Improvements in the Reliability and Efficiency of Body-fitted Cartesian Grid Method

In order to improve efficiency of the body-fitted Cartesian grid method and to make it possible to apply a geometry which includes complicated features such as small gaps, an extruded ghost surface is utilized. In the proposed approach, the grid front is generated by Cartesian grid generation over the ghost surface instead of the near-surface cell removal, which results in the faster turnaround and the flexibility to handle complicated geometry. By controlling length of an extrusion displacement vector, layer grid thickness, and by controlling grid resolution in a effective way such as sphere-type sources, an arbitrarily-shaped grid front can be obtained. As a result of this flexible capability to generate the arbitrarily-shaped grid front, body-fitted Cartesian grid method has been successfully extended to handle narrow gap problems. I.