【作者】 冼海珍；

【导师】 周少祥；

【作者基本信息】 华北电力（北京）大学 ， 热能工程， 2002， 硕士

【摘要】 随着人口的增长、社会发展和人民生活水平的不断提高，沿海淡水资源短缺问题将日益严重，海水淡化技术将成为21世纪解决沿海淡水供应问题的必然选择。MSF多级闪蒸技术是国际海水淡化市场的主力军，其装置的国产化研制是一项非常重要的科研课题。对于管式换热器，本文在全面分析总结分布参数模型的解析解及其简化方法的基础上，充分研究了分段线性化处理方法，并进行详细的仿真计算，得出了一些有益的结论。本文推导出分段后总传递函数的形式，并证明当分段数趋于无穷大时，其结果与分布参数模型的解析解完全相同，从而也证明了可以通过提高分段数改善仿真计算结果的精度。本文根据热工理论，以每一级闪蒸器为单元，建立了MSF系统动态过程的数学模型和MATLAB仿真模型，比其他文献提供的模型更完善，考虑的因素更全面。将各级之间的联系以耦合扰动向量的形式给出，不仅有助于理解扰动的耦合作用，还避免了建立大型的系统整体状态矩阵，使仿真计算变得更容易。在此基础上，详细研究了MSF系统动态过程数学模型的线性化处理方法，并进行了仿真计算。为MSF装置的运行调整与控制策略的制定提供了决策依据，为MSF系统的国产化研制提供技术支持。更多还原

【Abstract】 With increasing of population and development of society, the shortage of fresh water resource of the coastland in China will become more severe. It is necessary to select desalination of seawater to solve the supply of fresh water in 21 century. The technique of multi-stage flash (MSF) distillation is dominant and widely used in the market of desalination at present in the world. Therefore, it is necessary to develop more advanced MSF desalination equipment made in China. Based on research experience published in literatures, dynamic behavior of MSF system was focused on in this paper.The brine heater, a tube heater with single import and export, is one of the main devices for the MSF system. Although it is not difficult to model and simulate its dynamic process for such a heater, some mistakes in literature are found. On the basis of the consideration of distributing parameter model and its simplification a linear ramp method with subsection is presented and a simulation is accomplished. For the various disturbance factors, the manners of connections between the subsections are not the same and can be not simply treated as a series structure; otherwise a mistake will take place. For the step temperature disturbance of seawater, the manner of connection between the subsections is in series. But for step flow disturbance of seawater or heat disturbance, due to simultaneity of effects of these step disturbances on the whole system space, the manner of connection is either in series or in parallels.The dissertation presents the total transfer functions with three step disturbances of subsection linearization, and proves that the limits of the total transfer functions are the same as the analytical solution, if the number of subsection goes to infinity. Therefore, the precision of simulation can be improved by increasing the number of subsection.According to thermodynamic theory, the dissertation establishes the mathematical models of dynamic process of the MSF system and the Matlab simulation models on the basis of each flash evaporator unit. The models are better than the ones presented by other references. The connection between one stage and another stage is expressed as a vector of coupling disturbance, which makes it easy to understand the coupling effects of disturbance and avoids of establishing large state matrix of the whole system, and makes it easy to simulate. The linearization methods of the mathematics models for dynamic process of the MSF system are studied and case studies are given. The aforementioned researches and analyses can provide the help on making operation regulation and control strategy of the MSF system.更多还原