Decrease In Soot Emissions Research Articles

Intelligent Decision-Based Hydrogen-Biodiesel engine to improve engine performance

This study highlights the urgent need to improve the performance of biodiesel engines in light of the growing environmental challenges that are mostly brought on by a rise in vehicle usage. It introduces a novel approach by combining vegetable oil and hydrogen as an alternative fuel and using a Decision Elman Neural Framework (DENF) to adjust engine settings. Through the implementation of an all-inclusive strategy that includes data gathering, pre-processing, feature analysis, and real-time tracking, the system aims to increase engine performance while reducing environmental impact. A comparison with traditional techniques highlights the improved engine performance and reduced emissions that the suggested method achieves. Combining vegetable oil and hydrogen with DENF appears to be a key tactic for increasing engine efficiency and promoting sustainability in biodiesel engines. The data-driven approach results in a significant 7.4% improvement in engine performance and a 2.1% decrease in peak emissions. On the other hand, it is linked to a 19.8% increase in CO emissions and a 5.6% decrease in soot emissions, indicating better engine performance and a sustainable environment.

Multi-objective optimization of emission parameters of a diesel engine using oxygenated fuel and pilot injection strategy based on RSM-NSGA III

In this work, a diesel engine fueled with PODE3/n-butanol/diesel blends at high altitudes was optimized using the RSM-NSGA III hybrid optimization methodology to achieve a reduction in emissions. The target parameters of the optimization were soot, NOx, and HC emissions, and the decision variables were the mass ratio of pilot injection (MRPI), pilot injection timing (PIT), mass ratio of PODE3 (MRP) and mass ratio of n-butanol (MRB). Firstly, a three-dimensional simulation model of the CI engine was built in CONVERGE, and the model was verified through experiments. Secondly, the effects of the pilot injection strategy, also known as the pre-injection strategy, on the combustion characteristics of the CI engine were analyzed. Then, an experimental design based on Box-Behnken Design (BBD) was conducted and a mathematical model of the target parameters was obtained using RSM. Finally, the mathematical model of RSM was optimized using NSGA III to obtain the Pareto frontier, and the optimal solution was selected from the Pareto frontier using TOPSIS. The results showed that a suitable pilot injection strategy helped alleviate the problem of low cylinder pressure (CP) and high soot and HC emissions from the CI engine at high altitudes. The soot and HC emissions exhibited a decreasing and then increasing trend as the PIT advanced. As MRPI increased, both soot and HC emissions decreased. The NOx emissions showed the opposite trend. Compared with the non-optimized results, at an altitude of 2000 m, the optimized engine exhibited a 65.29% decrease in soot emissions, a 24.7% increase in NOx emissions, and a 74.94% decrease in HC emissions. Compared with the non-optimized results, at an altitude of 4000 m, the optimized engine demonstrated a 54.70% decrease in soot emissions, a 15.71% increase in NOx emissions, and a 65.78% decrease in HC emissions. This research will contribute to the application of oxygenated fuels in plateau diesel engines and the optimization of plateau diesel engines.

Comprehensive comparison of single-stage and novel two-stage hydrogen direct injection strategies on the combustion and thermodynamic performance of X-type rotary engine using gasoline-hydrogen fuel

In this paper, the CFD simulation model of a high-efficiency X-type rotary engine using premixed gasoline and hydrogen direct injection is established. The effect of hydrogen injection timing on combustion, pollutant emissions, and thermodynamic performances is investigated under hydrogen single-stage direct injection (HSDI). Furthermore, a novel hydrogen two-stage direct injection (HTDI) strategy using different first injection mass fractions (FIMF) and the same total injection pulse width of 3.5 °CA is proposed for improving combustion performance in the later phase under HSDI. The results show that the hydrogen injection timing of 290 °CA presents a 6.09% higher indicated thermal efficiency than that of 270 °CA under HSDI. The delay of the hydrogen injection timing leads to a decrease in soot emission. The optimal HTDI strategy is obtained at the FIMF of 60%, which shows a 6.35% higher combustion efficiency and a 0.89% higher indicated thermal efficiency than the optimal HSDI.

Numerical Assessment of Combustion Behavior and Emission Formations in an Ultrasonic-Assisted Ignition Engine.

