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The sustainability of biodiesel adoption in diesel engines are dependent on its environmental friendliness relative to lower pollutant emissions. Biodiesel was produced from extracted Parinari polyandra oil via alkali catalyzed methanolysis. Performance and emission analysis of a diesel engine was conducted on a diesel engine, operated under different operating conditions, using varied Parinari polyandra biodiesel blends. Exhaust emissions, like total hydrocarbons, carbon dioxide, carbon monoxide, sulphur dioxide, and nitrogen oxides were measured. The biodiesel properties were found to be similar to fossil diesel. B10 was found to be the optimal blend in improving the engine performance in terms of speed, power and thermal efficiency. B30 demonstrated stable performance characteristics without any modification of the diesel engine. The exhaust emissions from biodiesel blends combustion were found to be lower than that of diesel, except nitrogen oxides. High percentage reduction of greenhouse gases, carbon monoxide and carbon dioxide, was recorded at 81.7% and 65.7%, respectively. The utilization of Parinari polyandra biodiesel for engine application was found to be a viable means of heightening adoption of sustainable biofuels and minimizing pollutant emissions from the combustion of fossil fuels.

Exhaust gas temperature is one of the main parameters under engine manufacturers' focus due to its effects on both turbocharger durability and catalyst efficiency. Typically, the measurement of such variable at the test bench is carried out by using thermocouples (TCs), which are not available for on-board applications. For this reason, an accurate and reliable model for Real-Time (RT) calculation of this variable is particularly important. In this work a control-oriented model for the estimation of exhaust temperature in Spark Ignition (SI) engines is developed and validated exploiting experimental data. A fundamental quantity that has to be necessarily known is the temperature of the gas within the exhaust manifold or at the Exhaust Valve Opening (EVO). The first part of this paper deals with the development of a zero-dimensional (0-D) combustion model, identifying the main parameters of the Wiebe function with an automatic optimization routine. Such method allows to accurately reproduce the in-cylinder pressure trace and calculate the temperature of the gas at EVO. Hence, an analytical function that converts such temperatures into the exhaust manifold ones is developed by analyzing the experimental measurements of TCs installed in the exhaust manifold under steady-state operating conditions. This is the main reason why the proposed approach cannot be considered fully empirical. The resulting 0-D model is not suitable for an RT application nor to be implemented in an Engine Control Unit (ECU) due to a differential equation that needs to be solved in the angular domain. For this reason, in the second part of the article, a control-oriented model is developed by using an analytical methodology, which exploits the combustion model and the temperature analytical function presented in the first part. Finally, the control-oriented model is coupled with a TC dynamics RT model, and both are validated under transient conditions.

An original improvement of modern information models of conventional engine is proposed. Within the model all internal as well as external processes related to engine are integrated to a general system. Additional procedure to simulate nitric oxide kinetics in a combustion chamber is elaborated. The problem of exhaust toxicity is solved in relation to partial engine loads. Compared to prototypes the model enables to estimate engine toxicity appreciably more precise.

Some original modifications of the genetic algorithms for analyzing the stationary states of the chemical dynamic systems at the defined thermodynamic parameters, IC engines among others, are offered. The development feature is allocation of small and large equation parameters among the equations and their solutions. Along with the known neuronet methods, the development can be integrated in ‘Engine’ simulation system.

Atmospheric aerosol particle number concentrations impact our climate and health in ways different from those of aerosol mass concentrations. However, the global, current and future anthropogenic particle number emissions and their size distributions are so far poorly known. In this article, we present the implementation of particle number emission factors and the related size distributions in the GAINS (Greenhouse Gas–Air Pollution Interactions and Synergies) model. This implementation allows for global estimates of particle number emissions under different future scenarios, consistent with emissions of other pollutants and greenhouse gases. In addition to determining the general particulate number emissions, we also describe a method to estimate the number size distributions of the emitted black carbon particles. The first results show that the sources dominating the particle number emissions are different to those dominating the mass emissions. The major global number source is road traffic, followed by residential combustion of biofuels and coal (especially in China, India and Africa), coke production (Russia and China), and industrial combustion and processes. The size distributions of emitted particles differ across the world, depending on the main sources: in regions dominated by traffic and industry, the number size distribution of emissions peaks in diameters range from 20 to 50 nm, whereas in regions with intensive biofuel combustion and/or agricultural waste burning, the emissions of particles with diameters around 100 nm are dominant. In the baseline (current legislation) scenario, the particle number emissions in Europe, Northern and Southern Americas, Australia, and China decrease until 2030, whereas especially for India, a strong increase is estimated. The results of this study provide input for modelling of the future changes in aerosol–cloud interactions as well as particle number related adverse health effects, e.g. in response to tightening emission regulations. However, there are significant uncertainties in these current emission estimates and the key actions for decreasing the uncertainties are pointed out.

