Exhaust Emissions Research Articles

Exhaust emission and performance characteristics of coated CI engine fueled with hackberry biodiesel-diesel dual-fuel

Exhaust emission and performance characteristics of coated CI engine fueled with hackberry biodiesel-diesel dual-fuel

The response of daytime nitrate formation to source emissions reduction based on chemical kinetic and thermodynamic model

Particulate nitrate is an important component of particulate matter and poses a significant threat to the ecosystem and human health. The gas-phase formation pathway of nitrate is extremely important, which mainly comprises the NO2 oxidation process triggered by OH radicals and the nitrate partitioning process. The response of nitrate to source emission reduction during different pollution periods remains unclear. Here, we applied the chemical kinetic and thermodynamics model to explore the importance oxidation process and partitioning process during different pollution periods based on high-time resolution observation data. The result indicated that with the aggravation of pollution, the partitioning process gradually ceases to be a limiting step in the formation of nitrates. The results of the influencing factor analysis indicate that NO2 concentration and aerosol pH values play a more significant role in the formation of nitrates. Specifically, during the clean period, nitrate formation is sensitive to both NO2 concentration and pH values, but during the pollution period, it becomes sensitive only to NO2 concentration. By combining source apportionment, we explored the response of nitrate formation to source emission reduction, and the results showed that the control of vehicle exhaust emissions and coal combustion sources is more effective in mitigating nitrate pollution. Additionally, this study also emphasized the importance of early prevention and control of pollution sources. This research provides scientific evidence for the precise management and control of nitrates.

Machine learning based prognostics and statistical optimization of the performance of biogas-biodiesel blends powered engine

In this study, waste biomass-derived biogas was employed as the main fuel while the biodiesel-diesel blend was used as pilot fuel. This paper describes the development of a Decision Tree and Response Surface methodology-based statistical framework for prediction modeling and optimization. The compression ratio, fuel injection time, fuel injection pressure, and biogas flow rate were employed as controllable inputs, and brake thermal efficiency, peak combustion pressure, and exhaust emission were selected as responses. The experimental data for model development was gathered for the development of prediction models and optimization. The decision tree-based models were robust with almost negligible mean squared errors and R2 values of more than 0.9487 for all models. Response surface methodology-based optimized engine parameters were validated with the following results compression ratio was 17.9, fuel injection pressure was 225 bar, fuel injection timing was 26.3-degree crank angle after top dead center, and the biogas flow rate was 0.85 kg/h. Validation results were within 5 % of the model-optimized results. The prognostic models for all control factors were developed with decision tree-based machine learning with high predictive efficiency and low errors.

Experimental study of the effects of a particle filter in front of automotive radiator on its cooling performances and cooling drag

According to the World Health Organization (WHO), air pollution is the single greatest worldwide health risk especially in urban environments. In these areas, the vehicle traffic significantly contributes to the fine dust concentration in the ambient air. While the current legislation focuses mainly on the exhaust emission of vehicles, 85% of the overall fine dust emissions originating from brakes, tires, and road abrasion are not yet regulated. In this context, an integrated particulate filter system fitted into previously unused installation spaces in frontend of a vehicle in front of the radiator allows to compensate a part of the particle emissions of a vehicle try to reach the neutral emission. Add filter is not without consequences for the cooling performances. This study aims to assess the impact of the particulate filter system on the radiator cooling performances and cooling drag coefficient. An experimental setup was developed to characterize an automotive radiator with and without particle filter in terms of power and velocity distribution. Cooling capacity of the radiator depends clearly of the airflow through the radiator. Filter increases the pressure drop and decreases airflow. Hence, the heat power exchange can be reduced up to 10% for a pressure drop level almost twice. The airflow inlet inside engine compartment is not beneficial for aerodynamic aspect. By increasing pressure drop, the cooling drag coefficient can be reduced up to 10% when a filter covers entirely the radiator surface. The results indicate that the filter affects the cooling capacity of the radiator, which can require modifications to the cooling system strategy.