By effective utilization of the dynamic mesh and coordinate transformation techniques, an ultrasonic horn is physically integrated in the chamber of an internal combustion engine. The consequences of multiple ultrasonic-fed strategies on the flow field, combustion process, and emission formation under the same working conditions are studied by numerical simulation. Based precisely on the bench test data, GT-Power and CONVERGE set up the original engine one-dimension (1d) and three-dimension (3d) simulation models. The chamber pressure and heat release rate of the 1d and 3d models under a full load condition of 3000 r·min-1 were validated, and the maximum relative error is less than 5%, proving the accuracy of the model. By reforming the 3d numerical model, ultrasonics is added to the gasoline engine's combustion chamber. Six different ultrasonic-fed schemes with 20 kHz amplitude of 30-300 μm are typically selected for in-depth research. The larger the amplitude, the stronger the turbulent kinetic energy (TKE), and the maximum TKE exceeds 46.6% at the ignition time. Stronger TKE can energetically encourage the generation of OH, O, and H radicals and improve the combustion reaction rate, and the peak pressure (PMAX) is increased by 1.9 MPa compared with scheme No. However, NOX and HC emissions gradually increase, reaching a maximum of 32.4 and 43.8%, respectively, while CO and soot emissions decrease, reaching a maximum of 11.4 and 11%, respectively. Four groups of ultrasonic-fed schemes with an amplitude of 100 μm and frequency of 20-50 kHz are scientifically studied. The findings indicated that the TKE level steadily increases as the frequency increases and the in-cylinder TKE increases by 16.4% at ignition time. The increase in ultrasonic frequency can promote the generation of active free radicals and meaningfully improve the combustion reaction rate to a certain extent. The PMAX can be increased up to 1 MPa compared with scheme No. At the same time, the NOX, HC, and soot also increased considerably, reaching 31.8, 17.9, and 21.9%, respectively. The CO showed a downward trend but gradually slowed, with a maximum decline of 6.5% at 20 kHz. The above simulation analysis is based on the full load condition of 3000 r·min-1, sufficiently proving that ultrasonics has a regulation effect on emissions and can achieve specific emissions through later optimization.

Combustion Characteristics of Diesel Methanol Blended Fuel Ship Engines

With increasingly stringent fuel emission control in some river traffic control zones and inland waters, this paper addresses the problem of substandard diesel fuel emissions, relying on the theoretical basis of numerical simulation of diesel engine in-cylinder combustion. The combustion and emission characteristics of diesel-water-mixed methanol blended fuel are simulated and analyzed based on the AVL FIRE software. The combustion model of the diesel engine was established, and the changes of in-cylinder pressure, temperature, heat release rate, and emission concentration were investigated for D85W10, D85W15, and D85W20 blends respectively, which were compared with diesel. The results show that as the proportion of water in the fuel mixture increases, the in-cylinder temperature gradually increases, the in-cylinder pressure slightly decreases, the heat release rate does not change much, and the NO and Soot emissions decrease.

Blending n-octanol with biodiesel for more efficient and cleaner combustion in diesel engines: A modeling study

Biodiesel has become a popular alternative fuel to fossil diesel. However, compared to conventional diesel engines, the adoption of pure biodiesel often leads to higher NOx though soot emissions can be reduced. In this study, the alcoholic fuel n-octanol was chosen as the blending fuel in biodiesel. The modeling study was carried out to investigate the effects of blending n-octanol on the combustion characteristics and emissions formation process in a diesel engine. At first, a multi-component reaction mechanism involving 115 species and 489 reactions was constructed to better predict the combustion process of biodiesel and n-octanol. This mechanism was then coupled with KIVA-CHEMKIN to implement a three-dimensional simulation of the engine. The developed mechanisms and adopted models were validated under a variety of conditions. At last, to examine the effects of n-octanol, simulations were carried out by gradually increasing the percentage of n-octanol from 0% to 100% with an interval of 10%. Analysis of the simulation results revealed that blending more n-octanol with biodiesel could lead to a prolonged ignition delay. Due to the high latent heat of vaporization of n-octanol, the temperature at the initial stage of combustion can be reduced which subsequently mitigated the formation of NOx. The higher oxygen content of n-octanol was beneficial for the improvement in power output and the decrease of soot emissions. Overall, B20/O80 blends were found to be capable of achieving more efficient and cleaner combustion in the diesel engine at both speeds.

