液压升降坝泄流特性试验研究
发布时间：2018-11-01 15:01
【摘要】：液压升降坝是一种新型的可自动升降的拦河活动坝,具有挡水和泄水双重功能。目前在国内蓄水及城市美化工程中得到了较为广泛的应用。对液压升降坝在不同开启方式下泄流能力的计算是解决河道行洪安全的关键问题。液压升降坝过流方式与传统的拦河活动坝有所不同,泄流能力的大小无系统的计算方法。本文采用物理模型试验的方法研究液压升降坝的泄流特性,选择了常见的3m、4m和5m坝高的液压升降坝作为原型,每种坝高设计三扇坝,模型比尺为1:30,在有机玻璃水槽上进行了泄流试验。保持两端液压升降坝为正常运行挡水状态,将中孔液压升降坝调整到各种塌坝角度(0°,14°,28°,42°,56°,70°),对液压升降坝的流态类型、泄流量变化规律、流量系数的影响因素、流量计算公式以及流量系数计算方法等进行了分析,主要结论如下:(1)观察试验发现,液压升降坝在塌落运行中主要存在三种流态。一种是三扇液压升降坝均保持正常挡水运行状态,上游来流时,上游水位壅高,水流均匀地从液压升降坝坝顶流过,此时类似矩形薄壁堰堰流。另一种是液压升降坝两端坝保持正常挡水运行状态,中孔液压升降坝调整到不同支撑角度(14°、28°、42°、56°),上游来流时,水流一部分从中孔液压升降坝与两端坝之间的三角夹缝流过,一部分从中孔液压升降坝坝顶流过,此时流态相当于矩形薄壁堰与三角形薄壁堰的结合。最后一种是保持两端坝为正常挡水运行状态,中孔液压升降坝塌平紧贴水槽底面,上游来流直接从中间留出,类似于宽顶堰堰流。(2)当三扇液压升降坝均处于正常挡水运行时,液压升降坝流量系数m与H0/P1存在较好的线性关系,且随H0/P1增大而增大;流量系数m均处于0.4—0.45之间。类似矩形薄壁堰,流量计算可以用公式进行。流量系数计算可以按照经验公式。式中H0是指液压升降坝坝顶水头,P1是指液压升降坝垂直挡水高度。(3)当液压升降坝两端处于正常挡水运行状态,中孔坝塌落到各种支撑角度下时,流态相当于三角形薄壁堰与矩形薄壁堰的组合。流量计算公式可以用:,式中H为中孔液压坝垂直挡水高度,H0为坝顶水头。C为三角形薄壁堰流量系数,经过试验数据拟合出来公式为:,m按照量纲分析拟合出的经验公式进行计算。,其中P1为液压升降坝垂直挡水高度。同一坝高下,支撑角度越大,流量系数越小。同一支撑角度下,坝高越高,流量系数m越小,变化幅度较小。(4)液压升降坝两端处于正常挡水运行状态,中孔液压升降坝塌平紧贴有机玻璃水槽底面时,其过流流态类似于宽顶堰堰流。其流量计算可以参考宽顶堰流量计算公式其中流量系数m可以参考经验公式 进行计算。
[Abstract]:Hydraulic lifting dam is a new type of automatic moving dam with double functions of retaining and discharging water. At present, it has been widely used in water storage and urban beautification projects in China. The calculation of the discharge capacity of hydraulic lifting dams under different opening modes is the key problem to solve the safety of river flood discharge. The hydraulic lift dam is different from the traditional river moving dam in the way of flow passing, and there is no systematic calculation method for the discharge capacity of hydraulic lift dam. In this paper, the physical model test method is used to study the discharge characteristics of hydraulic lifting dams. The hydraulic lifting dams with the height of 3 m and 5 m are selected as prototypes. Three dams are designed for each height, and the model scale is 1: 30. The discharge test was carried out on the plexiglass tank. In order to keep the hydraulic lifting dam at both ends in normal running condition, the hydraulic lifting dam with medium hole is adjusted to various collapse angles (0 掳, 14 掳, 28 掳, 42 掳, 56 掳, 70 掳). The main conclusions are as follows: (1) observation and test show that there are three main flow patterns in collapse operation of hydraulic lifting dams. One is that the three hydraulic lifting dams are in the normal state of retaining water. When the upstream flow comes up, the upstream water level rises and the water flows uniformly through the top of the hydraulic lift dam, which is similar to the rectangular thin-walled Weir flow. The other is that the two ends of the hydraulic lifting dam keep the normal running state of retaining water, and the hydraulic lifting dam of the middle hole adjusts to different supporting angles (14 掳, 28 掳, 42 掳, 56 掳). A part of the flow of water flows through the triangular joint between the middle hole hydraulic lifting dam and the two end dams, and one part of the middle hole hydraulic lift dam flows through the top of the dam. At this time, the flow pattern is equivalent to the combination of the rectangular thin-walled Weir and the triangular thin-walled Weir. The last one is to keep the two ends of the dam in the normal state of retaining water, and the hydraulic lift dam with a middle hole collapses and flattens close to the bottom of the flume, and the upstream flow is left directly from the middle. It is similar to the Weir flow of wide top Weir. (2) when the three hydraulic