• Journal of Institute of Convergence Technology
• /
• v.4 no.2
• /
• pp.67-70
• /
• 2014

Recently EU has been recognized that there is a difference of emission quantity between emission certification test mode and real-road driving test. Accordingly the European Commission is currently preparing to require real-road testing as part of the passenger car type-approval process in the EU. vehicle manufacturers from 2017 are expected to test new vehicles not only under laboratory conditions but also on the real-road, using PEMS equipment. Therefore the purpose of this study is to analyze the emission and Fuel Economy of CVS-75 mode test using chassis dynamometer and RDE test using PEMS equipment by PHEV passenger car.

• Journal of ILASS-Korea
• /
• v.21 no.4
• /
• pp.200-206
• /
• 2016

Recently, the certification procedure for exhaust emission regulation of LDV has tested with the NEDC mode in the laboratory. But the on-road exhaust emissions exceed the standard emission limits. Therefore, it is important to analyze the real-driving emissions (RDE) with a portable emissions measurement system (PEMS). In present study, the on-road emissions were measured with a PEMS and evaluated by moving averaging window (MAW) method. Also, it was compared with the $CO_2$ and $NO_x$ emissions for real-driving and test modes from euro-6 light-duty vehicles equipped with SCR and LNT systems. In results, on-road $NO_x$ emission has been 2.3-10.0 times higher than the standard $NO_x$ emission limit on NEDC mode. The reason was that the test modes did not reflect traffic and various real-driving patterns sufficiently.

• Journal of ILASS-Korea
• /
• v.21 no.4
• /
• pp.207-213
• /
• 2016

To protect air pollution of urban area from motor vehicles, emission limits for diesel vehicles have been dramatically lowered in short period. But recent studies have shown that on-road NOx emissions of light-duty diesel vehicles are considerably higher than the values measured with laboratory test procedures used for emission certification. To tackle with this issue, Ministry of Environment have a plan to introduce EU RDE-LDV (Real-driving Emission-Light-duty Vehicle) regulation. In this study, 4 Euro 6 diesel vehicles have been tested with the new test procedures published by EU to estimate on-road NOx emissions using PEMS (Portable Emission Measurement System). The results have shown that the requirements of EU RDE-LDV could be met in driving condition of metropolitan area for constitution of test routes and validity of test results. In analysing with Moving Averaging Window method the completeness and normality of test data were validated with the requirement. On-road NOx emissions were quite deviated as test vehicles and higher than the new limit of on-road NOx emission enforced from Sept. 2017, which means that RDE-LDV can effectively reduce NOx emission of diesel vehicles in real driving conditions of Korea.

• Journal of Drive and Control
• /
• v.20 no.3
• /
• pp.15-24
• /
• 2023

The aim of this study was to measure and evaluate the exhaust emission factors of agricultural tractors. Engine characteristics and three exhaust emissions (CO, NO_x, PM) were collected under actual agricultural operating conditions. Experiments were performed on idling, driving, plow tillage, and rotary tillage. The load factor (LF) was calculated using the collected engine data, and the emission factor was analyzed using the LF and exhaust emissions. The engine characteristics and exhaust emissions were significantly different for each working condition, and in particular, the LF was significantly different from the currently applied 0.48 LF. The data distribution of exhaust emissions was different depending on the engine speed. In some conditions, the emission factor was higher than the exhaust emission standards. However, since most emission limit standards are values calculated using an engine dynamometer, even if the emission factor measured under actual working conditions is higher, it cannot be regarded as wrong. It is expected that the results of this study can be used for the inventory construction of a calculation for domestic agricultural machinery emissions in the future.

• Journal of ILASS-Korea
• /
• v.23 no.4
• /
• pp.221-226
• /
• 2018

Despite the increasingly stringent automotive emissions regulations, the impact of vehicle emissions on air pollution remains large. In addition, since the issue of emission of more exhaust gas than the exhaust gas measured in the test room when the vehicle passing the exhaust gas regulation standard is run on the actual road, many countries studied and introduced gas regulations about Real Driving Emission using Portable Emission Measurement System. At present, Korea regulations restrict the number of NOx and PN in diesel vehicles. In the case of gasoline vehicles, there is no regulation on emission gas, but there is a problem of continuing automobile exhaust gas problems and a large amount of gasoline GDI vehicle's PN emission. So research and interest are increasing due to this problem. In this study, characteristics of exhaust gas depending on changes of ambient temperature were analyzed among various factors affecting exhaust gas measurement of gasoline vehicles. As a result, at the low temperature test, the lower the ambient temperature, the more the exhaust gas was emitted. At ordinary temperature test, no specific tendency was observed due to changes of ambient temperature.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.23 no.1
• /
• pp.130-138
• /
• 2015

Despite of recently strengthened vehicle emission regulations, NOx emissions are not decreased in urban areas because of discrepancies between certification emission test modes and real driving conditions. Thus, researches on RDE-LDV (Real-driving Emission-Light-duty Vehicle) have been conducted actively using PEMS (Portable Emissions Measurement Systems). In the present study, NOx emissions were measured for 5 Korean light duty vehicles for real driving conditions including city, combined, highway, and up-downhill test route. Emission characteristics were analyzed for averaged NOx emissions per unit driving distance of each driving test routes. Furthermore, MAW (Moving Average Window) method based on $CO_2$ emissions from WLTC, which will be supported for EU regulations, was utilized. It was revealed that DRs (deviation ratios) for diesel vehicles (i.e., 5.1 ~ 8.4) were greater than gasoline vehicles (less than 0.15). Especially DR of diesel vehicle for up-downhill test route was 8.4, which indicates severe NOx emissions.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.25 no.3
• /
• pp.287-296
• /
• 2017