A study on the influence of utilizing hydrogen at fuelling spark ignition engines

Abstract In the last 30 years, remarkable progress has been made in reducing pollutant emissions and fuel consumption in conventional internal combustion engines. Active and passive methods of reducing exhaust emissions have caused them to decrease significantly over the level of the 1980s. However, the problems of air pollution and the greenhouse effect are far from being solved. International organizations and institutions are pushing for measures to reduce emissions, especially the implementation of “zero-emission” (ZEV) vehicles. Due to its excellent combustion properties and the very low pollutant emissions resulting from its combustion, hydrogen is seen as an alternative fuel of the future. Hydrogen can be used as a fuel in two ways: in internal combustion piston engines or in fuel cells. Research into the use of hydrogen as a fuel for spark ignition engines is divided into two directions: additive fuel or a total gasoline substitution with hydrogen. Compared to the gasoline-powered engine, the fully hydrogen-powered engine runs more economically at low loads but it can create a decrease of performance at high loads due to the high volumes of space needed in the combustion chamber. Because of the very low density, high volumes of hydrogen are difficult to storage, requiring also high pressure, so running only on hydrogen wouldn’t be practical. Combining the advantages of the two fuels came the use of gasoline with addition of hydrogen. An important aspect is that emissions are significantly reduced due to the very good combustion properties of hydrogen and the high diffusivity that helps to form a homogeneous mixture. This paper presents aspects of fuelling a spark ignition engine with gasoline and hydrogen. The influence of hydrogen on the cylinder mixture, on the energy and emissions of the engine is analysed. We will focus on: engine power, fuel consumption, the level of pollutant emissions and greenhouse gases, at the studied regimes.

Experimental investigation of performance, emission, and combustion characteristics of a diesel engine using blends of waste cooking oil-ethanol biodiesel with MWCNT nanoparticles

In this study, blends of 5 % and 10 % ethanol with waste cooking oil biodiesel are mixed with Multi-Walled Carbon Nanotubes (MWCNT) at a concentration of 30 ppm. MWCNTs, known for their high surface area and unique properties, are added to potentially enhance combustion efficiency and reduce emissions. These blends are then tested in a diesel engine to evaluate their performance, emission and combustion characteristics using Design of experiment technique. After conducting various experiments and analyses, the blend of 20 % biodiesel, 10 % ethanol, and 30 ppm MWCNT was identified as the most optimal due to its favorable engine characteristics. Brake Thermal Efficiency (BTE) was increased from 3.1 % to 3.4 % with the addition of MWCNTs, indicating enhanced fuel efficiency. Moreover, average Fuel Consumption is decreased from 2.2 % to 2.5 %, suggesting improved fuel utilization. Using MWCNT 30 ppm in B20 ethanol blends (MWCNT 30 ppm B20+E10) resulted in 35 % reduction in nitrogen oxide (NOx) emissions, 37 % reduction in CO emissions and 39 % reduction in HC emissions. Hence MWCNTs demonstrated effectiveness in mitigating harmful exhaust emissions The optimized values for all parameters fall within acceptable ranges, indicated successful optimization using Response surface methodology. Additionally, statistical analysis reveals that the machine learning- XGBoost model outperformed all other advanced machine learning models across all tested metrics, including MSE, MAE, and R-square.

Description and validation of Vehicular Emissions from Road Traffic (VERT) 1.0, an R-based framework for estimating road transport emissions from traffic flows

Abstract. VERT (Vehicular Emissions from Road Traffic) is an R package developed to estimate traffic emissions of a wide range of pollutants and greenhouse gases based on traffic estimates and vehicle fleet composition data, following the EMEP/EEA methodology. Compared to other tools available in the literature, VERT is characterised by its ease of use and rapid configuration, while it maintains great flexibility in user input. It is capable of estimating exhaust, non-exhaust, resuspension, and evaporative emissions and is designed to accommodate future updates of available emission factors. In this paper, case studies conducted at both urban and regional scales demonstrate VERT's ability to accurately assess transport emissions. In an urban setting, VERT is integrated with the Lagrangian dispersion model GRAMM–GRAL and provides NOx concentrations in line with observed trends at monitoring stations, especially near traffic hotspots. On a regional scale, VERT simulations provide emission estimates that are highly consistent with the reference inventories for the Emilia-Romagna region (Italy). These findings make VERT a valuable tool for air quality management and traffic emission scenario assessment.

