Research of measurement of wet steam parameters with off-axis angular scattering method
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摘要: 为了实时监测汽轮机末级湿蒸气中水滴大小分布和浓度的变化，指导汽轮机的安全经济运行和锅炉给水量，减小湿蒸气对汽轮机的影响，提出了一种以CCD为探测器、测量湿蒸气参量的异轴角散射方法；根据模拟汽缸的结构和参量建立数学模型，并进行了仿真分析，得出水滴群质量中间半径、水滴数浓度和尺度分布参量的变化对散射比的影响规律；分别对不同工况下的湿蒸气进行了实验测量；仿真和实验结果变化趋势基本一致。结果表明，利用异轴角散射法测量湿蒸气参量变化是可行的。该研究对湿蒸气参量以及其它微粒的监测是有帮助的。Abstract: In order to monitor the density and distribution of water-drop at the end stage of the steam turbine, the off-axis angular scattering method was proposed to measure the parameters of wet steam. In this way, it not only guides economic operation of the turbine but also guarantee water allowance of the boiler. At the same time, it can reduce the influence of wet steam on the turbine. Based on the structure and parameters of mock cylinder, a mathematic model was built. This mathematic model can find whether the middle radius of quantity, the density of number and the distribution of magnitude in water-drop have impact on the scattering ratio. The wet steam was measured under different conditions. The analysis result was similar to the experimental result. The experimental results proved the off-axis angular scattering method is feasible for measuring wet steam parameters. This research is helpful for monitoring the parameters of wet steam and other particles.
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Keywords:
- scattering /
- wet steam parameter /
- off-axis angular scattering method /
- CCD /
- gray value
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