论文标题:油田水系统模型结构参数反演方法研究
Inverse Study to the Structure Parameters of Water System Models in Oil Field
论文作者 任永良
论文导师 常玉连,论文学位 硕士,论文专业 化工过程机械
论文单位 大庆石油学院,点击次数 42,论文页数 78页File Size2769k
2003-03-05论文网 http://www.lw23.com/lunwen_743156532/ 反演;水系统;注水;供水;管网;数学模型;优化;可变容差法;约束变尺度法;最小二乘;状态估计
inversion,water system,water flooding,water supplying,pipe network,mathematical modal,optimization,the flexible tolereance method,constrained variable metric method,least-square method,state estimating
在油田水系统进行仿真计算、管网改造计算和参数优化计算过程中，涉及到系统管网的基础数据，这些基础数据是上述各项计算的基础。由于油田所能提供的水系统管网基础数据都是原始设计数据，在管线建设施工和管网维修改造中，管网结构参数与原始结构尺寸肯定有所出入，有的甚至差别很大，这些差别只要对照实际情况是可以校正过来的；但有些管线在几十年的运行过程中，由于腐蚀、杂质沉淀、结垢等原因导致管线壁厚增加、实际内径减小等，与水系统仿真数学模型采用的原始设计数据产生差异，从而导致仿真、改造和优化计算误差增大，影响实际应用。针对上述情况，本文对油田水系统管网模型结构参数反演方法研究，旨在通过对实际测试数据的分析，估计出管子参数的实际值，为下一步的仿真优化和管网改造提供较正确的基础数据。 本文针对油田水系统管网的仿真模型进行了深入研究，在分析了矩阵方程和总体方程的特点基础上，提出了管网系统的简化策略，通过计算分析证明迭代法可有效的解算水系统管网问题。 本文建立了管网系统的状态估计方程，运用最小二乘法和快速状态估计法对管网进行状态估计，提出了错误参数识别和纠正方法。 本文建立了水系统结构参数反演求解的数学模型，将反演问题转化为一个求解最优化问题。根据数学模型的特点，深入研究了可变容差法和约束变尺度法求解此类问题的可行性，并对两者结果进行了分析，确定了约束变尺度法作为求解本问题的方法。 编制了油田水系统(供水和注水)管网结构参数(管径)求解的软件，通过对大庆油田某供水管网和大庆采油六厂的注水管网进行计算，证明该软件能够适用于求解油田供水管网和简单注水管网的参数(管径)反演问题。
During the course of calculations of simulation,pipe network"s reconstruction and prameters optimization to the water systems in oil field,the pipe-net"s foundation datas are all involved. These foundation datas are the base of the above calculations.At the same time,the pipe"s datas we obtained from oil field usually are original design datas.In the construction,maintenance and reconstruction to the pipes.some datas are maybe different from original datas.Some difference are even very greatly.These differences may be corrected as long as we contrasted the real instances. But the more important is that some pipes come into being thicken wall,real internal diameter reducing and so on due to corruption and impurity precipitated in the operating course of tens years.These problems can lead to increase the resistance losses ,reduce the volume of flow etc and enlarge the calculation error.As a result, simulation,pipenet"s reconstruction and optimization calculation will lose their original meaning. At the same time, we can"t solve these problems by way of direct measurement.In accordance with the mentioned above circumstances,the dissertation develops the inverse study to the structure parameters of water system models in oil field.The dissertation sets up mathematical models of pipe networks to describe working status of oil field water systems. It also sets up unit equation based on pressure loss and general equation group of pipe network system based on flow balance principle of node. After analyzing characteristic of matrix and general equation group, reduction tactics of pipe network is developed. It is found out that iteration method is fit for computing the general equation of flow pipe system through calculating and analysing.The dissertation sets up the state estimating function of pipenet system,use the east-square method and quick_state_estimating method to estimate the pipenet"s state.To the wrong parameter,put forward recognition and correction methods.The dissertation sets up mathematical models of water system"s structure parameters" inversion.It sums up the inverse problem into a optimizing problem.According to the characteristics of the optimizing model,it puts forward using the Flexible_Tolereance method and Constrained_Variable_Metric method to solve the problem, analyses the both method"s results and defines Constrained_Variable_Metric method as the finally method.The dissertion programs the software of solution to pipenet"s construct parameters of water system in oil field . The software is used to water system in Putaohua oil field and the result shows that the study can decrease the calculation error and increase the calculation precision.
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