Full-Parameter Approach for the Intake Port Design of a Four-Valve Direct-Injection Gasoline Engine

2015 ◽  
Vol 137 (9) ◽  
Author(s):  
Lei Cui ◽  
Tianyou Wang ◽  
Zhen Lu ◽  
Ming Jia ◽  
Yanzhe Sun
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Gasoline Engine ◽  
Direct Injection ◽  
Critical Role ◽  
Intensity Change ◽  
Intake Port ◽  
Structure Parameters ◽  
Parametric Approach ◽  
Port Design

The design of the intake port plays a critical role in the development of modern internal combustion (IC) engines. The traditional method of the intake port design is a time-consuming process including a huge amount of tests and the production of core box. Compared with the traditional methods, parametric approach attracts increasing attentions by virtue of its high-efficiency, traceability, and flexibility. Based on a tangential port model created by a three-dimensional (3D) computer aided design (cad) software, a new tangential port can be quickly generated with different sets of structure parameters, then computational fluid dynamics (CFD) was employed to explore the influence of structure parameters on the intake port performance. The results show that the flow capacity and the large-scale vortex intensity change regularly with the variations of structure parameters. Finally, the parametric approach was employed to design the intake port of a production four-valve direct-injection (DI) gasoline engine, and the good applicability this approach is well illustrated.

Optimization of the intake port shape for a five-valve gasoline engine

2001 ◽  
Vol 215 (6) ◽  
pp. 739-746 ◽  
Author(s):  
K Lee ◽  
C Lee ◽  
Y Joo
Keyword(s):  
High Efficiency ◽  
Gasoline Engine ◽  
Three Dimensional ◽  
Design Guidelines ◽  
Design Parameters ◽  
Computer Assisted ◽  
Intake Port ◽  
Port Design ◽  
Visualization Experiments ◽  
Valve Engine

For the development of a high efficiency gasoline engine, the optimization of the intake port shape for a five-valve engine has been studied. Intake multivalve cylinder heads were manufactured by using a three-dimensional computer-assisted design program, and steady state flow experiments and flow visualization experiments have been performed with these cylinder heads. The five-valve engines, which have larger valve opening areas, have larger intake flowrates and higher tumble ratios than the four-valve engines. The effects of intake port design parameters of a five-valve engine on the intake flowrate and tumble were studied, and the design guidelines for the five-valve engines were established.

Flow and Mixture Distribution in a High-Speed Five-Valve Direct Injected Gasoline Engine

2006 ◽  
Vol 7 (2) ◽  
pp. 143-166 ◽  
Author(s):  
N Kampanis ◽  
C Arcoumanis ◽  
S Kometani ◽  
R Kato ◽  
H Kinoshita
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Gasoline Engine ◽  
Flow Instability ◽  
Direct Injection ◽  
Mixture Distribution ◽  
Direct Injection Engines ◽  
Planar Laser ◽  
Performance And Emissions ◽  
Cylinder Flow

The in-cylinder flow, spray dynamics, air-spray interaction, and fuel vapour distribution have been characterized in a motorcycle five-valve gasoline engine in terms of their effect on performance and emissions. A five-valve single-cylinder optical engine was employed which operated at speeds up to 3000 r/min in the close spacing configuration, with an early induction injection strategy using a centrally mounted swirl pressure atomizer. Particle image velocimetry, spray imaging in a spray chamber and in the engine, and planar laser-induced fluorescence revealed the importance of a strong and ordered in-cylinder flow for the efficient distribution of the liquid fuel throughout the cylinder volume and its complete evaporation prior to combustion, especially in the relatively low speed regime investigated. Furthermore, in the absence of a large-scale vortex structure during compression, incomplete mixing may still occur, resulting in mixture inhomogeneities and flow instability. Consequently, in contrast to port fuel injected engines, where good mixing could be achieved at high revolution rates, even with an unstructured flow, in direct injection engines an ordered flow structure is a prerequisite for efficient combustion and low exhaust emissions.

Study of Combustion Anomalies of H2-ICE With External Mixture Formation

2006 ◽  
Author(s):  
Stephen A. Ciatti ◽  
Thomas Wallner ◽  
Henry Ng ◽  
William F. Stockhausen ◽  
Brad Boyer
Keyword(s):  
Internal Combustion Engines ◽  
Large Scale ◽  
High Efficiency ◽  
Combustion Engine ◽  
Direct Injection ◽  
Combustion Process ◽  
Engine Performance ◽  
Internal Combustion ◽  
Hydrogen Combustion ◽  
Mixture Formation

