上游弯头对内锥流量计性能影响的仿真与实验研究

研究旨在获取上游弯头安装条件下内锥流量计的性能和所需要的直管段长度.研制了100mm口径、β值分别为0. 45、0. 65、0. 85三种结构类型的样机.开展了上游单弯头、同一平面上连续两个90°成S型结构双弯头及互成垂直平面上连续两个90°双弯头的仿真和实验研究,仿真和实验的介质均为常温水,雷诺数范围分别为0. 498×10~5~4. 98×10~5和0. 14×10~5~4. 5×10~5.仿真结果与实验结论一致,并利用平均流出系数相对误差及附加不确定度作为安装条件影响的主要评价标准.给出了上游弯头安装条件内锥流量计所需的直管段长度.

Simulative and experimental investigation on effect of upstream pipe elbow on the performance characteristics of cone flowmeters

In order to acquire the shortest straight pipe length and investigate the performance of cone flowmeter with installed upstream elbow, this study has put forward three different structure prototypes with lOOmm diameters and the p values being 0.45. 0.65. 0.85 respectively. Simulation and experiment investigations have been carried out with the installment of a upstream single 90o elbow, double closed 90o elbows of "S" shape under the same plane and double closed 90oelbows under the vertical plane, with the medium of normal temperature water and Reynolds numbers being 0.498 × 10~5 ～4.98 × 10~5 and 0.14 × 10~5 ～4.5 × 10~5 respectively. The numerical simulation result is consistent with the experimental conclusion. Through both of them, we ob-tain the length of the straight pipe for the cone flowmeter while the effects of the relative error and additive uncertainty of the averaged discharge coefficient on the installation of upstream el-bow have been considered.