Simulation analysis of 35 MeV high-power electron accelerator driven white neutron source target.

The white neutron source driven by an electron accelerator utilizes a pulsed electron beam to bombard a target, producing neutrons through photoneutron reactions. The white neutron source of photoneutron reaction has advantages such as compact structure, low cost, capability of generating ultra-short pulse, and wide applications in the resonance energy region, effectively complementing reactor neutron sources and spallation neutron sources. The development of high-current, high-power electron accelerator-driven white neutron sources is of significant importance for neutron science research and nuclear technology applications.

Numerical study of granular flow in a slit funnel with a novel structure to avoid particle clogging.

To solve the problem of particle clogging in slit funnels and to obtain a stable discharge flow rate, we proposed a new funnel structure, namely the slit baffle funnel. We conducted a systematic investigation using the discrete element method (DEM) to study the effects of funnel half-angle θ, outlet width W, and baffle height H on flow rate and flow pattern. We found that the proposed structure could effectively avoid particle clogging and guarantee a continuous and stable flow rate with small outlet width.

Flow-induced surface crystallization of granular particles in cylindrical confinement.

An interesting phenomenon that a layer of crystallized shell formed at the container wall during an orifice flow in a cylinder is observed experimentally and is investigated in DEM simulation. Different from shear or vibration driven granular crystallization, our simulation shows during the flow the shell layer is formed spontaneously from stagnant zone at the base and grows at a constant rate to the top with no external drive. Roughness of the shell surface is defined as a standard deviation of the surface height and its development is found to disobey existed growth models.

Preliminary research on flow rate and free surface of the accelerator driven subcritical system gravity-driven dense granular-flow target.

A spallation target is one of the three core parts of the accelerator driven subcritical system (ADS), which has already been investigated for decades. Recently, a gravity-driven Dense Granular-flow Target (DGT) is proposed, which consists of a cylindrical hopper and an internal coaxial cylindrical beam pipe. The research on the flow rate and free surface are important for the design of the target whether in Heavy Liquid Metal (HLM) targets or the DGT.