Optimization of Performance, Emissions, and Vibrations of a Port Fuel Injection Spark Ignition Engine Operated with Gasoline Ethanol Methanol Blends Using Response Surface Methodology

: IC Engines have played a vital role in past years and will in future years too. The only way that engines are made popular is the power they produce, which is useful in the transportation sector, with which humans’ daily lives become easier concerning time and effort. The only issues with these engines are the depletion of fossil fuels and harmful emissions. To regulate these threats, in the current study an SI engine is modified to duel fuel mode in such a way that the engine runs with hydrogen gas at different flow rates along with air. Engine speed is varied from 1800 to 3400 rpm under constant load by letting an ethanol, methanol, and gasoline mixture enter into the cylinder. Performance parameters like brake thermal efficiency, HC emissions, and vibrations produced from the engine are in agreement with the blended fuels used in this study.


Introduction
Energy demand has risen in recent years in all countries and this is having an impact on researchers, who are focusing their attention on fuels that will produce high energy with little money and less pollution or no pollution to benefit humans, the world in which we live, and future generations [1].So, focus was turned towards biofuels and alcoholic fuels like ethanol, methanol, compressed natural gas, etc. [2].Ethanol and methanol have more advantages and their productions are versatile.Compared to gasoline alcohols like ethanol and methanol, they can exhibit more power and efficiency because of their properties, like their high octane number and high heat of vaporization [3].Hydrogen has been used in spark ignition engines for many years and it has been observed that more power is produced with hydrogen utilization in SI engines than with pure gasoline because of the properties of hydrogen.The high flame velocity of hydrogen makes hydrogen much more noticeable and has received a lot of attention from authors [4].Farooq SK et al. conducted tests on a petrol engine with E30 equivalent by varying its speed from 1700 to 3300 rpm with constant load and reported that performance parameters such as brake thermal efficiency and brake specific fuel consumption enhanced compared to those with pure gasoline [5].Papla Venugopal Inbanaathan et al.conducted experiments on SI engines with E10, E30, and E50 along with gasoline and hydrogen by varying the speed of the engine.The authors noticed that E10 was better for the overall parameters of the engine when compared to E30 and E50.E30 + hydrogen has proved to have many promising results in terms of combustion, performance, and emissions [6].Xiumin Yu et al. performed a series of tests and concluded that due to the unique properties of hydrogen combustion and the performance parameters improved, brake thermal efficiency enhanced by 1.96%.Emissions Eng.Proc.2024, 66, 40 2 of 5 such as HC and CO were reduced by 32% and 0.91% with the addition of hydrogen into a petrol engine [7,8].Farooq sk et al. conducted experiments on a port fuel injection spark ignition engine with a GEM blend at various speeds and noticed good results with the Gem blend.The authors used response surface methodology for the results [9].So far, tests have been performed using ethanol, methanol, and hydrogen but a combination of GEM blends is very scarce in engine tests, and in the current study a PFI SI engine was modified into dual fuel mode to run the engine with petrol, ethanol, methanol, and hydrogen at various speeds, such as from 1800 to 3400 by an interval of 400 rpm.Results were obtained, RSM was carried out for the results, and promising conclusions were drawn.

Experimental Setup
For the investigations, as shown in Figure 1, a port fuel injection petrol engine was chosen and modified at inlet manifold into duel fuel mode in such a way that petrol and hydrogen could enter the engine cylinder to combust.Engine speed was varied from 1800 to 3400 rpm with an interval of 400 rpm; load was kept constant at 5 kg for the entire test.Hydrogen flow rates varied from 0 (Table 1).
Eng. Proc.2024, 66, x 2 of 5 Xiumin Yu et al. performed a series of tests and concluded that due to the unique properties of hydrogen combustion and the performance parameters improved, brake thermal efficiency enhanced by 1.96%.Emissions such as HC and CO were reduced by 32% and 0.91% with the addition of hydrogen into a petrol engine [7,8].Farooq sk et al. conducted experiments on a port fuel injection spark ignition engine with a GEM blend at various speeds and noticed good results with the Gem blend.The authors used response surface methodology for the results [9].So far, tests have been performed using ethanol, methanol, and hydrogen but a combination of GEM blends is very scarce in engine tests, and in the current study a PFI SI engine was modified into dual fuel mode to run the engine with petrol, ethanol, methanol, and hydrogen at various speeds, such as from 1800 to 3400 by an interval of 400 rpm.Results were obtained, RSM was carried out for the results, and promising conclusions were drawn.

