ABSTRACT

Overcoming the distortion appears in the production of fuel plate in Material Testing Reactor type (MTR) type fuel is considered an important challenge in safeguard measurements. A methodology is presented using a mathematical model and MCNP code to minimize defects that result from the chemical mixing in U₃O₈-Al Compact. The mathematical model relates between distance (sample – detector) and the count rate of 185.7 keV gamma energy line that characterize U-235 isotope. The tested samples are compact of uranium oxide and aluminum alloy. The mixing ratio is 48 volume % of U₃O₈, and 52 volume % of Al-metal powder. The sample volume is 35.48 cm³ and its density is 4.8 g/cm³. The manufacturer data concerning U-235 mass is 0.7785 and 21.3 g. The compact has a parallelpiped shape that has dimensions of 69, 8.5 and 60.5 mm. The used instrument is a High-Purity Germanium detector (HPGe) and the distances between the detector-sample are in the range from 9.5 to 11 cm. Results coming from the model and MCNP-5 complement each other and validated by comparing with declared values. The method could play an important role in safeguards and processes of Quality Control (QC) in the Fuel Manufacturing Pilot Plant (FMPP).

摘要

克服材料测试中燃料板生产中出现的变形，反应堆型（MTR）型燃料被认为是保障措施中的重要挑战。提出了一种使用数学模型和MCNP代码的方法，以最大程度地减少U ₃ O ₈ -Al压粉机中化学混合导致的缺陷。该数学模型在距离（样本-检测器）与表征U-235同位素的185.7 keV伽马能谱线的计数率之间建立了联系。所测试的样品是致密的氧化铀和铝合金。混合比例是U ₃ O _8的48体积％和Al金属粉末的52体积％。样品体积为35.48 cm ³，密度为4.8 g / cm ³。有关U-235质量的制造商数据为0.7785和21.3 g。压块具有平行六面体形状，尺寸为69、8.5和60.5 mm。使用的仪器是高纯锗探测器（HPGe），探测器样品之间的距离在9.5到11厘米之间。来自模型和MCNP-5的结果相互补充，并通过与声明值进行比较进行验证。该方法可能在燃料制造试验厂（FMPP）的质量控制（QC）的保障和过程中发挥重要作用。