Butanol Blends Research Articles

Emission analysis in an EGR‐equipped DI diesel engine fueled by butanol‐diesel blends

AbstractIn this present work, the impacts of exhaust gas recirculation (EGR) on exhaust emissions of a diesel engine powered with the blending of butanol with mineral diesel under different engine loads were studied. Experimental tests were performed using butanol‐diesel blends on a single cylinder, constant speed, direct injection (DI) unmodified diesel engine at different proportions by vol%. A higher alcohol—Butanol of 10%, 20%, and 30% blended with mineral diesel fuel. Three different EGR rates of 10 to 30% were employed to reduce the oxides of nitrogen (NOx) emissions that prevailed at higher engine loads. Experimental results revealed that by increasing the EGR rates reduces nitrogen oxide emissions by up to 32% at higher loads. Whereas smoke opacity barely raised to an EGR rate of 20%. There was a rise in hydrocarbon (HC) emissions and a slight surge in carbon monoxide (CO) emissions found with butanol‐diesel blends rather than mineral diesel. NOx emissions were decreased by 29% for 70% Diesel + 30% Butanol (Bu30) blend with EGR 30% than mineral diesel fuel. There is an increase in smoke opacity with engine load because of the burning of a higher amount of energy to generate higher brake power. Smoke opacity is decreased to 68.9% using Bu30 than conventional diesel. Overall, it was found that blends of 30% of butanol and 70% of diesel can be employed in existing unmodified diesel engines.

Application of Taguchi design in optimization of performance and emissions characteristics of n-butanol/diesel/biogas under dual fuel mode

Combustion experts are in search of some alternative fuel from last few decades owing to diminishing petroleum products and unexpected variations in habitat, which are result of venomous emissions from the CI engines. The present investigation intended to assess the performance and emission parameters of a diesel engine by fueling it with pilot fuel (blends of diesel and n-butanol) and primary fuel (Biogas). Results revealed that BTE, HC and CO increases whilst NOx and smoke emissions were reduced by using the pilot and primary fuel together in relation with natural diesel. Experimentation was done using Taguchi L9 orthogonal array design. The engine load, flow rate of biogas and butanol in fuel blend percentage were selected as input parameters whereas brake thermal efficiency (BTE) and emission characteristics i.e., HC, CO, NOx and smoke were chosen as response variables. ANOVA was carried out for the responses by utilizing MINITAB software. The higher value of raw data and S/N ratio for BTE was noted with high engine load, low flow rate of biogas and butanol blend percent. For the emission characteristics i.e., HC, CO and smoke, lower raw data and high S/N ratio values were attained in the order of rank engine load > butanol blend percent > biogas flow rate while the similar values for NOx were attained in the rank engine load > biogas flow rate > butanol blend percent. Taguchi design was noted to be an effective tool for the optimization of various response parameters and the optimum levels of input parameters were calculated after analysis. Full engine load for BTE and HC, Biogas flow rate of 15 lpm for BTE, HC and CO, and 20 % of butanol blend for HC, CO and smoke were found to be the optimum conditions for the conducted experimentation.

Effectiveness of Butanol and Deposit Control Additive in Fuel to Reduce Deposits of Gasoline Direct Injection Engine Injectors

Modern internal combustion engines are designed to meet new emission standards and reduce fuel consumption. The wide application of direct fuel injection is associated with the problem of injector contamination. It leads to a deterioration of the engine’s environmental performance. The paper aims to evaluate the effect of applying gasoline–butanol blends and appropriate additives on the formation of injector deposits. The research involved testing the engine on a dynamometer, evaluating the injector tips visually at 1000× magnification, and registering the fuel spray using high-speed imaging techniques with a laser and halogen lighting source. The effect of engine operating with the reference fuel was to coke the injector tip with a linear pattern. It increased the linear injection time to keep the engine’s operating point constant over the 48 h test. The application of 20% (v/v) butanol reduced deposit formation. The best scavenging results were obtained by extending the engine operating time by the next 24 h and using a cleaning procedure. The procedure included a cleaning additive in addition to butanol. Among the cases analyzed, a combination of butanol and DCA (Deposit Control Additive) was the best method for injector patency restoration.

