INVESTIGATION OF THE ENGINE COMBUSTION EMISSIONS AND ENGINE COMBUSTION PERFORMANCE WHEN N-BUTANOL AS

International Journal of Mechanical and Production Engineering Research and Development (IJMPERD) ISSN (P): 2249–6890; ISSN (E): 2249–8001 Vol. 10, Issue 3, Jun 2020, 951-968 © TJPRC Pvt. Ltd.

INVESTIGATION OF THE ENGINE COMBUSTION EMISSIONS AND ENGINE COMBUSTION PERFORMANCE WHEN N-BUTANOL AS ADDITIVE INTO BIODIESEL CHANGCHUN XU & HAENGMUKCHO Scholar, Department of Mechanical Engineering, Kongju National University (KNU), Budae-dong, Cheonan-si, South Korea ABSTRACT The consumption of non-renewable fuel sources (fossil fuels, etc.) in the natural environment is a large amount of exhaust gas emissions that can be generated after combustion of fuel in internal combustion engines. Due to this severe environmental problem, researchers have studied the alternative energy of engines. A new interest has emerged.

Biodiesel has been recognized as one of the most promising renewable energy sources in the world in recent decades.

Therefore, research has been conducted to increase the biodiesel-diesel mixture in which 10% n-butanol (volume) is added, which is generally considered to be an oxygen-containing additive. However, the addition of n-butanol does not engine combustion performance and exhaust emissions.

KEYWORDS: Combustion Performance, Exhaust Emissions, n-Butanol, Butanol-Acetone & Additive

Received: Apr 17, 2020; Accepted: May 08, 2020; Published: Jun 05, 2020; Paper Id.: IJMPERDJUN202084

1. INTRODUCTION

Original Article

meet engine emissions, so we can consider adding a butanol-acetone mixture as an additive to the engine to improve

Due to the current rapid population growth and serious environmental damage, in addition to the strict regulations on engine pollutant emissions, the demand for carbon neutral fuels is also high. This phenomenon has caused research scholars new interest in sustainable renewable energy [1, 8, 9]. In order to better meet the growing energy needs of all transportation, industrial and agricultural sectors and to reduce the consumption of non-renewable energy, in real life, the influence of renewable energy is indispensable[2].

In today's fast-paced world economy, the use of non-renewable energy products stored in the environment plays an indispensable role in improving the national economy and enhancing environmental development. The use of this kind of non-renewable energy poses a double challenge to everyone on the planet. This kind of non-renewable energy is not conducive to the environmental system and energy consumption. This is mainly due to the non-renewable energy characteristics of burning non-renewable energy. Elevated and caused by harmful pollutants produced after combustion [3].

Among the proposed sustainable fuels, biodiesel and alcohol blends are one of the most commonly used sustainable fuels in compression-ignition engines to reduce diesel combustion consumption and combustion exhaust emissions [18, 19]. Biodiesel is an effective and sustainable fuel. During the engine research process, the biodiesel mixture is environmentally friendly and biodegradable. It contains no heavy metal components and has excellent lubricating properties [17, 20]. However, biodiesel blends have higher viscosity and higher auto-ignition temperatures than conventional diesel. This results in a large amount of fuel consumption during the combustion process and possible

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

952

Changchun Xu & Haengmukcho

incomplete combustion of the fuel. Therefore, in order to solve or alleviate these problems and to promote the lubricating performance of the mixture fuel at a certain reasonable level during the combustion process, a high oxygen content additive such as n-butanol is usually mixed and adjusted in a small percentage [21].

Adding an ABE fuel mixture to the diesel fuel increases the thermal efficiency of the fuel and lower NOx and reduced soot emissions due to lower cetane number and higher evaporative heat storage values, lower cetane number. And, the evaporative heat storage value results in a lower cylinder temperature during combustion than pure diesel.

Sahin and Aksu [27] used n-butanol as a fuel additive in diesel engines to study in diesel engines. They studied the experimental test of adding and using 2%, 4% and 6% n-butanol diesel blend fuels with different volume ratios on diesel engines. During their experimental study, we can note that the addition of n-butanol additives to diesel engines in diesel engines produces significantly different cylinder pressure peaks and significantly different heat release rate values at all engine speed loads. A study by Jamrozik, Tutak, Pyrc, Gruca and Kocisko [57] is one of the latest studies to study the effect of diesel-butanol mixtures on engine combustion and exhaust emission characteristics.The effect of a diesel-butanol mixture on 15%, 30%, 45%, 55% and 70% n-butanol was studied using a single-cylinder four-stroke compression ignition engine with under full load conditions at specific engine speeds. Experimental results conducted showed that the thermal efficiency exhibited, the indicated average effective pressure, and the lower coefficient of change the n-butanol-diesel mixture indicative of the mean effective pressure improve engine combustion characteristics by up to 55%. However, 70% of n-butanol in diesel fuel did not show a fixed favorable mixture because it indicated a decrease in the indicated thermal efficiency, indicates the mean effective pressure and the coefficient of change in the height of the indicated average effective pressure value. The combustion effect of n-butanol-diesel blended fuel also results in lower carbon dioxide emissions and higher nitrogen oxide emissions. Lin et al. [28] Show us the experiment, which studies the effect of ABE-diesel blending on diesel engine performance and combustion performance, and fully studies the combustion state of fuel after adding additives.

The experimental results show that after the addition of the ABE mixture to the diesel fuel, the thermal efficiency can be improved and the reduction of NOx and the reduction of soot emissions are clearly indicated. During the experiment, the ABE alcohol additive was added in an amount up to 20% of the volume of the mixture. Zhao et al. [29] studied the emission of soot from the combustion of ABE mixtures with different oxygen concentrations through experiments and numerical simulations. During the testing process, research on the generation of soot in different degrees of ABE mixed combustion was proposed and implemented. The experimental results show that the soot particles are reduced under highly diluted oxygen conditions.

In this review article, we can study and explore the various properties of butanol-diesel blend fuels and compare engine combustion performance and fuel combustion exhaust emissions and analysis. The authors can show us whether the alternative fuel is suitable for a diesel engine through the combustion of a butanol diesel mixture. Second, the authors compared engine performance and combustion exhaust emissions by adding a butanol-diesel mixture to a (BA) butanol-acetone mixture or (ABE) acetone-butanol-ethanol mixture, but preparing a butanol-acetone mixture. In the final results, the authors found that the butanol mixture has a certain improvement in the performance and combustion of the diesel engine and can effectively reduce the exhaust component of the exhaust.

