| The research to the Combustion Monitoring and Simulation & Optimization Expert System (i.e. CMSOES) for tangential fired pulverized coal boilers has a very important significance to monitors operating situation of the boiler, to enhance the quality of supervising and controlling, to optimize the operation, to save energy and decrease wastage. In this dissertation, the CMSOES had been studied and developed by using technology of digital measuring, numerical simulation and fuzzy theory, which includes the on-line monitoring system of air and pulverized coal, the instruction system for optimizing-operation and dynamic simulation system of burning situation, by analysing the boiler's structure and problems in its running, and by demonstrating and comparing the technology and means according to the need of the practical produce process and to economy and utility.The main work in this dissertation is as follows:1. By fully demonstrating and comparing the measurement means in existence, choosing the Difference-pressure Method, which is more reliable and economical, to monitor and measure flux and velocity of the primary and second air from every burner of boiler, and the author has researched the measuring model. The model precision reaches that relative error is less than 2%.2. By fully demonstrating and comparing the technology means in existence, choosing the Energy Balance Method, which is utility and economical, to determined the flux of pulverized coal transported by the primary air in every burner of boiler, and the author has modified the traditional model of Energy Balance Method. The model precision reaches that relative error is less than 5%.3. By establishing the model of two-phase flow, heat transfer and combustion in the furnace with applying the k- e - f -g model for gas-phase and the random trajectory model for solid-phase, adopting the limited difference way and the SIMPLEC arithmetic, and taking the commerce software CFX4.3, coupling simulated the velocity field, the temperature field, the density field and the burning-releasing heat field, and the relation between all sorts of operation parameters and the temperature distribution in boiler has been fully researched.4. Put forward the two-stage numerical simulation method and obtained the technique taking the results of off-line numerical simulation transplant into on-line dynamic simulation, and realized the dynamic real time display of temperature profile in the boiler by establishing the mathematic model (i.e. the quantify relation) which describes the temperature distribution in the furnace effected by all sorts of operation parameters. The model precision reaches that relative error is less than 12%.5. According to the data from the on-line monitoring system of air and pulverized coal, by adopting the practice experience of the local process experts and the operators, and applying the deep or simple knowledge and the fuzzy theory, established the fault diagnosing expert system for online monitoring system of air and coal, put forward the calculate-ratiocination model about the best proportion of air and pulverized coal, and constructed the expert system to optimizing and directing the adjusting all of operation parameters and can realized evaluating in real time to the flux of air and pulverized coal from each corner.6. Applied the "King of Assembly Function Software (V.6.01) " made in China to develop a integration-software system which is utility and fit for on-line monitoring of air and coal, dynamic simulation of the burning situation in furnace and direction in real time of the optimizing-operation, perfected the supervising means to the running of this kind of boiler.There are main conclusions in the dissertation: By being modified, the on-line monitoring model of air and pulverized coal is enough precisely to satisfy the need of engineering application. The results by coupled simulating vary physics fields in boiler are better accord with the measuring resu...
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