长塑料闪烁体核子料位计的研制

介绍了一种基于长塑料闪烁体的核子料位测量系统。根据射线穿过物料后强度衰减的原理,通过测定射线强度的变化确定料位的高度,分析了闪烁探测器的硬件结构,对塑料闪烁体两端以指数规律衰减的计数求加。闪烁探测器采用两端带有光电倍增管的长塑料闪烁体,并通过射随器和滞回比较电路增加探测信号带负载能力、滤除噪声和信号甄别。根据HND-S2塑料闪烁体的性能测试结果,建立探测器两端信号与点状放射源相对位置的关系,通过对其积分运算确定现场线状放射源理想模型来测定料位高度,其测量精度高误差低于1%,可广泛应用于石油、化工、医药等行业中。

Research on Nuclear Material Level Meter Based on Long Plastic Scintillator

A nuclear material level measurement system is introduced,which is based on the long plastic scintillator.According to the principle that the intensity of the rays attenuate after passing through substance,the height of the substance is determined by the change of the ray intensity.The hardware structure of the scintillation detector is analyzed.Both ends of the plastic scintillator counts decaying exponentially are summed.The both ends of long plastic scintillator with photomultiplier tube are used in the scintillation detector.The emitter follower and hysteresis comparator circuit increase the detection signal on load capacity,filter noise and discriminate signal.Relationship between the two ends signal of the detector and the relative position of the point-like radiation sources is established after the performance test results of HND-S2 plastic scintillator.According to the integration operation,the ideal model of the actual field of linear sources is determined,which is used to measure the height of the material level.The system has high measurement accuracy with an error of less than 1% and can be widely used in petroleum,chemical,pharmaceutical and other industries.