EU-PEMS PM Evaluation Program - First Report

The European legislation has adopted the Portable Emissions Measurement Systems (PEMS) as a tool to check the conformity of heavy-duty engines during their real operation. The current developments foresee the verification of gaseous emissions. The measurement and the control of in-service Particulate Mass (PM) emissions using on-board equipment has been delayed, as the technological status of the portable PM instrumentation had been judged insufficient. The European PEMS PM project was launched in 2007. Its main objective was to assess the technological status of the PEMS PM equipment. Initially, the main requirements set for the candidate instruments were: - to measure the PM mass, possibly according to existing standards; - to be designed for on-board testing regarding handling, test durations and power consumption; - to be advanced prototypes or commercially available equipment. An additional but important requirement was introduced: to be able to evaluate the in-service emissions (which is done in the United States through the Not To Exceed (NTE) approach), the European legislation has adopted a moving averaging window method. For such calculations, the accumulated PM mass had to be measured or estimated at any time during a test. The strategy used to evaluate the candidate instruments was simple and empirical. Using different engines, test cycles and fuels, the candidates were required to provide the best possible correlation with the reference laboratory systems. This ¿laboratory to portable¿ comparison was carried out for to the total PM mass measurements. The real-time PM results have been cross-correlated. In parallel to the program, some Particle Number (PN) measurements have been performed using equipment and test procedures in line with the European standards developed to test light-duty vehicles. This abstract provides the main findings of this project regarding PM, as presented and discussed in the final report of the European PEMS PM program. Furthermore, it gives the engine PN emissions and provides a first clue regarding the feasibility of PN for in-service testing. Different PM PEMS were evaluated in the lab with 3 heavy-duty engines which cover a wide range of emissions. The PM differences were in general 15% lower (SPC, OBS, micro-PSS) than the PM measured with a full dilution tunnel. Higher differences (35%) were found for MSS which measures soot. For the DPF engine the differences were >50% due to the volatile artifact on the filter. The PN differences between CVS and SPC were for all engines (and emission levels) within 15%. In addition to the PN method (non-volatiles measured with a CPC), MSS and DC were found to be sensitive enough at the low emission levels (post DPF). ETaPS and DMM (with dilution) were not sensitive enough for DPF engine. The conclusion of this work is that mass (on a filter) is not sensitive enough for low emission engines and the number method should be preferred. If PEMSs continue to use the filter method, then the real time instrument they use can affect the calculation factor as each instrument measures different particle property (number, surface, mass). Nevertheless, all these parameters do not affect the result enough to exceed the 10 mg/kWh limit of the future European HD regulation. They should be however seriously taken into account for lower emission levels.JRC.DDG.H.4-Transport and air qualit

Particle Measurement Programme (PMP) Heavy-Duty (HD) Inter-laboratory Exercise: Exploratory Work at JRC (Oct2007 - Feb2008)

This document reports the results of the exploratory work during the PMP Heavy-Duty inter-laboratory exercise - from Oct. '07 to Feb. '08 - conducted at the Vehicles Emissions Laboratory (VELA-5) in the Transport and Air Quality Unit of the European Commission¿s Joint Research Centre (JRC, Ispra). This report presents the results of the work undertaken on an IVECO Cursor 8 Heavy-Duty engine equipped with a Continuous Regenerating Trap (CRT), i.e. the Golden Engine. Main objective of these tests were to finalize the measurement protocol that will be used in the validation exercise and the round robin. These tests included background tests, filter media effect, filter face velocity, preconditioning effect, comparisons of different particle number systems, and investigation of the golden instruments.JRC.H.4-Transport and air qualit

EU-PEMS PM Pilot Program: Testing, data analysis and results.

The present work was conducted in the frame of the EU PEMS PM Evaluation programme. The program was launched in 2008 by the European Commission [1] to assess the potential of portable instruments to measure particulate emissions on-board of vehicles. The EU-PEMS program is a voluntary program, receiving contributions from the European Joint Research Centre (JRC), some portable emissions instrument manufacturers (AVL, Control Sistem, Sensors Inc, Horiba) and the European association of heavy-duty engines manufacturers (ACEA). After the successful completion of the laboratory evaluation program with the identification and recommendation of the candidate principles [3, 4, 5], the second phase of the process was launched with the on-road measurement of PM with the updated instrumentation recommended in the validation program (PEMS PM Pilot Program). The PEMS PM Pilot program concludes the research phase of the PEMS PM instrumentation into its inclusion in the Euro VI regulationJRC.F.8-Sustainable Transpor

Hyperspectral and LiDAR data for the prediction via machine learning of tree species, volume and biomass: a possible contribution for updating forest management plans

This work intends to lay the foundations for identifying the prevailing forest types and the delineation of forest units within private forest inventories in the Autonomous Province of Trento (PAT), using currently available remote sensing solutions. In particular, data from LiDAR and hyperspectral surveys of 2014 made available by PAT were acquired and processed. Such studies are very important in the context of forest management scenarios. The method includes defining tree species ground-truth by outlining single tree crowns with polygons and labeling them. Successively two supervised machine learning classifiers, K-Nearest Neighborhood and Support Vector Machine (SVM) were used. The results show that, by setting specific hyperparameters, the SVM methodology gave the best results in classification of tree species. Biomass was estimated using canopy parameters and the Jucker equation for the above ground biomass (AGB) and that of Scrinzi for the tariff volume. Predicted values were compared with 11 field plots of fixed radius where volume and biomass were field-estimated in 2017. Results show significant coefficients of correlation: 0.94 for stem volume and 0.90 for total aboveground tree biomass

