Fluid Mechanics


A large lawn sprinkler with four identical arms is to be converted into a turbine to generate electric power by attaching a generator to its rotating head, as shown in the below figure. Water enters the sprinkler from the base, along the axis of rotation, at a rate of 20 L/s and leaves the nozzles in the tangential direction. The sprinkler rotates at a rate of 300 rpm in a horizontal plane. The diameter of each jet is 1 cm and the normal distance between the axis of rotation and the center of each nozzle is 0.6 m. Note the relative motion between the jets and nozzles.