Please see CFDread_PLOT3D. DVread_PLOT3D has been replaced. reads a multiblock Plot3D format data file
DVread_PLOT3D_mb reads a pair of files which describe a Plot3D data set. It reads that data into an array of fields; each field describes one block of the data set. The result can be operated on by any of the *_ARR array-of-fields macros.
The Multi_Block object contains the array of fields plus some additional information, including the number of blocks and the bounds of the data set.