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A FTIR in-vehicle on-road emission measurement system was installed in a EURO2 emissions compliant SI (Spark Ignition) car to investigate exhaust Volatile Organic Compounds (VOC) emissions and Ozone Formation Potential (OFP) under different urban traffic conditions. The real time fuel consumption and vehicle traveling speed were 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 (West Park Loop cycle) was located in a quiet area with few traffic interference and the other one (Hyde Park Loop 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 influence of contamination of lubricating oil on the emissions of total particulate, particulate polycyclic aromatic hydrocarbons (PAH) and unburnt fuel and gaseous emissions have been investigated for a modified Perkins 4.236 D.I. diesel engine. The emissions during fuel firing and motoring in the absence of fuel are compared. The results showed that the exhaust particulate during both firing and motoring were not affected by lubricating oil contamination. Emission of PAH during fuel firing and motoring increase with oil contamination which in turn reflects the build up of PAH with oil age. Some of the particulate PAH are biologically active. The contribution of oil derived PAH increase with age. Comparison of the gaseous emissions during fuel firing and during motoring also showed an increase in UHC with age of lubricating oil.

The role of lubricating oil in total particulate emmissions and in terms of polycyclic aromatic compounds (PAC) associated with the solvent organic fraction (SOF) of the particulate are investigated. Analysis of unused lubricating oil shows negligible concentrations of PAC. Used lubricating oil from a modified Perkins 4.236 Diesel engine, showed significant concentrations of PAC had accumulated in the oil in the form of PAC from unburnt fuel. Analysis of the oil was by gas chromatography using simultaneous parallel triple detection, allowing analysis of polycyclic aromatic hydrocarbons (PAH), nitrogen containing PAH (PANH) and sulphur containing PAH (PASH). Motoring the engine in the absence of fuel enabled the contribution of lubricating oil to the exhaust particulate and particulate PAC emission to be determined.

A method of cleaning lubricating oil on line was investigated using a fine bypass particulate filter followed by an infrared heater, to remove water and light diesel fractions in the oil. The impact of this oil recycler with 1 micron fine bypass filter on oil quality was investigated over a 72 hour oil age. Comparisons tests were undertaken without and with the recycler on a Euro 2 Perkins Phaser 180Ti 6 cylinder 6 litre turbo-charged inter-cooled DI diesel engine. The tests were carried out at 2000rpm and 100kW with 473 Nm load. A stop start test cycle was used with a cold start each time and a typical test period of 2 hours. The results showed that the oil quality in this low emission engine test was extremely good. The on line recycler achieved improvements in the oil quality. With the recycler, the carbon accumulation rate in the oil was reduced by 78%. The carbon removal rate by the recycler was 0.40 g/hr. The wear metals in the oil were significantly reduced.

A method of cleaning lubricating oil on line was investigated using a one micron bypass particulate filter followed by an infra-red heater, to remove water, dissolved gases and light diesel fractions in the oil. The impact of this oil recycler on oil quality was studied using synthetic oil in an on-road bus test. The bus was of Euro-1 emissions standard and equipped with a Cummins 6 cylinder 8.3 litre turbo-charged inter-cooled DI engine. Comparisons tests were undertaken with and without the oil recycler for about 28,000 miles. Oil samples were analysed about every 2000 miles. The results showed that the on line oil recycler achieved significant improvements in the oil quality. With the recycler, the TBN depletion rate was reduced by 52%, the TAN increase rate was reduced by 27% and the carbon accumulation rate in the oil was reduced by 42%. The fuel dilution was reduced by the recycler.