Effects of ammonia energy ratio and PODE injection timing on combustion and emissions in a PODE/ammonia RCCI engine

The application of ammonia as an alternative carbon-free fuel has attracted increasing attention. In this paper, the effects and mechanisms of ammonia energy ratio (AER) and polyoxymethylene dimethyl ethers (PODE) injection timing on the combustion and emissions characteristics of a PODE/ammonia RCCI engine are investigated by both experimental and numerical methods. Results show that increasing AER from 10% to 40% leads to the delayed low temperature heat release (LTHR) due to reduced OH radical generated by PODE and the competition between PODE and ammonia for OH radical consumption. The larger AER increases the indicated thermal efficiency (ITE) by lowering combustion temperature and reducing heat transfer losses at the cost of higher hydrocarbon (HC), carbon monoxide (CO), and unburned NH3 emissions. The reduction of fuel-based nitrogen oxide (NOx) emissions with a larger AER is attributed to the enhanced in-cylinder thermal denitrification reactions. The delayed start of injection (SOI) from −60 °CA ATDC to −45 °CA ATDC leads to the higher peak in-cylinder pressure and temperature, resulting in the larger heat transfer losses and lower ITE. The impact of retarding SOI on NOx is insignificant under the combined effect of more thermal NO formation, less fuel-based NO generation, and weakened denitrification reactions. Additionally, nitrous oxide (N2O) shows dominant effects on the total greenhouse gas (GHG) emissions, and increasing AER or advancing injection timing produces more GHG. Under low loads and low AERs, although the introduction of ammonia helps to improve ITE, more researches are required to further reduce exhaust emissions.

Retrofit of a Marine Engine to Dual-Fuel Methane–Diesel: Experimental Analysis of Performance and Exhaust Emission with Continuous and Phased Methane Injection Systems

Shipping is a highly energy-intensive sector, and fleet decarbonization initiatives can significantly reduce greenhouse gas emissions. In the short-to-medium term, internal combustion engines will continue to be used for propulsion or as electricity generators onboard ships. Natural gas is an effective solution which can be used to mitigate greenhouse gas emissions from the marine sector. Considered to be a transitional fuel, it can provide a potential reduction in CO2 emissions of around 20–30%, compared with conventional marine fuels. This work investigated the influence of diesel-injection strategies on the performance and emissions of a single-cylinder prototype compression-ignition engine for marine applications, retrofitted to run as a Low-Pressure Dual-Fuel Engine using natural gas. Two different injection systems were used: a mass flow controller enabling continuous-mode gas feeding, and a Solenoid-Operated Gas Admission Valve for marine applications, the latter allowing phased natural-gas injection. Experimental tests were focused on partial-load conditions, which are critical for dual-fuel engines, with a natural gas/diesel mass ratio of 4:1. Phased injection resulted in reductions in fuel consumption, compared to continuous mode, of up to 11%. Further experiments demonstrated reductions in fuel consumption of up to 20.7% (in equivalent diesel); on the other hand, the unburned hydrocarbon emissions which resulted were an order of magnitude larger than the reference values for full diesel, reducing the benefits in terms of greenhouse gas emissions, with a reduction in Global Warming Potential of only 3% compared to full diesel.

