Abstract: This invention relates to a rotary vane device and more particularly but not exclusively, to a rotary vane engine or pump. The invention also relates to a rotor assembly suitable for use in such a rotary vane device. The rotor assembly includes a cylindrical rotor body including a plurality of longitudinally extending receiving slots, the cylindrical rotor body further including a hollow core located radially inwardly of the receiving slots; and a plurality of vanes, with each vane being slidingly locatable inside a receiving slot. The rotor assembly is characterized in that the vanes are biased away from the cylindrical rotor by way of a magnet arrangement including vane magnets located in the vanes, and opposing rotor magnets located inside the hollow core of the rotor body.