严重事故堆芯μ子成像监测重建方法研究

Muon Reconstruction Algorithm for Reactor Core Monitoring in Severe Accident

严重事故发生时,堆芯变化对于跟踪事故进程、确定应急方案十分重要。宇宙射线μ子成像监测技术具有高穿透力、对高原子序数物质敏感等特点,已被证明适用于核材料的监测。图像重建算法是实现这一技术的关键难点之一,由于待测目标物体为高原子序数物质,通常会在其周围伴随着灰度值相近的点状噪声。本文为提高重建质量,便于严重事故期间应急人员实时监测堆芯变化,提出了在径迹重建算法的基础上使用巴特沃斯滤波技术消除点状干扰的重建方法,初步模拟实验结果表明,该方法可有效降低噪声,从而验证了该方法的有效性。

When a severe accident happens,the dynamic change of the reactor core is particularly important for tracking accident progression and determining the emergency plan.The cosmic ray muon imaging technique is sensitive to high atomic number materials with high penetration,which has been demonstrated to be applicable for monitoring of nuclear materials.The reconstruction algorithm is a key point of this technique,and the detective object is usually accompanied by noises with the similar gray value for its high atomic number.In order to improve reconstruction quality for real-time monitoring the change of reactor core during a severe accident for emergency staffs,a reconstruction algorithm using POCA accompanied by Butterworth filter was proposed in this paper.The primary simulation result demonstrates that this algorithm which can obviouslyreduce the noise is effective.