Generation of Computational Mesh for CFPD Simulations - Computational Fluid and Particle Dynamics in the Human Respiratory System - page 76

Fig. 4.4 An example of a body-fitted mesh for the 90 ◦ bend geometry and corresponding
computational geometry

In Fig. 4.4 , the transformation must be defined such that there is a one-to-one
correspondence between the rectangular mesh in the computational domain and
the curvilinear mesh in the physical domain. The algebraic forms of the governing
equations for the multiphase problems are carried out in the computational domain
which has uniform spacing of ξ and uniform spacing of η . Computed information
is then directly fed back to the physical domain via the one-to-one correspondence of
grid points. Because of the need to solve the equations in the computational domain,
they have to be expressed in terms of the curvilinear coordinates rather than the
Cartesian coordinates, which means that they must be transformed from ( x , y )to
( ξ , η ) as the new independent variables.

4.2.3 Multi-block Mesh

Block-structured or multiblock mesh is another special case of a structured mesh.
This is particularly effective for complicated shapes where it is difficult to apply a
single block. A multiblock mesh allows the computational domain to be subdivided
into topological blocks. In Fig. 4.5 , the mesh is assembled from a number of struc-
tured blocks attached to each other. Here, the attachments of each face of adjacent