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Exhaust emissions were measured under real world urban driving conditions using a set of in-vehicle FTIR emission measurement system, which is able to measure 65 emission components simultaneously at a rate of 0.5 Hz. The test vehicle was a modern EURO4 emission compliant SI car equipped with temperature measurement along the exhaust pipe across the catalyst so as to match thermal characteristics to emission profiles. A free flow urban driving cycle was used for the test and four repeated journeys were conducted. The results were compared to EU emissions legislation. The results show that the warm up of the lubricating oil needed 15 minutes. The TWC needed about 200 seconds to reach full conversion efficiency. CO, THC and NOx emissions exceeded the EURO4 exhaust emission legislation. CO2 emissions were well above the type approval value of this vehicle.

Rape oil, as used in fresh cooking oil (FCO), and the methyl ester derived from waste cooking oil (WCOB100) were tested as 100% biofuels (B100) on a heavy duty DI diesel engine under steady state conditions. The exhaust emissions were measured and compared to those for conventional low sulphur (<50ppm) diesel fuel. The engine used was a 6 cylinder, turbocharged, intercooled Perkins Euro2 Phaser Engine, fitted with an oxidation catalyst. The engine out gaseous emissions results for WCOB100 showed a large decrease in CO and HC emissions, but a small increase in NOx emissions compared to diesel. However, for FCO the CO and HC increased relative to WCOB100 and CO was higher than for diesel, indicating deterioration in fuel/air mixing. The particulate matter (PM) emissions for WCOB100 were similar to those for diesel at the 23kw condition, but greatly reduced at 47kw. The FCO produced higher engine out PM at both power conditions due to a higher volatile organic fraction (VOF).

EURO 1, 2 3 and 4 SI (Spark Ignition) Ford Mondeo passenger cars were compared for their real world cold start emissions using an on-board FTIR (Fourier Transform Infrared) exhaust emission measurement system. The FTIR system can measure up to 65 species including both regulated and non-regulated exhaust pollutants at a rate of 0.5 Hz. The driving parameters such as speed, fuel consumption and air/fuel ratio were logged. The coolant water, lube oil and exhaust temperatures were also recorded. A typical urban driving cycle including a loop and a section of straight road was used for the comparison test as it was similar to the legislative ECE15 urban driving cycle. Exhaust emissions were calculated for the whole journey average and compared to EU legislation. The cold start transient emissions were also investigated as a separate parameter and this was where there was the greatest difference between the four vehicles.

A FTIR in-vehicle on-road emission measurement system was installed in a EURO 2 emissions compliant SI car to investigate exhaust emissions under different urban traffic conditions. The real time fuel consumption and vehicle traveling speed was measured and logged. The temperatures were measured along the exhaust pipe so as to monitor the thermal characteristics and efficiency of the catalyst. Two real world driving cycles were developed with different traffic conditions. One (WP cycle) was located in a quiet area with few traffic interference and the other one (HPL cycle) was in a busy area with more traffic variations. The test car was pre-warmed before each test to eliminate cold start effect. The driving parameters were analyzed for two real world cycles. The WP cycle had higher acceleration rate, longer acceleration mode and shorter steady speed driving mode and thus harsher than the HPL cycle.

Lubricating oil takes all of the NEDC test cycle time to reach 90°C. Hence, this gives high friction losses throughout the test cycle, which leads to a significant increase in the fuel consumption. In real world driving, particularly in congested traffic, it is shown that lube oil warm-up is even slower than in the NEDC. Euro 1, 2 and 4 Ford Mondeo water and oil warm up rates in real world urban driving were determined and shown to be comparable with the results of Kunze et al. (2) for a BMW on the NEDC. This paper explores the use of forced convective heat exchange between the cooling water and the lube oil during the warm-up period. A technique of a step warm-up of the engine at 32 Nm at 2000 rpm (35% of peak power) was used and the engine lube oil and water temperature monitored. It was shown that the heat exchanger results in an increase in lube oil temperature by 4°C, which increased to 10°C if enhanced heat transfer to the water was used from an exhaust port heat exchanger.

Exhaust emissions were measured under real world urban driving conditions using a set of in-vehicle FTIR emission measurement system, which is able to measure 65 emission components simultaneously at a rate of 0.5 Hz. The test vehicle was a EURO 2 emission compliant SI car equipped with real time fuel consumption measurement and temperature measurement along the exhaust pipe across the catalyst allowing the matching of thermal characteristics to emission profiles and monitor fuel consumption. The temperature profile indicated that the light-off of the catalyst took about 150∼200 seconds. The warm up of the lubricating oil and coolant water required a longer time than the catalyst did. The impact of ambient temperatures on lubricating oil and coolant water warm ups was greater than that on the light-off of the catalyst. The heat loss and energy balance were calculated during the whole cycle period. The influence of cold start on fuel consumption was investigated.

