Analysis and interpretation of the kinematics of the reciprocating train according to the angular rotation of the crankshaft

Abstract

This paper presents the procedures used to measure and analyze the variation in the piston angular velocity of a 2000 cc internal combustion engine. In addition, the paper deals with important aspects of measuring displacement, acceleration and piston speed oscillations. The method is based on the development of a mathematical model to obtain the kinematic curves of behavior in the reciprocating train. The principle based on the geometries of the piston, connecting rod and crankshaft is also used to measure the actual angular velocity of the camshaft taking into account the 2 to 1 ratio, and this paper aims to demonstrate the possibility of measuring the actual angular velocity and acceleration of the piston according to the angular advance of the crankshaft. The method was created completely independently during research and development tests for internal combustion engines. This method is specific for its particular adaptability for use in power engines taking into account the geometry of the reciprocating train. The main objective of this article is to make a practical/theoretical contribution to all the most interesting research on the use of piston angular velocity as a diagnostic tool to identify irregular engine operation. The result of the analysis shows the behavior of the kinematics in a 2000 cc engine, verifying that each displacement, speed and acceleration generated based on the crankshaft rotation is directly or indirectly related to the behavior of the mentioned tests, effectively determining the influence of the environmental parameters on the function of each piston behavior acting on the entire piston, connecting rod and crankshaft segment.