[Gmsh] grouping surfaces into a surface loop and creating a volume generates unwanted surfaces

[Junhui Liu]

I have generated surfaces and decided to group them into a volume. 

unstructured_Volume_surfaces_array[] = Surface "*”;
Surface Loop(surf1) = {unstructured_Volume_surfaces_array[]};
volume_index = news;
Volume(volume_index) = {surf1};

Somehow duplicate surfaces appear and the indices of surfaces in the volume are not exact the same as I put inside the surface Loop. 
I generated 115 surfaces, but after I group them into a volume, the number of surfaces becomes 182. 

I used Gmsh 3.0.6, 1 with SetFactory("OpenCASCADE”);

I appreciate any help.

Junhui