The parts in this report that are classified have been replaced by the symbol □.Even axes in some figures have been erased by the same reason.In emission legislation from California Air Resources Board, CARB, futuredemands on misfire detection in heavy duty diesel vehicles will cover anextended operating area than previous demands. Industry standard has so farbeen using crank shaft speed based methods. It is not obvious that speedbased methods will manage to detect misfire in the extended area.This report shows an alternative approach for misfire detection, based uponmeasured pressure in the exhaust manifold. The method compares themeasured pressure pattern with known templates. This work shows that themethod works at stationary measurements in the whole required operatingarea. Furthermore, measurements has shown that the exhaust brake can beused at pressures up to about □□□ hPa without any significant change to theexhaust pressure pattern. The influence of waste gate use at low load has beenanalysed. It shows low influence on the pressure trace when using misfiredetection template. Finally location of the pressure sensor has been studied,showing a possibility to improve misfire detection by placing the sensor closeto the exhaust port at the cylinder where improvement is needed. De delar av denna rapport som är hemligstämplade har ersatts av symbolen□. Även axlar i vissa figurer har raderats av samma skäl.I emissionslagstiftning från California Air Resources Board, CARB, kommermisständningsdetektion för tunga dieselfordon att krävas i ett störrearbetsområde än vad som tidigare kravställts. Industristandard har hittillsvarit varvtalsbaserad misständningsdiagnos, men det är inte uppenbart attden metoden kommer att klara detektion i det utökade lagkravsområdet.Denna rapport visar en alternativ metod för misständningsdetektion sombaseras på uppmätt tryck i avgassamlaren. Metoden som används jämföruppmätt avgastryck mot ett känt mönster. Det har i detta arbete visats attmetoden fungerar vid stationära mätningar i hela lagkravsområdet. Vidare harmätningar visat att avgasbroms kan användas upp till ca □□□ hPa mottryckutan att tryckmönstret ändras signifikant. Inverkan av turbons waste gate vidlåga laster har analyserats och visar låg påverkan i fall då man användermisständning som detektionsmönster. Slutligen har placering avtrycksensorer analyserats. Denna visar att det går att förbättradetektionsförmågan genom att placera sensorn närmare utblåset på dencylinder man önskar förbättra detektionen.

In this study, effects of the canola biodiesel blends in 5%, 10%, 15% and 20% proportions (in vol.) with diesel fuel were investigated at four loads (4.8, 3.6, 2.4 and 1.2 bar BMEP) in a single-cylinder DI engine. Comprehensive combustion analyses showed that, although the start of injection timings were inadvertently advanced from the system response, the combustion of canola biodiesel blends generally resulted in shorter ignition delay period for all loads due to earlier combustion timing. The maximum heat release rate generally decreased gradually with the reduction of premixed combustion fractions and corresponding increase in the diffusion combustion fractions when the canola biodiesel ratio was increased. Slightly reducing the maximum in-cylinder pressures and maximum in-cylinder pressure rise rates were caused a slight retardation on the center of heat release locations and longer combustion durations. BSFC results increased up to 6.56% and BTE reduced up to 4.2% when the canola biodiesel ratio was increased to 20% at the high load. The canola biodiesel blends also resulted in higher NOx emissions of 8.9% as well as lower smoke, CO and THC but slightly higher CO2 emissions for all loads. (C) 2017 Elsevier Ltd. All rights reserved.

[EN] Exhaust temperature is a valuable parameter for engine control. However, measurement conditions at the engine exhaust and the slow dynamic response of temperature sensors difficult the determination of the instantaneous exhaust temperature. The present paper proposes a methodology for estimating the exhaust temperature exclusively relying in-cylinder pressure signal, engine speed and exhaust lambda.The presented methodology can replace or actualize widespread look-up table models for correcting calibration offsets, due to ageing, sensor bias or disturbances associated with the engine operation. The method uses the existence of resonant modes in the in-cylinder pressure for inferring the trapped mass and the in-cylinder temperature. An isentropic expansion of the gasses through the valves is assumed for estimating the cylinder outlet temperature of the gases, and the gas temperature drop along the exhaust runner and manifold is modelled through a nodal thermal model. The method was compared with current models under steady and transient conditions in a four stroke CI engine. Variations of injection, EGR, intake pressure and rail pressure were performed under steady operation and the transient response of the method was validated under specific transient test and at the WLTP cycle. A time invariant first order model was used for comparing the estimated temperature with that provided by the experimental sensors. (C) 2016 Elsevier Ltd. All rights reserved., This research has been partially financed by the Spanish Ministerio de Economia Competitividad, through project TRA2013-40853-R "Desarrollo de nuevas tecnicas de limitation de la perdida de presion en DPFs para reducir las emisiones y el consumo de los motores diesel (PRELIMIT)".

