Open AccessProcesses occurring in an engine with an unconventional duty cycle
Author(s) -
A. A Berdnikov
Publication year - 2017
Publication title -
izvestiâ mgtu "mami"
Language(s) - English
Resource type - Journals
eISSN - 2949-1428
pISSN - 2074-0530
DOI - 10.17816/2074-0530-66874
Subject(s) - four stroke engine , internal combustion engine , thermal efficiency , piston (optics) , two stroke engine , external combustion engine , cylinder , compression ratio , stroke (engine) , combustion , automotive engineering , thermodynamic cycle , mechanical engineering , internal combustion engine cooling , diesel cycle , stirling engine , engineering , combustion chamber , chemistry , physics , organic chemistry , optics , wavefront
An internal combustion engine is a thermal machine that converts thermal energy into mechanical energy. Currently, the existing engines operate in cycles of Otto, Diesel and Sabate-Trinkler. Such cycles are usually called traditional. As is known, traditional internal combustion engines do not have a high coefficient of efficiency due to large losses of heat with exhaust gases, heat removal to the cooling system, etc. The reserves of increasing the efficiency are very high. However, modern engine building has reached a high level and further improvement of the working process in traditional cycles is already ineffective. The article proposes a non-traditional seven-stroke internal combustion engine and examines the processes occurring in the cylinders of such an engine. In the main cylinder of the engine, the working cycle proceeds as in a traditional four-stroke internal combustion engine: at the first stroke, there is an intake, on the second stroke - compression, on the third - combustion and operating stroke, but in the fourth cycle the exhaust gases are not diverted from the cylinder, but are sent to an additional cylinder - there is a continued expansion of gases (operating stroke). At the fifth bar, the exhaust gases are compressed in an additional cylinder, and water is supplied at the end of the compression. Selecting heat from the heated parts of the cylinder-piston group and compressed gases, the water evaporates, and the expanding steam performs useful work (the sixth stroke is the operating stroke). At the seventh stroke, the piston moves to the top dead center, displacing the steam with the exhaust gases. Preliminary calculations showed that the maximum pressure of the seven-cycle operating cycle of the internal combustion engine can reach up to 20 MPa, this increases the power and fuel economy of the engine. The injection of water somewhat reduces the maximum cycle temperature and the toxicity of the exhaust gases. Such advantages give reason for the implementation of the working cycle of the internal combustion engine in a seven-cycle scheme.