This paper puts forward one kind of air-fuel ratio control method with PI controller. With the help of MATLAB/SIMULINK software, the mathematical model of air-fuel ratio control system for distributorless CNG engine is constructed. The objective is to maintain cylinder-to-cylinder air-fuel ratio at a prescribed set point, determined primarily by the state of the ThreeWay-Catalyst (TWC), so that...

The present study focuses on the effect of air-fuel ratio on the performance of four cylinder hydrogen fueled direct injection internal combustion engine. GT-Power was utilized to develop the model for direct injection engine. Air-fuel ratio was varied from rich limit to a lean limit. The rotational speed of the engine was varied from 1250 to 4500 rpm. The acquired results shown that the air fu...

Vehicle Emission is one of the main causes of environmental damage. Vehicle engines produce carbon dioxide (CO2), hydrocarbon (HC), Nitrogen oxides (NOx) and many other harmful substances. An investigation was conducted using a compression-ignition engine fuelled with different ratios of blends of diesel and biodiesel at different EGR rates. The effects of different ratios of fuel blends and EG...

A high pressure combined air-fuel injection system is designed and tested for an experimental free liquid-piston engine compressor. The application discussed utilizes available high pressure air from the compressor’s reservoir, and high pressure fuel to mix and then inject into a combustion chamber. This paper addresses the modeling, design and control for this particular high-pressure air-fuel...

In 4-stroke internal combustion engines, air-fuel ratio control is a challenging task due to the rapid changes of engine throttle, especially during transient operation. To improve the transient performance, managing the cycle-to-cycle transient behavior of the mass of the air, the fuel and the burnt gas is a key issue due to the imbalance of cyclic combustion process. This paper address the mo...

This paper describes active control of an aftertreatment system for a spark ignition engine equipped with a three-way catalyst and preand post-catalyst oxygen sensors. The control objective is to maximize the simultaneous conversion efficiencies of oxides of nitrogen and unburned hydrocarbons. Linear exhaust gas oxygen sensors are used to measure preand post-catalyst air-fuel ratio. A series co...

Respiratory Diseases are public health concern worldwide. The diseases have been associated with air pollution especially indoor air pollution from biomass fuel burning in developing countries. However, researches on pollution levels and on association of respiratory diseases with biomass fuel pollution are limited. A study was therefore undertaken to characterize the levels of pollutants in bi...

Maximization of the catalyst efficiency in automotive fuel-injection engines requires the design of accurate control systems to keep the air-to-fuel ratio at the optimal stoichiometric value AF . Unfortunately, this task is complex since the air-to-fuel ratio is very sensitive to small perturbations of the engine parameters. Some mechanisms ruling the engine and the combustion process are in fa...

Catalytic partial oxidation (CPOX) has recently received particular attention because it is one of the most attractive technologies for the production of syngas and hydrogen in small to medium scales. Current study subjected to partial oxidation reforming which have simultaneously studied the effect of the fuel composition and flow rates of methane-oxygen mixed gas on the SOFCs performances. In...

Air-fuel ratio control in gasoline engines has so far relied upon the fact that the stoichiometric air-fuel ratio of gasoline is an identified constant, largely thanks to its consistent chemical composition. In the case of Liquefied Petroleum Gas (LPG), chemical composition is subject to high variability due to geological and economic factors, amongst others. The implication of this variability...