With growing concern over greenhouse gases there is increasing emphasis on reducing CO2 emissions. Despite engine efficiency improvements plus increased dieselisation of the fleet, increasing vehicle numbers results in increasing CO2 emissions. To reverse this trend the fuel source must be changed to renewable fuels which are CO2 neutral. A common route towards this goal is to substitute diesel fuel with esterified seed oils, collectively known as Fatty Acid Methyl Esters. However a fundamental change to the fuel chemistry produces new challenges in ensuring compatibility between fuel and engine performance/durability. This paper discusses the global situation and shows how fuel additives can overcome the challenges presented by the use of biodiesel.

A precision in-vehicle tail-pipe emission measurement system was installed in a EURO1 emissions compliant SI car and used to investigate the variability in tail-pipe emission generation at an urban traffic junction and uphill/downhill road, and thereby the impact of road topography on emissions. Exhaust gas and skin temperatures were also measured along the exhaust pipe of the instrumented vehicle, so the thermal characteristics and the efficiency of the catalyst could be monitored. Different turning movements (driving events) at the priority T-junction were investigated such as straight, left and right turns with and without stops. The test car was run until hot stable operating conditions were achieved before each test, thereby negating cold start effects.

A rapeseed methyl ester biodiesel RMEB100 was tested on a heavy duty DI diesel engine under steady state conditions. The combustion performance and exhaust emissions were measured and compared to a standard petroleum derived diesel fuel. The engine used was a 6 cylinder, turbocharged, intercooled Perkins Phaser Engine, with emission compliance of EURO 2, fitted with an oxidation catalyst. The exhaust samples were taken both upstream and downstream of the catalyst. Particulates were collected and analysed for VOF, carbon and ash. A MEXA7100 gas analysis system was used for legislated gas analysis such as CO, CO2, NOx and total hydrocarbons. A FTIR analysis system was deployed for gaseous hydrocarbon speciation, which is capable of speciating up to 65 species. The results showed a significant reduction in total particulate mass, particulate VOF, CO, THC and aldehydes when using RMEB100.

Condensable and gaseous hydrocarbon emissions and speciation of the hydrocarbons have been investigated using a EURO1 emissions compliant SI (Spark Ignition) car. Exhaust gas samples were simultaneously collected upstream and downstream of the catalyst using a system containing cold ice trap, resin, particulate filter block and Teflon gas sampling bag. GC (Gas Chromatography) was employed to analyze for hydrocarbons and 16 of the more significant hydrocarbons are reported. The test was carried out using both cold start and hot start driving cycles. Results show that the benzene and toluene were major species emitted from the tailpipe under cold start conditions. Methylnaphthalene was a dominated hydrocarbon under hot start conditions. The cold start had significant influence on hydrocarbon emissions. The catalyst out benzene emissions for cold start was thirty times higher than that for hot start.

A precision in-vehicle tail-pipe emission measurement system was installed in a EURO1 emissions compliant SI car and used to investigate the variability in tail-pipe emission generation at an urban traffic junction. Exhaust gas and skin temperatures were also measured along the exhaust pipe of the instrumented vehicle, so the thermal characteristics and the efficiency of the catalyst monitored could be included in the analysis. Different turning movements (driving patterns) at the priority T-junction were investigated such as straight, left and right turns with and without stops. The test car was hot stable running conditions before each test, thereby negating cold start effects. To demonstrate the influence of the junction on tail-pipe emissions and fuel consumption, distance based factors were determined that compared the intersection drive-through measurements with steady speed (state) runs. Fuel consumption was increased at intersections by a factor of 1.3∼5.9.

Thermal characteristics of SI engine exhaust during cold start and warm up period were investigated for different ambient temperatures (-2 to 32 °C). A Euro 1 emission compliance SI car was tested using a real world urban driving cycle to represent typical city driving patterns and simulate ECE15 urban driving cycle. The test car was equipped with 27 thermocouples along the engine and exhaust pipes so as to measure metal and exhaust gas temperatures along the engine, exhaust and catalyst. The characteristics of thermal properties of engine, exhaust system and catalyst were studied as a function of warm up time and ambient temperature. The temperature and time of the light-off of catalyst were investigated so as to evaluate the effect of thermal properties of the catalyst on emissions. The results show that the coolant water reached the full warm up about 5 minutes in summer and 9 minutes in winter after a cold start.

Mass weighted size distributions of particulate emissions as a function of oil age were investigated using a set of Anderson Impactors on an IDI passenger car engine test. This engine was fitted with an on-line bypass lubricating oil recycler aiming to extend the oil life, reduce fuel consumption and exhaust emissions. A stop start test cycle was used with a cold start each time and a typical cycle period of 2∼3 hours. The whole test was carried out for nearly 500 hours. The first 310 hours of testing were with the oil recycler fitted and thereafter the test continued with the oil recycler disconnected. The results show that 60∼80% of mass particulates were smaller than 1.1 μm in aerodynamic diameter with the oil recycler fitted and this percentage was reduced to 40∼60% after disconnection of the oil recycler. The changes in size distribution with oil age mainly happened in the size ranges of 1.1∼0.65 μm, 0.65∼0.43 μm and <0.43 μm.

