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The pre-chamber ignition technology is a good solution that can make spark-ignition engines gradually more efficient. The novelty of the study is the testing of the pre-chamber jet ignition according to detailed air-fuel mixture range and fuel injection rates by combustion chambers. The main points in using this pre-chamber jet ignition were to observe the effect of reducing fuel consumption and emission formation. The tests were carried out for 0.80-1.80 lambda ranges and the pre-chamber injection/main chamber injection mass ratio ranges. A commercial RON 98 fuel was used at two ignition modes in tests for 5000 rpm high engine speed. At the pre-chamber jet ignition usage, the in-cylinder pressure for 1.00 lambda is overall 1.78% and 19.89% higher than the 0.80 lambda and the 1.80 lambda. The brake specific fuel consumption is about 8.67% lower than the spark-plug ignition usage at 0.80-1.20 lambda range. The HC formation is overall 8.12% lower than the spark-plug usage. The NOx formation for the spark-plug ignition is approximately 53.97% higher than the pre-chamber jet ignition usage as the temperature in-cylinder is high. The pre-chamber jet ignition was led to a much shorter flame development time and better combustion stability than the spark-plug. (C) 2020 Elsevier Ltd. All rights reserved.

The effects of ethanol and E85 usages on engine performance characteristics have been numerically investigated at a dual sequential spark ignition engine. The Honda L13A4 i-DSI (Intelligent-Dual Sequential Ignition) engine (intake-exhaust manifold connections, intake-exhaust lines, intake-exhaust valves, cylinder, cylinder head, piston, spark-plugs, throttle etc.) was modeled in Ricardo-Wave software for ethanol and E85 usages taking into account all components related to the engine. In the analysis, engine speeds ranging from 1000 rpm to 6000 rpm with an increment of 500 rpm, throttle angle ranging from 22.5° to 90° with an increment of 2.5°, 10.8:1 compression ratio, 0.9 air-fuel ratio were adjusted. In the 1-D model, performance maps were generated using the data obtained as a result of the analyzes. As a result of the study, E85 has been observed to perform better than ethanol usage for the Honda L13A4 i-DSI that the engine designed for the usage of gasoline.

The effects of the flame radius and flame propagation have been investigated at a sequential ignition engine with numerically. A single cylinder of the sequential ignition engine was modeled in STAR-CD/es-ice software for the gasoline usage taking into account all components related to the combustion chamber. The effect of flame on engine characteristics is the function of flame radius and flame thickness. In the numerical analysis, compression ratio is 10.8:1, air-fuel ratio is 1.2, ignition advance at 30-25 CAD, engine speed is 3000 rpm and the flame thickness is 0.0001 m were kept constant. The analysis, k-e RNG turbulence model, Angelberger wall interaction and G-equation combustion model were used and optimum flame radius value was determined. Three different analysis were carried out to determine the effect of the flame radius and the flame radius was changed to 0.0005 m, 0.0010 m and 0.0020 m, respectively. As a result of the study, images of flame formation and propagation were obtained for the time period up to the top dead center at the time of sequential ignition. The effects of flame radius on CO2 formation and NOx formation were evaluated. The net work area was obtained from the highest engine power and pressure-volume graph when the flame radius was 0.0010 m for the specified operating conditions.

5th International Conference on Transportation and Traffic Engineering (ICTTE) -- JUL 06-10, 2016 -- Univ Lucerne, Lucerne, SWITZERLAND Dogu, Yahya/0000-0003-0474-2899; YONTAR, AHMET ALPER/0000-0002-5453-5137 WOS: 000387184100056 In this study, a spark-ignition engine fuelled with gasoline and LNG was modelled in 1-D at wide open throttle by using Ricardo-Wave software. Different engine speeds ranging from 1500rpm to 4500rpm with an increment of 500rpm were studied to evaluate the effects of gasoline and LNG on engine performance and exhaust emissions. It is determined that LNG decreases engine performance and emissions as well, at especially high speeds.