Diesel Precombustion Chamber Design and Its Influence on the Engine Performance and Exhaust Pollutants

The work presented in this paper compares the performance and emissions of the UBC “Squish-Jet” fast-burn combustion chamber with a baseline bowl-in-piston (BIP) chamber. It was found that the increased turbulence generated in the fastburn combustion chambers resulted in 5 to 10 percent faster burning of the air–fuel mixture compared to a conventional BIP chamber. The faster burning was particularly noticeable when operating with lean air–fuel mixtures. The study was conducted at a 1.7 mm clearance height and 10.2:1 compression ratio. Measurements were made over a range of air–fuel ratios from stoichiometric to the lean limit. At each operating point all engine performance parameters, and emissions of nitrogen oxides, unburned hydrocarbons, and carbon monoxide were recorded. At selected operating points a record of cylinder pressure was obtained and analyzed off-line to determine mass-burn rate in the combustion chamber. Two piston designs were tested at wide-open throttle conditions and 2000 rpm to determine the influence of piston geometry on the performance and emissions parameters. The UBC squish-jet combustion chamber design demonstrates significantly better performance parameters and lower emission levels than the conventional BIP design. Mass-burn fraction calculations showed a significant reduction in the time to burn the first 10 percent of the charge, which takes approximately half of the time to burn from 10 to 90 percent of the charge.

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Role of Precombustion Chamber Design in Feed-System Coupled Instabilities of Hybrid Rockets

Journal of Propulsion and Power ◽

10.2514/1.b37706 ◽

2020 ◽

Vol 36 (6) ◽

pp. 796-805

Author(s):

Jungpyo Lee ◽

Artur Elias De Morais Bertoldi ◽

Artem Andrianov ◽

Renato Alves Borges ◽

Carlos Alberto Gurgel Veras ◽

...

Keyword(s):

Feed System ◽

Precombustion Chamber ◽

Chamber Design ◽

Hybrid Rockets

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Combustion Chamber Design Effects on D.I. Common Rail Diesel Engine Performance

10.4271/2001-24-0005 ◽

2001 ◽

Author(s):

C. Beatrice ◽

P. Belardini ◽

C. Bertoli ◽

N. Del Giacomo ◽

Mna. Migliaccio

Keyword(s):

Diesel Engine ◽

Combustion Chamber ◽

Engine Performance ◽

Common Rail ◽

Design Effects ◽

Chamber Design

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Emission Reductions Through Precombustion Chamber Design in a Natural Gas, Lean Burn Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2906612 ◽

1992 ◽

Vol 114 (3) ◽

pp. 466-474 ◽

Cited By ~ 9

Author(s):

M. E. Crane ◽

S. R. King

Keyword(s):

Natural Gas ◽

Exhaust Emissions ◽

Hydrocarbon Emissions ◽

Oxides Of Nitrogen ◽

Lean Burn ◽

Precombustion Chamber ◽

Engine Efficiency ◽

Chamber Design ◽

And Control ◽

Total Hydrocarbons

A study was conducted to evaluate the effects of various precombustion chamber design, operating, and control parameters on the exhaust emissions of a natural gas engine. Analysis of the results showed that engine-out total hydrocarbons and oxides of nitrogen (NOx) can be reduced, relative to conventional methods, through prechamber design. More specifically, a novel staged prechamber yielded significant reductions in NOx and total hydrocarbon emissions by promoting stable prechamber and main chamber ignition under fuel-lean conditions. Precise fuel control was also critical when balancing low emissions and engine efficiency (i.e., fuel economy). The purpose of this paper is to identify and explain positive and deleterious effects of natural gas prechamber design on exhaust emissions.

