Design Of Online Maintenancs Device For Optical Units And Research On The Cleaning Condition

As the effective means to realize controllable nuclear fusion, inertial confinement fusion has become a high-tech development strategy in many countries. The host device of SG-â…¢ is the largest constructed inertial confinement fusion device in China, whose interior contains thousands of pieces of large-caliber optic elements. When the surface of optic element exists contaminant, the high energy laser may cause damage of optic element. The optic elements, which have been damaged, need maintenance and installation. Online maintenance device this paper designed can realize rapid installation of optic elements and prevent secondary pollution of the optic element, with the method of keeping positive pressure clean gas to achieve clean control in the process of maintenance.Firstly, the online maintenance plan was determined and the online maintenance device was designed after analyzing the structure characteristics of line-replaceable units(LRU) and online maintenance environment. The lightweight design of the cleaning container was finished for the maintenance process efficiency. The stiffness and strength of the support frame and the cleaning container was analyzed by using the finite element analysis software.Then the fluid simulation model was established based on computational fluid dynamics theory and the simulation principle of FLUENT software. The distribution of flow field in cleaning container and positive pressure clean gas were analyzed in terms of the effects for outside pollutant air.By simulating the movement of solid phase particles inside the cleaning container based air-solid two phase flow theory, the influence of clean gas inflow for clean condition was studied. Clean condition was obtained on different installation order of three crystal elements, with simulation analysis for different simulation model.Finally, the experiment project about keeping positive pressure clean gas to the cleaning container was designed. For different clean gas inflow, velocity distribution of fluid and particulate number retained in cleaning container were tested. The data from experiment verified the validity of the simulation model and the best clean gas inflow was obtained to achieve clean control.