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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.

A series of chassis dynamometer test trials were conducted to assess the performance of a Fourier Transform Infra Red (FTIR) system developed for on-road vehicle exhaust emissions measurements. Trials used a EURO 1 emission compliant SI passenger car which, alongside the FTIR, was instrumented to allow the routine logging of engine speed, road speed, throttle position, air-fuel ratio, air flow and fuel flow in addition to engine, exhaust and catalyst temperatures. The chassis dynamometer facility incorporated an ‘industry standard’ measurement system comprising MEXA7400 gas analyzer and CVS bag sampling which was the ‘benchmark’ for the evaluation of FTIR legislated gas-phase emissions (CO, NOx, THC and CO2) measurements. Initial steady state measurements demonstrated strong correlations for CO, NOx and THC (R2 of 0.99, 0.97 0.99, respectively) and a good correlation for CO2 (R2 = 0.92).

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.

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.

An in-vehicle FTIR emission measurement system was used to investigate the exhaust emissions under different real world urban driving conditions. Five different driving cycles were developed based on real world urban driving conditions including urban free flow driving, junction maneuver, congested traffic and moderate speed cruising. The test vehicle was a EURO 2 emission compliant SI car equipped with temperature measurement along the exhaust pipe across the catalyst and real time fuel consumption measurement system. Both regulated and non-regulated emissions were measured and analyzed for different driving cycles. All journeys were started from cold. The engine warm up features and emissions as a function of engine warm up for different driving conditions were investigated.

An investigation was conducted into particulate PAH emissions from a heavy duty DI diesel engine using; a typical diesel fuel, 100% methyl ester derived from waste cooking oils, and 100% rapeseed oil supplied as fresh cooking oil. This study quantifies the particulate PAH levels emitted at two steady state load conditions, with comparison of the oxidation catalyst efficiency for the main species identified. The engine used was a 6 cylinder, turbocharged, intercooled Perkins Phaser engine, with emission compliance of EURO 2. Particulate samples were also analysed for VOF and carbon content. Both biofuels resulted in reductions in the most abundant particulate PAH species, particularly at the lower load condition. Larger species such as Benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo (k)fluoranthene were detectable for all fuels upstream of the catalyst but were oxidized to near or below detection limits downstream of the catalyst.

Regulated and non-regulated tailpipe 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. A EURO3 emission compliant SI car was used as a probe vehicle. An 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 TWC needed approximately 200 seconds to reach full conversion efficiency. THC and NOx emissions exceeded the EURO 3 exhaust emission legislation. CO2 emissions were well above the type approval value of this type of the vehicle. Greenhouse gases (methane and nitrous oxide) and toxic hydrocarbons such as benzene were predominantly emitted during cold start period from 0 to 200 seconds of the engine start. The results had a reasonable repeatability for most of the emissions.

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.

The transport sector is one of the major contributors to greenhouse gas emissions. This study investigated three greenhouse gases emitted from road transport: CO2, N2O and CH4 emissions as a function of engine warm up and driving cycles. Five different urban driving cycles were developed and used including free flow driving and congested driving. An in-vehicle FTIR (Fourier Transform Inferred) emission measurement system was installed on a EURO2 emission compliant SI (Spark Ignition) car for emissions measurement at a rate of 0.5 HZ under real world urban driving conditions. This emission measurement system was calibrated on a standard CVS (Constant Volume Sampling) measurement system and showed excellent agreement on CO2 measurement with CVS results. The N2O and CH4 measurement was calibrated using calibration gas in lab. A MAX710 real time in-vehicle fuel consumption measurement system was installed in the test vehicle and real time fuel consumption was then obtained.