Impending legislation will make it almost inevitable that heavy-duty trucks will have to be fitted with some form of particulate removal after-treatment device. The challenge is to provide a system that is not only environmentally acceptable and cost effective but also durable enough to meet the demands of the trucking industry. Diesel particulate filters (DPF), in conjunction with fuel borne catalysts to facilitate regeneration, are now a recognised technology for meeting future passenger car emissions limits. Retrofitting of such systems to older technology vehicles, where specific environmental concerns exist, has demonstrated the possibility of applying this technology to the heavy-duty vehicle sector. Most of these retrofit applications tend to be to vehicles with a relatively low duty cycle. Whereas this type of duty cycle poses the greatest challenge to the successful regeneration of the filters it is not necessarily the most arduous test of the durability of the system.

There is mounting worldwide concern over the health effects of airborne ultra-fine particles. Of greatest concern are the risks due to the cancer-inducing properties of these particles and the aggravation of existing respiratory diseases by the ultra-fine (i.e. <2.5 micron) fraction. This disquiet has already resulted in legislation, regulations and other measures, either mandated or proposed, in the industrialised world to severely restrict particulate emissions from diesel-fuelled automotive transport. Emissions of particles from both new and existing vehicles have been addressed. With the rapid growth anticipated in some developing countries they to will need to address this problem. This paper outlines some alternative solutions to the problem, ranging from alternative power sources, alternative fuels, alternative engine technologies and after-treatment strategies. It also outlines what is required to implement these different solutions.

A method of cleaning lubricating oil on line was investigated using a fine bypass particulate filter followed by an infra red heater. Two bypass filter sizes of 6 and 1 micron were investigated, both filter sizes were effective but the one micron filter had the greatest benefit. This was tested on two nominally identical EURO 2 emissions compliance single decker buses, fitted with Cummins 6 cylinder 8.3 litre turbocharged intercooled engines and coded as Bus 4063 and 4070. These vehicles had emissions characteristics that were significantly different, in spite of their similar age and total mileage. Bus 4063 showed an apparent deterioration on emissions with time while Bus 4070 showed a stabilised trend on emissions with time for their baseline tests without the recycler fitted. Comparison was made with the emissions on the same vehicles and engines with and without the on-line bypass oil recycler. Engine exhaust emissions were measured about every 2000 miles.

A method of cleaning lubricating oil on line was investigated using a fine bypass particulate filter followed by an infra red heater. Two bypass filter sizes of 6 and 1 micron were investigated, both filter sizes were effective but the one micron filter had the greatest benefit. This was tested on two nominally identical EURO 1 emissions compliance refuse trucks, fitted with Perkins Phazer 210Ti 6 litre turbocharged intercooled engines and coded as RT320 and RT321. These vehicles had emissions characteristics that were significantly different, in spite of their similar age and total mileage. RT321 showed an apparent heavier black smoke than RT320. Comparison was made with the emissions on the same vehicles and engines with and without the on-line bypass oil recycler. Engine exhaust emissions were measured about every 400 miles. Both vehicles started the test with an oil drain and fresh lubricating oil.

A method of cleaning lubricating oil on line was investigated using a fine bypass particulate filter followed by an infra red heater. Two bypass filter sizes of 6 and 1 micron were investigated, both filter sizes were effective but the one micron filter had the greatest benefit. This was tested on two nominally identical EURO 1 emissions compliance refuse trucks, fitted with Perkins Phazer 210Ti 6 litre turbocharged intercooled engines and coded as RT320 and RT321. These vehicles had lubricating oil deterioration and emissions characteristics that were significantly different, in spite of their similar age and total mileage. RT321 showed an apparent heavier black smoke than RT320. Comparison was made with the oil quality and fuel and lubricating oil consumption on the same vehicles and engines with and without the on-line bypass oil recycler. Engine oils were sampled and analysed about every 400 miles. Both vehicles started the test with an oil drain and fresh lubricating oil.

Diesel particulate filter (DPF) technology is becoming increasingly established as a practical method for control of particulate emissions from diesel engines. In the year 2000, production vehicles with DPF systems, using metallic fuel additive to assist regeneration, became available in Europe. These early examples of first generation DPF technology are forerunners of more advanced systems likely to be needed by many light-duty vehicles to meet Euro IV emissions legislation scheduled for 2005. Aspects requiring attention in second generation DPF systems are a compromise between regeneration kinetics and ash accumulation. The DPF regeneration event is activated by fuel injection, either late in the combustion cycle (late injection), or after normal combustion (post injection), leading to increased fuel consumption. Therefore for optimum fuel economy, the duration of regeneration and/or the soot ignition temperature must be minimised.

Trapping diesel particulates is effective in reducing both the number and the mass of fine particulate emissions from diesel engines, but unless the accumulated soot can be burned out or regenerated periodically, the vehicle to which the trap is fitted will cease to function after a relatively short time. A programme of work with soot traps using a low treat rate iron-strontium organo-metallic fuel additive to assist and secure regeneration has been carried out. As part of this programme, an advanced specification diesel engine passenger car equipped with a diesel particulate filter (DPF), was operated on roads in the UK for approximately 18 months, during which time the vehicle covered over 50,000 km After completion of 50,000 km on roads, the vehicle was operated on a chassis dynamometer to increase the distance covered with a DPF more rapidly to a final total of 80,000 km.