2. FUEL PREPARATION The main chemical properties of diesel and n-butanol are shown in Table 1. Diesel and n-butanol are injected through two sets of fuel nozzles according to volume flow, and then mixed into the engine cylinder. The volume of the two fuels is measured by a fuel volume flow meter. The values shown in the table below are used as a benchmark. For the purpose of analysis, use the equation to define the energy ratio (ψ) of the premixed fuel.

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

953

𝑚̇𝑃𝐹𝐼 。𝐿𝐻𝑉𝑃𝐹𝐼 𝑃𝐹𝐼 .𝐿𝐻𝑉𝑃𝐹𝐼 +𝑚̇𝐷𝐼 .𝐿𝐻𝑉𝐷𝐼

Ψ=𝑚̇

(1)

Where:Ψ, fuel ratio of pre-mixed fuel, 𝑚̇𝑃𝐹𝐼 butanol PFI fuel addition rate (kg/cycle), 𝑚̇𝐷𝐼 fuel DI fuel addition amount ( 9kg/cycle), LHVPFI, lower heating value of premixed butanol fuel (Kj/kg) LHVDI, lower heating value of DI fuel (kJ/kg) Table 1: Fuel Properties of Diesel and n-Butanol [60] Fuel Properties N-butanol Diesel Formula C4H90H CH1.87 Carbon content(% mass) 64.8 86.8 Hydrogen content(% mass) 13.6 13.2 Oxygen content (% mass) 21.6 0 Density @ 15℃, (kg/m3) 813 858 Boiling Temp@ 1 bar (℃) 117.5 180-350 Lower Heating Valve(MJ/kg) 33.1 42.5 Cetane Number ~25 46.5 Octane Number ~87 ~25 Viscosity @ 40 ℃ (cSt) 3.6 2.7 591 300 HFRRa WSDb (𝝁𝒎)

3. BLEND PROPERTIES N-Butanol (B) and acetone (A) are the main components used in the production of BA blend fuels [25].Compared to ethanol, butanol has many advantages. Ethanol can improve the mixture of biodiesel: it has higher cetane number, kinematic viscosity and calorific value. (1) Alcohols - Biodiesel blends: First, lower cetane numbers and higher levels of latent calorific value of alcohol evaporation can result in longer autoignition ignition delays when fuel is burned, as well as higher heat release rates, resulting in lower in-cylinder pressure and lower Cylinder temperature. Reduce the density and viscosity of the alcohols blends. Improves spray characteristics and enhances the air-fuel mixing process. Long auto-ignition ignition delays can reduce the density of the alcohol mixture and the viscosity of the mixture fuel. It can effectively improve the characteristics of the spray and enhance the air-fuel mixing process to achieve full combustion of the fuel. The full oxygen pressure in the alcohol fuel can effectively enhance the more complete combustion of the fuel in the engine cylinder, thereby improving the thermal efficiency of the fuel, and finally found that the CO, NOx and PM emissions can be effectively reduced.(2) The alcohol fuel can produce a mixture of butanol and acetone (BA) components from the biomass feedstock by a fermentation process that produces a certain proportion. However, the use of ethanol fuel in fuel as an additive to CI engines may have the disadvantage of certain fuel combustion, reducing the presence of ethanol can effectively increase the combustion efficiency of a combustion engine. However, it has been found from this study that the role of BA blend fuel as an additive to diesel fuel is to effectively enhance injection permeation, thereby promoting adequate combustion, thereby reducing exhaust emissions (including UHC, CO and NOx), as well as promote some improvements in engine braking power (BP).

4. EXPERIMENTAL SETUP AND PROCEDURE The spray characteristics at the time of fuel injection (the degree of penetration generated at the time of spraying and the angle of the taper angle generated at the time of spraying) are taken at the same injection time by taking the average value of all the values in the elapsed time, and the conditions of the injection can be expressed as the spray characteristics of the fuel injection. The result is shown in Figure 1. The average of the values of the six jet injections per test was further tested by three devices [37]. We can assume that the shape of the spray when the fuel is injected is a cone, and the end of the injection can be imagined as a hemisphere, so the amount of spray can be calculated by the mathematical equation [37].

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

954

Changchun Xu & Haengmukcho

V=(

𝜋 3

𝜃 2 𝜃 [1+𝑡𝑎𝑛( )]3 2

)𝑆 3 [𝑡𝑎𝑛2(θ)]

1+𝑡𝑎𝑛( )

(2)[37]

Figure 1: Jet Injection State [25].

Figure 2: Cylinder Pressure and Heat Release Rate of n-Butanol HCCI Under Different Intake Conditions [59].

Auto-ignition is driven by the unique chemical kinetics of the fuel in the cylinder, and the rate of combustion is jointly controlled by the thermodynamic conditions within the cylinder and the chemical nature of the fuel of the reaction mixture [38]. In a diesel engine, the reaction mixture fuel must be combusted with a small amount of residual fuel remaining from the previous combustion reaction and a product formed after combustion.Shui Yu et al. [59] A number of studies were conducted, mainly for experiments involving the combustion of n-butanol and diesel mixed fuels in HCCI engines. The experimental results found and demonstrated that the simultaneous generation of NOx and soot emissions can be effectively reduced to ultra-low levels. Because n-butanol contains a certain amount of oxygen atoms and a small amount of cetane number, in the HCCI combustion emission mode, the combustion of n-butanol promotes a sufficient chemical reaction between the oxygen atoms contained in the alcohol and the fuel. The low cetane number effectively promotes the prolongation of the combustion process, reduces the increase in temperature during the combustion process, prolongs the ignition point time, and suppresses the generation of NOx and soot emissions. In order to more effectively prove the controllability of the combustion process and the phasing reaction of n-butanol HCCI, a set of experimental results are extracted from a large number of existing databases as shown in Figure 2 below. Under the condition of constant injection volume of n-butanol PFI, the effects of intake air temperature, supercharging, and engine EGR were studied. After adjusting the variables to be controlled, keep the other two variables at a certain value, so as to avoid compound effects. At a certain fueling rate, heating the gas entering the cylinder can further lead to an earlier combustion stage and an earlier and more

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

955

stable combustion process.

