Follow the below steps to add Nastran Syntax file in vim editor.
1. Find out nastran.vim file location in your Linux system. In most of the cases, it will be located at /usr/share/vim/vim/syntax[version]/nastran.vim. This is file is installed from “vim-common” rpm.
2. Create Nastran filetype in your .vimrc file
au BufRead,BufNewFile *.bdf set filetype=Nastran