Exhaust Gas Flow Study of Electric Turbo Compounding (ETC) to Determine the Potential Electrical Energy Recovery from Exhaust Emission

Electric turbo compounding (ETC) emerges as a pivotal energy recovery solution, seamlessly combining an advanced turbocharger with a high-speed generator to harvest electrical energy from exhaust gas dynamics. This research delves into the practical application of ETC in vehicles, employing a comprehensive approach blending simulation techniques with experimental validation. The investigative process involves meticulous data collection on vehicle muffler dimensions, subsequent device modelling based on this data, and rigorous flow simulations, followed by thorough analysis. The study's key findings highlight a noteworthy 9% increase in engine back pressure at 850 rpm, counterbalanced by a 7% reduction at 2000 rpm. Despite the integration of the ETC mechanism, electric current measurements remain consistently within the range of 1.4 to 1.6 amperes at 1200-2000 rpm. This research not only unveils the tangible effects of ETC on engine performance but also underscores its viability as an efficient energy recovery solution in the automotive sector, setting the stage for advancements in sustainable transportation.

Modelling and experimental analysis of Aero-Engine performance and exhaust emission characteristics Fueled with green fuel blends

This study aims to assess the impact of using green fuel in place of biodiesel on the performance and exhaust emissions of air-breathing engines. GasTurb 13 is utilized to forecast the engine’s performance (kingTech 180 k turbojet engine). Catalytic deoxygenation of vegetable oils produces green diesel, offering an alternative to biodiesel. Physiochemical properties of GD blends (PME30GD20, PME20GD30, PME10GD10) were analyzed, and GasTurb-13 software predicted engine performance and emissions, validated with experimental data. The results show that GD10PME10 exhibited higher density (767.6 g/m3) than pure green fuel, while viscosity dropped by 53.85 % compared to PME. GD outperformed Jet-A1 by 0.74 % in heating value, with GD10PME10 having the highest at 42.63 MJ/kg. Engine performance measures included thrust, mass fuel flow, thrust-specific fuel consumption, and exhaust gas temperature. GD10PME10 showed a 12.5 % thrust increase and the lowest TSFC (95 g/kN.s) at 80,000 RPM compared to Jet-A1. GD20PME30 achieved the lowest EGT (550 °C) at the same RPM. Regarding emissions, GD20PME30 emitted the lowest CO (100,000 RPM, 150 ppm) and 0.5 % less CO2 (90,000 RPM) than Jet-A1. GD10PME10 produced the lowest NOx (12.5 ppm) at maximum speed, while Jet-A1 emitted the least NOx (7.5 ppm) at 120 k RPM. Overall, the data suggested that green fuel might increase the physiochemical properties of biodiesel blends, hence improving the fuel’s capacity to burn more effectively in aero-engines.

Computational fluid dynamic analysis of the effect of inlet valve closing timing on common rail diesel engines fueled with butanol–diesel blends

The inlet valve closing (IVC) timing plays a crucial role in engine combustion, which impacts engine performance and emissions. This study attempts to measure the potential to use n-butanol (Bu) and its blends with the neat diesel in a common rail direct injection (CRDI) engine. The computational fluid dynamics (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol–diesel blends (0%–30% by volume) for variable valve timings. An experimental study is carried out using standard valve timing and blends to validate the CFD model (ESE AVL FIRE). After validation, the CFD model is employed to study the effect of variable valve timings for different n-butanol–diesel blends. Extended coherent flame model-3 zone (ECFM-3Z) is implemented to conduct combustion analysis, and the kappa–zeta–f (k–ζ–f) model is employed for turbulence modeling. The inlet valve closing (IVC) time is varied (advanced and retarded) from standard conditions, and optimized valve timing is obtained. Advancing IVC time leads to lower cylinder pressure during compression due to reduced trapped air mass. The brake thermal efficiency (BTE) is increased by 4.5%, 6%, and 8% for Bu10, Bu20, and Bu30, respectively, compared to Bu0. Based on BTE, optimum injection timings are obtained at 12° before the top dead center (BTDC) for Bu0 and 15° BTDC for Bu10, Bu20, and Bu30. Nitrogen oxide (NOx) emissions increase due to complete combustion. Due to IVC timing, further carbon monoxide and soot formation decreased with blends and had an insignificant effect.

