On the nature of idling noise of circular saw blades

Abstract An experimental investigation of the effects of important saw blade geometric and kinematic parameters on idling circular saw noise was conducted. Blade tip speed was determined t0 be the dominant factor in the noise production. The sound power generated was found to vary approximately as the 5·3 power of the tip velocity. Variations in blade geometry, which included the number of teeth, the blade thickness, and the tooth-gullet shape, produce effects in the radiated sound of the order of 6 dB for the blades tested. It is shown that slotted disks may be used to provide a closely controlled simulation of the saw blade noise produced aerodynamically. Results suggest that the sources are likely to be compact and are dominated by the unsteady forces acting on the tooth surfaces resulting from the interaction 0f the tooth and the incident unsteady flow in the wake of the preceding tooth.