Assessment of particle number limits for petrol vehicles

The European Commission Regulations No 692/2008 and No 715/2007 set the regulatory framework for type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5/6). However, these regulations leave open some issues regarding the Euro 6 emission standards to be addressed and defined before the entry into force of these pieces of legislation. Among them, the Type I test particle number limit for vehicles equipped with Positive Ignition Direct Injection engines should be defined. The Joint Research Centre has carried out a study to support a possible implementation of such a limit for Euro 6 petrol vehicles. The first part of this report provides a review of the particle mass and number emissions of gasoline Port Fuel Injection (PFI) and Gasoline Direct Injection (G-DI) vehicles available in the literature. Over the second part, the particle mass and number emissions from a range of Euro 4 and Euro 5 gasoline vehicle/engine technology measured at JRC are synopsized. The vehicles have been tested over various driving cycles and ambient temperature conditions according to the Particle Measurement Programme (PMP) methodology.JRC.F.8-Sustainable Transpor

Revision of Low Temperature Emission Standards for Petrol Vehicles

The Commission Regulations (EC) No 692/2008 and 715/2007 set the regulatory framework for type approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5/6. In particular these regulations set the emission standards and the related implementing measures, divided into three different steps, that will enter into force between 2009 (Euro 5) and 2014 (Euro 6). However the above mentioned Regulations leave open some issues regarding the Euro 5b and the Euro 6 emission standards to be addressed and defined before the entry into force of these pieces of legislation. As far as the low temperature emission test for gasoline vehicles is concerned the current emission limits, carried over from Euro 3/4, are no longer appropriate for vehicles meeting the Euro 5/6 emission standards. This report provides a picture of the low temperature emission performances (based on type approval data of Type VI test) of the current generation of gasoline vehicles. It also summarizes the main results of the experimental activity carried out at JRC to investigate the behaviour at low temperature of Euro 5 passenger cars and provide useful data for the revision of the low temperature emission standards for gasoline vehicles. Moreover, the analysis includes also results of Ethanol Flex Fuel Vehicles in view of the extension of the low temperature test to this category of vehicles.JRC.F.8-Sustainable Transpor

Extension of Low Temperature Emission Test to Euro 6 Diesel Vehicles

The European Commission Regulations No 692/2008 and No 715/2007 set the regulatory framework for type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5/6). One of the applicable tests is the low temperature emission test (Type VI), which is conducted at sub-ambient temperature conditions (-7°C). The low temperature emission test is currently required only for vehicles with positive ignition engines. However the Type VI test to diesel vehicles is under consideration, mainly because of the introduction of the new technologies in diesel engines in order to comply with the Euro5/6 emission standards, of which the efficiency in controlling emission may strongly depend on the ambient temperature. This is especially true for Exhaust Gas Recirculation (EGR) systems and after-treatment systems for Oxides of Nitrogen (NOx) that are deactivated or not operate in cold weather conditions, may result in elevated NOx emissions. The review should consider whether to extend the low temperature emission test to Euro 6 diesel vehicles and whether emission limit should be introduced in the future. This report provides a picture of the low temperature emission performances of late technology diesel vehicles The main results of the experimental activity carried out at JRC to investigate the behaviour at low temperature of Euro 5/6 diesel passenger cars are summarised and discussed.JRC.F.8-Sustainable Transpor

Evaluation of a Euro 4 vehicle with various blends of CNG/H2 fuel

The report presents the main results of an experimental campaign carried out by the JRC in the support of the legislative activities on type approval of hydrogen-powered motor vehicles. It serves as the scientific and technical basis to test the proposed methods for type approval regarding vehicles using a variable mixture of H2 and Compressed Natural Gas (CNG). A prototype bi-fuel vehicle is tested, designed to operate either on petrol or on various H2-CNG blends, with maximum percentage of 30% H2 on CNG. The methodology used to estimate the unburned hydrocarbon’s density, the fuel density, the fuel consumption, and the heating value of each H2-CNG blend in presented. The bag and modal gaseous emissions, as well as the particulate emission performances of the vehicle tested under the various H2-CNG blends and on petrol fuel is presented. It can be concluded that the use of such fuel mixtures can provide a positive input to the reduction of pollutant emissions as well as of greenhouse gas emissions.JRC.F.8-Sustainable Transpor

Particle Emissions from a Euro 5a Certified Diesel Passenger Car

The particle emissions of a Euro 5 technology DPF-equipped diesel passenger car were characterized under regulated and unregulated conditions. More specifically, the vehicle was tested under the New European Driving Cycle but also under the Common Artemis Driving Cycles. Measurements were conducted at 22°C and -7°C test cell temperatures. The particle characteristics investigated included PM mass emissions as well as “non-volatile” particle number emissions. The PMP compliant particle number measurement system was supplemented with two additional CPCs allowing for the quantification of unregulated sub-23 nm particles in the size bins of 4.5 to 10 nm and 10 nm to 23 nm. The DPF regenerated actively thrice during the measurement campaign providing some information on the emission performance of the vehicle under these conditions.JRC.DDG.F.9-Sustainable Transport (Ispra