Local contribution of road traffic and residential biomass burning to black carbon aerosols – Modelling and validation

Black carbon (BC) is a harmful pollutant to human health and the environment. The aim of this paper is to evaluate the local contribution of road traffic and residential biomass burning to BC pollution levels at urban scale by implementing an integrated modelling approach with high spatial and temporal resolution. The traffic emission was extended to include BC emission factors considering road network as line emission sources. A new module to calculate emissions from residential biomass burning was developed based on the heating degree days methodology and local surveys. The modelling approach implemented in Coimbra, Portugal, was validated with observations collected during a six-month monitoring campaign at urban traffic and urban background stations using thermo-optical and optical methods. At the traffic station, modelling results showed that 86% of BC concentrations are related to traffic activity, which are mostly due to hot exhaust emissions (76%). Nevertheless, biomass burning has a significant contribution in the whole urban area during winter. The results of monthly average BC concentrations obtained from dispersion modelling revealed a contribution from local road traffic and residential biomass burning emissions of around 4 μg m−3 at both monitoring sites during the coldest period, but this contribution was two times higher for the hotspots identified within the urban area. Moreover, hourly values at hotspots obtained from the modelling may achieve 85 μg m−3, thus stressing the importance of spatial and temporal analysis with high resolution. The validation approach applied in this work highlight the need for more transparency in defining “black carbon” reported by modelling to ensure comparability with measurements obtained by different techniques.

The mechanism and effect factors of the combustion cycle‐to‐cycle variations in the spark ignition engine

AbstractThe combustion cycle‐to‐cycle variations (CCV) are the typical combustion phenomena in the internal combustion engine, which will not only affect the combustion efficiency, heat‐work conversion process, and emission formation in the cylinder, but also cause the output torque and power fluctuation, resulting in unstable and even misfire. These phenomena are particularly evident in the spark ignition (SI) engine, especially at idle, acceleration, and high exhaust gas recirculation conditions. Consequently, it is quite important to explore the internal relationship and correlation mechanism between the CCV and the affecting factors. This paper comprehensively reviewed the fundamental reasons and mechanisms of CCV of the SI engine. In addition, the characteristic parameters and characterization methods of the CCV, the laws and influencing factors of the CCV, and the numerical simulation methods of the CCV were introduced in detail to quantitatively analyze the performance, combustion, and emissions characteristics of the SI engine. Each research direction is discussed in detail in various sections. The research status of the CCV of the SI engine from the experimental and numerical simulation aspects was also presented and discussed. Lastly, effective methods and strategies were proposed to improve the combustion process and fuel economy, and reduce exhaust emissions of the SI engine for high efficiency and clean combustion.

Enhancing reactivity-controlled compression ignition engine performance: A response surface methodology approach with ammonium hydroxide-waste cooking oil biodiesel optimization

The focus on ammonium hydroxide, biodiesels and their combustion technology has garnered significant attention in pursuing carbon-neutral and carbon-free fuels to address greenhouse gas emissions (GHG) and mitigate global warming. Low-temperature combustion (LTC) has been introduced as an alternative method to conventional compression ignition (CI) combustion. Reactivity controlled compression ignition (RCCI) can be achieved by introducing highly reactive waste cooking oil methyl ester (WCOME) oil directly into the manifold in intervals of 10% energy and injecting low-reactive ammonium hydroxide at 20%–50%. Utilizing the response surface methodology (RSM) approach, it was determined that for optimal operation in RCCI mode, an ideal ammonium hydroxide energy sharing (AHES) of 43% would account for the varying parameters and their effects on emissions and performance. The results of the experiments predicted a brake thermal efficiency (BTHE) of 34.85% and a brake specific energy consumption (BSEC) of 10.69 MJ/kWh. Meanwhile, a notable decrease in exhaust emissions was observed for HC, CO, CO2, NO x and smoke by 41.54%, 38.89%, 48.89%, 51.27% and 65.80% respectively when compared to conventional biodiesel combustion (CBC). The experimental result at maximum load operation with an AHES of 50% indicates that RCCI combustion led to an increase in thermal efficiency from 30.36% to 35.42%, and the in-cylinder pressure and heat release rate dropped from 83.42 bar to 59.64 bar and 78.68 kJ to 60.92 kJ, respectively. There was a significant reduction in HC, CO, CO2, NO x and smoke emissions recorded as 58.76 ppm, 0.11%v, 1.61%v, 442 ppm and 6.64 N, respectively, compared to CBC.

