how to volume mesh two surface mesh that are not enclosed?

Yes, you can make 'linear solid' between 2 surface mesh. In this case, two surface mesh should be 'similary': same nodes, same elements, same topology,....

thanks. How about the alignment option, it's a bit confusin...I was expecting it to ask if we choose x-xis or z axis

See attached screenshot.

Regards

Rahul R

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