SYMPTOMS OF STATES INCLUDED IN THE PERFORMANCE OF CON-ROD-PISTON COMBUSTION ENGINES SYSTEMS

Abstract

The following article describes energetic states symptoms, included in correct and incorrect performance of crankpiston combustion engines systems. Special attention has been paid to accompanying processes of such performance, with regard to, heat generation effect in combustion chamber and friction in joined frictional movements. Combustion chamber is a moving space formed by connection of the piston through piston rings with the cylinder liner and the engine head. Heat generation process takes place above the piston, generated by burning of fuel. It causes an increase of gas pressure in the combustion space, which results in the movement of the piston tightened by the rings, followed by an increase of the space volume. In this way energy is emitted from fuel burning, influencing the elements of piston-conrod system in the form of heat and work. The ability of such thermodynamical system to convert energy into an effective one is limited. Internal energy of exhaust gases can be divided into the part which cannot be converted into work. The process of heat generation in engine cylinder is of irreversible character which results in the loss of energy. In piston combustion engines, work is performed by heat generated in cylinders. Energetic performance in piston-crank system results from internal exchange of exhaust gases in combustion chamber with the engine surroundings. Analysis of such energetic performances allows us to isolate symptoms of correct operation of piston con-rod combustion engine systems. Such symptoms include: exhaust gases temperature, temperature of piston surface, momentary values of torque and the speed of pressure increase during combustion. Piston-con-rod system is a component part of the engine. Evaluation of its performance allows to identify the present technical condition of the engine. Diagnostic advantages of some, above mentioned symptoms of piston-con-rod combustion engine operation, have been verified by means of adequate laboratory testing and during engine operation on the ship.