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Transport of people and goods has always been associated with the generation of some form of pollution, whether atmospheric, sound or visual. Managing the urban environment presents a major challenge: preserving environmental resources and also ensuring decent living conditions for the current population and for future generations. In the era of motorized and carbonized transport, vehicles are the main source of emission of atmospheric pollutants, mainly in large urban centers and important precursors of ozone. An important advance in minimizing vehicle emissions was the introduction of cleaner and additive fuels into the Brazilian market. The purpose of this paper is to study the effect of the Dienitro additive on the NO_x and CO emissions in buses of collective transport, Diesel S-50 exhaust gas recirculation (EGR) and S-10 with selective catalytic reduction (SCR) and EGR systems. Measurements of CO and NO_x gas emissions were carried out using a gas analyzer in S50 and S10 diesel buses with an EGR and SCR systems from a company operating in the collective transport of Biguaçu.

In this study, 20 measurements were performed without additives and 20 measurements with additivation in each bus, making it possible to calculate the average emission rate of CO and NO_x, pollutant gases with toxic effect.

The usage of Dienitro additive in diesel engines resulted in a significant reduction in the emission of polluting gases, carbon monoxide (CO) and nitrogen oxide (NO_x), thus being efficient in reducing the emissions of these gases.

The Dienitro additive was first tested on diesel engines by public transport buses, and there is great potential for reducing the emission of toxic gases.

Spark ignition (SI) engines are used in a wide area in the transportation industry, from road vehicles to piston-prop aircraft. On the other hand, the decrease in reserves of fossil fuels used in SI engines and the increase in greenhouse gas emissions makes the use of alternative fuels inevitable. In this paper, optimization of in-cylinder combustion and engine performance parameters by intake-charge conditions [i.e. intake-air temperature, injection timing and exhaust gas recirculation (EGR)] in a hydrogen (H₂)-fueled small SI engine is performed.

Experimental studies were performed at a 1,600 rpm engine speed of a single-cylinder, air-cooled engine having a stroke volume of 476.5 cm³, maximum output power of 13 HP and torque of 25 Nm. The hydrogen-fueled SI engine was operated by a lean air-fuel mixture (ϕ = 0.6) under wide-open throttle (WOT) conditions.

The findings of the paper show that improvements can be achieved in in-cylinder combustion, indicated engine performance, exhaust NO_x emissions with optimum intake-air temperature, the start of H₂ injection and the ERG rate.

It has been determined that a 32°C intake-air temperature, 395°C (bTDC) start of H₂ injection, and 5%–10% EGR rates are the most suitable values for the examined hydrogen fueled SI engine.

Hydrogen is a usable alternative fuel for SI engines used in a wide area from road vehicles to piston-prop aircraft engines. However, a number of problems remain that limit hydrogen fueled SI engines to some extent, such as backfire, a decrease of engine power, and high NO_x emissions. Therefore, it is appropriate to examine the effects of intake-charge conditions on in-cylinder combustion, engine performance, and NO_x emissions parameters in a hydrogen fuelled SI engine.

The different performance tests were conducted on diesel engine compression ignition (CI) mode and CRDi engine.

The CI engine was suitably modified to CRDi engine with Toroidal re-entrant combustion chamber (TRCC) and was run in dual-fuel (DF) mode. Hydrogen (H₂) was supplied at different flow rates during the suction stroke, and 0.22 Kg/h of hydrogen fuel flow rate (HFFR) was found to be optimum. Diesel and biodiesel were used as pilot fuels. The CRDi engine with DF mode was run at various injection pressures, and 900 bar was found to be optimum injection pressure (IP) with 10o before top dead center (bTDC) as fuel injection timing (IT).

These operating engine conditions increased formation of oxides of nitrogen (NOx), which were reduced by exhaust gas recycle (EGR). With EGR of 15%, CRDi engine resulted in 12.6% lower brake thermal efficiency (BTE), 5.5% lower hydrocarbon (HC), 7.7% lower carbon monoxide (CO), 26% lower NOx at 80% load as compared to the unmodified diesel engine (CI mode).

The current research is an effort to study and evaluate the performance of CRDi engine in DF mode with diesel-H₂ and BCPO-H₂ fuel combinations with TRCC.

This paper aims to present the effects of varying different operating parameters such as Start of Injection (9 to 21 deg bTDC), compression ratio (16 to 12.5), fuel injection pressure (400 to 1,400 bar) and exhaust gas recirculation (0 to 25 per cent) on the performance and emissions of the engine for constant engine speed of 1,600 rpm.

Simulation results were validated with experimental data available in the literature for baseline configuration. The effect of each parameter on the performance characteristics such as pressure and temperature, emission characteristics such as NO_x and soot are presented and discussed. Optimization has been carried out based on the regression equations developed from the simulation results to obtain the optimum set of the parameters to achieve the desired performance and emissions. Numerical simulations have been performed for the optimized set and compared with the reference engine.

Results of optimization showed that there was a simultaneous reduction in NO_x and soot while maintaining the same level of performance as that of the baseline case.

Based on the present work, it can be said that lesser emissions are achieved in terms of NO_x and soot while maintaining the same performance in terms of peak pressure.

The purpose of this paper is to find the pressure and the knocking phenomena. To get the pressure values, the butterworth bandpass filter was used and the potential of knocking was found by using peak-to-peak pressure values and also the species concentration. Cooled exhaust gas recirculation was the method used to minimize the knocking occurrence in the engine. Moreover, the effect of premixed methanol and start of engine (SOI) on knocking were also determined.