Ensuring Operational Performance and Environmental Sustainability of Marine Diesel Engines through the Use of Biodiesel Fuel

This article considers the issues of ensuring operational performance and environmental sustainability of marine diesel engines by using biodiesel fuel. This research was conducted on 5S60ME-C8 MAN-B&W Diesel Group and 6DL-16 Daihatsu Diesel marine diesel engines, which are operated using RMG380 petroleum fuel and B10 and B30 biodiesel fuels. The efficiency of biofuel usage was assessed based on environmental (reduced nitrogen oxide concentration in exhaust gases) and economic (increased specific effective fuel consumption) criteria. It was found that the use of B10 and B30 biofuels provides a reduction in nitrogen oxide concentration in exhaust gases by 14.71–25.13% but at the same time increases specific effective fuel consumption by 1.55–6.01%. Optimum fuel injection advance angles were determined that ensure the best thermal energy, economic and environmental performance of diesel engines. The optimum angle of biofuel supply advance is determined experimentally and should correspond to the limits recommended by the diesel engine operating instructions. It has been proven experimentally that the use of biofuel increases the environmental sustainability of marine diesel engines by 13.75–29.42%. It increases the diesel engines environmental safety in case of emergency situations as well as accidental and short-term emissions of exhaust gases with an increased content of nitrogen oxides into the atmosphere phenomena that are possible in starting modes of diesel engine operation as well as in modes of sudden load changes. It is the increase in the environmental friendliness of marine diesel engines in the case of using biofuel that is the most positive criterion and contributes to the intensity of biofuel use in power plants of sea vessels.

New NOx and NO2 vehicle emission curves, and their implications for emissions inventories and air pollution modelling

Emissions of NOx and primary NO2 from road transport sources are highly influential in NO2 exposure at both local and regional scales; quantifying these accurately is therefore an important but challenging component of emissions inventory and air pollution model development. Results are presented from an urban air pollution model, after creation of new speed-emissions curves for NOx through the combination of available vehicle drive cycles and nearly 500,000 UK-based remote sensing measurements of exhaust emissions. Vehicle power-based relationships are applied to 1 Hz drive cycle datasets, with random sampling of the outputs allowing generation of the new curves. These demonstrate significantly higher emissions than those predicted by existing curves for most Euro VI HGVs, and among successive petrol and diesel passenger cars; this may be partly explained by relatively low UK ambient temperatures, as well as an underestimation of the level of tampering with HGV SCR systems. Implementation of the curves in a detailed emissions inventory for London, UK in 2019 leads to substantially improved air pollution model performance for NOx/NO2; normalised mean bias reduces in magnitude, changing from −0.18 to +0.01 for NOx and −0.12 to +0.01 for NO2. The curves developed are widely applicable, and the novel approach outlined has the potential to improve source apportionment and future model predictions under differing policy scenarios, produce better exposure estimates for health-related studies and revise NOx emissions budgets for compliance with the NEC Directive, all of which are important for the development of mitigation policies.

Effects of in utero benzo[a]pyrene exposure on the testis of rats during puberty and the protective effect of atorvastatin.

