scholarly journals A Charge Possibility of an Unfueled Prechamber and Its Fluctuating Phenomenon for the Spark Ignited Engine

Energies ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 303
Author(s):  
Nyamsuren Gombosuren ◽  
Ogami Yoshifumi ◽  
Asada Hiroyuki
Keyword(s):  
Internal Combustion Engines ◽  
Soot Formation ◽  
Combustion Efficiency ◽  
Power Sources ◽  
Rich Mixture ◽  
Lean Combustion ◽  
Toxic Emissions ◽  
Fuel Delivery ◽  
Charge Flow ◽  
A Charge

The demand for internal combustion engines remains high for mobile power sources in all fields due to their low costs, running distance capacity, charging reliability, and heavy driving durability. However, air pollution, efficiency, and environmental factors make this more challenging. According to recent research, using a fueled prechamber can lead to lean combustion in the main chamber, resulting in increased efficiency, reduced fuel consumption, and reduced toxic emissions. However, difficulties in producing a fueled prechamber for commercial engines include mixture and soot formation problems in the limited space of the prechamber, and limited research on the charging possibility of the unfueled prechamber. A removable prechamber is advantageous for used vehicles because an engine redesign is not required. Therefore, we proposed to use an unfueled prechamber to enhance the lean burning efficiency of the spark ignited (SI) engine and explore the possibility of charging an unfueled, unscavenged prechamber with a fuel-rich mixture. Consequently, investigating the possibility of filling an unfueled prechamber with a fuel-rich mixture without additional fuel delivery or an air control system was the aim of this study. For this purpose, the charge flowrate of the centrally located unfueled prechamber is extensively investigated by using Computational Fluid Dynamics (CFD), through its design. As a result, a realizable charge flow was detected for the unfueled prechamber in two periods in the inlet and compression strokes. Most importantly, we found fluctuation phenomena in mass flow rates at the inlet stroke directing a charge flow of the richer mixture into an unfueled prechamber without additional systems. Moreover, keeping the charged rich mixture inside the prechamber during the compression stroke is as important as charging the prechamber with the fuel-rich mixture. The study will enable us to produce a removable prechamber to improve the combustion efficiency of port injected engines.

Experimental Evaluation of Turbo-Matching Appropriateness of B60J67, B60J68, A58N70 and A58N72 Turbo-Chargers for a Commercial Vehicle Engine

2018 ◽  
Vol 6 (11) ◽  
pp. 71
Author(s):  
Badal Dev Roy ◽  
R. Saravanan
Keyword(s):  
Internal Combustion Engines ◽  
Perfect Match ◽  
Engine Performance ◽  
Operating Conditions ◽  
Data Logger ◽  
Negative Effects ◽  
Road Test ◽  
The Road ◽  
A Charge ◽  
All Speeds

The Turbocharger is a charge booster for internal combustion engines to ensure best engine performance at all speeds and road conditions especially at the higher load.  Random selection of turbocharger may lead to negative effects like surge and choke in the breathing of the engine. Appropriate selection or match of the turbocharger (Turbomatching) is a tedious task and expensive. But perfect match gives many distinguished advantages and it is a one time task per the engine kind. This study focuses to match the turbocharger to desired engine by simulation and on road test. The objective of work is to find the appropriateness of matching of turbochargers with trim 67 (B60J67), trim 68 (B60J68),  trim 70 (A58N70) and trim 72 (A58N72) for the TATA 497 TCIC -BS III engine. In the road-test (data-logger method) the road routes like highway and slope up were considered for evaluation. The operating conditions with respect various speeds, routes and simulated outputs were compared with the help of compressor map.

scholarly journals Combustion Thermodynamics of Ethanol, n-Heptane, and n-Butanol in a Rapid Compression Machine with a Dual Direct Injection (DDI) Supply System

Energies ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2729
Author(s):  
Ireneusz Pielecha ◽  
Sławomir Wierzbicki ◽  
Maciej Sidorowicz ◽  
Dariusz Pietras
Keyword(s):  
Heat Release ◽  
Combustion Chamber ◽  
Internal Combustion Engines ◽  
Direct Injection ◽  
Combustion Process ◽  
Combustion Efficiency ◽  
Injection System ◽  
Rapid Compression Machine ◽  
Process Indicators ◽  
Rapid Compression