Experimental Setup
For the investigations, as shown in Figure 1, a port fuel injection petrol engine was chosen and modified at inlet manifold into duel fuel mode in such a way that petrol and hydrogen could enter the engine cylinder to combust.Engine speed was varied from 1800 to 3400 rpm with an interval of 400 rpm; load was kept constant at 5 kg for the entire test.Hydrogen flow rates varied from 0 (Table 1).
Figure 1.Experimental setup for 15 lpm with interval of 3 lpm.Tests were conducted with pure petrol, E20, and GEM blend.E20 blend was prepared by mixing 80% of pure gasoline with 20% of ethanol; GEM blend was prepared by adding 10% of ethanol and 10% of methanol with 80% of pure petrol.Figure 2 represents a deviation in the BTE for fuel blends and speed.It can be noticed from Figure 2 that by increasing speed, the brake thermal efficiency is enhanced.Brake thermal efficiency is also enhanced with the change in fuel blend such that, here, pure petrol + 3 lpm hydrogen, E20 + 3 lpm hydrogen, and gasoline-ethanol and methanol + 3 lpm hydrogen are used, and when compared to these three fuel blends brake thermal efficiency was highest with GEM + 3 lpm hydrogen, because GEM + 3 lpm hydrogen exhibits a higher brake thermal efficiency than the other two blends, and also with the GEM blend without hydrogen [10], because the higher alcohol content caused oxidation of the blend and, therefore, the high latent heat of vaporization caused a rise in the brake power.Hydrogen's addition to the blend fuels also increased the brake thermal efficiency due to its higher flame velocity; the ignition energy of hydrogen is low, which makes the mixture easier to ignite [11].
Figure 2 represents a deviation in the BTE for fuel blends and speed.It ca ticed from Figure 2 that by increasing speed, the brake thermal efficiency is en Brake thermal efficiency is also enhanced with the change in fuel blend such th pure petrol + 3 lpm hydrogen, E20 + 3 lpm hydrogen, and gasoline-ethanol and m + 3 lpm hydrogen are used, and when compared to these three fuel blends brake efficiency was highest with GEM + 3 lpm hydrogen, because GEM + 3 lpm hydr hibits a higher brake thermal efficiency than the other two blends, and also with t blend without hydrogen [10], because the higher alcohol content caused oxidatio blend and, therefore, the high latent heat of vaporization caused a rise in the brak Hydrogen's addition to the blend fuels also increased the brake thermal efficienc its higher flame velocity; the ignition energy of hydrogen is low, which makes ture easier to ignite [11].

Hydrocarbons (HCs)
The fluctuation in HCs at different speeds and fuel blends is shown in F Here, we can observe that HC emissions decrease slowly with fuel blends.T highest with petrol + 3 lpm hydrogen and lowest with GEM + 3 lpm hydrogen; th to the quenching distance of hydrogen, which is shorter than that of ethanol an anol, so that flame will propagate to the walls of the combustion chamber.This m HC emissions reduce.Hydrogen does not contain carbon and so, with the add hydrogen HCs, emissions decrease.Higher oxygen in the GEM blend will result HCs when compared to pure petrol and E20; this is the other reason for redu emissions [11,12].

Emission Parameters: Variations in HCs Are Studied Here Hydrocarbons (HCs)
The fluctuation in HCs at different speeds and fuel blends is shown in Figure 3. Here, we can observe that HC emissions decrease slowly with fuel blends.They are highest with petrol + 3 lpm hydrogen and lowest with GEM + 3 lpm hydrogen; this is due to the quenching distance of hydrogen, which is shorter than that of ethanol and methanol, so that flame will propagate to the walls of the combustion chamber.This makes the HC emissions reduce.Hydrogen does not contain carbon and so, with the addition of hydrogen HCs, emissions decrease.Higher oxygen in the GEM blend will result in lower HCs when compared to pure petrol and E20; this is the other reason for reducing HC emissions [11,12].
pure petrol + 3 lpm hydrogen, E20 + 3 lpm hydrogen, and gasoline-ethanol and m + 3 lpm hydrogen are used, and when compared to these three fuel blends brake efficiency was highest with GEM + 3 lpm hydrogen, because GEM + 3 lpm hydr hibits a higher brake thermal efficiency than the other two blends, and also with t blend without hydrogen [10], because the higher alcohol content caused oxidatio blend and, therefore, the high latent heat of vaporization caused a rise in the brak Hydrogen's addition to the blend fuels also increased the brake thermal efficienc its higher flame velocity; the ignition energy of hydrogen is low, which makes ture easier to ignite [11].