A comparative study on the combustion and emissions of a non-road common rail diesel engine fueled with primary alcohol fuels (methanol, ethanol, and n-butanol)/diesel dual fuel

Primary alcohol fuels are the most promising fuels for diesel engines, thanks to their low emissions and easy adaptability to engine technologies. In this paper, the effects of the addition of methanol, ethanol, and n-butanol on the combustion characteristics and performance of a common rail dual fuel engine with diesel direct injection and alcohol fuel port injection are examined, followed by a comparative analysis of the test results.The test engine was operated at the maximum torque speed of 2500 rpm, and with a mean effective pressure (IMEP) of 0.75 MPa. The engine performance was analyzed for different alcohol/diesel fuel mixtures by using five alcohol substitute percentages (ASPs): 0% (pure diesel), 10%, 20%, 30%, and 40%. The experimental results demonstrate that slower flame development and faster flame propagation can be obtained by mixing any of the three alcohol fuels with diesel, compared with the pure diesel. With an increased ASP, the coefficient of variation of IMEP (COVIMEP) and the brake thermal efficiency (BTE) decreased, and the ringing intensity (RI) first increased and then dropped. The addition of primary alcohol fuels in the dual-fuel mode can also increase the total hydrocarbon (THC) and nitrogen oxide (NOX) emissions, but the carbon monoxide (CO) and soot emissions decrease. The comparative analysis indicated that the addition of methanol has the lowest COVIMEP and RI and the highest BTE among the three alcohol fuels. Adding methanol produces the lowest CO, NOX, and soot emissions and the highest THC emissions among the three alcohol fuels.

Combustion performance and mechanisms of the fuel/air mixture in a new separated swirl combustion system

To improve air efficiency in the combustion chamber, a new separated swirl combustion system (SSCS) was developed and is proposed herein. The SSCS performance was validated against a double swirl combustion system (DSCS) in an experimental test with a single-cylinder diesel engine. The experiment results show that the SSCS effectively reduces fuel consumption and soot emission, with a maximum decrease in fuel consumption of 5.41% (when the effective power was 17 kW) and a maximum decrease in soot emission of 20.48% (when the effective power was 43 kW). Then, simulation was used to investigate and reveal the mechanisms behind the fuel/air mixture in the chamber. The simulation results show that the angular fuel sprays collide with the unique circular ridges in the SSCS, which improves air utilization in the chamber and accelerates the fuel/air mixture, reducing soot emission.

Computational Combustion and Emission Analysis of Biodiesel in a Variable Compression Ratio Engine

The aim of the present study is to analyse the combustion characteristics, performance and emission parameters of a variable compression ratio (VCR) diesel engine experimentally and numerically using soybean methyl ester (SME) biodiesel. Initially the engine is fed with diesel to capture the basic data, and then SME was tested as 20 % blend (B20), as 40% blend (B40) and as pure bio-fuel (B100). The experimental investigations are followed by a computational combustion and emissions analysis of diesel engine which is done by using the CFD software (ANSYS FLUENT 13). The combustion, performance and emissions parameters are evaluated by operating the engine at four different compression ratios of 15, 16, 17.5 and 19 and varying the load from 0 kW to 4.4 kW with 1.1 kW step. It is observed that peak pressure is closer to TDC when SME blends is increased. SME blend has earlier combustion start because of the advancement in the injection timing, shorter delay time. Increasing mixing ratio of biodiesel is found to decrease BTE slightly and increases the BSFC. Remarkable decrease in UHC and CO emissions as the ratio of SME is increased due to the complete combustion of biodiesel with presence of more oxygen in the combustion chamber. The measured BSN for B20, B40, and B100 SME was less than that of diesel fuel by 20.44%, 35.78%, and 48.3% respectively. It is inferred from the combustion analysis that as the compression ratio increases from 15 to 19 a decrease in smoke intensity, UHC, and CO, but it increases the emission of NOx. Both turbulent kinetic energy and turbulent dissipation rate were decreased as the percentage of SME increased by 10.84% and 2.01% respectively. The increase in compression ratio from 15 to 19 caused an increase in the peak pressure, density, combustion velocity, turbulence, peak temperature, NOx and a decrease in soot emissions. It can be assessed that the B20 SME is best suited to implement it into diesel engine without any effects. It has been founded from the results that 19 compression ratio has shown good performance and low emissions as compared to other compression ratios. The results obtained from the experimental investigation have been compared with the results of CFD analysis and are found to be in good agreement with each other with just slight deviation.

