用LAHET和MCNP程序研究散裂中子靶的中子学性能

利用LAHET和MCNP程序对ADS散裂中子靶进行模拟计算。因靶的基本物理性质随束流和靶形状的变化而改变,所以首先评估了源强和靶的几何形状对靶性质的可能影响,然后计算长1.2m、直径为0.6m的圆柱形液态铅靶在1GeV质子轰击下,靶内中子的产生和泄漏及能量的沉积等。与文献数据、实验数据进行了比较,符合良好。计算结果还表明:源强和几何的选择对中子产生和泄漏可产生较大影响;用液态铅作散裂靶时,中子产额和泄漏额较高,且泄漏能谱在可利用范围内,但能量沉积在靶中的分布极不均匀,这可能给传热带来问题。

Study on Physical Characteristics of Spallation Neutron Target Using LAHET and MCNP Code

The spallation target of ADS was studied using LAHET and MCNP code. Since the basic physical properties of the target material vary according to the beam conditions and target geometry, the effects of beam condition and target geometry on the target properties were checked firstly. Then the simulating calculation of the lead target of 1.2 m length and 0.6 m in diameter bombarded with 1.0 GeV proton beam was (carried) out. The neutron production and leakage, energy deposition in the target were studied. The simulation results agree very well with the previous theoretical and experimental results. The calculations show that the energy of the incident proton and the target geometry make an important impact on the neutron production and leakage. For the given liquid Pb target, the neutron production and leakage are high and the leakage neutron spectrum shows to be good in the reactor. But energy deposition in the target is so inhomogeneous that it may be a challenge to the cooling of the target.