The most important benefit of adding specific n-butanol as a fuel additive to the engine cylinder for combustion is that, it can achieve an ultra-low NOx generation rate and emit smoke after the fuel is burned. However, after the combustion of n-butanol injected fuel, the interior of the HCCI engine is highly sensitive to the entry conditions caused by intake air. Therefore, the pilot injection strategy in the engine cylinder is widely considered to be feasible for improving the fuel's combustion controllability. During this refueling process, most of the fuel energy is still pre-mixed with n-butanol as the primary condition, but the conditions of ignition before combustion and fuel combustion are mainly controlled by the pilot injection fuel conditions of the engine DI.

Figure 3: The Different EGR Rates Affect Engine Performance [61].

Liu et al. [61] studied the n-butanol dual fuel injection on diesel engines. The results of the study indicate that different EGR rates affect not only exhaust gas generation and emissions, but also performance of engine. As shown in Figure 3 below, the results of the study indicate that there are differences in ignition delay and fuel combustion duration caused by different EGR rates and injection timings in the experiment. Under different fuel injection conditions, different EGR rates will have different effects on engine exhaust. However, under the early injection conditions, different EGR rates have a small effect on ignition delay, but the EGR rate has a greater effect on ignition delay under late injection conditions.

As the exhaust gas entering the cylinder gradually increases, the higher EGR rate causes longer ignition delay. As the EGR rate continues to increase, the combustion reaction rate decreases and the combustion duration increases. Increasing the EGR rate causes the combustion temperature to decrease, so part of the fuel cannot be fully oxidized. On the one hand, reduced combustion efficiency leads to a reduction in ITE. On the other hand, the prolongation of the combustion duration is due to the higher EGR rate, which reduces the temperature of combustion during constant volume. For some of the reasons mentioned above, it is possible to reduce the emission of nitrogen oxides in the exhaust gas.

The ignition delay value can be represented by the crank angle value, because it defines the distance between the fuel from the initial process of the injection and the initial process of the fuel combustion phenomenon to the development process.The correlation of various characteristics between diesel and butanol fuel is crucial, because the volume ratio in the mixed fuel increases with the increase of butanol fuel as an additive,the ignition delay of the blended fuel is longer (butanol contains lower cetane number, with butanol volume ratio) the increase has led to a gradual decrease in the cetane number of the blended fuel. On the other hand, the increase in the ignition delay of the fuel can be attributed to the higher vaporization and heat storage contained in the fuel itself, which requires higher temperatures and longer periods of time, which causes the ignition delay of the combustion.

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

956

Changchun Xu & Haengmukcho

Because of the performance of different bio-fuels, have different ignition delay times, as shown in figure 4.

During engine combustion, the ignition delay of the mixture fuel is higher, and the vaporization process requires more time and more heat due to higher vaporization heat storage, and because ethanol contains a lower cetane number, it leads to high ignition delay and 5-10 times lower than diesel fuel and biodiesel. Therefore, combustion of the mixture fuel requires higher pressure and temperature levels to ignite the air-fuel mixture. As the engine cylinder temperature gradually increases, the ignition delay time is gradually reduced as the engine load increases. Increasing the butanol content in a particular fuel also increases the latent heat of vaporization of the fuel mixture and causes the volatility of the mixture fuel to decrease due to the cetane number in the mixture fuel and the formation of several ignition centers in the combustion chamber. Effectively reduces overall mixing and reaction time and then reduces burn duration.

Some factors inside the engine, such as ignition delay and combustion duration, are closely related to SOI. From the results of the study, we can see some subtle changes. As the SOI time changes, the ignition delay of each fuel changes, but the changes are small and there is no large change. But when the SOI approaches TDC, the combustion time there will be a noticeable shortening. Moreover, since the octane number and latent heat value of PFI fuel effectively determine the ignition delay and the subsequent duration of combustion, this phenomenon has the largest impact on the indicated thermal efficiency. Since PFI fuel will lead to better premixing of the fuel and result in better combustion with the mixed fuel, the study of the combustion duration of RCCI combustion has obtained a better result than the combustion of DI biodiesel engines The duration is short, so in the early period of SOI, the indicated thermal efficiency of RCCI is higher than that of single injection of biodiesel. Regarding the delayed injection time, pure biodiesel shows a higher indicated thermal efficiency, which is mainly due to the lower HC and CO emissions generated in the tail gas emission process, resulting in higher combustion efficiency. Zheng et al. [60] studied the effect of different SOI on the emissions of using three biodiesel fuel mixtures. The results show that RCCI combustion produces less soot emissions than pure biodiesel DI. As the combustion temperature in the cylinder is reduced, all soot emissions increase as the SOI decreases. Therefore, it can be considered that the reduction of SOI weakens the oxidation reaction of soot. Figure 4 shows the comparison of ignition delay and combustion duration between three RCCI combustion modes as the SOI changes.

Figure 4: Ignition Delay and Combustion for Different SOI [60].

"Combustion duration" refers to the duration of fuel combustion when used at an angle of 10% to 90% relative to the crank angle. However, with the same power, the engine needs a large or even greater fuel combustion demand to maintain the same engine load as the diesel engine, thus causing more fuel demand and a longer combustion duration.[51].

Due to the mixed fuel mode, n-butanol and diesel have different cetane numbers, so the added n-butanol is used as an additive to mix with diesel. After mixing, the cetane number of the mixed fuel will decrease. This result means that, the Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

957

ignition ability of the fuel is suppressed to a certain extent, so the ignition delay of the mixed mode shows a gradual increase trend with respect to the increase of the n-butanol ratio. The increase in the mixing ratio of n-butanol means a longer ignition delay, which effectively promotes the extension of the air-fuel mixing process and promotes fuel mixing, thereby reducing the combustion duration of the fuel and increasing the combustion ratio during premixing, thereby As a result, the combustion time of the hybrid mode becomes shorter, which leads to a shorter energy release time of the fuel in the DI engine, reducing heat transfer loss and increasing the isometric value. Under low load, the combustion duration caused by the difference in the injection ratio of n-butanol in the RCCI engine is different from that of medium load and high load, because at low load, the temperature in the cylinder is lower and the reactivity between the fuel After the injection of PFI n-butanol, the reactivity of the in-cylinder temperature and fuel will be further reduced, and the reaction rate of the fuel will be inhibited, resulting in longer combustion duration and lower MPRR. In the medium and high load PFI n-butanol injection process, due to the change in the fuel injection amount, the ignition delay is almost unchanged, and the combustion characteristics when the n-butanol ratio is changed will not change much. Because with the increase of the amount of PFI n-butanol injection, the content of n-butanol injection reaches a certain peak, with the large amount of n-butanol injection, the cetane number of the mixed fuel can be improved, which causes the ignition delay time to change. Short and sharply reduced burning duration. On the other hand, the reason is that the high PFI injection ratio will increase the injection concentration of n-butanol in the cylinder, making the fuel easier to ignite by compression. In this way, DI biodiesel will be injected with a high concentration of n-butanol by compression, and the results show a high preheat curve and a maximum heat release rate.