The development of internal combustion engines involves various new solutions, one of which is the use of dual-fuel systems. The diversity of technological solutions being developed determines the efficiency of such systems, as well as the possibility of reducing the emission of carbon dioxide and exhaust components into the atmosphere. An innovative double direct injection system was used as a method for forming a mixture in the combustion chamber. The tests were carried out with the use of gasoline, ethanol, n-heptane, and n-butanol during combustion in a model test engine—the rapid compression machine (RCM). The analyzed combustion process indicators included the cylinder pressure, pressure increase rate, heat release rate, and heat release value. Optical tests of the combustion process made it possible to analyze the flame development in the observed area of the combustion chamber. The conducted research and analyses resulted in the observation that it is possible to control the excess air ratio in the direct vicinity of the spark plug just before ignition. Such possibilities occur as a result of the properties of the injected fuels, which include different amounts of air required for their stoichiometric combustion. The studies of the combustion process have shown that the combustible mixtures consisting of gasoline with another fuel are characterized by greater combustion efficiency than the mixtures composed of only a single fuel type, and that the influence of the type of fuel used is significant for the combustion process and its indicator values.

scholarly journals Combustion and Deposition, Erosion, and Corrosion Tests of Coal Turbine Fuels

1985 ◽  
Author(s):  
C. Wilkes ◽  
R. Wenglarz ◽  
D. W. Clark
Keyword(s):  
Residence Time ◽  
Combustion Efficiency ◽  
Water Slurry ◽  
Lean Combustion ◽  
Coal Water Slurry ◽  
Unburned Hydrocarbons ◽  
Alternative Approaches ◽  
The Rich ◽  
Burning Coal ◽  
Distillate Fuel

This paper discusses the results obtained from the rich-quench-lean (RQL) combustion system running on distillate fuel and coal water slurry (CWS). Estimates of fuel bound nitrogen (FBN) yield indicate that rich lean combustion is successful in reducing the yield from coal water slurry fuel to between 8% and 12%. Some improvements in combustion efficiency are required when burning coal water slurry to reduce carbon monoxide and unburned hydrocarbons to acceptable levels. These improvements are achievable by increasing the lean zone residence time. Further testing is planned to investigate the effects of residence time in more detail. The planned deposition, erosion, and corrosion (DEC) testing will evaluate alternative approaches for protection from deposition, erosion, and corrosion of turbines operating with coal derived fuels.

Impact of Oxygen Enriched Air on High Intensity Combustion and Emission

2015 ◽  
Author(s):  
Ahmed O. Said ◽  
Ahmed E. E. Khalil ◽  
Daniel Dalgo ◽  
Ashwani K. Gupta
Keyword(s):  
Oxygen Concentration ◽  
Reaction Zone ◽  
Combustion Efficiency ◽  
Oxygen Enrichment ◽  
Chemiluminescence Intensity ◽  
Exhaust Temperature ◽  
Lean Combustion ◽  
Unstable Combustion ◽  
The Impact ◽  
Co Emission

The influence of oxygen enriched air-methane flame under non-premixed and premixed fuel-lean combustion conditions is examined with focus on the emission of NO and CO, combustor exit temperature (Texit), and distribution of OH* chemiluminescence intensity. A cylindrical combustor was used at combustion intensity of 36MW/m3.atm and heat load of 6.25 kW. Results are also reported with normal air (21% oxygen). Oxygen enrichment provided stable combustion operation at lower equivalence ratios than normal air and also reduced CO emission. Increase in oxygen concentration from 21% to 25% and 30% increased the NO and decreased CO emissions at all equivalence ratios examined. Using 30% O2 enriched air in premixed case showed NO emissions of 11.4 ppm and 4.6 ppm at equivalence ratios of 0.5 and 0.4, respectively. Oxygen enrichment also reduced CO emission to 38 ppm at equivalence ratio of 0.5. Operating the combustor with normal air at these equivalence ratios resulted in unstable combustion. OH* Chemiluminescence revealed increased chemiluminescence intensity with the reaction zone to shift upstream at increased oxygen concentration. The exhaust temperature of the combustor increased with oxygen enrichment leading to lower CO concentration and increased combustion efficiency. The oxidizer injected at higher velocities mitigated the impact of reaction zone to move upstream that helped to reduce significantly both the NO and CO emission specifically under non-premixed combustion.