Lack of an association between SCFD1 rs10139154 polymorphism and amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease. Through a genome‑wide association study (GWAS), the Sec1 family domain‑containing protein 1 (SCFD1) rs10139154 variant at 14q12 has emerged as a risk factor gene for ALS. Moreover, it has been reported to influence the age at onset (AAO) of patients with ALS. The aim of the present study was to assess the association of the SCFD1 rs10139154 polymorphism with the risk of developing ALS. For this purpose, 155 patients with sporadic ALS and 155 healthy controls were genotyped for the SCFD1 rs10139154. The effect of the SCFD1 rs10139154 polymorphism was then examined on the following parameters: i) The risk of developing ALS; ii) the AAO of ALS; iii) the site of ALS onset (patients with bulbar onset ALS vs. healthy controls; and patients with limb onset ALS vs. healthy controls); and iv) the AAO of ALS onset with subgroup analyses based on the site of onset (bulbar and limb, crude and adjusted for sex). The analysis of all the outcomes was performed assuming five genetic models. Crude and adjusted analyses were applied. The threshold for statistical significance was set at 0.05. The results revealed no association between SCFD1 rs10139154 and any of the examined phenotypes in any of the models examined. On the whole, based on the findings of the present study, SCFD1 rs10139154 does not appear to play a determining role in the risk of developing ALS

Solid sub-23nm particle number emission measurement inter-laboratory comparison exercise

An interlaboratory comparison exercise of solid, sub-23nm particle number emission (PN) measurements was conducted in 10 emission laboratories. The exercise was divided in two parts: European part (EU) consisting of seven different laboratories and Asian part comprising three different laboratories. In the exercise a light-duty gasoline direct injection vehicles and two reference solid particle number measurement systems and additional particle number counter for >10 nm particle counting were circulated in the laboratories. Solid particle number concentrations were measured from the full dilution tunnel in parallel with reference systems including both >23 nm and >10 nm particle number counters (PN23, PN10) and the laboratory solid particle number measurement system (PMP) also including both >23 nm and >10 nm particle number counters. The reference systems were equipped with catalytic evaporation tubes while the laboratory systems had evaporation tubes. The determined average PN10 and PN23 emissions were the same for all the instruments within the inter-laboratory coefficient of variance (s_L), separately for different test cycles in the first exercise parts (EU). In the second part, the low number of laboratories affected the results, yet, the PN10 and PN23 results for different instruments were within 20%. In general, reproducibility coefficient of variance (S_R) were at the same level for PN10 and PN23, thus suggesting that PN10 measurement is feasible with the reference methods.JRC.C.4 - Sustainable, Smart and Safe Mobilit

