Knock is an undesirable event that causes most of the abnormal combustion in spark ignition (SI) engines. In this paper, a novel knock intensity diagnosis method for SI engines by vibration analysis based on the ensemble empirical mode decomposition (EEMD) is proposed. First, the vibration signal measured from the test SI engine cylinder head is decomposed by the EEMD. Because the EEMD can elim...

Investigations were conducted to evaluate the performance of a two-stroke, single cylinder, spark ignition (SI) engine, with gasohol (80% gasoline and 20% ethanol by volume) having copper coated engine [CCE, copper-(thickness, 300 μ) coated on piston crown, inner side of cylinder head] provided with catalytic converter with different catalysts of sponge iron and manganese ore and compared with ...

Recent research in laser-induced ignition (LI) of air-fuel mixtures in internal combustion (IC) engines has shown there to be many potential advantages over conventional electrical spark ignition (SI). Spark plugs offer only limited possibilities for optimising engine efficiency, due to their fixed position within a cylinder and the protrusion of electrodes which disturb the cylinder geometry a...

Air-fuel control on turbocharged (TC) SI-engines require precise prediction of the cylinder air-charge (CAC). Using an observer it is possible to both estimate the necessary system states and to provide a framework to design the necessary CAC feedforward controller. Here a mean value engine model of a TC SI-engine is used to develop an observer. The output of the observer is fed as an initial c...

Nowadays, downsizing is a major way to reduce fuel consumption and pollutant emissions of Spark Ignition (SI) engines. In downsized engines, new air path management systems such as turbocharging or Variable Camshaft Timing (VCT) are including, and an efficient control of the air actuators is required for engine torque control. Two non-linear estimators are proposed to estimate non-measured vari...

A validation study is presented of a wrinkled-ame turbulent combustion model for SI engine simulation. Predictions using a multidimensional simulation code incorporating the model are compared with extensive measurements from a special optically-accessible engine, covering a range of speeds, loads, equivalence ratios and ignition timings. The agreement obtained is generally good and within the ...

Catalytic Decomposition of Biogas (CDB), producing simultaneously syngases (SG), with high hydrogen contents, for spark ignition (SI) engines and bio-carbon nanofibers (BCNFs) to be further used as precursor of synthetic graphite, is presented as an alternative to the usual direct combustion. Synthetic biogas mixtures were decomposed in the presence of a Ni catalyst at different temperatures an...

The spark timing plays a significant role in the combustion process and in deciding the engine parameters of SI engine. This paper aims at demonstrating the effect of advanced and retarded spark timing on the burn fraction variation versus crank angle, cumulative heat release rate versus the crank angle and the pressure variation as a function of crank angle with the help of MATLAB programs. Fo...