The CFD Design and Optimisation of a 100 kW Hydrogen Fuelled mGT

2020 ◽  
Author(s):  
Cedric Devriese ◽  
Gijs Penninx ◽  
Guido de Ruiter ◽  
Rob Bastiaans ◽  
Ward De Paepe
Keyword(s):  
Combustion Chamber ◽  
Power Plants ◽  
Internal Combustion Engines ◽  
Cone Angle ◽  
Electricity Production ◽  
Design Parameters ◽  
Inlet Temperature ◽  
Large Power ◽  
Power Sources ◽  
The Impact

Abstract Against the background of a growing deployment of renewable electricity production, like wind and solar, the demand for energy storage will only increase. One of the most promising ways to cover the medium to long-term storage is to use the excess electricity to produce hydrogen via electrolysis. In a modern energy grid, filled with intermittent power sources and ever-increasing problems to construct large power plants in densely populated areas, a network of Decentralised Energy Systems (DES) seems more logical. Therefore, the importance of research into the design of a small to medium-sized hydrogen fuelled micro Gas Turbine (mGT) unit for efficient, local heat and electricity production becomes apparent. To be able to compete with Reciprocating Internal Combustion Engines (RICEs), the mGT needs to reach 40% electrical efficiency. To do so, there are two main challenges; the design of an ultra-low NOX hydrogen combustor and a high Turbine Inlet Temperature (TIT) radial turbine. In this paper, we report on the progress of our work towards that goal. First, an improvement of the initial single-nozzle swirler (swozzle) combustor geometry was abandoned in favour of a full CFD (steady RANS) design and optimisation of a micromix type combustion chamber, due to its advantages towards NOx-emission reduction. Second, a full CFD design and optimisation of the compressor and turbine is performed. The improved micromix combustor geometry resulted in a NOx level reduction of more than 1 order of magnitude compared to our previous swozzle design (from 1400 ppm to 250 ppm). Moreover, several design parameters, such as the position and diameter of the hydrogen injection nozzle and the Air Guiding Panel (AGP) height, have been optimized to improve the flow patterns. Next to the combustion chamber, CFD simulations of the compressor and turbine matched the 1D performance calculations and reached the desired performance goals. A CFD analysis of the impact of the tip gap and exhaust diffuser cone angle led to a choice of these parameters that improved the compressor and turbine performance with a limited loss in efficiency.

Rapid Prototyping for Optimization of the Charge Motion in Internal Combustion Engines Driven by Sewage Gas

2019 ◽  
Vol 141 (12) ◽  
Author(s):  
Lucas Konstantinoff ◽  
Thomas Steiner ◽  
Dominik Mairegger ◽  
Guenther Herdin ◽  
Martin Pillei ◽  
...  
Keyword(s):  
Rapid Prototyping ◽  
Cylinder Head ◽  
Internal Combustion Engines ◽  
Test Bench ◽  
Positive Impact ◽  
Combustion Engine ◽  
Combustion Process ◽  
Charge Motion ◽  
Lean Combustion ◽  
Static Flow

Abstract This paper presents a newly developed method using rapid prototyping (RP) to develop gas engine cylinder heads with optimized charge motion characteristics to adapt to lean-burn and Miller combustion process requirements. The geometry in close vicinity to the inlet valve seats was designed to increase swirl and flow performance of the cylinder heads. A three-dimensional (3D) printer was used to realize a rapid prototyping concept for the testing of multiple designs; the effects of the different designs were measured using a static flow test bench and a laser-optical method to visualize the flow patterns. The results of the static flow bench tests showed potentially higher flow and swirl performance, with one high-swirl version proving beneficial specifically for lean-combustion and one high-flow version matching the Miller combustion requirements. The two cylinder head versions were then manufactured and the lean-combustion version was tested for on-engine performance on a 150 kW sewage-gas driven lean-combustion engine. It has been shown that the cylinder head generates higher swirl on the test bench but achieves only a slight increase in combustion speed on the test engine. The potential to increase engine efficiency by intensifying swirl is, therefore, considered exploitable. Research has further shown the coefficient of variance (CoV) was reduced by 0.3–1.2%. Charge exchange losses have also been demonstrated to decrease at all tested engine settings. It has further been found that higher swirl intensity has a positive impact on engine emission levels, as the engine out carbon monoxide (CO) emission can be reduced by approximately 70 mg·m−3.