Figure 5 shows the ignition delay and combustion duration (during low load) with different premixed mass fractions.

[63] It can be observed from the figure 6 that as the n-butanol mass fraction increases, the in-cylinder temperature and local air / fuel ratio decrease, resulting in poor atomization. Following the injection of diesel, the ignition delay increased from 1.2 degrees CA and 6.7 degrees CA. As the mass of n-butanol injected at the port increased from 43% to 71%, the burning duration decreased by 7.6CA. This is because during the low temperature reaction, n-butanol will form more free radicals as the temperature increases, so in the subsequent high temperature reaction in the cylinder, n-butanol will cause faster burning a large number of free radicals due to the longer ignition delay in the previous low temperature reaction.

Figure 5: Effect of Premixed Mass Percentage on Combustion Duration [63][64].

5. IN-CYLINDER PRESSURE AND HEAT RELEASE RATE Diesel fuel has a high in-cylinder pressure peak, while the pressure peak in the cylinder of biodiesel blend fuel is 12% lower than the in-cylinder pressure peak of pure diesel. Mainly because the high fuel viscosity reduces the effective mixing rate of air and fuel. Therefore, the in-cylinder pressure peak of biodiesel and its mixture is lower than the in-cylinder pressure peak

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

958

Changchun Xu & Haengmukcho

of diesel. When an additive such as an alcohol is added to the mixture, since the alcohol contains a lower combustion viscosity, as the percentage of the alcohol increases, the fuel viscosity of the biodiesel mixture is reduced, and the mixing rate of air and fuel is increased.

Figure 6: Display of Cylinder Pressure and HRR for Biodiesel Blends at Specific Engine Speeds[25].

As can be seen from Figure 6, the peak in-cylinder pressure produced by the mixture with biodiesel-butanol is higher than the peak in-cylinder pressure produced by pure diesel. Corresponding to the pressure of its high peak cylinder, the mixture shows the highest peak HRR of all tested fuels[25].

The maximum rate of heat release from the fuel within the engine depends on the time of ignition delay in the fuel, the amount of fuel involved in the premixed combustion process, and the air-fuel mixture fuel mixing process and the formation of the mixture fuel. Since the ignition delay time of the fuel is relatively short, the viscosity of the fuel is high and the calorific value is low, and the maximum release heat rate of the biodiesel is lower than the maximum release heat rate at the full load of the diesel. And, the biodiesel-n-butanol blend fuel exhibits a lower maximum heat release rate than biodiesel fuel and diesel under full engine load conditions. Because butanol fuels contain lower viscosities and higher calorific values as well as high heat of latent heat of vaporization. However, the latent heat of vaporization of the fuel and the energy content of the blend determine the rate of heat release.

The peak cylinder pressure of a diesel natural compression engine is primarily determined by the ignition delay time of the fuel, the preparation of the air-fuel mixture fuel, and the heat released by combustion after thorough mixing during the premixed combustion stage. The peak pressure of all tested fuels increases as the load increases. This trend is due to an increase in the amount of fuel injected at higher loads and an increase in cylinder temperature. By adding the volume ratio of butanol to the mixture, the peak cylinder pressure is increased compared to the biodiesel throughout the engine operation.

More heat is released during the premixed combustion phase due to an increase in ignition delay (containing a lower cetane number) and more oxygen available in the fuel mixture.

5. BRAKE SPECIFIC FUEL CONSUMPTION (BSFC) AND BRAKE THERMAL EFFICIENCY (BTE)

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

959

Figure 7: Analysis and Comparison of BSFC under Different Fuels at Different Engine Speeds [33].

It can be seen from figure 7that as the amount of BA added increases, the calorific value of BA-diesel decreases by 6.5% at 30 BA, which significantly affects BSFC [33]. Similar results have been reported in current and previous studies that have affected the effects of higher ratios of oxygenates, which support higher concentrations of oxygenates in fuel mixtures that reduce calorific value and lead to increased fuel consumption. [54]. Therefore, such mixed fuel combustion requires more fuel to match the original power of the diesel.

The BA-diesel fuel mixture increases the BSFC, and since the oxygen content of the BA fuel mixture is relatively high, a higher BTE release is achieved as the BA fuel content increases. As the oxygen content in the alcohol fuel mixture increases as the BA fuel increases, an increase in BTE is achieved. High levels of oxygen help to increase the fuel's combustion efficiency, especially during the diffusion combustion phase of the engine shown in Figure 8.Another factor influencing BTE is the cetane number. The BA-diesel fuel mixture contains a cetane number lower than the cetane number contained in the diesel fuel. For this reason, the fuel has a longer ignition delay during spontaneous combustion, which allows the air and fuel in the cylinder to be sufficiently mixed, thus allowing a wider range of fuels to be burned in the premix mode.

In addition, the burning rate of the fuel is an important aspect related to the thermal efficiency of the brake. Larger chains of alcohols such as butanol have a higher flame burning rate. Therefore, a higher proportion of butanol contents in the BA mixture are responsible for the higher BTE.

Figure 8: Comparison and Analysis of BTE at Different BA Ratios at Different Engine Speeds [33],[64].

The braking thermal efficiency mainly depends on the calorific value contained in the fuel itself and the fuel consumption during combustion. Figure 8 shows the difference in braking thermal efficiency and equivalent ratio for different fumigation percentages under different load conditions. For the lowest torque produced during engine operation, the

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

960

Changchun Xu & Haengmukcho

conversion efficiency of fuel combustion increases as the butanol content increases, as the process of evaporation can be found to be significantly more effective when less mixture fuel is injected into the engine cylinders.