lifting dams are in normal water retaining operation, the flow coefficient m of hydraulic lift dam has a good linear relationship with H0/P1, and increases with the increase of H0/P1; The flow coefficient m is between 0.4-0.45. Similar to rectangular thin-walled Weir, flow calculation can be done by formula. The flow coefficient can be calculated according to empirical formula. H0 refers to the head of the top of the hydraulic lift dam, and P1 to the vertical water retaining height of the hydraulic lift dam. (3) when the two ends of the hydraulic lift dam are in the normal state of retaining water, the mesopole dam collapses under various supporting angles, The flow state is equivalent to the combination of triangular thin-walled Weir and rectangular Thin-walled Weir. The formula of flow calculation can be used: h is the vertical water retaining height of hydraulic dam with mesopole, H _ 0 is the head of dam top, C is the flow coefficient of triangular thin-walled Weir, and the formula fitted by test data is as follows: M is calculated according to the empirical formula of dimensionality analysis, where P1 is the vertical water retaining height of hydraulic lifting dam. Under the same dam height, the larger the supporting angle, the smaller the discharge coefficient. At the same supporting angle, the higher the dam height, the smaller the discharge coefficient m, and the smaller the range of variation. (4) when the two ends of the hydraulic lift dam are in the normal water retaining operation state, the hydraulic lift dam with medium hole collapses and flattens close to the bottom of the plexiglass flume. The overflow pattern is similar to that of Weir flow with wide ceilings. The calculation of the flow rate can refer to the formula of the flow rate of the broad-topped Weir, where the flow coefficient m can be calculated with reference to the empirical formula.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV64;TV135.2
本文编号：2304273
[Abstract]:Hydraulic lifting dam is a new type of automatic moving dam with double functions of retaining and discharging water. At present, it has been widely used in water storage and urban beautification projects in China. The calculation of the discharge capacity of hydraulic lifting dams under different opening modes is the key problem to solve the safety of river flood discharge. The hydraulic lift dam is different from the traditional river moving dam in the way of flow passing, and there is no systematic calculation method for the discharge capacity of hydraulic lift dam. In this paper, the physical model test method is used to study the discharge characteristics of hydraulic lifting dams. The hydraulic lifting dams with the height of 3 m and 5 m are selected as prototypes. Three dams are designed for each height, and the model scale is 1: 30. The discharge test was carried out on the plexiglass tank. In order to keep the hydraulic lifting dam at both ends in normal running condition, the hydraulic lifting dam with medium hole is adjusted to various collapse angles (0 掳, 14 掳, 28 掳, 42 掳, 56 掳, 70 掳). The main conclusions are as follows: (1) observation and test show that there are three main flow patterns in collapse operation of hydraulic lifting dams. One is that the three hydraulic lifting dams are in the normal state of retaining water. When the upstream flow comes up, the upstream water level rises and the water flows uniformly through the top of the hydraulic lift dam, which is similar to the rectangular thin-walled Weir flow. The other is that the two ends of the