Transport and reaction phenomena in catalyzed diesel particulate filters

The main target of this thesis is the study of coupled transfer and reaction phenomena that take place in Catalyzed Diesel Particulate Filters. The study is based on measurements and simulation tools of the transient behavior of particulate filters and oxidation catalysts, which have been developed by Laboratory of Applied Thermodynamics. The examination of catalyzed filters begins with their filtration efficiency and pressure drop behavior during the loading conditions. The new semi-empirical mathematical model of filtration efficiency simulation is presented for first time, and validated against various operating conditions. The presence of washcoat loading increases the filtration efficiency and the pressure drop, due to the decrease of the filter’s porosity. At high flow rate conditions and large mean pore size substrate the amount of soot collected in the wall is larger, affecting the passive regeneration behavior of the filter. The Catalyzed Diesel Particulate Filter (CDPF) and the Diesel Oxidation Catalyst (DOC) were examined on their gaseous oxidation performance of diesel exhaust. At steady - state and high flow rate operating conditions the CDPF is more effective at the HC oxidation performance. At transient conditions the DOC is more effective to the gaseous oxidation performance. The study which follows examines the low-temperature passive regeneration behavior of catalyzed filters. At 330°C the systems with DOC upstream are more effective during regeneration, due to the increased NO2 concentration, which acts directly on the soot layer. At 400°C the regeneration is based on the NO2 diffusion phenomena. The study of high temperature - active regeneration performance follows. If the filter soot loading is controlled at levels below a carefully selected threshold , e.g. in the range of 8 g/l, via the regeneration control system, then the single CDPF system and the DOC+CDPF one exhibit comparable efficiencies and maximum temperatures, during the active regeneration with post injection. The study is completed with the evaluation of a zoned catalyzed filter, with axial zones of different activity. A catalyzed filter with larger precious metal loading at its front part is examined experimentally and computationally. The CDPF with the larger amount of Pt at its front part can replace the uniform coated one, with a great advantage at the cost.Βασικός στόχος της εργασίας είναι η μελέτη των φαινομένων μεταφοράς μάζας και ενέργειας, καθώς και των χημικών αντιδράσεων σε κεραμικά φίλτρα σωματιδίων με καταλυτική επίστρωση. Η μελέτη βασίζεται τόσο σε πειράματα, όσο και σε χρήση υπολογιστικών εργαλείων προσομοίωσης της μεταβατικής λειτουργίας του φίλτρου αιθάλης και του οξειδωτικού καταλυτικού μετατροπέα, που έχουν εξελιχθεί από το Εργαστήριο Εφαρμοσμένης Θερμοδυναμικης. Η εξέταση των καταλυτικών φίλτρων ξεκινά με τη μελέτη της συμπεριφοράς τους όσον αφορά στην απόδοση διήθησης και στην πτώση πίεσης κατά τη διάρκεια της φόρτισής τους με αιθάλη. Το νέο ημι-εμπειρικό μοντέλο υπολογισμού της απόδοσης διήθησης που παρουσιάζεται για πρώτη φορά, επαληθεύεται σε ποικίλες συνθήκες λειτουργίας. Η παρουσία της καταλυτικής επικάλυψης αυξάνει την απόδοση διήθησης και την πτώση πίεσης, λόγω της μείωσης του πορώδους του τοιχώματος του φίλτρου. Σε συνθήκες υψηλής παροχής και σε υπόστρωμα με μεγάλο μέσο μέγεθος πόρων, η αιθάλη που συσσωρεύεται στο τοίχωμα είναι περισσότερη, επηρεάζοντας στη συνέχεια τη συμπεριφορά του φίλτρου κατά την αναγέννηση Διερευνήθηκε η οξειδωτική δραστηριότητα συστημάτων απλού καταλυτικού φίλτρου (CDPF) και συστήματος οξειδωτικού καταλύτη και καταλυτικού φίλτρου (DOC+CDPF). Υπό σταθερές συνθήκες λειτουργίας και υψηλής παροχής, το CDPF είναι αποδοτικότερο στην οξείδωση των HC. Υπό μεταβατικές συνθήκες θέρμανσης ο DOC είναι αποδοτικότερος στην οξείδωση των CO και ΗC. Η εξέταση των συστημάτων αντιρρύπανσης συνεχίστηκε με τη μελέτη της παθητικής αναγέννησης υπό χαμηλή θερμοκρασία. Στους 330°C τα συστήματα με DOC αποδεικνύονται αποτελεσματικότερα στην αναγέννηση, λόγω της αυξημένης συγκέντρωσης του εισερχόμενου ΝΟ2 στο CDPF. Στους 400°C ενισχύεται ο μηχανισμός αναγέννησης με το ΝΟ2 που παράγεται στο καταλυτικό τοίχωμα και διαχέεται στην σωματιδιακή στρώση. Ακολούθησε η εξέταση της συμπεριφοράς των καταλυτικών φίλτρων σε συνθήκες εξαναγκασμένης αναγέννησης, υπό υψηλή θερμοκρασία καυσαερίου. Αν η φόρτιση της αιθάλης ελέγχεται στα 8g/l μέσω του συστήματος ελέγχου της αναγέννησης, τότε είναι δυνατή η αφαίρεση του DOC από το σύστημα DOC+CDPF χωρίς μεγάλη διαφορά στην εξέλιξη της ενεργητικής αναγέννησης με δευτερογενή έγχυση καυσίμου. Προσομοιώθηκε για πρώτη φορά καταλυτικό φίλτρο με δύο ζώνες καταλυτικής επίστρωσης διαφορετικής δραστικότητας. To CDPF με αξονικά μη ομοιόμορφη κατανομή φόρτισης Pt με περισσότερη ποσότητα μπροστά μπορεί να αντικαταστήσει το ομοιόμορφα επικαλυμμένο CDPF, με όφελος στο κόστος

Low-temperature cold-start gaseous emissions of late technology passenger cars

The control of exhaust emissions from modern vehicles is based on the use of after-treatment devices typically consisting in different types of catalysts. The efficiency of catalytic systems however strictly depends on their temperature, achieving certain effectiveness in reducing emissions only above the light-off temperature. This generally leads to elevated emissions during cold-start operation, especially under low ambient temperatures. We investigated the gaseous emission performance of thirteen latest technology vehicles over the New European Driving Cycle (NEDC), at 22°C and -7°C test cell temperatures. The test fleet included gasoline vehicles both Port Fuel Injection (PFI) and Gasoline Direct Injection (G-DI) as well as diesel vehicles, amongst which a fully Euro 6 compliant vehicle equipped with a Selective Catalytic Reduction (SCR) system. The test results showed that Carbon Monoxide (CO) and total Hydrocarbons (HC) emissions of gasoline vehicles increased from 2.3 to 11.3 times at -7°C over the Urban Driving Cycle (UDC), remaining however below the current legislative limits by 45% and 65% respectively. Nitrogen Oxides (NOx) emissions of gasoline vehicles at -7° turned out to be either higher or lower than at 22°C, depending on the catalyst’s performance and engine injection strategy. Diesel vehicles without any NOx after-treatment system exhibited increased NOx emissions over both the UDC and Extra Urban Driving Cycle (EUDC) when tested at -7°C. The diesel car with the SCR system showed superior NOx performance only over the second half of the NEDC.JRC.F.8-Sustainable Transpor