Experimental study of the spray, combustion, and emission performance of a diesel engine with high n-pentanol blending ratios

n-Pentanol exhibits some advantageous fuel properties, such as a higher energy density, lubricity, viscosity, and low hygroscopicity, when compared to short-chain alcohols. It is miscible with pure diesel in large proportions and burns directly on diesel engines. Therefore, n-pentanol is considered to be a promising diesel fuel additive. However, the differences between the chemical and physical properties of n-pentanol and commercial diesel affect the spray, combustion, and emissions performance of commercial diesel engines. In this study, visualization and engine experimental test methods were used to study the spray, combustion, and emissions performance of diesel/n-pentanol mixtures. The results showed that the atomization characteristics of diesel/n-pentanol mixtures were better than those of diesel. As the engine load increased, the maximum in-cylinder pressure and heat release rate increased. The brake specific fuel consumption (BSFC), nitrogen oxide (NOX), hydrocarbons (HC), and carbon monoxide (CO) emissions decreased, but soot emissions increased. Compared to diesel fuel, adding n-pentanol to pure diesel resulted in a decrease in soot emissions, while the BSFC, HC, and NOX emissions increased. Upon adding 50% n-pentanol to pure diesel (P50), the soot emissions decreased by up to 77.15% and the brake thermal efficiency (BTE) decreased by 1.86%. In summary, P50 could be burned directly on the diesel engine without any modifications, which can significantly reduce soot emissions; in this case, the BTE experienced only a slight decrease.

PENGARUH PENGGUNAAN ENERGI TERBARUKAN BUTANOL TERHADAP PENURUNAN EMISI JELAGA MESIN DIESEL INJEKSI LANGSUNG BERBAHAN BAKAR BIODIESEL CAMPURAN SOLAR DAN JATROPA

Diesel engines are widely used as driving forces in vehicles and industry due to fuel efficiency and high output power. The wide use of diesel engines triggers an increase in fuel consumption and exhaust emissions that are harmful to health. Jatropha is a renewable fuel as a solution to increase fuel consumption. However, the high viscosity and low calorific value result in reduced performance and increased exhaust emissions. Butanol has a high oxygen content and cetane number and low viscosity compared to diesel and jatropha. Addition of butanol is possible to reduce the decrease in performance and exhaust emissions of diesel engines. this study evaluates the effect of butanol on reducing Isuzu 4JB1 diesel engine direct injection emissions. Percentage of blend used 70/30/0, 65/30/5, 60/30/10, and 55/40/15 based on volume. Tests are carried out at 2500 constant turns with a loading of 25% to 100% using the EGR system. The experimental results showed the presence of butanol caused a decrease in soot emissions produced by diesel engines

Investigation on combustion and emission characteristics of a common rail diesel engine fueled with diesel/n-pentanol/methanol blends

Diesel, n-pentanol, and methanol can form stable, transparent and homogenous fuels. Combustion and emission characteristics of diesel, n-pentanol and methanol blends are investigated on a common rail diesel engine. Test fuels are noted as D100 (diesel), D80P20 (20% n-pentanol and 80% diesel, by vol.), D70P20M10 (20% n-pentanol, 10% methanol and 70% diesel, by vol.) and D70P15M15. At low and partial loads, blend fuels exhibit obviously longer ignition delays, higher peak heat release rates, shorter combustion durations and higher peak combustion temperatures than diesel. At medium and high loads, high oxygen contents result that blend fuels have higher intensities of diffusion combustion than diesel and thereby higher peak combustion temperatures. With the increase of methanol blending ratio, the ignition delay prolongs, the combustion duration shortens, and the peak combustion temperature increases. Also, the soot emissions decrease and NOx emissions increase with methanol. Retarding injection timing may decrease the NOx emissions, whereas increase the soot emissions for D100, D80P20 and D70P20M10. D70P15M15 has the lowest soot and ultrafine particles emissions and suitable retarding can simultaneously decrease the soot and NOx emissions compared to diesel in original injection timing, especially at medium and high loads.

