Currently there is no way for the Client API to navigate to a different part of the sitemap.
There is an undocumented way of doing this:
viewId:"xxxxx", // Optional if you want a specific view
viewType:"1039" // Optional if you want a specific view
Please can we have this supported because using openUrl creates a very jarring UX for the user because a new window opens and the client browser back history is not maintained.
Wow - well that was quick!!