6. ENGINE EMISSIONS NOx Emissions The two important factors that affect the formation of NOx are the oxygen content and the maximum temperature generated by combustion in the cylinder. There are other necessary factors such as: cylinder geometry, compression ratio, cylinder pressure, intake air temperature and chemical properties. Figure 9 shows the amount of NOx formation at various equivalent ratios for different equivalent ratios. The results show that the formation of nitrogen oxides can be reduced to 20% with the increase of the amount of n-butanol injected. When n-butanol is injected, the mixture of n-butanol and diesel will reduce the fuel’s cetane number, and while increasing the cylinder fuel’s oxygen content when fuel burned, the combustion enthalpy changes little. Increasing the oxygen content has resulted in a higher ratio of air when fuel spray into cylidner, which affects the decrease of the cetane number and increases the enthalpy of evaporation, thereby generating a certain cooling effect during the mixing process of the mixture and reducing the formation of NOx.

Figure 9: Analysis of NOx Emissions with Different BA Ratios at Different Engine Speeds[64] [33].

BA-diesel fuel is mixed with NOx emissions, and engine speed varies with engine speed, as shown in figure 9. It can be seen from the figure that as the speed increases, the NOx emission decreases, and the lower the cetane number of the mixture, the higher the heat of vaporization. This gasification endothermic causes the temperature in the cylinder to decrease.

As the percentage of butanol increases, the NOx emissions are reduced.

Unburnt Hydrocarbon (UHC) Emissions Incomplete combustion of hydrocarbon emissions is due to exhaust emissions of fuel in the engine after combustion, however due to incomplete combustion of the fuel in the engine's combustion chamber due to various chemical and physical properties. When the engine is operated under too lean air-fuel mixture conditions, the total amount of HC engine exhaust emissions may also increase, resulting in the diluted state, slow combustion during flame propagation during and after ignition of the fuel and air in the cylinder.

The mixture of n-butanol and biodiesel improves engine performance and significantly reduces emissions (except UHC) due to reduced viscosity and the presence of more oxygen in the blend compared to pure biodiesel. UHC emissions are higher than diesel emissions, while NO, CO and smoke emissions are reduced. The biodiesel-butanol mixture has lower fuel consumption than diesel fuel, because it has better and more complete combustion.

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

961

Figure 10: UHC Emission Analysis between Different BA Mixing Ratios and Different Engine Speeds[33][60].

As can be seen from Figure 10, for the mixing ratios of different degrees of BA fuel mixture in diesel engines, the unburned hydrocarbon content in the exhaust gases produced at different engine speeds is analyzed. The graph shows that the addition of butanol to diesel fuel increases UHC. With the HC emissions of the three engine load conditions, it is found that as the load in the figure increases, it shows a downward trend under different PFI ratios. This is because the order of RCCI HC using different PFI fuels under the same load is different. When the PFI ratio is 50%, the ignition delay of different RCCI combustion is almost the same, and no significant change will occur due to the low oxygen content of DMF. The content leads to higher emissions of HC. However, when the PFI is 80%, HC emissions and ignition delay occur at the same time.

The appearance of this result means that RCCI engines with longer ignition delays will always exhibit higher HC emissions.

Carbon monoxide (CO) Emissions Carbon monoxide (CO) is one of the important components of pollutants in the atmospheric climate system. It is a harmful substance. Because it has serious health effects on humans and animals at high concentrations, it reduces the environmental protection of carbon monoxide emissions plays a vital role [46]. Therefore, the most likely reason for increasing carbon monoxide emissions is the incomplete combustion reaction between fuel and air. Butanol is an oxygenated alcohol, so the addition of butanol will increase the oxygen content. Therefore, the oxygen content based on the molecular weight of butanol can improve the combustion efficiency, resulting in more complete combustion. The use of pure biodiesel blend fuels produces lower CO emissions than pure diesel fuels, but further increases CO emissions by adding BA blend fuel as an additive to the engine. Because these fuels are compared to pure diesel, the BA mixture fuel and the biodiesel mixture have higher oxygen content and lower hydrocarbon content, which can reduce CO emissions[47].

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

962

Changchun Xu & Haengmukcho

Figure 11: Analysis of Exhaust CO Emissions between Different BA Mixing Ratios and Engine Speeds[60] [66].

Figure 11shows as a result of the complete combustion of the high oxygen content in the BA blended fuel, the CO emissions of the BA-diesel blend fuel are significantly reduced compared to conventional diesel fuel.The BA-diesel fuel mixture contains a relatively high oxygen content, and the higher oxygen content can effectively promote the CO oxidation reaction and promote complete combustion, thereby significantly reducing CO emissions [56].

In the RCCI engine, the CO emissions are somewhat similar to the HC emissions of the same load trend. Compared with the hybrid mode, the CO and HC emissions in the exhaust are higher. This is mainly because in the RCCI mode, n-butanol is introduced into the cylinder through the air inlet port injection, and the highly premixed fuel is evenly distributed in the cylinder near the cylinder wall, including the gap region and the boundary layer region, resulting in almost it is not completely oxidized, so CO and HC emissions are high. Another reason is due to insufficient oxygen levels. During the low-temperature combustion process, fewer oxygen molecules will react with carbon molecules.

7. CONCLUSIONS In this review paper survey, we conducted an analysis to evaluate the combustion of biodiesel-n-butanol mixtures on diesel engines, exhaust emissions and engine performance characteristics to assess engine combustion and performance and Parameters of exhaust emissions. [48]. and made a variety of percentage mixing tests and analysis.

The brake thermal efficiency is increased to add biodiesel to the fuel mixture and is smaller than diesel for mixtures with n-butanol. The discovery that biodiesel in the mixture reduces carbon monoxide emissions and NOx, and the addition of n-butanol reduces tail gas. Butanol in the mixture increases due to an increase in oxygen supply due to the addition of butanol.

Mixtures with biodiesel can be found to reduce hydrocarbon emissions, but with the addition of n-butanol, hydrocarbons will increase. The duration of combustion increases as the load increases. As the butanol content value in the mixture fuel increases in volume percentage, the ignition delay time gradually increases, resulting in a gradual decrease in the combustion duration. The value of the oxygen pressure in the butanol determines the length of the ignition delay time, which has a significant effect on the EGT, because the content of butanol in the mixture fuel increases with the volume percentage, causing an increase in the oxygen content of the mixture fuel. Thus, as the value of the butanol content in the blend fuel increases, an increase in the EGT value is caused.