Comparison of the Spray and the Spray/Wall Interaction of Two Gasoline Injectors

One important parameter influencing mixture formation and spray/wall interaction within engines is the geometry of the nozzle. In contrast to Diesel nozzles, the influence of the orifice geometry on spray formation has hardly be investigated for gasoline nozzles. In order to demonstrate the potential of adjusting the nozzle geometry of a modern GDI nozzle, we compare two six-hole, high-pressure nozzles with an identical structure, but different rounding radius of the orifice hole-inlet and different orifice hole-geometries: nozzle A with a rounded inlet and an orifice length to diameter ratio of 3/2 and nozzle B with a sharp inlet and an orifice length to diameter ratio of 1. In a first measurement campaign the spray formation is visualized using high-speed shadowgraphy imaging. The results show differences in spray angle and penetration depth. In a second measurement campaign we examine the spray/wall interaction and wall film formation by means of infrared thermography. The thermography measurements indicate that the geometry of nozzle B produces sprays with beneficial characteristics. This is very important for a clean combustion process and a decrease of soot emissions.

A numerical study on the effects of boot injection rate-shapes on the combustion and emissions of a kerosene-diesel fueled direct injection compression ignition engine

In this work, the effects of boot injection rate-shapes on the combustion process and emissions formation of a direct injection compression ignition engine fueled with kerosene and diesel are investigated through numerical simulations. Boot injection rate-shapes with varying boot injection velocity and boot injection duration are used. The KIVA4-CHEMKIN code is used in conjunction with a phenomenological soot model and an improved kerosene-diesel reaction mechanism to study the combustion process and emissions formation. The phenomenological soot model consists of a number of sub-models from literature that accounts for soot particle inception, soot coagulation, soot surface growth via the hydrogen-abstraction-carbon-addition (HACA) mechanism and soot surface oxidation by oxygen (O2) and hydroxyl radical (OH). It should be noted that the improved kerosene-diesel reaction mechanism is robust enough to predict the combustion and emissions trends of kerosene with respect to diesel. From this study, boot injection rate-shapes are seen to cause combustion phasing and cause lower nitrogen oxide (NO) emissions in general. Furthermore, it is observed that when kerosene replaces diesel, engine efficiency and NO emissions increase while carbon monoxide (CO) and soot emissions decrease. Soot mass quantity, soot particle number and soot particle size are the lowest for pure kerosene combustion. Finally, detailed analyses of the effects of boot injection rate-shapes on soot particle dynamics are also presented.

Modelling and optimization of exhaust pollutants and the properties and characteristics of ethanol‐diesel through a statistical approach

AbstractThis work assesses the influence of diesel additives on chemico‐physical properties (flash point, density, viscosity, and cetane number) and exhaust emissions (CO, CO2, nitrogen oxides, and soot). Experimental tests are performed in a 4‐cylinder turbocharged, common rail direct injection engine. Experiments are conducted in different percentages of ethanol (5 and 10 %) and nitrogenate additives (2 and 5 %). The current essay applies various types of tertiary additives (nitro methane, nitro ethane, and 2‐methoxy ethyl ether). All the compositions of ethanol in the diesel make the cetane index, flash point, density, and viscosity reduce. In contrast, these properties get enhanced by adding tertiary additives. Experimental studies demonstrate that nitro ethane is more effective on the decrease of soot emissions and the increase of CO, CO2, and nitrogen oxides.

The combustion and emission characteristics of a multi-swirl combustion system in a DI diesel engine

In this study, the authors developed a new multi-swirl combustion system (MSCS) and investigated its combustion and emission characteristics. The MSCS combines the structural features of a double swirl combustion system (DSCS) and a lateral swirl combustion system (LSCS) and utilizes the arc structure of the MSCS to lead fuel to (1) form multi-swirls in both a longitudinal and lateral direction, (2) accelerate the fuel/air mixture and (3) improve the combustion process in a diesel engine. An experimental study and simulation analysis was used to verify the MSCS combustion and emission characteristics. In the experimental study, tests at various speeds were conducted using a single-cylinder diesel engine. The experimental results, including the brake specific fuel consumption (BSFC), soot emission, NOx emission and in-cylinder pressure were recorded and compared with results from a DSCS that was operated under the same condition. In the simulation, the fuel spray process was studied using AVL-Fire. The fuel velocity profile and the fuel/air equivalent ratio distribution were studied to verify the formation of multi-swirling fuel in the combustion chamber. The experimental results show that the BSFC of the MSCS was lower by 4–5g/(kWh), and the soot emission was lower by about 60% in comparison to the results from the DSCS. The simulation results show that the fuel formed two longitudinal swirls in opposite directions after touching the circular ridge, and the fuel in the outer chamber formed two swirls in lateral space after touching the convex edge. This multi-swirl enlarged the diffusion space of the fuel in both the inner and outer combustion chamber and accelerated the formation of the fuel/air mixture, which led to a decrease in soot emission and fuel consumption from the MSCS.

