The Research On Two-phase Flow Modeling Of Alumina Dense Phase Conveying And The Measurement Of Parameters

In the electrolytic aluminum production, the transportation of alumina is a very important link. Particularly in large pre-baked electrolytic cell production, as difficult to use artificial feeding, alumina delivered smoothly or not will have a direct impact on the normal cell production. Dense-phase conveying is an advanced materials technology has been used in many fields of industry. At present, only some of the domestic fields in color has adopted dilute-phase and dense-phase, hyper dense-phase conveying technology, some enterprises in the power generation have adopted dense-phase conveying technology, the other enterprises in the field of cement have adopted the dilute-phase conveying technology, most other fields of industry have adopted the open-transportation methods. With its advanced nature, dense-phase conveying has been used widely in industrial applications. However, because the transmission process is a compressible pneumatic conveying process, the physical mechanism is more complex. To really make this technology applied to industrial production, we must be nimble two-phase flow theory for its detailed analysis, modeling and calculation.At the above-mentioned purpose, this thesis is modeling the process of alumina dense-phase conveying, and measuring the concentration of alumina powder, which is not easy to measure.This paper first gives difference between the concepts of dilute-phase, dense-phase and hyper dense-phase, and analysis the principle of dense-phase conveying. In a detailed briefing on the study of two-phase flow, the three main models: continuum model, discrete particle model, pseudo article model. Selection continuum model, we have established a two-phase flow model of alumina dense-phase conveying. And the use of data collected in the field, using computational fluid dynamics analysis software for the simulation of the model created. The simulation results demonstrate that the model used to the conditions, verify the validity of the model.In the second part of the thesis, I put a measurement program of the concentration of alumina powder in the course of transmission, which uses the soft measuring techniques and data fusion techniques. Two capacitance sensors are chosen as physics sensor. Meanwhile, the linear regression method to build a softmodel of the concentration of alumina powder and wind pressure of exports measurement, the soft model is looked as a soft sensor. Finally, the method of data fusion is used for the integration processing of the three sensors data, after certification proves that the result is better than as a any single sensor's result,shows that this program has a high reliability and accuracy of measurement, it can be applied to measuring the concentration of alumina powder.