Experimental and numerical study of the effect of injection strategy and intake valve lift on super-knock and engine performance in a boosted GDI engine

This paper explains about the evaluation of intake air flow, volumetric efficiency and noise of a motor-driven engine that used an adaptive valve lift and timing mechanism (AVLT) on one intake valve. This system is developed with an aim to produce a more powerful engine through variable valve timing and lift technique. The system made the valve lifts higher without increasing the valve lift duration. Therefore, a dynamic valve lift profile with respect to the engine speed can be achieved thus varies the input and output of an engine. As a result of applying the AVLT on a motor-driven engine, the engine noise, emission noise and the mass air flow entering the engine cylinder was increased. When AVLT is employed to a maximum lift, the mass air flow of default intake valve lift was improved within a range from 8% to 46.64% in 500 rpm to 2000 rpm speed range. Maximum lift produced engine noise within a range of 2.57% to 18.13% higher than the default lift throughout all speed. Also, maximum lift produced emission noise within a range of 2.47% to 19.19% higher than the default lift throughout all speed. The product of this research will be useful to optimise the height and timing of the valve lift and the AVLT mountings on the engine head during operation thus improves the engine performance, fuel economy, emission levels and reduced noise of a modified engine.

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The Effect of Intake Valve Lift on Turbulence Intensity and Burnrate in S.I. Engines-Model Versus Experiment

10.4271/840030 ◽

1984 ◽

Cited By ~ 19

Author(s):

G.C. Davis ◽

R.J. Tabaczynski ◽

R.C. Belaire

Keyword(s):

Turbulence Intensity ◽

Valve Lift ◽

Intake Valve ◽

Model Versus

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Numerical Study of Engine Performance and Emissions for Port Injection of Ammonia into a Gasoline\Ethanol Dual-Fuel Spark Ignition Engine

Applied Sciences ◽

10.3390/app11041441 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1441

Author(s):

Farhad Salek ◽

Meisam Babaie ◽

Amin Shakeri ◽

Seyed Vahid Hosseini ◽

Timothy Bodisco ◽

...

Keyword(s):

Numerical Study ◽

Combustion Process ◽

Engine Performance ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Combustion Model ◽

Dual Fuel ◽

Spark Ignition Engines ◽

Performance And Emissions ◽

Hc Emissions

This study aims to investigate the effect of the port injection of ammonia on performance, knock and NOx emission across a range of engine speeds in a gasoline/ethanol dual-fuel engine. An experimentally validated numerical model of a naturally aspirated spark-ignition (SI) engine was developed in AVL BOOST for the purpose of this investigation. The vibe two zone combustion model, which is widely used for the mathematical modeling of spark-ignition engines is employed for the numerical analysis of the combustion process. A significant reduction of ~50% in NOx emissions was observed across the engine speed range. However, the port injection of ammonia imposed some negative impacts on engine equivalent BSFC, CO and HC emissions, increasing these parameters by 3%, 30% and 21%, respectively, at the 10% ammonia injection ratio. Additionally, the minimum octane number of primary fuel required to prevent knock was reduced by up to 3.6% by adding ammonia between 5 and 10%. All in all, the injection of ammonia inside a bio-fueled engine could make it robust and produce less NOx, while having some undesirable effects on BSFC, CO and HC emissions.

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Analysis of Variable Intake Runner Lengths and Intake Valve Open Timings on Engine Performances

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.663.336 ◽

2014 ◽

Vol 663 ◽

pp. 336-341 ◽

Cited By ~ 4

Author(s):

Mohd Farid Muhamad Said ◽

Zulkarnain Abdul Latiff ◽

Aminuddin Saat ◽

Mazlan Said ◽

Shaiful Fadzil Zainal Abidin

Keyword(s):

Engine Performance ◽

Intake Manifold ◽

Intake Valve ◽

Si Engine ◽

Engine Simulation ◽

Engine Model ◽

Optimum Parameters ◽

Comparison Results ◽

Variable Valve ◽

Engine Development

In this paper, engine simulation tool is used to investigate the effect of variable intake manifold and variable valve timing technologies on the engine performance at full load engine conditions. Here, an engine model of 1.6 litre four cylinders, four stroke spark ignition (SI) engine is constructed using GT-Power software to represent the real engine conditions. This constructed model is then correlated to the experimental data to make sure the accuracy of this model. The comparison results of volumetric efficiency (VE), intake manifold air pressure (MAP), exhaust manifold back pressure (BckPress) and brake specific fuel consumption (BSFC) show very well agreement with the differences of less than 4%. Then this correlated model is used to predict the engine performance at various intake runner lengths (IRL) and various intake valve open (IVO) timings. Design of experiment and optimisation tool are applied to obtain optimum parameters. Here, several configurations of IRL and IVO timing are proposed to give several options during the engine development work. A significant improvement is found at configuration of variable IVO timing and variable IRL compared to fixed IVO timing and fixed IRL.

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Experimental research on pumping losses and combustion performance in an unthrottled spark ignition engine

Proceedings of the Institution of Mechanical Engineers Part A Journal of Power and Energy ◽

10.1177/0957650918754684 ◽

2018 ◽

Vol 232 (7) ◽

pp. 888-897 ◽

Cited By ~ 2

Author(s):

Tingting Sun ◽

Yingjie Chang ◽

Zongfa Xie ◽

Kaiyu Zhang ◽

Fei Chen ◽

...