During the study of combustion emissions from internal combustion engines, as the EGR rate increased, the temperature in the cylinder was lower, which resulted in a reduction in NOx emissions. Because of the low temperature, the decrease in the reaction rate led to increased HC and CO emissions. ITE is reduced by increasing the EGR rate. By controlling the combustion duration period and the EGR rate, it is possible to achieve a relatively low NOx emission inside the engine after combustion.

ACKNOWLEDGMENT This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2019R1A2C1010557).

REFERENCES 1.

Algayyim SJM, Wandel AP, Yusaf T, Hamawand I. Production and application of ABE as a biofuel, Renew Sustain Energy Rev 2018;82(Part 1): 1195-214.

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel 2.

963

Algayyim SJM, Wandel AP, Yusaf T, Hamawand I, Al-Lwayzy S. Experimental study of spray characteristics, engine performance and emission levels of acetone-butanol-ethanol mixture-diesel blends in a diesel engine. 11th Aisa-Pacific Conference on Combustion, NSW Australian: The University of Sydney; 2017.10th-14th December.

3.

A. Gupta, J.P. Verma, Sustainable bio-ethanol production from agro-residues: A review, Renewable and Sustainable Energy Reviews, 41(2015) 550-567.

4.

H. Huang, Z. Li, W. Teng, R. Huang, Q. Liu, Y. Wang, Effect of EGR rates on combustion and emission characteristics in a diesel engine with n-butanol/ PODE3-4/diesel blends, Applied Thermal Engineering, 146 (2019) 212-222.

5.

T. A. Nguyen, Y. Maeda, K. Kuroda, K.Otsuka, Inclusive impact assessment for the sustainability of vegetable oil-based biodiesel-Part Ⅱ: Sustainability assessment of inedible vegetable oil-based biodiesel in Ha Long Bay, Vietnam, Journal of Cleaner Production, 168(2017) 173-188.

6.

Y. Van Fan, S. Perry, J. J. Klemes, C.T. Lee, A review on air emissions assessment: Transportation, Journal of Cleaner Production, 194(2018) 673-684.

7.

A. Atmanli, N.Yilmaz, A comparative analysis of n-butanol/diesel and 1-pentanol/diesel blends in a compression ignition engine, Fuel, 234(2018) 161-169.

8.

A. Gupta, J. P. Verma, Sustainable bio-ethanol production from agro-residues: a review, Renewable and Sustainable Energy Reviews,41 (2015) 550-567.

9.

G. Khoobbakht, M. Karimi, K. Kheiralipour, Effect of biodiesel-ethanol-diesel blends on the performance indicators of a diesel engine: A study by response surface modeling, Applied Thermal Engineering, 148(2019)1385-1394.

10. N. Yilmaz, A. Atmanli, Experimental evaluation of a diesel engine running on the blends of diesel and pentanol as a next generation higher alcohol, Fuel, 210(2017) 75-82.

11. L.E. Hombach, L.Dore, K. Heidgen, H. Maas, T.J. Wallington,G. Walther, Economic and environmental assessment of current(2015)and future(2030) use of E-fuels in light-duty vehicles in Germany, Journal of Cleaner Production,(2018).

12. W. Lv. Y. Hu, E. Li, H. Liu, H. Pan, S. Ji, T. Hayat, A.Alsaedi, B. Ahmad, Evaluation of vehicle emission in Yunnan province from 2003 to 2015, Journal of Cleaner Production, (2018).

13. Algayyim SJM, Wandel AP, Yusaf T. Experimental and numerical investigation of spray characteristics of butanol-diesel blends.

11th Asia-Pacific Conference on Combustion. NSW Australia: The University of Sydney; 2017. 10th-14th December.

14. Atmanli A, Ileri E, Yuksel B, Yilmaz N. Extensive analyses of diesel-vegetable oil-n-butanol ternary blends in a diesel engine.

Appl Energy 2015; 145: 155-62.

15. Kandasamy M, Hamawand I, Bowtell I, Seneweera S, Chakrabarty S, Yusaf T, et al. Investigation of ethanol production potential from lignocellulosic material without enzymatic hydrolysis using the ultrasound technique. Energies 2017; 10(1):62.

16. Ileri E. Experimental investigation of the effect of diesel-cotton oil-n-butanol ternary blends on phase stability, engine performance and exhaust emission parameters in a diesel engine. Fuel 2013; 09:503-11.

17. Hymavathi, D., G. Prabhakar, and B. B. Sarath. "Biodiesel production from vegetable oils: an optimization process." Int J Chem Petrochem Technol, 4 (2), 21 30 (2014).

18. M.M. Hasan and M. M. Rahman, Performance and emission characteristics of biodiesel –diesel blend and environmental and economic impacts of biodiesel production: Arevies, Renew. Sustain. Energy Rev., vol.74, no. February, pp. 938-948, 2017. www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

964

Changchun Xu & Haengmukcho 19. Shivaji, Kailash B. Anwar, and S. Gowreesh. "Experimental Investigation on Use of Preheated Pongamia Oil Bio-Diesel in DI Diesel Engine." International Journal of Automobile Engineering Research and Development (IJAuERD) 4.6 (2014): 1-6.

20. A. E. Atabani and A.D.S. Cesar, Calophyllum inophyllum L.- A prospective non- edible biodiesel feedstock. Study of biodiesel production, properties, fatty acid composition, blending and engine performance.Renew. Sustain. Energy Rev., vol. 37, pp.644-655, 2014.

21. R. Piloto-Rodriguez, Y. Sanchez-Borroto, E. A. Melo-Espinosa, and S. Verhelst, Assessment of diesel engine performance when fueled with biodiesel from algae and microalgae: An overview. Renew. Sustain. Energy Rev., vol 69, no. January 2016, pp.

833-842, 2017.

22. B. Bankovic-Ilic, O. S. Stamenkovic, and V. B. Veljkovic, Biodiesel production from non-edible plant oils, Renew, Sustain. Energy Rev., vol.16, no. 6, pp. 3621-3647, 2012.

23. S. Imtenan, H. H. Masjuki, M. Varman, I. M. Rizwanul Fattah, H. Sajjad, and M. I. Arbab, Effect of n-butanol and diethyl ether as oxygenated additives on combustion-emission-performance characteristics of a multiple cylinder diesel engine fuelled with diesel- jatropha biodiesel blend, Energy Convers. Manag., vol 94, pp. 84-94, 2015.