A method of cleaning lubricating oil on line was investigated using a fine 1μm bypass particulate filter followed by a 150°C infra-red heater, to remove water and light diesel fractions in the oil. The impact of this oil recycler on diesel particulate and gaseous emissions was investigated over a 72 hour oil age. Comparison tests were undertaken without and with the recycler on a Euro 2 Perkins Phaser 180Ti, 6-cylinder, 6-litre, turbo-charged inter-cooled DI diesel engine fitted with an oxidation catalyst. Emissions were sampled from both upstream and downstream of the catalyst about every 10 hours. The tests were carried out at 2000rpm and 100kW with 473 Nm load. A stop start test cycle was used with a cold start each time and a typical test period of 2 hours. The results showed that this engine had extremely low particulate emissions and was well inside the Euro 2 emissions limits.

A method of cleaning diesel engine lubricating oil on-line was investigated using a bypass fine particulate filter followed by an infra-red heater to remove water vapour and light diesel fractions in the oil. The impact of this oil recycler on the gaseous and particulate emissions was investigated over a 300 hour oil age period. A Ford 1.8 litre IDI passenger car diesel engine was used with engine out emission sampled every 15-20 hours. The tests were carried out at 2500rpm (52% of the maximum speed) and 12.3 kW with 47 Nm load (43% of the maximum load and 29% of the maximum power). The EGR level at this condition was 15%. A stop start test cycle was used with a cold start each time and a typical test period of 2-3 hours. The results showed that the recycler had its greatest influence on emissions for fresh oil when there was a large reduction in particulate emissions due mainly to large reductions in the ash, carbon and unburned lubricating oil fractions.

A method of cleaning lubricating oil on line was investigated using a fine bypass particulate filter followed by an infra red heater, to remove water and light diesel fractions in the oil. 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. These vehicles had oil deterioration and emissions characteristics that were significantly different, in spite of their similar age and total mileage. Comparison was made with the oil quality on the same vehicles and engines with and without the on-line recycler. Oil samples were analysed about every 2000 miles. All tests started 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 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.

Two Ford IDI passenger car diesel engines, 1.6 and 1.8 litres, were tested over a 100 hour lube oil ageing period with engine out emission samples every 15 hours. The 1.6 litre engine was tested with 5% EGR and the 1.8 litre engine with 15% EGR. Comparison was also made with previous work using an older Petter AA1 engine. The three engines had different dependencies of particulate emissions on the lube oil age. The 1.6 litre engine increased the particulates from 1 to 2.5 g/kg of fuel, whereas the 1.8 litre engine first decreased the particulate emissions from 3 to 1 g/kg over 50 hours of oil age and then they increased to 2 g/kg at 100 hours. This was similar to the previous work on the Petter AA1 engine, where the emissions first decreased and then increased as the oil aged. For the 1.8 litre engine the lube oil fraction of the VOF was high with fresh oil and decreased with time for the first 50 hours and then remained steady.

This work investigates the heating of unprocessed rapeseed oil as a means to improve fuel delivery by reducing the fuel viscosity, and to assess the effects on combustion performance. The results show that a simple low power heater with thermal insulation around the fuel line and pump can effectively raise the operational fuel temperature at delivery to the pump. The results show that even with a moderate temperature increase, the fuel flow limitations with rapeseed oil are reduced and the legislated gaseous emissions are reduced at steady state conditions. As one of the main reasons for the conversion of straight oils to the methyl ester, ie biodiesel, is to reduce the viscosity, this work shows that heating the oil can have a similar effect. An emissions benefit is observed with biodiesel compared to rapeseed oil but this is not large. There is also a significant greenhouse gas and cost benefit associated with straight vegetable oils.

The objective was to investigate PAH emissions in diesel particulates using two diesel fuels with different PAH content. Class A2 diesel from two different refinery sources were analysed for PAH and there were significant difference in the concentration of the 3 and 4 ring PAH of importance in particulate PAH emissions. One fuel had at least 20 times the benzo[a]pyrene (BaP) of the other. A mass balance between the fuel PAH input to the engine and the particulate PAH emissions was carried out. A similar mass balance was also carried out between the equivalent boiling point n-alkane fuel and particulate SOF, which determined how that distillation fraction of the fuel behaved in the engine. One of the fuels had a higher survivability of high MW n-alkanes and this was also reflected in the PAH emissions. The fuel with high BaP had BaP emissions entirely consistent with an unburned fuel source.