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Precombustion Chamber Design and Performance Studies for a Large Bore Natural Gas Engine

ASME 2005 Internal Combustion Engine Division Spring Technical Conference ◽

10.1115/ices2005-1057 ◽

2005 ◽

Cited By ~ 7

Author(s):

Daniel B. Olsen ◽

Jessica L. Adair ◽

Bryan D. Willson

Keyword(s):

Natural Gas ◽

Performance Studies ◽

Engine Performance ◽

Precombustion Chamber ◽

Natural Gas Engines ◽

Natural Gas Engine ◽

Fuel Flow ◽

Spark Plug ◽

Lean Limit ◽

And Performance

Precombustion chamber (PCC) ignition is a common method for extending the lean limit and reducing combustion variability in large bore (36–56 cm) natural gas engines. An important component that commonly fails and requires regular replacement, besides the spark plug, is the checkvalve. The checkvalve meters fuel flow into the PCC. In this program the use of an electronic valve for monitoring fuel to the PCC instead of the checkvalve is investigated. Metering the fuel into the PCC with an electronic valve provides a number of different options for improving performance in addition to the benefit of extended valve life. PCC nozzle design is also evaluated as a means for improving PCC and engine performance. Additionally, emissions formation in the PCC is evaluated through the use of a separate pressure transducer in the PCC and a fast sample valve that extracts gas from the PCC.

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Application of Box-Behnken Analysis on the Optimisation of Air Intake System for a Naturally Aspirated Engine

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.17.2.2020.21.0602 ◽

2020 ◽

Vol 17 (2) ◽

pp. 8029-8042

Author(s):

N.S. Mustafa ◽

N.H.A. Ngadiman ◽

M.A. Abas ◽

M.Y. Noordin

Keyword(s):

Fuel Consumption ◽

Fuel Efficiency ◽

Engine Performance ◽

Fuel Price ◽

Design Expert ◽

Intake System ◽

Analysis Technique ◽

System Components ◽

Air Intake ◽

High Influence

Fuel price crisis has caused people to demand a car that is having a low fuel consumption without compromising the engine performance. Designing a naturally aspirated engine which can enhance engine performance and fuel efficiency requires optimisation processes on air intake system components. Hence, this study intends to carry out the optimisation process on the air intake system and airbox geometry. The parameters that have high influence on the design of an airbox geometry was determined by using AVL Boost software which simulated the automobile engine. The optimisation of the parameters was done by using Design Expert which adopted the Box-Behnken analysis technique. The result that was obtained from the study are optimised diameter of inlet/snorkel, volume of airbox, diameter of throttle body and length of intake runner are 81.07 mm, 1.04 L, 44.63 mm and 425 mm, respectively. By using these parameters values, the maximum engine performance and minimum fuel consumption are 93.3732 Nm and 21.3695×10-4 kg/s, respectively. This study has fully accomplished its aim to determine the significant parameters that influenced the performance of airbox and optimised the parameters so that a high engine performance and fuel efficiency can be produced. The success of this study can contribute to a better design of an airbox.

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Experimental and Numerical Analysis of a Motorcycle Air Intake System Aerodynamics and Performance

International Journal of Automotive and Mechanical Engineering ◽

10.15282/ijame.17.1.2020.10.0565 ◽

2020 ◽

Vol 17 (1) ◽

Author(s):

M. A. Abd Halim ◽

N. A. R. Nik Mohd ◽

M. N. Mohd Nasir ◽

M. N. Dahalan

Keyword(s):

Combustion Process ◽

Three Dimensional ◽

Engine Performance ◽

Internal Flow ◽

Rapid Expansion ◽

Navier Stokes ◽

Turbulent Fluctuation ◽

Ansys Fluent ◽

Induction System ◽

Acceleration And Deceleration

Induction system or also known as the breathing system is a sub-component of the internal combustion system that supplies clean air for the combustion process. A good design of the induction system would be able to supply the air with adequate pressure, temperature and density for the combustion process to optimizing the engine performance. The induction system has an internal flow problem with a geometry that has rapid expansion or diverging and converging sections that may lead to sudden acceleration and deceleration of flow, flow separation and cause excessive turbulent fluctuation in the system. The aerodynamic performance of these induction systems influences the pressure drop effect and thus the engine performance. Therefore, in this work, the aerodynamics of motorcycle induction systems is to be investigated for a range of Cubic Feet per Minute (CFM). A three-dimensional simulation of the flow inside a generic 4-stroke motorcycle airbox were done using Reynolds-Averaged Navier Stokes (RANS) Computational Fluid Dynamics (CFD) solver in ANSYS Fluent version 11. The simulation results are validated by an experimental study performed using a flow bench. The study shows that the difference of the validation is 1.54% in average at the total pressure outlet. A potential improvement to the system have been observed and can be done to suit motorsports applications.

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