In Service Monitoring based on PEMS of NRE engines under 19kW

This report summarizes the results of a pilot program dedicated to develop a procedure for the In Service Monitoring of NRMM Small Compressed Ignition engines (categories NRE-v-1, NRE-v-2, NRE-c-1, NRE-c-2) based on Portable Emission Measurement System (PEMS). The tests took place between January 2018 and February 2019. The work addresses how to mount the measurement equipment on board of such machinery and the accuracy and precision of the exhaust gaseous pollutant emission measurements using PEMS. Compared to a standard test performed in an engine test cell (VELA_6 and at OEM facilities) the concentration measurements accuracy and precision was within 10%. In service tests showed that the results were stable and reproducible.JRC.C.4-Sustainable Transpor

EU-PEMS PM Evaluation Program - Second Report - Study on Post DPF PM/PN Emissions

This study evaluated the performance of five in total candidate PEMS-PM systems at diesel exhaust PM levels spanning from 20 mg/kWh (Euro V) to post CRT. The different emission levels were simulated by means of a CRT/bypass configuration. The PEMS-PM systems evaluated included Horiba's On Board System with Transient PM measurement (OBS-TRPM), AVL's Micro Soot Sensor (MSS) and Gravimetric Filter Box (GFB), Control Sistem's micro Particulate Sampling System (m-PSS), Sensors Portable Particulate Measurement Device (PPMD) and Dekati's Mass Monitor (DMM). The correlation between the PM results determined with the PEMS instrumentation and that measured with the laboratory sampling systems was found to depend on the filter media employed. This was attributed to adsorption artefacts that become more important as the PM levels decrease. Teflo filters were found to be less susceptible to gas adsorption artefacts, but were difficult to handle yielding some times even negative masses. Even with Teflo filters, however, more than 99% of the PM at CRT out levels was OC which could not be detected by the real time aerosol instrumentation and therefore is expected to be adsorbed material. Furthermore, background PM levels at all candidate systems utilizing laboratory conditioned dilution air averaged at a level equivalent to 3 mg/kWh which is almost 1/3 of the Euro VI level. The background was even higher (equivalent to ~5 mg/kWh) for the PEMS system that employed ambient air (internally conditioned) for the dilution. The study also evaluated the performance of the real time sensors employed in the different candidate systems using both engine exhaust aerosol and Poly(Alpha)-Olephin spherical particles. The results of these experiments revealed a number of issues related to the calibration of the instruments and cross sensitivities to non PM sources. These findings need to be addressed by the manufacturers as they are expected to significantly affect the accuracy of the measurements in PEMS applications.JRC.DDG.F.9-Sustainable Transport (Ispra

Particle Measurement Programme (PMP) Heavy-Duty (HD) Inter-laboratory Exercise - Validation Exercise Tests at JRC (Phase A: Feb. '08 and Phase B: June '08)

This document reports the results of the validation exercise during the PMP Heavy-Duty inter-laboratory exercise in Feb. ¿08 (Phase A) and June ¿08 (Phase B) conducted at the Vehicles Emissions Laboratory (VELA-5) in the Transport and Air Quality Unit of the European Commission¿s Joint Research Centre (JRC, Ispra). This report presents the results of the work undertaken on an IVECO Cursor 8 Heavy-Duty engine equipped with a Continuous Regenerating Trap (CRT), i.e. the Golden Engine. The tests included European and World Harmonized cycles following a strict protocol. Mass and number measurements were conducted simultaneously at the full flow and the partial flow sampling systems.JRC.H.4-Transport and air qualit

EU-PEMS PM Evaluation Program - Third Report – Further Study on Post DPF PM/PN Emissions

This study evaluated the performance of five in total candidate PEMS-PM systems at diesel exhaust PM levels spanning from 20 mg/kWh (Euro V) to post DPF. The different emission levels were simulated by means of a DPF/bypass configuration. The PEMS-PM systems evaluated included Horiba’s On Board System with Transient PM measurement (OBS-TRPM), AVL’s Micro Soot Sensor (MSS) and Gravimetric Filter Box (GFB), Control Sistem’s micro Particulate Sampling System (m-PSS), Sensors Portable Particulate Measurement Device (PPMD) and Dekati’s Mass Monitor (DMM). The work focused on the effect of sampling time on the performance of the PEMS-PM instrumentation. To this end, repeated WHTC tests were performed with PM samples taken over a single WHTC but also over three consecutive test cycles. Teflon filters exhibited superior performance from TX40 and Quartz filters, showing little dependence on the sampling time and at the same time resulting in better agreement between the reference instrumentation and the candidate PEMS-PM systems. The study also evaluated the performance of the real time sensors following some revisions and modifications considered by the manufacturers in response to the findings of the previous (phase 2) campaign. The experimental results verified the improved performance of the revised instrumentation but also revealed some areas for further improvements.JRC.DDG.F.9-Sustainable Transport (Ispra