Smoke Point Measurements of Diesel-Range Hydrocarbon–Oxygenate Blends Using a Novel Approach for Fuel Blend Selection

The use of oxygenated fuels decreases particulate matter (PM) emissions from diesel engines. Studies using engines, experimental flames, and modeling have shown that the decrease in soot emissions ...

Experimental studies on combustion and emissions of RCCI fueled with n-heptane/alcohols fuels

This paper presents an experimental study on combustion and emissions characteristics of reactivity controlled compression ignition (RCCI) combustion in which in-cylinder directly injected n-heptane combined with port injection (PI) of ethanol, n-butanol and n-amyl alcohol are used in a single-cylinder engine. The results show that when the overall lower heating values (LHVs) per-cycle is constant, with the increase of premixed ratio (RP), nitrogen oxides (NOx) and soot emissions decrease. When in high overall LHVs per-cycle, NOx and soot emissions of ethanol, n-butanol and n-amyl alcohol RCCI are also high. Meanwhile, compared to n-heptane/n-butanol and n-heptane/n-amyl alcohol, the combustion phases of ethanol RCCI are strongly delayed at high premixed ratio. For certain premixed ratios and overall LHVs per-cycle, low NOx and soot emissions can be realized when fueled with ethanol.

Combustion and emission characteristics of diesel engine fueled with diesel/biodiesel/pentanol fuel blends

Abstract Pentanol is one of the next generation biofuels that could potentially help relieve the energy crisis and environmental problems. The objective of this study is to reveal the effects of pentanol addition to diesel and biodiesel fuels in different ratios on the combustion and emission of a single-cylinder direct-injection diesel engine. The tests were conducted at a constant speed (1600 r/min) under different engine loads without exhaust gas recirculation. The indicated thermal efficiency using pentanol blends was found to be higher than that of using pure diesel for all of tested loads from 0.5 to 1.0 MPa indicated mean effective pressure at the test conditions, which is due to its higher maximum heat release rate and shorter combustion duration. An obvious decrease in soot emissions was attained with the addition of pentanol. Moreover, emissions of nitrogen oxides (NO x ) were simultaneously reduced compared with using pure diesel fuel at low to middle loads. Furthermore, diesel engine fueled with oxygenated fuel blends can reduce the carbon monoxide and unburnt total hydrocarbons emissions except for the diesel–pentanol blends at low engine load. Finally, the strategy with 40% diesel–30% biodiesel–30% pentanol showed better combustion, emission characteristics as well as economy performance among all the fuels.

Experimental and simulation investigation of the combustion characteristics and emissions using n-butanol/biodiesel dual-fuel injection on a diesel engine

The combustion and emissions of n-butanol/biodiesel dual-fuel injection were investigated on a diesel engine based on experiments and simulations. n-Butanol was injected into the intake port, while soybean biodiesel was directly injected into the cylinder. Three different premixed ratios (rp) were investigated, including 80%, 85% and 90%. The injection timings of biodiesel were adjusted to keep the 50% burn point (CA50) between 2° CA and 10° CA after top dead center for achieving stable operation. The EGR (exhaust gas recirculation) rates were changed from 35% to 45%. Results demonstrate that the same CA50 can be achieved by the early or late-injection of biodiesel. For both early- and late-injection, the auto-ignition is triggered by the biodiesel reaction. Increasing premixed ratios can retard the combustion phasing and reduce the pressure rise rate, while the indicated thermal efficiency (ITE) reduces by about 0.6% as increasing rp to 90%. The early-injection has lower NOx emissions compared to the late-injection due to lower combustion temperature. The soot emissions are comparable for both early- and late-injection. With the increase of EGR, the NOx and soot emissions decrease, while the HC (hydrocarbons) and CO (carbon monoxide) emissions increase. The ITE reduces by 1–2% as increasing EGR to 45%.