24. W. R. da S. Trindade and R. G. dos Santos, Review om the characteristics of butanol, its production and use as fuel in internal combustion engines, Renew. Sustain. Energy Rev., vol.69, no. October 2015, pp. 642-651, 2017.

25. S. Lee, S. Oh, Y. Choi, and K. Kang, Performance and emission characteristics of a CI engine operated with n-butanol blended DME fuel, Appl. Therm. Eng., vol. 31, no. 11-12, pp.1929-1935, 2011.

26. N. Yilmaz and S. M. Davis, Polycyclic aromatic hydrocarbon(PAH) formation in a diesel engine fueled with diesel, biodiesel and biodiesel/n-butanol blends, Fuel, vol. 181, pp.729-740, 2016.

27. Sattar Jabbar Murad Algayyim, Andrew P. Wandel, Talal Yusaf, Saddam Al-Lwayzy, Butanol-acetone mixture blended with cottonseed biodiesel: Spray characteristics evolution, combustion characteristics, engine performance and emission, Proceedings of the Combustion Institute 37(2019) 4729-4739 28. Y. Ni, Z. Sun, Recent progress on industrial fermentative production of acetone-butanol-ethanol by Clostridium acetobutylicum in China. Applied Microbiology and Biotechnology, June 2009, 83:415.

29. Z. Sahin, O. N. Aksu. Experimental investigation of the effects of using low ratio n-butanol/diesel fuel blends on engine performance and exhaust emissions in a turbocharged DI diesel engine, Renewable Energy, 77(2015)279-290.

30. Lin Y, Lee T, Nithyanandan K, Zhang J, Li Y, Lee C-F. Experimental investigation and analysis of combustion process in a diesel engine fueled with acetone-butnaol-ethanol/diesel blends. SAE International; 2016.

31. Zhao Z, Xu Z, Liu J, Wang M, Lee C-F, Chang W, Hou J. Experimental and numerical investigation of soot mechanism of acetone-butanol-ethanol(ABE) with various oxygen concentrations. SAE Int. J Engines 2015:1 32. X. Li, Z.-G. Li, Z.-P. Shi, Bioresour. Bioprocess. 1 (1) (2014) 1-13.

33. Ma X, Zhang F, Han K, Yang B, Song G. Evaporation characteristics of acetone-butanol-ethanol and diesel blends droplets at high ambient temperatures. Fuel 2015; 160:43-9.

34. Li Y, Meng L, Nithyanandan K, Lee TH, Lin Y, Lee C-FF, et al. Combustion, performance and emissions characteristics of a spark-ignition engine fueled with isopropanol-n-butanol-ethanol and gasoline blends. Fuel 2016; 184:864-72.

35. Sattar Jabbar Murad Algayyim, Andrew P. Wandel, Talal Yusaf, Saddam Al-Lwayzy, Ihsan Hamawand. Impact of

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

965

butanol-acetone mixture as a fuel additive on diesel engine performance and emissions. Fuel 227 (2018) 118-126.

36. D.C.K. Rao, S. Karmakar, S.K. Som,Combust. Sci. Technol. 189 (2017) 1–17.

37. Chong CT, Hochgreb S. Measurements of laminar flame speeds of liquid fuels: Jet-A1, diesel. Palm methyl esters and blends using particle imaging velocimetry (PIV). Proc. Combust. Inst. 2011; 33(1); 979-86.

38. Florian Pradelle, Sergio Leal Braga, Ana Rosa Fonseca de Aguiar Martins, Franck Turkovics, Renata Nohra Chaar Pradelle.

Performance and combustion characteristics of a compression ignition engine running on diesel-biodiesel-ethanol (DBE) blends-Potential as diesel fuel substitute on an Euro III engine. Renewable Energy 136 (2019) 586-598.

39. S.J.M. Algayyim, A.P. Wandel, T. Yusaf, Ener-gies,11(5) 1298–1310.

40. Zhongyuan Chen, Peng Zhang, Yi Yang, Michael J Brear, Xin He, Zhi Wang. Impact of nitric oxide (NO) on n-heptane autoignition in a rapid compression machine, combustion and Flame 186(2017)94-104.

41. Hatim Machrafi, Philippe Guibert and Simeon Cavadias, HCCI Engine Modeling and Experimental Inverstigations-Part 2: The Composition of a NO-PRF Interaction Mechanism and the Influence of NO in EGR on Auto-Ignition, Combustion Science and Technology, volume 180, 2008-Issue 7 Pages 1245-1262.

42. Zunqing Zheng, Mingtao Xia, Haifeng Liu, Ran Shang, Guixiang Ma, Mingfa Yao. Experimental study on combustion and emission of n-butanol/biodiesel under both blended fuel mode and dual fuel RCCI mode. Fuel 226(2018)240-251.

43. Xin Wang, Haifeng Liu, Zunqing Zheng, Mingfa Yao. Development of a reduced n-butanol/biodiesel mechanism for a dual fuel engine. Fuel 157(2015) 87-96.

44. Souzhu Pan, Xin Li, Weiqiang Han, Yaxing Huang. An experimental investigation on multi-cylinder RCCI engine fueled with 2-butanol/diesel. Energy Conversion and Management 154(2017) 92-101.

45. Mohamed Nour, Ali M.A. Attia, Sameh A. Nada. Combustion, performance and emission analysis of diesel engine fuelled by higher alcohols (butanol, octanol and heptanol)/ diesel blends. Energy Conversion and Management 185(2019)313-329.

46. Rao, P. Venkateswara, and BV Appa Rao. "Heat release rate, performance and vibration analysis of diesel engine operating with biodiesel-Triacetin additive blend fuels." International Journal of Automobile Engineering Research and Development 8.2 (2018): 1-12.

47. Yu Zhang, Ronghua Huang, Yuhan Huang, Sheng Huang, Pei Zhou, Xi Chen, Tian Qin. Experiment study on combustion characteristics of an n-butanol-biodiesel droplet. Energy 160 (2018) 490-499.

48. Pali Rosha, Saroj Kumar Mohapatra, Sunil Kumar Mahla, HaengMuk Cho, Bhupendra Singh Chauhan, Amit Dhir. Effect of compression ratio on combustion, performance, and emission characteristics of compression ignition engine fueled with palm (B20) biodiesel blend. Energy 178 (2019)676-684.

