【作者】 陈宝清；

【导师】 白玉川；

【作者基本信息】 天津大学 ， 水力学及河流动力学， 2009， 硕士

【摘要】 卧倒门是船坞坞门的一种型式,主要用于干船坞,近年来随着船坞建设的发展,得到了普遍应用。它的卧倒与浮起是通过调节空气操作舱的进出气流实现的,对船坞的起卧性能起着至关重要的作用。一般设计主要是根据规范和相关经验满足其卧倒门基本的起卧性能,然而对于其起卧性能的评价主要还是依赖于物理模型试验,这主要是由于它在水中的运动状态比较复杂,受到多种因素的影响,如潮汐舱的水气孔的面积、空气操作舱水气交换的相互作用、水流、风浪等等。本文主要考虑了空气操作舱内的水气交换对坞门性能的影响,对卧倒门呈卧倒状态时操作舱内的气液分布进行了数值计算与试验模拟。以福建泉州1#船坞卧倒门为原型,结合模型门的尺寸建立二维数学模型,对空气操作舱的水气交换进行数值模拟研究。采用VOF模型追踪自由液面以确定流体的运动,并采用Reynolds平均法和低Re数的k ~ε模型进行计算。给定了边界条件:进口边界给定质量流量进口;出口为压力出口;采用对称边界取空气操作舱的一半,以减小网格数量,增加计算的速度;壁面使用固壁边界,通过壁面函数对近壁区域进行处理;对自由面的处理采用几何重构的办法。对计算模型建立控制方程,并采用有限体积法离散,压力—速度的耦合采用SIMPLE算法进行计算。通过对操作舱二维的计算,得到气液相瞬态分布和水的体积分数。采用有机玻璃模型对操作舱进行了静态状况下水气交换的模拟试验,通过改变空气压缩机的压力和水位的变化,得到不同状况下操作舱内水气交换的情况。并将试验数据和计算结果进行了对比分析。更多还原

【Abstract】 The draping-down door which is one kind of all docks is mainly bulit in dry docks. In recent years, many draping-down doors have been bulit successfully with the dock construction. The door is made to fall down or get up by compressed air of operating cabin, which is important to the draping-down door. At present, it is designed according to the theory of statis balance and relate criterion. However, the analysis whether the door moves badly or stablely is merely depent on physical model, because many factors affect its movement, such as the size of hole in the tidal cabin, the gas-liquid exchange in operating cabin, wind and wave. While the gas-fluid exchange makes a significantly impact on the draping-down door, the paper mainly studys the gas-liquid distribution of operating cabin by numerical simulation and experiment.This paper is based on the 1# draping-down door in Quanzhou, Fujian province. Seting up the mathematical model in virtue of the model size of the operating cabin, the air intaking and water discharged is simulated. VOF model is to track the free surface to determine the volume fraction of water in accounting model, and using the Reynolds averaging method and k ~εmodel to calculate. The boundary condition is ensured. The import border boundary is mass flow condition, and the export boundary is pressure condition, the use of symmetric boundary is to calculate the half cabin in order to increase the speed and the precision, solid wall boundary wall is the wall function to treat with near wall region. The free surface is treated with the Geometric reconstruction. The control equations are discreted by the FVM method, and the model by the coupled of the pressure - speed calculated by the SIMPLE algorithm. We can get the transient gas-liquid distribution and the volume fraction of water.The operating cabin of model door is made by plexiglass to make experimentation. By changing the pressure of air compressor and water level, we can get the gas-liquid distribution and the displacement of the cabin. And the calculated results and experimental data were compared and analyzed.更多还原