【摘要】：為能夠快速評判實驗測試方案和預(yù)估實驗結(jié)果,建立了中子體通量的快速估算模型。理論上,封閉空間中子平均體通量與特征長度的平方成反比,且中子體通量的大小能反映散射中子注量強弱。采用蒙特卡羅模擬方法,計算得到了密閉實驗大廳內(nèi)中子的體通量,以及不同位置處的散射中子注量,并將模擬得到的體通量和散射中子注量擬合成便于工程實踐中應(yīng)用的解析表達(dá)式,擬合結(jié)果與模擬結(jié)果的相對偏差小于10%。研究結(jié)果表明,球形空間內(nèi)中子的體通量與球半徑的1.905次方成反比;密閉實驗大廳的中子體通量與大廳橫截面寬度的1.948次方成反比,與長寬比的0.775次方成反比;球形空間結(jié)構(gòu)內(nèi),每個源中子的平均徑跡長度約為半徑的5.4倍,而長方體密閉實驗大廳內(nèi),單個源中子的平均徑跡長度為大廳特征尺度的2~3倍。
[Abstract]:In order to evaluate the experimental test scheme and predict the experimental results quickly, a rapid estimation model of neutron flux is established. In theory, the average volume flux of neutrons in closed space is inversely proportional to the square of the characteristic length, and the flux of neutrons can reflect the intensity of scattered neutrons. By using Monte Carlo simulation method, the bulk flux of neutrons in the closed experimental hall and the amount of scattered neutrons at different positions are calculated. The simulated volume flux and scattered neutron flux are simulated to synthesize the analytical expressions which are convenient for application in engineering practice, and the relative deviation between the fitting results and the simulation results is less than 10%. The results show that the volume flux of neutrons in spherical space is inversely proportional to the 1.905 power of the radius of the sphere, and the flux of neutrons in the closed experimental hall is inversely proportional to the 1.948 power of the cross section width of the hall and inversely proportional to the 0.775 power of the aspect ratio. In the spherical spatial structure, the average track length of each source neutrons is about 5.4 times of the radius, while in the cuboid closed experimental hall, the average track length of a single source neutrons is 2 鈮，

本文編號：2477638