Although emission regulations have been gradually strengthened in the past decade, the road transport section remains the most important source of NOx emission in air pollution. One reason is that there has been an increase in the proportion of diesel vehicles and in the volume of traffic. In addition, the certification procedure for standard emission limit does not sufficiently reflect real traffic condition and various driving patterns. Therefore, the European Commission(EC) has recently come up with the RDE-LDV(Real driving emissions-light duty vehicle) regulations, and the Ministry of Environment in Korea has been conducting research on evaluating RDE-LDV with PEMS(Portable Emission Measurement Systems). According to the trip requirements of the 2nd RDE package announced by the EC, the objectives of the present study include the development of Korean RDE routes to reflect domestic traffic and road conditions. Based on the results, both RDE routes are in correct compliance with RDE-LDV regulations, including trip requirements and trip dynamics. KOR-NIER Route 1, in particular, has a higher driving load in rural driving with regard to excessive gradient of elevation compared to KOR-NIER Route 2, including relatively plane rural driving.

• Korean Journal of Agricultural Science
• /
• v.50 no.3
• /
• pp.383-394
• /
• 2023

In Korea, the U.S. Tier-4 Final emission standards have been applied to agricultural machinery since 2015. This study was conducted to analyze the emission characteristics of agricultural tractors during plow tillage operations using PEMS (portable emissions measurement systems). The tractor working speed was set as M2 (5.95 km/h) and M3 (7.60 km/h), which was the most used gear stage during plow tillage operation. An engine idling test was conducted before the plow tillage operation was conducted because the level of emissions differed depending on the temperature of the engine (cold and hot states). The estimated level of emissions for the regular area (660 m²), which was the typical area of cultivation, was based on an implement width of 2.15 m and distance from the work area of 2.2 m. As a result, average emission of CO (carbon monoxide), THC (total hydrocarbons), NOx (nitric oxides), and PM (particulate matter) were approximately 6.17×10-2, 3.36×10^-4, 2.01×10^-4, and 6.85×10^-6 g/s, respectively. Based on the regular area, the total emission of CO, THC, NOx, and PM was 2.62, 3.76×10^-2, 1.63, and 2.59×10^-4 g, respectively. The results of total emission during plow tillage were compared to Tier 4 emission regulation limits. Tier 4 emission regulation limits means maximum value of the emission per consumption power (g/kWh), calculated as ratio of the emission and consumption power. Therefore, the total emission was converted to the emission per power using the rated power of the tractor. The emission per power was found to be satisfied below Tier 4 emission regulation limits for each emission gas. It is necessary to measure data by applying various test modes in the future and utilize them to calculate emission because the emission depends on various variables such as measurement environment and test mode.

• Journal of ILASS-Korea
• /
• v.23 no.3
• /
• pp.122-127
• /
• 2018

Recently, registrated passenger cars have increased and were close about seventy million at the end 2017 year in Korea. Among the passenger car using gasoline fuel make up forty six percentage of total registrated vehicles. In this study, investigation on real driving emission characteristics in the passenger car using gasoline fuel with various engine displacements were carried out. The real driving emission characteristics were measured and analyzed by using PEMS (Portable Emission Measurement System). PEMS was composed of gas analyzer, emission flow meter and sample conditioning system et al. Also, test six vehicles were selected to the gasoline passenger car with engine displacement from 1.6L to 3.7L. Two test routes with engine start of cold and hot conditions were applied to analyze the emission characteristics of RDE, respectively. The results show that the $CO_2$ emission have a increasing trend as the engine displacement and vehicle weight. Also, it is guessed that the $CO_2$ emission and vehicle weight were more correlated than the engine displacements. On the other hand, NOx emissions of RDE have not increasing or decreasing tendency according engine displacements or vehicle weight because the activation of three-way catalyst in the gasoline vehicles.

• Journal of ILASS-Korea
• /
• v.28 no.4
• /
• pp.184-190
• /
• 2023

The European Union has instituted a new emission standard protocol that necessitates real-time measurements from vehicles on actual roads. The adequate development of routes for real driving emissions (RDE) mandates substantial resources, encompassing both vehicles and a portable emission measurement system (PEMS). In this study, a simulation tool was utilized to predict the vehicle speed traversing the routes developed for the RDE measurements. Initially, the vehicle powertrain system was modeled for both a gasoline hybrid vehicle and a gasoline engine-only vehicle. Subsequently, the speed profile for the specified vehicle was constructed based on the RDE route developed for the EURO-6 standard. Finally, the predicted vehicle speed profiles for highway and urban routes were assessed utilizing the actual driving data. The driving model predicted more consistency in the vehicle speed at each driving section. Meanwhile, the human driver tended to accelerate further, and then decelerate in each section, instead of cruising at a predicted section speed.