Interaction of disk working body blade with foreign body during cutting of solid medium
Abstract
Flat disc knives are widely used in agriculture. The aim of this study is to analyze the interaction between a disc knife blade and foreign bodies - specifically plant residues in the soil – during the cutting of a continuous medium in various operating modes. The research employs a method of determining isogonal curves intersecting with a family of circles. The interaction of the disc knife blade with plant roots and residues (foreign bodies) is examined for the following operating modes of the disc knife: braked state disc rolling with sliding disc rolling without sliding disc rolling with slippage. When considering the interaction process between the disc knife blade and a foreign body, it was taken into account that the sliding of the foreign body along the blade is possible if the angle between the normal and the absolute velocity exceeds the maximum friction angle on the blade for the foreign body or the continuous medium being cut. Theoretical studies have yielded differential equations for isogonal trajectories, i.e. the movement paths of foreign body particles under the action of a disc knife blade, for various operating modes. Based on the analysis of the obtained equations for the movement trajectory of body particles under the action of the disc knife blade during continuous medium cutting, it was established that slowing the disc knife rotation, i.e. when the kinematic operating mode indicator (ratio of the circular speed of the disk knife to its translational speed) λ < 1 leads to its clogging with plant residues.