PL EN Your account Create account

Registered articles list

Improving the effective efficiency of a spark ignition engine through the use of a fully independent valve control system

The charge exchange work of the SI engine reaches particularly high values at partial loads. Therefore, in this operating range of the engine, there are potential opportunities to increase the energy efficiency by reducing the charge exchange work. The article presents theoretical research of the proposed system of fully independent valve control (FIVC) of the SI engine. The analysis included controlling the movement of the intake valves, which results in adjusting the mass of the fresh load to the current engine load, as well as the movement of the exhaust valves, where the main aim is to keep the rest of the exhaust gases in the cylinder, i.e. the implementation of internal exhaust gas recirculation. The open theoretical Seiliger-Sabathe cycle with the commonly used classic throttle regulation of load (being a model of the processes taking place in the SI engine) is the reference cycle for the assessment of benefits and study of the effectiveness of obtaining work as a result of the application of the FIVC system. A comparative analysis of the effectiveness of the application of the proposed system was carried out based on the selected quantities: fuel dose, energy-stoichiometric parameter, cycle work, relative work of charge exchange and cycle efficiency. The use of a fully independent valve control system to regulate the SI engine load makes it possible to eliminate the throttle and thus reduce the charge exchange work, especially in the partial load range. Reducing the work of charge exchange then leads to an increase in internal and effective work, which in turn results in an increase in the effective energy efficiency of the motor operation. The best effects in terms of reducing the fuel dose and increasing the cycle efficiency for the FIVC system, compared to the system with classic throttle control (Seiliger-Sabathe theoretical open cycle), are obtained in the area of low and medium engine load.
Topic: Engine testing and modelling
Author: Zbigniew ┼╗mudka
Co-authors: Stefan Postrzednik