Research Of SMB And Alpha Particle Radial Transport

The deuterium-tritium fusion reactions on JET and TFTR devices have experi-mentally verified the feasibility of fusion reactions and made important attempts to es-tablish self-sustaining fusion devices.One important goal of the International Ther-monuclear Fusion Experimental reactor under construction is that the energy produced by the deuterium-tritium fusion reaction is more than 5 times that consumed by heat-ing plasma.The Chinese Fusion Engineering Testing Reactor will also carry out the deuterium-tritium fusion reaction and verify the technologies needed for the construc-tion of demonstration reactor(DEMO).The burning plasma physics is very important for the design of fusion reactor and the realization of efficient steady-state operation of fusion reaction.The steady-state operation of fusion devices requires efficient fuelling and heating methods.Supersonic molecular beam injection is one of the main fuelling methods.Alpha particle transport and alpha particle heating the background plasma are the key issue of burning plasma physics research.In this work,a one-dimensional multi-fluid radial transport code TPSMBI has de-veloped to study the radial transport of supersonic molecular beams injection fuelling and alpha particles micro turbulence transport.Firstly,a one-dimensional Supersonic molecular beam injection fuelling model is developed,which includes the main phys-ical processes in the supersonic molecular beam injection process:molecular decom-position,atom ionization,atom and ion charge exchange,etc.TPSMBI code has been developed based on the supersonic molecular beam injection model,and the effects of supersonic molecular beam injection flux,injection speed,injection gas temperature and effective molecular decomposition rate on supersonic molecular beam injection process have been studied.Then a micro turbulent transport model of alpha particles has been added in TPSMBI code to study alpha particles transport and the heating background plasma by alpha particles.In addition,the radiatiave damping of reversed shear Alfven eigenmodes has been studied by NOVA code,preparing for the subsequent study of al-pha particle transport excited by Alfven wave instability in reversed shear configuration.When the injection flux of supersonic molecular beam changes with constant injec-tion speed of supersonic molecular beam,the depth of supersonic molecular beam injec-tion and radial profile of plasma density change little.Keeping the supersonic molecular beam injection density constant and increasing the supersonic molecular beam injec-tion velocity can increase the supersonic molecular beam injection depth and shorten the time for the molecular density reaching a steady state.Supersonic molecular beam with better speed uniformity can be obtained by lowering the injection temperature of supersonic molecular beam.Lowering the molecular decomposition rate can signif-icantly increase the depth of supersonic molecular beam injection,and lowering the effective molecular decomposition rate may be the reason for the increase of the depth of low-temperature supersonic molecular beam injection containing clusters on HL-2A tokmak device.The transport loss of alpha particles caused by microscopic turbulent transport is very small,and most alpha particles become helium ash through slowing down progress.The diffusion of alpha particles in energy space can significantly reduce the radial transport level of alpha particles.Alpha particles provide more energy to the background plasma through coulomb collision than the heat transport loss of the core background plasma.The radiatiave damping of reversed shear Alfven wave increases approximately linearly with the increase of the torodial mode number.The contribution of fast particle to radiative damping is closely related to the ratio of fast particle pressure to plasma total pressure.Fast ions contributes to the radiation damping in the same level with thermal particles.Radiative damping rate of reversed shear Alfven eigenmodes is much higher than electron Landau damping rate,ion Landau damping rate and collision Landau damping rate for high torodial mode number.In this work,one-dimensional fluid transport code TPSMBI has been developed for studying burning plasma physics and coupled to ONETWO code.TPSMBI code can be used for rapidly calculating the combustion rate in burning plasma,alpha par-ticle transport,heating background plasma by alpha particle and other problems,and provides support for the design of fusion reactors.The experimental data related to su-personic molecular beam injection can also be analyzed with TPSMBI code to provide basis for optimizing supersonic molecular beam injection fuelling.