Study Of Flow And Heat Transfer Of Liquid Metal LiPb Experimental Loop Testing Section Under Transverse Magnetic Field

The liquid metal LiPb(lithium-lead) blanket has been regarded as the primary research and design project in the world because of its complex geometry applicability, high tritium multiplication ratio, online access to tritium and replacing material facility and many other advantages in the study of fusion reactor blanket. However, owning to the harsh environment in which the magnetic confinement fusion reactor blanket and the exterior auxiliary system of fusion reactor works, the flow of liquid metal LiPb will bring a lot of challenging technical problems. For example, when the conductive liquid metal LiPb flow through the strong magnetic field, it can cause the MHD (magnetohydrodynamics) effect, which is caused by the interaction of conductive fluid and magnetic field. Moreover, this effect shall change the flow distribution of liquid metal LiPb in fusion blanket and lead to enormous MHD pressure drop and driving power. As a result, heat transfer efficiency of the blanket may be reduced. The liquid metal LiPb experimental loop is a very important experimental equipment that can create a fusion reactor conditions to study the compatibility, the flow characteristic and the MHD effects of liquid metal LiPb in the fusion blanket.This paper has done many researches on the liquid metal experiments loop at home and abroad, especially LiPb experimental loop. Based on the above preparation, a small experimental platform was designed according to the requirements of the experiment, on which the effect of nature and force convection on heat transfer in the liquid metal LiPb blanket can be studied. Besides, large commercial computation fluid dynamics software FLUENT was used to simulate nature convection of simplified model of 2D and 3D, and the numerical simulation results are basically consistent with design requirements. Ultimately, many pieces of advice on the selection and installation of pipe bend part in the loop was brought forward based on the deep analysis of velocity and temperature distribution.FLUENT's user-defined functions was used to modify related items of the momentum equation, energy equation and k-epsilon equation. Combined with magnetic field procedures in itself, the method of FLUENT MHD module was used to simulate the flow, heat transfer and MHD pressure drop of fluid in the circular and square of different wall material test pipe. Meanwhile, the MHD pressure drop of test pipe was calculated using of existing theoretical formula. And then, the computation results and the numerical simulation results would be compared with each other, and results show that the circular and square pipes can meet the test requirements. The above work has provided theory basic and design reference, so as to guide the loop experiment better.