This work is aimed at the basic analysis of diesel oil and rapeseed methyl ester and evaluation of limited and unlimited emission produced by their combustion. Thereafter, test results are compared, and there is also done the evaluation of emission – greenhouse gases, dangerous exhaust gases and strong carcinogens and their contents during fuel combustion. These measurements were performed at the Research Station Agroscope ART in Tanikon (AAT) in Switzerland and in cooperation with the Department of Transport and Handling (DTH), Faculty of Engineering, Slovak University of Agriculture in Nitra.

This study explores a large set of OC and EC measurements in PM10 and PM2.5 aerosol samples, undertaken with a long term constant analytical methodology, to evaluate the capability of the OC/EC minimum ratio to represent the ratio between the OC and EC aerosol components resulting from fossil fuel combustion (OCff/ECff). The data set covers a wide geographical area in Europe, but with a particular focus upon Portugal, Spain and the United Kingdom, and includes a great variety of sites: urban (background, kerbside and tunnel), industrial, rural and remote. The highest minimum ratios were found in samples from remote and rural sites. Urban background sites have shown spatially and temporally consistent minimum ratios, of around 1.0 for PM10 and 0.7 for PM2.5.The consistency of results has suggested that the method could be used as a tool to derive the ratio between OC and EC from fossil fuel combustion and consequently to differentiate OC from primary and secondary sources. To explore this capability, OC and EC measurements were performed in a busy roadway tunnel in central Lisbon. The OC/EC ratio, which reflected the composition of vehicle combustion emissions, was in the range of 0.3–0.4. Ratios of OC/EC in roadside increment air (roadside minus urban background) in Birmingham, UK also lie within the range 0.3–0.4. Additional measurements were performed under heavy traffic conditions at two double kerbside sites located in the centre of Lisbon and Madrid. The OC/EC minimum ratios observed at both sites were found to be between those of the tunnel and those of urban background air, suggesting that minimum values commonly obtained for this parameter in open urban atmospheres over-predict the direct emissions of OCff from road transport. Possible reasons for this discrepancy are explored. This research work was partially supported by the Portuguese Science Foundation (FCT) under projects POCI/AMB/60627/2004 (Chemical characterization of PM2.5 and PM10 urban aerosol) and PTDC/AMB/65699/2006 (Polycyclic Aromatic Hydrocarbons contamination in Lisbonurban atmosphere). César Oliveira and Fátima Mirante acknowledge FCT for their scholarships. published

Biomass fuel combustion for residential energy significantly influences both emissions and the atmospheric burden of aerosols in world regions, i.e., east and south Asia. This study reports measurements of climate-relevant properties of particles emitted from biomass fuels widely used for cooking in south Asia, in laboratory experiments simulating actual cooking in the region. Fuel burn rates of 1-2 kg h(-1) for wood species, and 1.5-2 kg h(-1) for crop residues and dried cattle dung, influenced PM(2.5) emission factors which were 1.7-2 g kg(-1) at low burn rates but 5-9 gkg(-1) at higher burn rates. Total carbon accounted for 45-55% and ions and trace elements for 2-12% Of PM(2.5) mass. The elemental carbon (EC) content was variable and highest (22-35%) in particles emitted from low burn rate combustion (wood and jute stalks) but significantly lower (2-4%) from high burn rate combustion (dried cattle dung and rice straw). The mass absorption cross-section (MAC, m(2) g(-1)) correlated with EC content for strongly absorbing particles. Weakly absorbing particles, from straw and dung combustion, showed absorption that could not be explained by EC content alone. On average, the MAC of biofuel emission particles was significantly higher than reported measurements from forest fires but somewhat lower than those from diesel engines, indicating potential to significantly influence atmospheric absorption. Both for a given fuel and across different fuels, increased burn rates result in higher emission rates of PM(2.5), larger organic carbon (OC) content, larger average particle sizes, and lower MAC. Larger mean particle size (0.42-1.31 mu m MMAD) and organic carbon content, than in emissions from combustion sources like diesels, have potential implications for hygroscopic growth and cloud nucleation behavior of these aerosols. These measurements can be used to refine regional emission inventories and derive optical parametrizations, for climate modeling, representative of regions dominated by primary particles from biomass fuel combustion.