Keyword(s):

Spark Ignition ◽

Spark Ignition Engine ◽

Valve Lift ◽

Combustion Characteristic ◽

Spark Ignition Engines ◽

Intake Valve ◽

Valve System ◽

Combustion Performance ◽

Intake Swirl ◽

Variable Valve

A novel fully hydraulic variable valve system is described in this paper, which achieves continuous variations in maximum valve lift, valve opening duration, and the timing of valve closing. The load of the unthrottled spark ignition engine with fully hydraulic variable valve system is controlled by using an early intake valve closing rather than the conventional throttle valve. The experiments were carried out on BJ486EQ spark ignition engine with fully hydraulic variable valve system. Pumping losses of the throttled and unthrottled spark ignition engines at low-to-medium loads are compared and the reason of it decreasing significantly in the unthrottled spark igntion engine is analyzed. The combustion characteristic parameters, such as cyclic variation, CA50, and heat release rate, were analyzed. The primary reasons for the lower combustion rate in the unthrottled spark ignition engines are discussed. In order to improve the evaporation of fuel and mix with air in an unthrottled spark ignition engine, the in-cylinder swirl is organized with a helical intake valve, which can generate a strong intake swirl at low intake valve lifts. The effects of the intake swirl on combustion performance are investigated. Compared with the throttled spark ignition engine, the brake specific fuel consumption of the improved unthrottled spark ignition engine is reduced by 4.1% to 11.2%.

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Simulation of Extended Expansion Lean Burn Spark Ignition Engine

ASME 2004 Internal Combustion Engine Division Fall Technical Conference ◽

10.1115/icef2004-0822 ◽

2004 ◽

Author(s):

A. Manivannan ◽

R. Ramprabhu ◽

P. Tamilporai ◽

S. Chandrasekaran

Keyword(s):

Heat Transfer ◽

Compression Ratio ◽

Thermal Efficiency ◽

Numerical Study ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Valve Closure ◽

Intake Valve ◽

Lean Burn ◽

Atkinson Cycle

This paper deals with Numerical Study of 4-stoke, Single cylinder, Spark Ignition, Extended Expansion Lean Burn Engine. Engine processes are simulated using thermodynamic and global modeling techniques. In the simulation study following process are considered compression, combustion, and expansion. Sub-models are used to include effect due to gas exchange process, heat transfer and friction. Wiebe heat release formula was used to predict the cylinder pressure, which was used to find out the indicated work done. The heat transfer from the cylinder, friction and pumping losses also were taken into account to predict the brake mean effective pressure, brake thermal efficiency and brake specific fuel consumption. Extended Expansion Engine operates on Otto-Atkinson cycle. Late Intake Valve Closure (LIVC) technique is used to control the load. The Atkinson cycle has lager expansion ratio than compression ratio. This is achieved by increasing the geometric compression ratio and employing LIVC. Simulation result shows that there is an increase in thermal efficiency up to a certain limit of intake valve closure timing. Optimum performance is attained at 90 deg intake valve closure (IVC) timing further delaying the intake valve closure reduces the engine performance.

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Simulation and experimental research of hydraulic pressure and intake valve lift on a fully hydraulic variable valve system for a spark-ignition engine

Advances in Mechanical Engineering ◽

10.1177/1687814018773156 ◽

2018 ◽

Vol 10 (5) ◽

pp. 168781401877315 ◽

Cited By ~ 2

Author(s):

Fei Chen ◽

Yingjie Chang ◽

Zongfa Xie ◽

Kaiyu Zhang ◽

Tingting Sun ◽

...

Keyword(s):

Experimental Research ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Valve Lift ◽

Hydraulic Pressure ◽

Intake Valve ◽

Valve System ◽

Variable Valve

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Diesel Engine Performance Improvement for Constant Speed Application Using CFD

Volume 7: Fluids Engineering ◽

10.1115/imece2017-70012 ◽

2017 ◽

Author(s):

Balasaheb S. Dahifale ◽

Anand S. Patil

Keyword(s):

Combustion Chamber ◽

Fuel Consumption ◽

Performance Improvement ◽

Test Data ◽

Engine Performance ◽

Exhaust Valve ◽

Fine Tuning ◽

Intake Valve ◽

Valve Seat ◽

Load Conditions

The detailed investigation of flow behavior inside the combustion chamber and performance of engine is most challenging problem due to constraints in Experimental Data collection during testing; However, Experimental testing is essential for establishment of correlation with CFD Predictions. Hence, the baseline engine was tested at different load conditions and validated with CFD results, before it was optimized for performance improvement. The objective of the CFD Prediction was not only to optimize performance (Fuel Efficiency, Power, Torque, etc.) & Emissions Reduction, but also to assess feasibility of Performance Upgrade Potential. In the present CFD study, surface mesh and domain was prepared for the flame face, intake valve, intake valve seat, exhaust valve, exhaust valve seat and liner for closed volume cycle, between IVC and EVO using CFD code VECTIS. Finally simulations for three different load conditions were conducted using VECTIS solver. Initially, in-cylinder pressure vis a vis crank angle prediction was carried out for 100%, 75% and 50% load conditions. Then the fine tuning of (P-ϴ) diagram for different load conditions was conducted by varying different combustion parameters. Further, the engine performance validation was carried out for rated and part load conditions in terms of, IMEP, BMEP, break specific fuel consumption and power output, while NOx mass fractions were used to convert the NOx to g/kWh for comparison of emission levels with the test data. Finally optimized re-entrant combustion chamber and modified valve timing with optimum fuel injection system simulation was carried out to achieve target performance with reduced fuel consumption. A 3D CFD result showed reduction in BSFC and was in close agreement with the test data.

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