Although hydrogen is considered one of the most promising future energy carriers, there are several challenges to achieving a “hydrogen economy,” including finding a practical, efficient, cost-effective end-use device. Using hydrogen as a fuel for internal combustion engines is seen as a bridging technology toward a large-scale hydrogen infrastructure. To facilitate high-efficiency, high-power-density use of hydrogen with near-zero emissions in an internal combustion engine, detailed analysis of the hydrogen combustion process is necessary. This paper presents thermodynamic results regarding engine performance and emissions behavior during investigations performed on a single-cylinder research engine fueled by pressurized gaseous hydrogen. Avoiding combustion anomalies is one of the necessary steps to further improve the hydrogen engine power output at high-load operation while, at the same time, reducing fuel consumption and emissions during part-load operation. The overall target of the investigations is an improved combustion concept especially designed for hydrogen-engine-powered vehicles. Future activities include performing optical imaging of hydrogen combustion by using an endoscope. We will also investigate supercharged external mixture formation, as well as hydrogen direct-injection operation.

Pilot-Scale System With Particle-Based Heat Transfer Fluids for Concentrated Solar Power Applications

2020 ◽  
Author(s):  
Christopher A. Bonino ◽  
Joshua Hlebak ◽  
Nicholas Baldasaro ◽  
Dennis Gilmore
Keyword(s):  
Heat Transfer ◽  
Large Scale ◽  
Heat Transfer Performance ◽  
High Efficiency ◽  
Solar Power ◽  
Critical Role ◽  
Heat Transfer Fluid ◽  
Process Unit ◽  
Transfer Performance ◽  
Concentrated Solar Power

Abstract Concentrated solar power (CSP) is a promising large-scale, renewable power generation and energy storage technology, yet limited by the material properties of the heat transfer fluid. Current CSP plants use molten salts, which degrade above 600°C and freeze below 220°C. A dry, particle-based heat transfer fluid (pHTF) can operate up to and above 1,000°C, enabling high-efficiency power cycles, which may enhance CSP’s commercial competitiveness. Demonstration of the flow and heat-transfer performance of the pHTF in a scalable process is thereby critical to assess the feasibility for this technology. In this study, we report on a first-of-a-kind pilot system to evaluate heat transfer to/from a densely flowing pHTF. This process unit circulates the pHTF at flowrates up to 1 tonne/h. Thermal energy is transferred to the pHTF as it flows through an electrically heated pipe. A fluidization gas in the heated zone enhances the wall-to-pHTF heat transfer rate. We found that the introduction of gas mixtures with thermal conductivities 4.6 times greater than that of air led to a 65% increase in the heat transfer coefficient compared to fluidization by air alone. In addition to the fluidization gas, the particle size also plays a critical role in heat transfer performance. Particles with an average diameter of 270 μm contributed to heat transfer coefficients that were up to 25% greater than the performance of other particles of the same composition in size range of 65 to 350 μm. The considerations for the design of an on-sun system are also discussed. Moreover, the collective work demonstrates the promise of this unique design in solar applications.

scholarly journals High Performance Computing and Analysis-Led Development of High Efficiency Dilute Opposed Piston Gasoline Engine

2017 ◽  
Author(s):  
Siddhartha Banerjee ◽  
Clayton Naber ◽  
Michael Willcox ◽  
Charles E. A. Finney ◽  
K. Dean Edwards
Keyword(s):  
High Performance Computing ◽  
High Performance ◽  
Large Scale ◽  
High Efficiency ◽  
Gasoline Engine ◽  
National Laboratory ◽  
Charge Motion ◽  
Oak Ridge ◽  
Light Load ◽  
Performance Computing

Pinnacle is developing multi-cylinder 1.2 L gasoline engine for automotive applications using high performance computing (HPC) and analysis methods. Pinnacle and Oak Ridge National Laboratory executed large-scale multi-dimensional combustion analyses at the Oak Ridge Leadership Computing Facility to thoroughly explore the design space. These HPC-led investigations show high fuel efficiency (∼46% gross indicated efficiency) may be achieved by operating with extremely high charge dilution levels of exhaust gas recirculation (EGR) at a light load key drive cycle condition (2000 RPM, 3 bar BMEP), while simultaneously attaining high levels of fuel conversion efficiency and low NOx emissions. In this extremely dilute environment, the flame propagation event is supported by turbulence and bulk in-cylinder charge motion brought about by modulation of inlet port flow. This arrangement produces a load and speed adjustable amalgamation of swirl and counter-rotating tumble which provides the turbulence required to support stable low-temperature combustion (LTC). At higher load conditions, the engine may operate at more traditional combustion modes to generate competitive power. In this paper, the numerical results from these HPC simulations are presented. Further HPC simulations and test validations are underway and will be reported in future publications.

scholarly journals High-Performance Computing and Analysis-Led Development of High Efficiency Dilute Opposed Piston Gasoline Engine

