Computational fluid dynamics modeling of submunition separation from missile

Original publisher: Aberdeen Proving Ground, MD : Army Research Laboratory, [1999] OCLC Number: (OCoLC)310979711 Subject: Computational fluid dynamics. Excerpt: ... in which h = At or ( At ) / 2 and the free stream base solution is used. Here, 6 is typically a three-point second order accurate central difference operator, 8 is a midpoint operator used with the viscous terms, and the operators 85 " a nd 6; are backward and forward three-point difference operators. The flux fi has been eigensblit, and the matrices 2, i, e, and & result from local Here, J denotes the Jacobian of the linearization of the fluxes about the previous time level. coordinate transformation. Dissipation operators De and Di are used in the central space differencing directions, 2.3 Chimera Scheme The chimera overset grid technique [ 7-91, which is ideally suited to multi-body problems, involves generating independent grids about each body and then oversetting them onto a base grid to form the complete model. This procedure reduces a complex multi-body problem into a An advantage of the overset grid technique is that it allows number of simpler sub-problems. computational grids to be obtained for each body component separately and thus makes the grid generation process easier. Because each component grid is generated independently, portions of Such points lie outside one grid may lie within a solid boundary contained within another grid. the computational domain and are excluded from the solution process. Equation 2 has been This i, modified for chimera overset grids by the introduction of the flag i, to achieve just that. array accommodates the possibility of having arbitrary holes in the grid. The i, array is defined so that i, = 1 at normal grid points and i, = 0 at hole points. Thus, when i, = 1, Equation 2 becomes the standard scheme, but when i, = 0, the algorithm reduces to A & ' = 0 or on + ' = on, leaving 0 unchanged at hole points. The set of grid points that forms the bo...