I am not aware of a function shipped with org that jumps to the tangled file.
Furthermore, there is no separate function that generates the file name(s) for the tangled file(s) in `org-babel-tangle`. That makes the job a bit cumbersome.

The function `org-babel-tangle-jump` calls `org-babel-tangle` with `write-region` temporarily modified such that it does **not** write the region contents to a file but just delivers the file name that is passed to it in a  variable `file` locally bound in `org-babel-tangle-jump`. Finally, `org-babel-tangle-jump` opens the file with that name if it already exists.

<!-- language: lang-el -->

    (defun org-babel-tangle-jump ()
      "Jump to tangle file for the source block at point."
      (interactive)
      (let (file org-babel-pre-tangle-hook org-babel-post-tangle-hook)
        (cl-letf (((symbol-function 'write-region) (lambda (start end filename &rest _ignore)
    						 (setq file filename)))
    	      ((symbol-function 'delete-file) #'ignore))
          (org-babel-tangle '(4)))
        (when file
          (setq file (expand-file-name file))
          (if (file-readable-p file)
    	  (find-file file)
    	(error "Cannot open tangle file %S" file)))))