发散布孔条件下冻结壁温度场特性研究

发布时间：2018-04-14 18:52

本文选题：发散布孔 + 温度场　；参考：《中国矿业大学》2014年硕士论文

【摘要】：广佛线普君北路站～朝安站区间隧道管片处理冻结封水工程于隧道底部布置了发散的冻结管来进行堵水。为了获得冻结管发散布置条件下的冻结温度场分布及其发展规律，本文采用数值模拟和模型试验相结合的方法进行研究分析。建立Ansys数值模拟模型，进行单因素、正交分析以及多因素回归分析研究不同因素对发散布孔条件下冻结温度场的影响规律，并获得回归公式。通过单因素分析，，得到冻结壁厚度随着初始地温和相邻冻结管夹角的增大而减小、随着相邻冻结管排间距的增大而增大以及随着冻结管外壁温度的降低而增大等规律，而土体冻结温度对温度场影响不明显；冻结壁平均温度则呈现与冻结壁厚度相反的变化规律，其中，排间距对冻结壁平均温度的影响表现为先降低后升高；文章通过安排正交试验，得到了发散布孔条件下冻结温度场的显著性影响因素。其中，冻结壁厚度的显著性影响因素为冻结管外壁温度以及相邻冻结管的夹角。冻结壁平均温度的显著性影响因素为冻结管外壁温度、相邻冻结管夹角以及相邻冻结管排间距；而后，安排正交表利用数值模拟进行了多因素回归试验，通过计算结果分别得出冻结壁厚度、平均温度以及冻结壁轴面上环向发展宽度等目标量的多因素回归公式。通过物理模拟实验，研究了相邻冻结管夹角为10o和14o两个模型的冻结温度场，分析各特征面测点温度的变化情况以及特征面上的温度分布规律，并对比不同冻结管夹角的模型温度场分布的异同。通过模型试验得出，冻结初期，界面冻结温度场的发展要小于主面，在冻结后期，二者达到相近水平；增大冻结管间的夹角，将使冻结壁厚度降低，平均温度升高，冻结壁的环向冻结范围增大。文章通过对冻结壁厚度、平均温度以及冻结壁环向发展宽度随时间的变化曲线进行拟合，得出拟合公式，并进行求导，得出发散布孔条件下冻结温度场的发展速度公式。将数值模拟的计算结果与模型实验的结果进行比较，得出二者所得的温度场分布规律一致，但实验测值要小于数值模拟的数值，且在冻结管区域，数值模拟更能细致地反映出温度场的分布规律。综上所述，发散布孔条件下，各因素对其温度场具有不同程度的影响，其中冻结管外壁温度、相邻冻结管夹角以及冻结管排间距影响较为显著。在实验条件下，应严格控制实验过程，避免实验误差，并结合数值模拟分析冻结管附近区域的冻结温度场分布规律。本文通过多因素回归分析以及实验数据拟合得到的冻结壁厚度、平均温度及其发展速度公式，对相关工程有一定的参考指导作用。
[Abstract]:In order to obtain the frozen temperature field distribution and its development law under the condition of divergent placement of frozen pipe , the numerical simulation and model test are used to study the freezing temperature field distribution and its development law .

An Ansys numerical simulation model is established , and the influence law of different factors on freezing temperature field under the condition of distribution holes is studied by single factor , orthogonal analysis and multi - factor regression analysis .
The average temperature of the frozen wall is the opposite of the thickness of the frozen wall , where the influence of the row spacing on the average temperature of the frozen wall is decreased firstly and then raised ;
In this paper , the influence factors of freezing temperature field were obtained by arranging orthogonal test . Among them , the influence factors of freezing wall thickness were freezing tube outer wall temperature and the included angle of adjacent freezing tube . The significant influence factors of freezing wall ' s average temperature were freezing tube outer wall temperature , adjacent freezing tube included angle and adjacent freezing tube row spacing ;
Then , the orthogonal table is arranged to use the numerical simulation to carry out the multi - factor regression test , and the multi - factor regression formula of the target quantity such as the thickness of the frozen wall , the average temperature and the circumferential development width of the frozen wall axis is obtained through the calculation results .

Through the physical simulation experiment , the freezing temperature field of the two models with the included angle of 10o and 14o of the adjacent freezing tube is studied , the temperature distribution law of each characteristic surface temperature measuring point is analyzed , and the variation of the temperature distribution of the model of the included angle of the freezing tube is compared .
By increasing the angle between freezing tubes , the thickness of frozen wall is decreased , the average temperature is raised , and the freezing range of frozen wall is increased . By fitting the frozen wall thickness , the average temperature and the curve of frozen wall to the development width with time , the fitting formula is obtained .

The results of the numerical simulation are compared with the results of the model experiment , and the distribution law of the temperature field obtained by the numerical simulation is consistent , but the experimental values are smaller than those of the numerical simulation , and the numerical simulation can accurately reflect the distribution law of the temperature field in the freezing tube area .

In conclusion , the influence of various factors on the temperature field of the frozen pipe under the condition of distributing holes is significant . Under the experimental conditions , the experimental process should be strictly controlled to avoid the experimental error , and the distribution law of freezing temperature field in the area near the freezing tube should be analyzed by numerical simulation .

【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U451

【参考文献】