hydraulic lifting dam keep the normal running state of retaining water, and the hydraulic lifting dam of the middle hole adjusts to different supporting angles (14 掳, 28 掳, 42 掳, 56 掳). A part of the flow of water flows through the triangular joint between the middle hole hydraulic lifting dam and the two end dams, and one part of the middle hole hydraulic lift dam flows through the top of the dam. At this time, the flow pattern is equivalent to the combination of the rectangular thin-walled Weir and the triangular thin-walled Weir. The last one is to keep the two ends of the dam in the normal state of retaining water, and the hydraulic lift dam with a middle hole collapses and flattens close to the bottom of the flume, and the upstream flow is left directly from the middle. It is similar to the Weir flow of wide top Weir. (2) when the three hydraulic lifting dams are in normal water retaining operation, the flow coefficient m of hydraulic lift dam has a good linear relationship with H0/P1, and increases with the increase of H0/P1; The flow coefficient m is between 0.4-0.45. Similar to rectangular thin-walled Weir, flow calculation can be done by formula. The flow coefficient can be calculated according to empirical formula. H0 refers to the head of the top of the hydraulic lift dam, and P1 to the vertical water retaining height of the hydraulic lift dam. (3) when the two ends of the hydraulic lift dam are in the normal state of retaining water, the mesopole dam collapses under various supporting angles, The flow state is equivalent to the combination of triangular thin-walled Weir and rectangular Thin-walled Weir. The formula of flow calculation can be used: h is the vertical water retaining height of hydraulic dam with mesopole, H _ 0 is the head of dam top, C is the flow coefficient of triangular thin-walled Weir, and the formula fitted by test data is as follows: M is calculated according to the empirical formula of dimensionality analysis, where P1 is the vertical water retaining height of hydraulic lifting dam. Under the same dam height, the larger the supporting angle, the smaller the discharge coefficient. At the same supporting angle, the higher the dam height, the smaller the discharge coefficient m, and the smaller the range of variation. (4) when the two ends of the hydraulic lift dam are in the normal water retaining operation state, the hydraulic lift dam with medium hole collapses and flattens close to the bottom of the plexiglass flume. The overflow pattern is similar to that of Weir flow with wide ceilings. The calculation of the flow rate can refer to the formula of the flow rate of the broad-topped Weir, where the flow coefficient m can be calculated with reference to the empirical formula.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TV64;TV135.2
【相似文献】
相关期刊论文 前10条
1 彭儒武,李保栋,王青,吴新岭;矩形薄壁堰贴壁堰流试验研究[J];山东农业大学学报(自然科学版);2002年02期
2 朱海燕;陈建芬;王文全;;厂房尾水薄壁堰三维非线性有限元分析[J];云南水力发电;2008年05期
3 张丛风,陶冶;寒带溢流薄壁堰的结构设计和应用[J];黑河科技;1997年04期
4 周栋城;杨丽珍;林艳;;梯形薄壁堰在山西省万家寨引黄一期工程中的应用[J];科技情报开发与经济;2007年29期
5 S．吴,韩瑞光;矩形薄壁堰的淹没水流[J];水利水电快报;1997年05期
6 邸国平;引黄南干线7~#洞出口明渠梯形薄壁堰流量系数的选定[J];山西水利科技;2004年04期
7 李冬艳;李璐璐;;寒带溢流薄壁堰的结构设计和应用[J];黑龙江科技信息;2014年10期
8 胡荣辉,齐清兰,王英华;田间配套一字闸流量系数初探[J];河北水利专科学校学报;1991年01期
9 彭儒武;张昕;彭英慧;;矩形薄壁堰贴壁流水力学特性的试验研究[J];华北水利水电学院学报;2012年03期
10 徐玲君;陈刚;李国栋;薛阳;;薄壁堰泄流能力的数值模型计算及模拟自由水面的评价[J];西北农林科技大学学报(自然科学版);2010年01期
相关会议论文 前1条
1 吴德星;张淑芬;于维强;李永福;;连拱薄壁堰在小型拦河截流工程中的应用技术研究[A];山东水利学会第八届优秀学术论文汇编[C];2003年
相关硕士学位论文 前1条
1 谢良平;液压升降坝泄流特性试验研究[D];太原理工大学;2017年
，本文编号：2304273
本文链接：https://www.wllwen.com/kejilunwen/shuiwenshuili/2304273.html
