil temperature drop law are summarized.The experimental results indicate this law. Not only the relations between the tempera- ture drop rate and the mean temperature difference of the different oil pipelines are different, but also the relations of the different axial positions on the same pipeline are different. With the mean temperature difference increasing, the temperature drop rate of the oil pipelines located in right side of the center line increases, but the temperature drop rate of the left side pipelines appears a deceasing situation. There is no linear relation between the temperature drop rate and mean temperature difference. Eespecially, the temperature drop rate change is a complicated problem because there are many influence factors. The complexity of the influe- nce factors and the non-controllability of some factors result in the temperature drop rate change law's complexity and diversity, so the pipeline temperature drop in the oil depot this transient problem need to be put up the more all- around and further theory study.According to energy conservation, the oil depot pipeline thermal model is established by analyzing the initial conditions, the boundary conditions and the involved parameters. On the base of the finite difference method, the oil depot pipeline thermal calculation software is compiled to solve the model, which can calculate the current crude oil temperature, the curr- ent temperature difference and the current temperature drop rate.The theoretical temperature drop law and the experimental temperature drop law are compared and they are consentaneous a certain extent on some condition, thus the validity of the model is verified. But they also have some more obvious difference. The relevant factors that cause the difference are analyzed detailedly in this thesis.