[关键词]
[摘要]
凌庄子水厂蓄水池进水口处有一保水堰,为非标准薄壁堰,不能使用已有堰流公式对其过流量进行准确计算。为了得出较为精确的过流流量,按照重力相似准则制作几何比尺为1:5的模型进行试验研究。在已有自由出流公式的基础上,对自由出流流量系数进行修正并对淹没情况下流量变化过程进行研究。对该非标准堰自由出流流量系数的实测值与经验值进行分析比较,发现堰板槽降低了实际自由出流过流能力。淹没出流的流量系数主要和下游尾水位有关,试验中形成的淹没式堰流受实际堰型尺寸影响,下游尾水位和堰上水位近似相等,不完全适用已有淹没出流流量公式,通过试验给出了淹没流量系数随h/p的变化关系。结果表明利用堰前、堰后水位初步计算过流流量是可行的,可为该工程提供参考。也可为实际工程中非标准矩形堰的流量计算提供思路。
[Key word]
[Abstract]
There is a water retaining weir at the water intake of lingzhuangzi water plant, which is a non-standard thin-walled weir, so the existing weir flow formula cannot be used to calculate its flow. In order to get a more accurate discharge, a model with a scale of 1:5 was made according to the gravity similarity criterion. On the basis of the existing free outflow formula, the discharge coefficient is modified and the flow change process under the condition of inundation is studied. The measured value of the free outflow coefficient of the weir is compared with the empirical value, and it is found that the weir plate groove reduces the overflow capacity. The discharge coefficient of submerged outflow is mainly related to the downstream tail water level. The submerged weir flow formed in the test is affected by the size, and the downstream tail water level and the weir water level are approximately the same, which is not fully applicable to the existing formula of submerged discharge. The relationship between the submerged discharge coefficient and h/p is given by experiment. The results show that it is feasible to use the water level in front of and behind the weir to preliminarily calculate the discharge, which can provide a reference for the project. It can also provide ideas for flow calculation of non-standard rectangular weir in practical engineering.
[中图分类号]
TV132
[基金项目]
国家重点研发计划资助项目(2018YFC1508403)