Experimental analysis and comparison of performance characteristics of catalytic converters

The purpose of this chapter is to present the results of an experimental study of the performance and conversion efficiencies of ceramic monolith three-way catalytic converters (TWCC) employed in automotive exhaust lines for the reduction of gasoline emissions. Two ceramic converters of different cell density, substrate length, hydraulic channel diameter and \vall thickness were studied to investigate the effect of varying key parameters on conversion efficiencies and pressure drop. Based on the emission test results, the conversion efficiencies of HC from both converters were calculated and evaluated

Experimental analysis to determine the relationship between noise and back pressure for muffler design – Part II: Experimental results

This chapter describes the final part of the detailed methodology of relationship between noise and back pressure for muffler design. This part includes experimental setup, experimental procedures, results and discussions. The experimental data show a general shape of an average design ofthe muffler which would be the most suitable for the test car

Exhaust system optimization using GT- Power

The exhaust system consists of the exhaust manifold, the header, the catalytic converter, the muffler, and the tailpipe. Certain flow characteristics must be met for the optimal performance of the exhaust system. The main objective of this chapter is to design exhaust system (particularly the exhaust manifold) using GT-Power software and to optimize its performance

Experimental analysis and simulation of catalytic converters

The purpose of this chapter is to present the results of an experimental study ofthe performance of ceramic monolith three-way catalytic converters (TWCC) employed in automotive exhaust lines for the reduction of gasoline emissions. Two ceramic converters of different cell density, substrate length, hydraulic channel diameter and wall thickness were investigated. After completing the test, the converters were cut to extract the substrate or 'honeycomb' inside the housing and being analyzed for microstructure and materials composition using Scanning Electron Microscopy (SEM) and Energy Dispersive Analysis (EDX). Simulation program using commercial computational fluid dynamics (CFD) software packages, GAMBIT and FLUENT 6.1 was used to verify experimental results

Experimental analysis to determine the relationship between noise and back pressure for muffler design – Part I: Muffler design requirements

This chapter describes part of the detailed methodology of relationship between noise and back pressure for muffler design. Starting with a brief introduction, an attempt is made here to present different steps of muffler design considering the relation between noise and back pressure. The design ofthe muffler chamber separation and arrangement is essential in determining the muffler characteristics. Some design considerations are proposed in order to come up with an optimum muffler design

Canalscape : a conceptual study to modify the existing landform in relation to the environment for the sustainable development of rural Bangladesh

This study reviews the existing physical, environmental, agricultural, and socioeconomical conditions of Bangladesh and problems associated with these. Poverty, exploding population, poor production in agricultural sectors with natural disturbance (such as excessive flooding and drought), and other environmental problems (such as deforestation and extinction of biota) hinder the progress of the nation. This study also investigates the possibility to reshape the existing landscape to reduce the ongoing crises by carrying out a new idea Canalscape. In this investigation, an attempt has been made to test the idea into an actual vilage. An economic analysis of this project has also been done to test its effectiveness. Findings 1. The rural poor makes up most of the population in Bangladesh, and their economy is predominantly dependent on agriculture. Thus, agriculture plays a major role in the nation\u27s developmental planning. 2. Flooding is a major problem of Bangladesh. Primary and secondary floods cause damage to the standing crops and inhibit the cultivation of modern high yielding varieties (HYV). Although tertiary flooding causes severe destruction, this is not a regular event in the monsoon cycle. As for agriculture, primary and secondary floods seem more important because of their occurrence during the critical period of crop growth. 3. If primary and secondary floods can be controlled, the country can achieve a significant increase in crop production. 4. The flat topography of the existing landscape makes this delta prone to flooding. If the landform can be modified so that it can hold the excessive water during flooding seasons, more crop area can be opened for cultivation. 5. Embanking the major rivers without making any attempts to circulate the floodwater into the flood plain will cause long term economic and environmental harm. 6. A Canalscape is simply a network of canals along with levees/roads to reshape the existing flat topography. This will control the movement of floodwater during monsoons and provide irrigation for dry winter seasons by storing the excess water in its system. This transformation, moreover, will intensify the total use of the land. The Canalscape suggests coping with the flood events rather than stopping them. 7. The Canalscape provides a necessary physical infrastructure to apply a successful farming system. To increase the overall production the Canalscape generates other income sources such as fishery, forestry, livestock, and so forth. 8. The Canalscape induces a relatively safer environmental condition and designs an organized social structure into it to sustain the growth. 9. If the transformation can be done properly, the land will become more productive. The example analysis in this study indicates that an approximate 200 percent increase in overall production could be possible

Quantum-Hall activation gaps in graphene

We have measured the quantum-Hall activation gaps in graphene at filling factors $\nu=2$ and $\nu=6$ for magnetic fields up to 32 T and temperatures from 4 K to 300 K. The $\nu =6$ gap can be described by thermal excitation to broadened Landau levels with a width of 400 K. In contrast, the gap measured at $\nu=2$ is strongly temperature and field dependent and approaches the expected value for sharp Landau levels for fields $B > 20$ T and temperatures $T > 100$ K. We explain this surprising behavior by a narrowing of the lowest Landau level.Comment: 4 pages, 4 figures, updated version after review, accepted for PR

3-Cylinder gasoline direct injection as opposed to 4-cylinder multi-port fuel injection for lower fuel consumption and NOX emission

The need for an engine that offers a low fuel consumption and good low-end torque grown for the past few years. The European environment protection agencies have drawn d<J the emission limits annually with emerging countries has started to adopt the European legislation. OEMs world wide have strived to meet the stringent regulation that made them develop smaller engine capacity with high low-end torque. Furthermore, continuously increas price of the fuel requires improving the engine efficiency. Electronic controlled Multi-Port Fuel Injection (MPFI) systems instead of fuel system with carburettor have been used since 1980 Development of small vehicle segments has started to look for alternatives to meet the consumption challenge. Therefore, adoption of gasoline direct injection (GOi) fuel systems new small engines hopefully can reduce hydrocarbon emissions by having fuelling and controls separated. Both 3-cylinder and 4-cylinder base engine configurations will be ex}: for the same engine capacity of 1.2 L. Improvements in hydrocarbon emissions, heat losses scavenging will be compared bet\veen the engmes. Plus, factors of packaging and considerations will also be look upon