Development of Air-Cooled Cylinder Utilizing Baffle Plates between Fins with Cooling Ports 2007-32-0061

Several techniques facilitate the cooling of air-cooled motorbike engines. Baffle plates, mounted between cooling fins symmetrically with respect to a plane through the axis of the cylinder, maximize the distance that the cooling air follows the cylinder surface before it separates from the cylinder, when the motorbike is in motion. Cooling ports, drilled in the fins parallel to the axis of the cylinder, induce natural convection in the cylinder, when the motorbike is stationary. We produced cylinders with baffle plates between the fins, and with cooling ports, in order to improve cylinder cooling while motorcycles are both moving and stationary. We investigated experimental cylinders with baffle plates, cylinders with fins with cooling ports, and cylinders with both baffle plates and fins with cooling ports, all over a range of air velocities between 0 and 60 km/h. Results indicated that the cylinder with baffle plates was cooler than the cylinder without baffle plates, at air velocities between 20 and 60 km/h. Furthermore, the cylinder with fins with as many cooling ports as possible in the rear was cooler than a cylinder without cooling ports, at all air velocities. Finally, the cylinder with both baffle plates and fins with as many ports as possible in the rear had the greatest improvement in cooling at all air velocities.