A Simple Combustion Efficiency Indicator for Automobile Engines

1973 ◽  
Vol 6 (10) ◽  
pp. 399-400 ◽  
Author(s):  
M. S. Bolton ◽  
D. S. Taylor
Keyword(s):  
Carbon Monoxide ◽  
Internal Combustion Engines ◽  
Fuel Mixture ◽  
Internal Combustion ◽  
Combustion Efficiency ◽  
Exhaust Emission ◽  
Combustion Engines ◽  
Widespread Application ◽  
Mixture Ratio ◽  
Automobile Engines

A cheap device which can indicate carbon monoxide levels in exhaust emission of internal combustion engines, and hence could be used for adjusting the engine's operating air: fuel mixture ratio, would have widespread application in garages, etc. The instrument described here is sensitive to both unburnt hydrocarbons and carbon monoxide but measures the carbon monoxide to an accuracy well within the tuning capability of most carburation systems.

Reduction in NOx and CO Emissions in Stoichiometric Diesel Combustion Using a Three-Way Catalyst

2010 ◽  
Vol 132 (7) ◽  
Author(s):  
Junghwan Kim ◽  
Rolf D. Reitz ◽  
Sung Wook Park ◽  
Kian Sung
Keyword(s):  
Gasoline Engine ◽  
Injection Pressure ◽  
Combustion Efficiency ◽  
Boost Pressure ◽  
Nox Emissions ◽  
Diesel Combustion ◽  
Simultaneous Reduction ◽  
Lean Combustion ◽  
Numerical Studies ◽  
Three Way Catalyst

Experimental and numerical studies were performed to investigate the simultaneous reduction in NOx and CO for stoichiometric diesel combustion with a three-way catalyst. A single-cylinder engine was used for the experiments and KIVA simulations were used in order to characterize the combustion efficiency and emissions of throttled stoichiometric diesel combustion at 0.7 bar boost pressure and 90 MPa injection pressure. In addition, the efficiency of emission conversion with three-way catalysts in stoichiometric diesel combustion was investigated experimentally. The results showed CO and NOx emissions can be controlled with the three-way catalyst in spite of the fact that CO increases more at high equivalence ratios compared with conventional diesel combustion (i.e., lean combustion). At a stoichiometric operation, the three-way catalyst reduced CO and NOx emissions by up to 95%, which achieves lower emissions compared with conventional diesel combustion or low temperature diesel combustion, while keeping better fuel consumption than a comparable gasoline engine.

Piston ring–liner lubrication and tribological performance evaluation: A review

2017 ◽  
Vol 232 (2) ◽  
pp. 193-209 ◽  
Author(s):  
Cristiana Delprete ◽  
Abbas Razavykia
Keyword(s):  
Internal Combustion Engines ◽  
Piston Ring ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Combustion Engines ◽  
Power Losses ◽  
Oil Consumption ◽  
Major Power ◽  
Power Sources ◽  
Engine Efficiency

Internal combustion engines are at present used as the major power sources for transportation and power generator. Improvement of the internal combustion engine efficiency is expected due to strict environmental standards and energy costs. Any reduction in oil consumption, friction power losses and emissions results in improving engines’ performance and durability. Automotive industries have intense passion to increase engines’ efficiency to meet the fuel economy and emission standards. Many studies have been conducted to develop reliable approaches and models to understand the lubrication mechanisms and calculate power losses. This review paper summarizes the synthesis of the main technical aspects considered during modeling of piston ring–liner lubrication and friction losses investigations. The literature review highlights the effects of piston ring dynamics, components geometry, lubricant rheology, surface topography and adopted approaches, on frictional losses contributed by the piston ring-pack.

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