49. Valentin Soloiu, Jose D. Moncada, Remi Gaubert, Martin Muinos, Spencer Harp, Marcel Ilie, Andrew Zdanowicz, Gustavo Molina. LTC (low-temperature combustion) analysis of PCCI (premixed charge compression ignition) with n-butanol and cotton seed biodiesel versus combustion and emissions characteristics of their binary mixtures. Renewable Energy 123(2018)323-333.

50. Anca Madalina Dumitrescu, Ionut Banu, Gheorghe Bumbac. Process modeling and simulation for butanol removing from fermentation broth by extraction with biodiesel. Renewable Energy 131(2019) 137-143.

51. Abhijeet Killol, Niklesh Reddy, Santosh Paruvada, S. Murugan. Experimental studies of a diesel engine run on biodiesel n-butanol blends. Renewable Energy 135(2019)687-700. www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org

966

Changchun Xu & Haengmukcho 52. Geetesh Goga, Bhupendra Singh Chauhan, Sunil Kumar Mahla, HaengMuk Cho. Performance and emission characteristics of diesel engine fueled with rice bran biodiesel and n-butanol. Energy Reports 5(2019) 78-83.

53. Ahmed I. EL-Seesy, Hamdy Hassan and Hidenori Kosaka. Improving the Performance of a Diesel Engine Operated with Jojoba Biodiesel-Diesel-n-Butanol Ternary Blends. Energy Procedia156 (2019)33-37.

54. Krishna, MVS Murali, and K. Vamsi Krishna. "Studies on Exhaust Emissions of Di Diesel Engine with Low Grade LHR Combustion Chamber Fuelled with Linseed Biodiesel." International Journal of Mechanical Engineering (IJME) 3.6 (2013): 63-72.

55. M. Yusri, Rizalman Mamat, M.K. Akasyah, M.F. Jamlos, A.F. Yusop. Evaluation of engine combustion and exhaust emissions characteristics using diesel/butanol blended fuel. Applied Thermal Engineering (2019).

56. Awad, R. Mamat, T.K. Ibrahim, F.Y.Hagos, M.Noor, I. Yusri, A. Leman, Calorific value enhancement of fuels oil by moisture removal and its effect on the performance and combustion of a spark ignition engine, Energy Conversion and Management, 137 (2017) 86-96.

57. P.M. Merker, C.Schwartz, G.Stiesh, F. Otto, Simulating Combustion- Simulation of Combustion and pollutant Formation for Engine-Development, Springer, 2006.

58. Siwale L, Kristof L, Adam T, Bereczky A, Mbarawa M, Penninger A, et al. Combustion and emission characteristics of n-butanol/diesel fuel blend in a turbocharged compression ignition engine. Fuel 2013; 107:406-18.

59. Rakopoulos DC, Rakopoulos CD, Papagiannakis RG, Kyritsis DC. Combustion heat release analysis of ethanol or n-butanol diesel fuel blends in heavy-duty DI diesel engine. Fuel 2011; 90(5):1855-67.

60. Rakopoulos DC, Rakopoulos CD, Giakoumis EG, Dimaratos AM, Kyritsis DC, Effects of butanol-diesel fuel blends on the performance and emissions of a high-speed DI diesel engine. Energy Convers Manage 2010; 51(10): 1989-97.

61. A. Jamrozik, W. Tutak, M. Pyrc, M. Gruca, M. Kocisko, Study on co-combustion of diesel fuel with oxygenated alcohols in a compression ignition dual-fuel engine, Fuel, 221(2018) 329-345.

62. S. Gurgen, B. Unver, I. Altrn, Prediction of cyclic variability in a diesel engine fueled with n-butanol and diesel fuel blends using artificial neural network, Renewable Energy,117(2018) 538-544.

63. Shui Yu, Liguang Li, Ming Zheng. n-Butanol reactivity modulation with early fuel injections for low NOx compression ignition combustion, Fuel 242 (2019) 243-254.

64. Zunqing Zheng, Mingtao Xia, Haifeng Liu, Xiaofeng Wang, Mingfa Yao, Experimental study on combustion and emissions of dual fuel RCCI mode fueled with biodiesel/n-butanol, biodiesel/2,5-dimethylfuran and biodiesel/ethanol, Energy 148(2018)824-838.

65. Haifeng Liu, Xin Wang, Zunqing Zheng, Jingbo Gu, Hu Wang, Mingfa Yao, Experimental and simulation investigation of the combustion characteristics and emissions using n-butanol/biodiesel dual-fuel injection on a diesel engine, Energy 74 (2014) 741-752.

66. Zheng Zunqing, Li Changle, Liu Haifeng, Zhang Yan, Zhong Xiaofan, Yao Mingfa. Experimental study on diesel conventional and low temperature combustion by fueling four isomers of butanol. Fuel 2015; 141:109-19.

67. Duraisamy Ganesh, P.R. Ayyappan, Rangasamy Murugan, Experimental investigation of iso-butanol/diesel reactivity controlled compression ignition combustion in a non-road diesel engine. Applied Energy 242(2019)1307-1319.

Impact Factor (JCC): 8.8746

SCOPUS Indexed Journal

NAAS Rating: 3.11

Investigation of the Engine Combustion Emissions and Engine Combustion Performance when N-Butanol as Additive Into Biodiesel

967

68. M. Gowtham, C.G. Mohan, R, Prakash, Effect of n-butanol fumigation on the regulated and unregulated emission characteristics of a diesel engine. Fuel 242(2019) 84-95.

69. Valentin Soloiu, Jose D. Moncada, Remi Gaubert, Aliyah Knowles, Gustavo Molina, Marcel Ilie, Spencer Harp, Justin T. Wiley, Reactivity Controlled Compression Ignition combustion and emissions using n-butanol and methyl oleate. Energy 165(2018)911-924.

70. Zunqing Zheng, Mingtao Xia, Haifeng Liu, Ran Shang, Guixiang Ma, Mingfa Yao. Experimental study on combustion and emission of n-butanol/biodiesel under both blended fuel mode and dual fuel RCCI mode. Fuel 226(2018)240-253.

www.tjprc.org

SCOPUS Indexed Journal

editor@tjprc.org