A study in the reduction of efficiency of nitrogen oxide removal catalysts for automobiles

Automotive catalysts are the most effective short-term answer to air pollution from automobiles. Since strict control of exhaust emissions is, or will be,covered by legislation in most developed countries in the world, catalytic devices will be increasingly fitted to cars. There is consequently an urgent need for the development of catalysts that will not compete for scarce precious metal resources. A number of problems have already been identified in connection with base metal catalysts but quantitative investigations are lacking. The base metal reduction catalysts developed by Imperial Chemical Industries Limited, catalysts and Chemical Group, in collaboration with the Air Pollution Control Laboratory, B L Cars Limited for automotive emission control, are susceptible to de-activation by three major mechanisms. These are: physical loss of the wash-coat (a high surface area coating which supports the active species), aggregation of the active species and poisoning by fuel and engine oil additives. This thesis is especially concerned with the first two of these and attempts to indicate the relative magnitude .of their effect on the activity of. the catalysts. Aggregation of the active species or sintering, as it is loosely called, was studied by using impregnated granules to overcome effects due to the loss of the wash-coat. Samples were aged in a synthetic exhaust gas, free from poisons, and metal crystallite sizes were measured by scanning-electron microscopy. The increase in particle size was correlated with the loss in catalytic activity. In order to maintain a link with the real conditions of service a number of monolithic catalysts were tested in an engine-dynamometer and several previously tested endurance catalysts were examined. A mechanism is proposed for the break-up and subsequent 10s.5 of the wash-coat and suggestions for improved resistance to loss of the' coating and active species are proposed.

In-Motes EYE:a real time application for automobiles in wireless sensor networks

Wireless sensor networks have been identified as one of the key technologies for the 21st century. In order to overcome their limitations such as fault tolerance and conservation of energy, we propose a middleware solution, In-Motes. In-Motes stands as a fault tolerant platform for deploying and monitoring applications in real time offers a number of possibilities for the end user giving him in parallel the freedom to experiment with various parameters, in an effort the deployed applications to run in an energy efficient manner inside the network. The proposed scheme is evaluated through the In-Motes EYE application, aiming to test its merits under real time conditions. In-Motes EYE application which is an agent based real time In-Motes application developed for sensing acceleration variations in an environment. The application was tested in a prototype area, road alike, for a period of four months.

The contribution of modularity to green operations practices

This paper discusses the possible contributions from modularity and industrial condominiums towards enhancing environmental performance in the automotive industry. The research described in this study is underpinned by a review of journal articles and books on the topics of: modularity of production systems; green operations practices, and the automotive industry and sustainability. The methodology is based on theoretical analysis of the contribution of the modular production system characteristics used in the automotive industry for Green Operations Practices (GOP). The following GOPs were considered: green buildings, eco-design, green supply chains, greener manufacturing, and reverse logistics. The results are theoretical in nature; however, due to the small number of studies that investigate the relationship between modularity and sustainability, this work is relevant to increase knowledge in academic circles and among practitioners in order to understand the possible environmental benefits from modular production systems. For instance, based upon our analysis, we could deduce that the existing modular production systems in the automotive industry may contribute in different ways to the implementation of GOPs. In all types of modularity, product simplification through the use of modules can enhance environmental performance and facilitate further activities such as maintenance and repair contributing to a longer life of cars on the road. Moreover, modules will make automobiles easier to disassembly, so increasing the chances of reuse of valuable components and a better final disposal of scrap. Regarding the potential benefits of each type of modularity, it is expected that modular consortia will have a better integration of environmental practices with suppliers and seize on high efficiency during manufacturing and logistics compared with conventional production systems.

Quality risk in global supply network

Purpose - The rise of recent product recalls reveals that manufacturing firms are particularly vulnerable to product quality and safety where goods and materials have been sourced globally. The purpose of this paper is to explore the issues of quality and safety problems in global supply networks, and introduce a supply chain risk management (SCRM) framework to reduce the quality risk. Design/methodology/approach - A conceptual SCRM framework for mitigating quality risk is developed. In addition, four SCRM treatment practices are proposed by consolidating the empirical literature in the operations management and supply chain management areas. The general feasibility was discussed based on literature. Findings - The research has identified the root causes of the recent product recalls and a series of product harm scandals ranging from automobiles to unsafe toys. Supply chains are extended by outsourcing and stretched by globalization, which greatly increase the complexity of supply networks and decrease the visibility in risk and operation processes. Originality/value - The paper identifies four SCRM practices, and proposes two distinct antecedents that can prompt the effectiveness of SCRM. © 2011 Emerald Group Publishing Limited. All rights reserved.

The acceptability of alcohol fuels for automobile engines

The aim of this project was to carry out an investigastion into suitable alternatives to gasoline for use in modern automobiles. The fuel would provide the western world with a means of extending the natural gasoline resources and the third world a way of cutting down their dependence on the oil producing countries for their energy supply. Alcohols, namely methanol and ethanol, provide this solution. They can be used as gasoline extenders or as fuels on their own.In order to fulfil the aims of the project a literature study was carried out to investigate methods and costs of producing these fuels. An experimental programme was then set up in which the performance of the alcohols was studied on a conventional engine. The engine used for this purpose was the Fiat 127 930cc four cylinder engine. This engine was used because of its popularity in the European countries. The Weber fixed jet carburettor, since it was designed to be used with gasoline, was adapted so that the alcohol fuels and the blends could be used in the most efficient way. This was mainly to take account of the lower heat content of the alcohols. The adaptation of the carburettor was in the form of enlarging the main metering jet. Allowances for the alcohol's lower specfic gravity were made during fuel metering.Owing to the low front end volatility of methanol and ethanol, it was expected that `start up' problems would occur. An experimental programme was set up to determine the temperature range for a minimum required percentage `take off' that would ease start-up since it was determined that a `take off' of about 5% v/v liquid in the vapour phase would be sufficient for starting. Additions such as iso-pentane and n-pentane were used to improve the front end volatility. This proved to be successful.The lower heat content of the alcohol fuels also meant that a greater charge of fuel would be required. This was seen to pose further problems with fuel distribution from the carburettor to the individual cylinders on a multicylinder engine. Since it was not possible to modify the existing manifold on the Fiat 127 engine, experimental tests on manifold geometry were carried out using the Ricardo E6 single cylinder variable compression engine. Results from these tests showed that the length, shape and cross-sectional area of the manifold play an important part in the distribution of the fuel entering the cylinder, ie. vapour phase, vapour/small liquid droplet/liquid film phase, vapour/large liquid droplet/liquid film phase etc.The solvent properties of the alcohols and their greater electrical conductivity suggested that the materials used on the engine would be prone to chemical attack. In order to determine the type and rate of chemical attack, an experimental programme was set up whereby carburettor and other components were immersed in the alcohols and in blends of alcohol with gasoline. The test fuels were aerated and in some instances kept at temperatures ranging from 50oC to 90oC. Results from these tests suggest that not all materials used in the conventional engine are equally suitable for use with alcohols and alcohol/gasoline blends. Aluminium for instance was severely attacked by methanol causing pitting and pin-holing in the surface.In general this whole experimental programme gave valuable information on the acceptability of substitute fuels. While the long term effects of alcohol use merit further study, it is clear that methanol and ethanol will be increasingly used in place of gasoline.