2018 ◽  
Vol 140 (10) ◽  
Author(s):  
Siddhartha Banerjee ◽  
Clayton Naber ◽  
Michael Willcox ◽  
Charles E. A. Finney ◽  
Dean K. Edwards
Keyword(s):  
High Performance Computing ◽  
High Performance ◽  
Large Scale ◽  
High Efficiency ◽  
Gasoline Engine ◽  
National Laboratory ◽  
Oak Ridge ◽  
Light Load ◽  
Brake Mean Effective Pressure ◽  
Performance Computing

Pinnacle is developing a multicylinder 1.2 L gasoline engine for automotive applications using high-performance computing (HPC) and analysis methods. Pinnacle and Oak Ridge National Laboratory executed large-scale multidimensional combustion analyses at the Oak Ridge Leadership Computing Facility to thoroughly explore the design space. These HPC-led investigations show high fuel efficiency (∼46% gross indicated efficiency) may be achieved by operating with extremely high charge dilution levels of exhaust gas recirculation (EGR) at a light load key drive cycle condition (2000 RPM, 3 bar brake mean effective pressure (BMEP)), while simultaneously attaining high levels of fuel conversion efficiency and low NOx emissions. In this extremely dilute environment, the flame propagation event is supported by turbulence and bulk in-cylinder charge motion brought about by modulation of inlet port flow. This arrangement produces a load and speed adjustable amalgamation of swirl and counter-rotating tumble which provides the turbulence required to support stable low-temperature combustion. At higher load conditions, the engine may operate at more traditional combustion modes to generate competitive power. In this paper, the numerical results from these HPC simulations are presented. Further HPC simulations and test validations are underway and will be reported in future publications.

Nursing professionals’ attitudes toward use of physical restraints in Styrian nursing homes Austria

Pflege ◽  
2019 ◽  
Vol 32 (1) ◽  
pp. 57-63
Author(s):  
Hannes Mayerl ◽  
Tanja Trummer ◽  
Erwin Stolz ◽  
Éva Rásky ◽  
Wolfgang Freidl
Keyword(s):  
Nursing Homes ◽  
Large Scale ◽  
Critical Role ◽  
Physical Restraint ◽  
Care Practice ◽  
Physical Restraints ◽  
Convenience Sample ◽  
Restraint Use ◽  
Positive Attitudes ◽  
Nursing Professionals

Abstract. Background: Given that nursing staff play a critical role in the decision regarding use of physical restraints, research has examined nursing professionals’ attitudes toward this practice. Aim: Since nursing professionals’ views on physical restraint use have not yet been examined in Austria to date, we aimed to explore nursing professionals’ attitudes concerning use of physical restraints in nursing homes of Styria (Austria). Method: Data were collected from a convenience sample of nursing professionals (N = 355) within 19 Styrian nursing homes, based on a cross-sectional study design. Attitudes toward the practice of restraint use were assessed by means of the Maastricht Attitude Questionnaire in the German version. Results: The overall results showed rather positive attitudes toward the use of physical restraints, yet the findings regarding the sub-dimensions of the questionnaire were mixed. Although nursing professionals tended to deny “good reasons” for using physical restraints, they evaluated the consequences of physical restraint use rather positive and considered restraint use as an appropriate health care practice. Nursing professionals’ views regarding the consequences of using specific physical restraints further showed that belts were considered as the most restricting and discomforting devices. Conclusions: Overall, Austrian nursing professionals seemed to hold more positive attitudes toward the use of physical restraints than counterparts in other Western European countries. Future nationwide large-scale surveys will be needed to confirm our findings.

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

The Potential of Photoelectrochemical Carbon Sinks

2018 ◽  
Author(s):  
Matthias May ◽  
Kira Rehfeld
Keyword(s):  
Global Warming ◽  
High Temperature ◽  
Greenhouse Gas ◽  
Large Scale ◽  
High Efficiency ◽  
Carbon Sink ◽  
Solar Fuels ◽  
Negative Emissions ◽  
Viable Approach ◽  
Low Sensitivity

Greenhouse gas emissions must be cut to limit global warming to 1.5-2C above preindustrial levels. Yet the rate of decarbonisation is currently too low to achieve this. Policy-relevant scenarios therefore rely on the permanent removal of CO<sub>2</sub> from the atmosphere. However, none of the envisaged technologies has demonstrated scalability to the decarbonization targets for the year 2050. In this analysis, we show that artificial photosynthesis for CO<sub>2</sub> reduction may deliver an efficient large-scale carbon sink. This technology is mainly developed towards solar fuels and its potential for negative emissions has been largely overlooked. With high efficiency and low sensitivity to high temperature and illumination conditions, it could, if developed towards a mature technology, present a viable approach to fill the gap in the negative emissions budget.<br>

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