Air flow quality analysis of modenas engine exhaust system

By analyzing the form of pressure wave within automotive exhaust system and relationship between propagation process and working condition of engine, simulate a work cycle for purpose of timely diagnosing troubles, thus presenting exhaust stroke of four cylinders through pressure wave; modifying of the speed of engine will affect the amplitude of pressure wave, harmonic components, phase position and other parameters; at the end of the exhaust stroke, exhaust pressure wave generates interference, superposition and negative effect, which is of great importance for analysis and diagnosis of engine troubles by using exhaust pressure wave.

Download Full-text

The Design and Analysis of Closed-Coupled Exhaust Manifold

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.215-216.1241 ◽

2012 ◽

Vol 215-216 ◽

pp. 1241-1245

Author(s):

Rang Shu Xu ◽

Xiang Feng Yan ◽

Ling Niu ◽

Zhi Wei Dong

Keyword(s):

Combustion Engine ◽

Catalytic Converter ◽

Exhaust System ◽

Flow Distribution ◽

Engine Exhaust ◽

Business Software ◽

Field Uniformity ◽

Calculation Results ◽

Cfd Method ◽

Volume Method

The layout of closed-couple catalyst converter in internal combustion engine exhaust system is one of important way to reduce vehicle emission. CFD method based on finite volume method is adopted to numerical simulate flow distribution in the entrance of closed-coupled catalytic converter and applying business software of FLUENT to clarity the flow uniformity of inlet to ensure catalytic converter work efficiently and meet regulations. The flow field uniformity of entrance were studied and analyzed. Research finds that the shape of manifold has effect on dispersion of velocity in entrance and dispersion of velocity has a relatively strong correlation with pulsation flow. The flow reverse in junction deflect the air flow that flow into the entrance of closed-couple catalyst converter. Calculation results indicate that the uneven rate coefficient is 0.266 and volatility is 0.515 in the entrance of closed-couple catalyst.

Download Full-text

Method and Device for Reducing the Toxicity of Diesel Engine Exhaust Gases

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.36.24922 ◽

2018 ◽

Vol 7 (4.36) ◽

pp. 920

Author(s):

Byshov N.V ◽

Bachurin A.N ◽

Bogdanchikov I.Yu ◽

Oleynik D.O ◽

Yakunin Yu.V. ◽

...

Keyword(s):

Diesel Engine ◽

Noise Level ◽

Alternative Fuels ◽

Exhaust System ◽

Exhaust Gas ◽

Engine Exhaust ◽

Exhaust Gases ◽

Gas Cleaning ◽

Cleaning System ◽

Exhaust Gas Cleaning

The aim of the article is to develop a method and a device for reducing the toxicity of exhaust gases of diesel engines and reducing noise taking into account the current mode of operation of the engine. This is done with the help of installing a liquid catalyst (LC) into the exhaust system, ensuring the processes of trapping, chemical bonding and neutralization of toxic components and soot particles in the aerosol chamber while the vortex flow is being processed by a neutralizing solution supplied under pressure. Then the flow is divided into phases and toxic components and soot are separated in the centrifugal swirl drop separator (SDS).The developed and tested design of an exhaust gas cleaning device installed instead of the standard D-120 engine exhaust system and an automated cleaning process control system make it possible to reduce the toxicity of exhaust gases (EG): nitrogen oxides by 40 %, hydrocarbons by 43 % and soot by 70 %. The noise level of its work in enclosed spaces was reduced by 16–22 %. The device also had low gas-dynamic resistance.The investigation methodology is based on the use of modern methods and measuring devices. Exhaust gas tester META “Autotest CO – CH – CO2 – O2 – λ – NOx” was used to measure the toxicity of exhaust gases. To measure smoking at the exhaust of the diesel engine, the opacity meter META-01MP was used. The gas flow velocity was measured with ATT-1004 thermo-anemometer, the noise level of the tractor was recorded with noise and vibration meter VSHV–003–M2, and the fuel consumption with SIRT-1 meter.Theoretical studies were carried out on the basis of the laws of gas dynamics, the modern theory of statistical analysis, and experiment planning techniques. When developing an experimental LC model, dependencies were obtained, which allow to achieve the optimal design and technological parameters of the wet cleaning system for diesel exhaust gases.The optimization of the design parameters and the processing of experimental data were carried out with the help of modern software using the methods of mathematical statistics using computers.The current methods of reducing the toxicity of engines consist primarily in improving the design of engines, in order to influence the nature of the working process, the use of alternative fuels and additives, exhaust gas recirculation, as well as installing various types of exhaust gas catalytic systems. Measures related to the introduction of constructive changes in engines require some major restructuring of the industry, which is difficult to achieve in modern conditions. Alternative fuels have not yet been widely used in agriculture. Therefore, today the most effective and acceptable means of achieving environmental standards is the installation of various mobile catalysts in the exhaust system, as well as devices for trapping soot particles. The use of this exhaust gas cleaning system for diesel engines functioning in enclosed spaces can significantly improve the working conditions of the personnel and have a slight effect on the power and fuel-economic performance of the power unit, reducing the power of the D-120 engine of the T-30 tractor equipped with an upgraded exhaust system when taking external speed characteristics averaged 1.6 %, the torque was 1.5 % and the increase in specific fuel consumption was 1.8 %.In this paper we used materials from scientific publications indexed by bibliographic abstract databases of Scopus and Web of Science.

Download Full-text

Paper 34: Effects of Variable Specific Heats and Gas Composition on Unsteady Flow Calculations

Proceedings of the Institution of Mechanical Engineers Conference Proceedings ◽

10.1243/pime_conf_1969_184_167_02 ◽

1969 ◽

Vol 184 (7) ◽

pp. 101-107 ◽

Cited By ~ 2

Author(s):

R. S. Benson ◽

A. Wild ◽

D. Woollatt

Keyword(s):

Pipe Wall ◽

Exhaust System ◽

New Method ◽

Gas Composition ◽

Perfect Gas ◽

Engine Exhaust ◽

One Dimensional ◽

Specific Heats ◽

Flow Problems ◽

Longitudinal Variations

A numerical method has been developed for the solution of one-dimensional non-steady flow problems including the effects of friction, gradual area change, heat transfer between the gas and the pipe wall, longitudinal variations, and discontinuities in gas composition and entropy. The fluid considered obeys the perfect gas equation of state, but the specific heats may vary with temperature. The method is not intended for use when shocks are present, but will give an approximate solution if shocks occur. The accuracy of the new method has been checked against existing methods for more simple cases, and although the new method has been found to be slightly superior it is more complicated, much slower, and the boundary conditions are more difficult to develop. For this reason, it is suggested that the new method be used to check on the adequacy of the existing simpler methods for each new application. The methods have been compared for the case of a typical diesel engine exhaust system and it has been found that the earlier methods are adequate for all practical purposes.

Download Full-text