The influence of ambient temperature on exhaust emissions for an instrumented Euro 1 SI car was determined. A real world test cycle was used, based on an urban drive cycle that was similar to the ECE urban drive cycle. It was based on four laps of a street circuit and an emissions sample bag was taken for each lap. The bag for the first lap was for the cold start emissions. An in-vehicle direct exhaust dual bag sampling technique was used to simultaneously collect exhaust samples upstream and downstream of the three-way catalyst (TWC). The cold start tests were conducted over a year, with ambient temperatures ranging from - 2°C to 32°C. The exhaust system was instrumented with thermocouples so that the catalyst light off temperature could be determined. The results showed that CO emissions for the cold start were reduced by a factor of 8 downstream of catalyst when ambient temperature rose from -2°C to 32°C, the corresponding hydrocarbon emissions were reduced by a factor of 4.

The contribution of spark ignition engine particulate emissions to total particulate emissions and the published data on SI engine emission levels are reviewed. There is a wide spread of published data and the worst SI engines would exceed the future diesel particulate emissions regulations. However, most modern SI engines with a catalyst will easily meet the future diesel particulate emissions regulations, although their particulates emissions are a significant fraction of these regulations. Steady state lambda 1 results are presented for a Ford Zetec SI engine at conditions representative of the urban driving cycle at 5 and 10kW power output and also at WOT. The impact of a cold start and EGR at the two low power conditions was also investigated. The particulate emissions for petrol were of the order of 5% of the future (2005) diesel emissions regulations and were approximately 20 mg/kg fuel (about 2 mg/mile or 1.3 mg/km).

The role of lubricating oil as a sink for polycyclic aromatic compounds (PAC) and alkanes derived from unburnt fuel is described for two different oils used in two different DI diesel engines. The diesel engines used were, an older technology Petter AV1 single cylinder mine pumping engine and a Perkins 4.236 current technology engine. Analysis of the oil was by gas chromatography using simultaneous parallel triple detection, allowing analysis of hydrocarbons and nitrogen and sulphur containing compounds. Analysis of unused lubricating oil showed negligible concentrations of PAC and low molecular weight alkanes (< C20). The oil from each engine was analysed periodically during use and showed a rapid and significant accumulation of hydrocarbons which reached significant concentrations after only 10 hours use. The older technology engine showed a much higher accumulation rate.

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.

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.

A 10W-50 G4 synthetic lubricating oil (EULUBE oil) was tested on a heavy duty DI diesel engine under two steady state conditions. The exhaust emissions were measured and compared to a 10W-30 CF semi-synthetic lubricating oil. The EULUBE oil contained the friction reduction additive to improve the fuel economy. 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. Gaseous and particulates emissions were measured. Particulate size distribution was measured using ELPI and SMPS. The particulate samples were 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. The results showed a significant reduction by synthetic lubricating oil in gaseous hydrocarbon emissions, total particulate mass, particulate carbon and ash.

A method of cleaning lubricating oil on line was investigated using a fine 1 micron bypass particulate filter, followed by an infra-red heater to remove water and light diesel fractions in the oil. A Ford 1.8 litre IDI diesel passenger car was investigated under real world driving conditions. Comparison was made with the oil quality without the recycler. All the tests were carried out on the same vehicle over 7000 miles with and without the recycler. The results showed that the on line oil recycler cleaning system reduced the rate of reduction of TBN and the rate of increase of TAN by 54% and 50% respectively. The reduction in the rate of carbon accumulation in the oil was 42%. There was also a reduction in fuel dilution. All the wear metals in the oil were greatly reduced by the recycler, the iron was reduced by 76%, the lead was reduced by 85% and the aluminum was totally removed.

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.