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一种工作于严峻的温度或有放射性环境中的灵敏的液位传感器已在美国Sandia 国立实验室研制成功。根据原子能研究计划的需要进行开发的这种电子传感器能适于液位从几分之一英时到几英尺的较宽量程中使用。基本系统包括一个同轴电缆探头,局部浸在液体中,此探头与电子仪器和设备相连。被测液位由装在同轴传输电缆中的探头和一条基准线同时发送的电磁信号之特定值比较而确定。如果液位变化了,从探头反射到检测器的信号不同于从基准线反射到检测器的信号,仪器显示出液位的最终差别。1475°F液态钠的液位测量的研究是在一个模拟先进核反应堆芯体的条件下进行的。传感器能用于任何导电液体或任何高电容率的液体。一个典型的传感器系统包括一个产生从10到50MHz 量程频率的信号源。信号输送到分相器,在那里,信号被分解为两个在幅位和相位上精确平衡的两个新的信号。然后,其中一个信号直接通过同轴电缆作为基准线,而另一个通过同轴电缆的另一路与探头相连。
A sensitive level sensor operating in harsh temperatures or in a radioactive environment has been successfully developed at the Sandia National Laboratory in the United States. Such electronic sensors, developed to meet the needs of atomic energy research programs, can be adapted for use in a wide range of liquid levels from a fraction of an inch to a few feet. The basic system consists of a coaxial cable probe partially immersed in liquid and connected to electronics and equipment. The level of the fluid to be measured is determined by the comparison of specific values of the electromagnetic signals transmitted simultaneously by the probe mounted on the coaxial transmission cable and a reference line. If the level changes, the signal reflected from the probe to the detector differs from the signal reflected from the reference line to the detector and the instrument shows the final difference in level. The study of liquid level measurement at 1475 ° F in liquid sodium was performed under a simulated core condition of an advanced nuclear reactor. The sensor can be used with any conductive liquid or any liquid with high permittivity. A typical sensor system includes a signal generator that generates a range of frequencies from 10 to 50 MHz. The signal is fed to a phase splitter where the signal is split into two new signals that are precisely balanced in amplitude and phase. Then, one of the signals goes straight through the coaxial cable as the baseline and the other connects to the probe through another of the coaxial cables.