| 摘要: |
| 【目的】推求双曲线型薄壁堰堰流的基本方程式，确定双曲线型薄壁堰的流量系数，为实际工程中流量的控制和测量提供参考。【方法】根据双曲线构建了双曲线型薄壁堰，通过能量方程式推导其流量的计算公式；数值模拟了4种不同堰顶水头的过流能力，根据模拟的流量数据利用最小二乘法拟合流量与堰顶水头的关系式，与理论推求的堰流基本公式相结合确定双曲线型薄壁堰的流量系数，辅以RNG k-ε湍流模型数值求解气液两相流时均方程；使用半隐式SIMPLE（Semi-implicit method for pressure-linked equations）算法求解速度与压力耦合方程组，并用VOF（Volume of fluid）法模拟自由水面。【结果】理论公式计算的流量与数值模拟的流量相差甚微，相对误差在0.3％以内，证明本研究推求公式正确。【结论】双曲线型薄壁堰的流量与堰顶水头成正比关系，该关系为流量的控制和测量提供了便利。 |
| 关键词: 双曲线型薄壁堰 流量系数 数值模拟 流量公式 |
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| 基金项目:国家自然科学基金项目(51578452，51178391)；陕西省科学研究计划资助项目(2014K15-03-05)；陕西省工业科技攻关项目（2016GY-180） |
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| Numerical simulation of discharge of a hyperbolic weir |
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WEI Wenli,ZHANG Zewei,BAI Zhaowei,et al
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| Abstract: |
| 【Objective】A theoretical formula for calculating the discharge rate of a hyperbolic thin-walled weir was derived and its flow coefficient was determined to provide reference for controlling and measuring the flow rate in actual project.【Method】Based on the hyperbolic curve,a hyperbolic weir was constructed and the formula was derived by energy equation.The flow capacity under four different water heads over the crest was simulated.According to the simulated discharge rates,the relationship between discharge rate and corresponding water head over crest was obtained using the least square method.By comparing with the theoretical formula for discharge rate,the flow capacity coefficient of the hyperbolic weir was determined.The gas-liquid two-phase time-averaged equations were then solved with the help of RNG k-ε turbulence model.The coupling velocity and pressure equations were solved using the SIMPLE (Semi-implicit method for pressure-linked equations） algorithm and VOF (Volume of fluid) method was applied to track the flow surface.【Result】The difference in discharges between the numerical simulation and the theoretical formula was small with relative error of less than 0.3%,indicating that the theoretical formula was correct.【Conclusion】The flow discharge rate of the hyperbolic weir was proportional to the water head,which makes it easy to control and measure flow rate. |
| Key words: hyperbolic weir flow coefficient numerical simulation discharge formula |
