Numerical Simulation Methods Of Multiphasic Reactive Fluids

Numerical simulation of multiphase reactive flows plays a very important role in many fields of application research. It is an indispensable tool for defence, civilian and scientific research, such as design and damage assessment of military weapons and ammunition, prevention and mitigation of serious explosion disaster, high-speed propulsion technology, supernova explosions in Astrophysics and etc.This thesis mainly studies numerical simulation methods of multiphase re-active flows. A multiphase reactive flow refers to a multiphase flow containing chemical reactions, with different state parameters for corresponding phase ma-terials.This thesis first reviews the important progress and developments in numer-ical simulation of the reactive Eulerian equations and detonation, especially the historical development of multiphase reaction flows, from many aspects:numer-ical schemes, boundary processing, grid technology and boundary treatment.This thesis discusses traditional detonation theories in detail, such as the Chapman-Jouguet (CJ) model and Zeldovich-von Neumann-Doring (ZND) the-ory, and introduces the whole process of detonation, from the single transient response, to differentiating between the precursor shock and reaction zone, then to two-dimensional multiwave interaction and cells.For an ideal fluid, this thesis utilizes Godunov scheme combined with Harten-Lax-van Leer-Contact (HLLC) type Riemann solver to construct a corresponding numerical method, and applies it to one-and two-dimensional ideal detonation problems, stable and unstable. The results of the numerical simulation show that the constructed algorithm has a good stability, and can effectively capture the structural features of the detonation wave. This thesis also studies the application of the high-order moving mesh method in detonation fluid, and compares it with the generalized Riemann problem (GRP) method in accuracy.For a non-ideal fluid, this thesis mainly considers three cases:stiffened e- quation of state, Cochran-Chan (CC) equation of state and Jones-Wilkins-Lee (JWL) equation of state. For these non-ideal reaction flows, the thesis develops a method of physical quantities reconstruction of different materials by using temperature balance, pressure balance, and the relationship between the mixed density and densities of different materials, and the relationship between the mixed energy and the ones of multimaterial. By solving these equations, the thesis reconstructs the physical quantities of different substances within cells. With the HLLC solver mentioned previously, one can calculate every flux more accurately, and get ready for the next iteration. For solving the equations, a new and efficient method "moving tracking method" is proposed, with which one can get physical solutions efficiently.In this thesis, the constructed algorithms are applied to a number of one-and two-dimensional detonation reaction flow problems with ideal or non-ideal equa-tions of states. Numerical results show that the algorithms can clearly capture the structures and the details of detonation waves, and can accurately resolve the multiwave interactions, including the triple points. These all verify the validity and reliability of the algorithms.At the end of this thesis, the main work and features of this thesis are sum-marized, and possible focus and difficulties in the following work are prospected.