Linear And Nonlinear Ion Temperature Gradient Driven Modes In Multi-ion Ingredient Plasmas

The tokamak plasma is a kind of complex system,which can be influenced by a series of instabilities.The plasma confinement can be stabilized or destabilized by some physical progress,such as magneto-hydro dynamical equilibrium and instabilities,impurity radiation,the anomalous transport of electrons and ions.In tokamak theories,it is a challenge to explain how the anomalous transport takes place.One of the reasons bases on the excitation of ion temperature gradient driven turbulence,and it has been a long time since ion temperature gradient became a very interesting research field.Linear and nonlinear multi-species ions temperature gradient driven modes is studied in my research work,in which fluid model is used as the major research method.The influence on some instabilities and stable structures caused by different ions and other plasma parameters is discussed.Firstly,the existence(also characters,research method,development) of ion temperature gradient driven mode is introduced,the major method of research and results are introduced in detail.Secondly,the fluid model and kinetic model are built to study the local linear ion temperature gradient driven mode in multi-ion ingredient plasmas.The condition of local linear instability is given while there are two kinds of ions.The growth rate of the instability due to the parameterηis also investigated.Thirdly,the basic fluid equations are used to investigate a kind of stable dipole rotational vortex structure which can be excited in the presence of multi-ion ingredients.The influence on vortex properties by the ratio of the densities of different ion species is also studied numerically.Fourthly,the temporal evolution of linear ion temperature gradient driven instability is investigated in the presence of cross-field shear flow.A new kind of nonlinear stable structure,the tripole vortex emerges in the shear flow back ground. The temporal evolution of secondary excitation near the vortex core is investigated numerically using the "Non modal method"(also called the "Bayly's method").Fifthly,the energy balance and energy conversion equations in the presence of multi-species ions are studied.The non local linear ion temperature gradient driven instability is investigated under the background of multi-species ions.The anomalous transport coefficient due to the ion temperature gradient driven turbulence is calculated using an empirical formula.