wake_strip

The wake_strip type (defined in wake_strip_mod) is a child class of mesh. It is a collection of vertices and panels defining the wake shed aft of a single wake-shedding edge. Each wake strip is only one set of panels wide. As such, it would probably be more intuitive to model these using quadrilateral panels, but quadrilateral panels are not implemented in MachLine.

The panels within a wake strip have only doublets, as sources necessarily induce a jump in pressure coefficient, which is not allowed on wake surfaces. In addition, the doublet strength is constant along the length of each wake strip. To achieve this, the vertices referenced in each panel belonging to the wake strip that define its doublet distribution are simply the vertices on the corresponding wake-shedding edge of the mesh. These are stored in the variables i_top_parent_1, i_top_parent_2, i_bot_parent_1, and i_bot_parent_2 for the strip, and in the variables top_parent and bot_parent for each vertex in the strip. When determining which vertices/strengths to use, the panel class will check whether it is in the wake, and use the appropriate indices.