A positive displacement pump that consists of a chamber containing gears, cams, screws, vanes, plungers or similar elements actuated by relative rotation of the drive shaft or casing and which has no separate inlet and outlet valves.
A physical object intended to be used to collect and contain representative specimens or selections.
A thermodynamic turbine in which steam is made to do work by expanding so as to create kinetic energy by acting on moving blades attached to a disc or drum.
A physical object that is intended to rotate within a fluid and to transform energy within a fluid into mechanical power.