Hydrocarbons (HCs)
The fluctuation in HCs at different speeds and fuel blends is shown in F Here, we can observe that HC emissions decrease slowly with fuel blends.T highest with petrol + 3 lpm hydrogen and lowest with GEM + 3 lpm hydrogen; th to the quenching distance of hydrogen, which is shorter than that of ethanol an anol, so that flame will propagate to the walls of the combustion chamber.This m HC emissions reduce.Hydrogen does not contain carbon and so, with the add hydrogen HCs, emissions decrease.Higher oxygen in the GEM blend will result HCs when compared to pure petrol and E20; this is the other reason for redu emissions [11,12].

Vibrations
Engine vibrations are the discomfort factor for a vehicle rider at increasing speeds.Figure 4 describes the effect of vibrations concerning the speed of the engine and blend.Vibrations were raised with an increment in speed and lowered with GEM + 3 lpm hydrogen compared to the other two blends due to the higher oxygen content in the fuel blend, and this leads to healthy combustion which, in return, improves the performance of the engine and avoids a large amount of knocking [13,14].

Vibrations
Engine vibrations are the discomfort factor for a vehicle rider at increasing Figure 4 describes the effect of vibrations concerning the speed of the engine an Vibrations were raised with an increment in speed and lowered with GEM + 3 drogen compared to the other two blends due to the higher oxygen content in blend, and this leads to healthy combustion which, in return, improves the perfo of the engine and avoids a large amount of knocking [13,14].Future Work: Hydrogen gas will be supplied at 3 lpm in future research w present article discusses a GEM blend with 3 lpm hydrogen, and the results o regarding its performance is very promising.The performance of the engine ca hanced by supplying more hydrogen or increasing the hydrogen flow rates by and 15 lpm.

Conclusions
Our experiment used a single-cylinder petrol engine operating in dual fuel different speeds and a variety of blends, like pure petrol + 3 lpm hydrogen, E20 hydrogen, and GEM + 3 lpm hydrogen at a constant load of 5 kg.An experim vestigation was conducted.Observations from experiments led to the following sions:

•
We successfully connected a hydrogen cylinder to the port fuel injection spa tion engine to modify it into dual fuel mode to run and conduct various test • Brake thermal efficiency was enhanced with GEM + 3 lpm hydrogen (37.23% compared to the remaining two blends, E20 + 3 lpm hydrogen (36.54%) a petrol + 3 lpm hydrogen (33.67%).

•
Ternary blends like GEM give a high amount of good and promising results f tests conducted so far.When hydrogen 3 lpm was added, the results show agreement.

Figure 1 .
Figure 1.Experimental setup for 15 lpm with interval of 3 lpm.Tests were conducted with pure petrol, E20, and GEM blend.E20 blend was prepared by mixing 80% of pure gasoline with 20% of ethanol; GEM blend was prepared by adding 10% of ethanol and 10% of methanol with 80% of pure petrol.

Figure 2 .
Figure 2. Deviation of BTE with speed and blend.

Figure 3 .
Figure 3. Deviation of HC emissions with speed and blend.

Figure 2 .
Figure 2. Deviation of BTE with speed and blend.

Figure 2 .
Figure 2. Deviation of BTE with speed and blend.

Figure 3 .
Figure 3. Deviation of HC emissions with speed and blend.

Figure 3 .
Figure 3. Deviation of HC emissions with speed and blend.

Figure 4 .
Figure 4. Deviation of vibrations with speed and blend.

Table 1 .
Conditions of engine.

Table 1 .
Conditions of engine.
3. Results and Discussion3.1.Performance Parameters: Here, One Parameter Is Investigated and Discussed Below Brake Thermal Efficiency (BTE)