Benzo[a]pyrene (BaP) is a contaminant that is generated in the environment through processes such as smoke, incomplete combustion of fossil fuels, vehicle exhaust emissions, entry into the body is through inhalation, and consumption of contaminated food. It is an omnipresent environmental pollutant with unavoidable exposure. BaP metabolites are observed in the male reproductive system, especially in the testes and epididymis of animals, and are responsible for reduced testicular and epididymal function. The protective effect of atorvastatin (ATV) on testicular damage was investigated previously. The aim of the present study was to investigate the protective effect of ATV on testicular toxicity induced by benzo[a]pyrene (BaP) during pregnancy in Wistar rats. This experimental laboratory study involved 40 adult rats, divided into seven groups and maintained under standard environmental conditions. The groups received different diets [control, corn oil, ATV (10 mg/kg), BaP (10 and 20 mg/kg), and ATV + BaP (10 and 20 mg/kg)] at gestation Days 7-16, orally. Male offspring were examined 10 weeks after birth. Testis and serum samples were collected, and testosterone level, malondialdehyde (MDA), and glutathione (GSH) were measured. Histological and immunohistochemical assays were performed under a light microscope. Statistical analysis was conducted using SPSS, with analysis of variance and Tukey tests to assess significant differences between groups. ATV significantly reduced MDA, a marker of lipid peroxidation and oxidative stress in rat testes following BaP administration. Treatment with ATV at doses of 10 mg/kg increased GSH levels, correcting disruptions in the antioxidant system caused by BaP. Testosterone concentration in rats treated with ATV and BaP substantially prevented the decrease induced by BaP. Histomorphometry revealed that ATV significantly prevented the detrimental effects of BaP on the thickness of spermatogenic epithelium and the diameter of seminiferous tubules. Under ATV treatment, testicular tissue histopathology improved, and spermatogenesis returned to a almost back to normal state. Caspase-3 expression decreased, and apoptosis activity in testicular tissue improved under ATV treatment, indicating a positive effect of ATV in reducing apoptotic damage caused by BaP. In conclusion, exposure to BaP can induce oxidative stress-related damage to testicular tissue, as evidenced by an increase in MDA levels, which ATV treatment can mitigate. Additionally, ATV enhances intracellular antioxidant GSH and protects the testes against BaP-induced damage while increasing testosterone levels, which are reduced due to exposure to BaP.

Educating Engineers on the Use of Renewable Ethanol Fuel as a Drop-in Replacement for Gasoline in Small Engines

The use of high-blend ethanol fuels to reduce emissions produced by on-road vehicles has been extensively studied. However, much less research has been done to study the effect of operating small off-road engines on high-blend ethanol fuel as a drop-in replacement for gasoline. Most small engine manufacturers only certify proper operation on low ethanol blends such as E10 (10% ethanol, 90% gasoline by volume). Most engineering students are unaware of the benefits that can be achieved when using high-blend ethanol fuel in small engines without substantial modifications. In this study, students conducted performance testing and analysis of a small engine using a dynamometer and a raw exhaust emissions analyser. The exhaust emissions and performance of the engine were evaluated using the U. S. Environmental Protection Agency (EPA) 6-mode duty cycle for small recreational engines (under 19 kW). Testing and analysis followed the recommendations of the SAE J1088 recommended practice. Students were motivated by the contemporary nature of the project and the use of commercially available equipment for testing. Further, students learned about the use of standardized testing to demonstrate the performance and emissions results.

Developing a system for the real-time collection and analysis of mobile vehicle emission data

In this study, an integrated system for remotely monitoring air pollution data was developed. This system combines vehicle exhaust emission data with driving information. It comprises an exhaust extraction device (EED), an improved On-Board Diagnostic II (OBDII) device, a mobile app, and a backend server database. The EED detects exhaust gases such as NOx, COx, and PM2.5 and transmits this information to the OBDII device through 2.4G communication. The OBDII device gathers vehicle driving information through a CAN 2.0 interface, integrates this information with vehicle exhaust emission data, and transmits the integrated information to the app through Bluetooth. The app forwards the integrated data to the backend database through 4G/5G communication for storage. Overall, this system provides a platform for the comprehensive collection, analysis, and application of big data pertaining to vehicle pollution sources and driving behavior. Analysis of actual driving experiments involving three vehicles revealed a correlation of over 80 % between vehicles’ revolutions per minute and CO2 and PM2.5 emissions, indicating that driving behaviors affect vehicle exhaust emissions. In summary, the proposed system not only stores relevant driving information in real time but also provides a platform for the future analysis of driving behavior and vehicle exhaust emissions.