This paper deals with the compression ignition engine to investigate the unfavorable knocking behavior. The tests were carried out with the 3D model of engine fueled with waste cooking oil blended with TiO2. A number of tests were taken to find the pressure variation and the species concentration at eight different locations in the computational model.

In doing the tests, the positive intended outcome was achieved. From results, it is clear that the SOI and premixed methanol mitigated the knocking process.

The species concentration and pressure in the form of filtered signal were proved to be the ideal methods for evaluating the knocking event in the engine.

The purpose of this paper is to determine whether the altitude at which construction equipment operates affects or contributes to increased engine wear.

The study includes the evaluation of two John Deere PowerTech Plus 6,068 Tier 3 diesel engines, the utilization of OSA3 oil analysis laboratory equipment to analyze oil samples, the employment of standard sampling scope and methods, and the analysis of key Engine Control Unit (ECU) data points (machine utilization, Diagnostic Trouble Codes (DTCs) and engine sensor data).

At 250 h of engine oil use, the engine operating at 3,657 meters above sea level (MASL) had considerably more wear than the engine operating at 416 MASL. The leading and earliest indicator of engine wear was a high level of iron particles in the engine oil, reaching abnormal levels at 218 h. The following engine oil contaminants were more prevalent in the engine operating at the higher altitude: potassium, glycol, water and soot. Furthermore, the engine operating at higher altitude also presented abnormal and critical levels of oil viscosity, Total Base Number and oxidation. When comparing the oil sample analysis with the engine ECU data, it was determined that engine idling is a contributor for soot accumulation in the engine operating at the higher altitude. The most prevalent DTCs were water in fuel, extreme low coolant levels and extreme high exhaust manifold temperature. The ECU operating data demonstrated that the higher altitude environment caused the engine to miss-fire and rail pressure was irregular.

Many of the mining operations and construction projects are accomplished at mid to high altitudes. This research provides a comparison of how construction equipment engines are affected by this type of environment (i.e. higher altitudes, cooler temperatures and lower atmospheric pressure). Consequently, service engineers can implement maintenance strategies to minimize internal engine wear for equipment operating at higher altitudes.

The main contribution of this paper will help construction equipment end-users, maintenance engineers and manufacturers to implement mitigation strategies to improve engine durability for countries with operating conditions similar to those described in this research.

More stringent emission standards are being promulgated all over the world for regulating and decreasing the levels of emission more so caused from on-road vehicles and engines and for improving the air quality problems.

In this study, an attempt has been made to experimentally analyze the performance and emission characteristics of the premixed charge compression ignition (PCCI) mode assisted by a pilot injector.

The results indicate that brake thermal efficiency marginally decreases, and specific fuel consumption increases in all PCCI modes, and HC, CO emissions are higher in the case PCCI modes and oxides of nitrogen and soot levels are considerably reduced in the case of diesel PCCI-biodiesel and petrol PCCI-biodiesel modes.

As obtaining very lean homogenous mixture is hard, it becomes difficult to sustain PCCI mode over the operating range of varying speeds and loads to effectively control the PCCI combustion over the operating range.

Being a responsible human being, we all have the responsibility in keeping this world cleaner, free from all sort of pollution. In this regard, the concept of waste recycling and energy recovery plays a vital role in the development of any economy. This has led to resource conservation and pollution reduction.

The present work Jatropha oil methyl ester (JOME) was chosen as fuels for PCCI mode. Investigations were carried out with blends of JOME with diesel in PCCI combustion mode to evaluate the performance, combustion and emission characteristics of these fuels.

Homogeneous charge compression ignition (HCCI) engine is an advanced combustion method to use alternate fuel with higher fuel economy and, reduce NOX and soot emissions. This paper aims to investigate the influence of ethanol fraction (ethanol plus gasoline) on dual fuel HCCI engine performance.

In this study, the existing CI engine is modified into dual fuel HCCI engine by attaching the carburetor to the inlet manifold for the supply of ethanol blend (E40/E60/E80/E100). The mixture of ethanol blend and the air is ignited by diesel through a fuel injector into the combustion chamber at the end of the compression stroke. The experiments are conducted for high load conditions on the engine i.e. 2.8 kW and 3.5 kW maximum output power for 1,500 constant rpm.

It is noticed from the experimental results that, with an increase of ethanol in the blends, ignition delay (ID) increases and the start of combustion is retarded. It is noticed that E100 shows the highest ID and low in-cylinder pressure; however, E40 shows the lowest ID compared to higher fractions of ethanol blends. An increase in ethanol proportion reduces NOX and smoke opacity but, HC and CO emissions increase compared to pure diesel mode engine. E100 plus diesel dual-fuel HCCI engine shows the highest brake thermal efficiency compared to remaining ethanol blends and baseline diesel engine.

This experimental study concluded that E100 plus diesel and E80 plus diesel gave optimum dual fuel HCCI engine performance for 2.8 kW and 3.5 kW rated power, respectively.

Two 5W‐30 synthetic‐base phosphorus containing (commercial) and phosphorus‐free (P‐free) crankcase oils were tested for engine performance characteristics, engine emissions and poisoning effects of oil additives on a three‐way catalytic converter using engine dynamometer. The emission data of the two oils taken during engine operation were compared in the absence and presence of the catalytic converter. Surface characterization was used to determine the poisoning catalyst effect accumulated from the oil additives in the ceramic washcoat. Oil analyses were also used to examine the condition of the lubricant occurred during engine performance testing operation. The experimental engine performance tests indicated that the catalytic converter diminished the torque and power for the commercial and P‐free oils, whereas the specific fuel consumption increased for both oils in the presence of the catalytic converter.