Effect of inherent oxygen mass fraction of alcohol blends with diesel on combustion and emission parameters

AbstractIncreasing air pollution and implementation of stricter emission regulations led to the research for the clean combustion concept of combustion engines. To resolve this concern, it is important to look for a clean and stable combustion concept that can adapt easily to an old existing engine as well as newer engines. The present study was performed to investigate the combustion stability and emission for blends of methanol (M), ethanol (E), and butanol (B) to evaluate the effect of their inherent oxygen content. Alcohol blends were prepared for two different oxygen mass fractions of 2.5% and 5% oxygen, m/m (defined as M2.5, E2.5, B2.5 and M5, E5, B5). For this, different volume fraction of respective alcohol was required (M2.5 and M5 contained 5.2% and 10.3% methanol respectively, E2.5 and E5 contained 7.4% and 14.8% ethanol respectively, B2.5 and B5 contained 11.7% and 23.3% butanol respectively). Detailed combustion analysis was performed for the alcohol blends (2.5% and 5% oxygen mass fraction) using the parameters like cycle‐to‐cycle analysis, coefficient of variation, combustion phasing etc. M5 showed the better stable combustion considering the lowest coefficient of variation for CA50 and indicated mean effective pressure. Moreover, the performance of E5 showed improved efficiency with brake thermal efficiency (BTE) of 27.94% and reduced brake specific fuel consumption. Significant reductions in hydrocarbon (HC), smoke and carbon dioxide (CO2) emissions were recorded for 2.5% and 5% oxygenated condition. M5 showed lowest emission level among tested fuel with 20% lower oxide of nitrogen (NO) and 50% lower HC.

Combustion and emission characteristics investigation of a marine diesel engine powered by diesel/biodiesel/n‐butanol blends

AbstractIn this paper, a three‐dimensional simulation model of the engine cylinder is established using commercial simulation software AVL‐Fire, and the accuracy of the model is verified with experimental results. The effects of diesel/biodiesel/n‐butanol blends on diesel engine performance, and combustion and emissions characteristics were investigated by performing simulation operations on the model. The combustion process in the cylinder was simulated for 0%, 5%, 10%, 15%, and 20% of n‐butanol in the fuel mixture. The results showed that at 75% load, the brake thermal efficiency of D95N5, D90N10, D85N15, and D80N20 engines increased by 0.84%, 1.68%, 2.48%, and 3.19%, respectively, and soot emissions decreased by 2.76%, 5.52%, 8.25%, and 10.96%, respectively, compared with D100. However, the brake power of the engine was reduced, the brake ratio fuel consumption increased, and NOx emission increased. In addition, at all loads, soot and CO emissions decrease as the percentage of n‐butanol in the fuel mixture increases.

Numerical Study of PAHs and Soot Emissions from Gasoline–Methanol, Gasoline–Ethanol, and Gasoline–n-Butanol Blend Surrogates

Soot formation is an intricate phenomenon, and soot propensity of a fuel is interwoven with the fuel composition, physical and chemical properties, and combustion environment. The present study examines the hypothesis that in addition to the chemical composition of the fuel, the sooting nature of the fuel is closely coupled with its chemical property known as octane sensitivity (S). With this motivation, the present study numerically investigates the effects of gasoline surrogate composition and its property, octane sensitivity (S), on polycyclic aromatic hydrocarbons (PAHs) and soot emissions. Four-component toluene primary reference fuel (TPRF)–alcohol blends, comprising iso-octane, n-heptane, toluene, and one of the three different alcohols- methanol, ethanol, and n-butanol, are used as gasoline surrogates. A total of 320 TPRF–alcohol mixtures, with S in the range of 1–10, are examined under laminar counterflow diffusion flame conditions. A detailed chemical mechanism coupled with a comprehensive soot model, which includes reactions for soot inception, surface growth, PAH condensation, and oxidation, is adopted. The analysis indicates that the toluene content in the fuel mixture has a prominent effect, while the alcohol content and octane sensitivity of the fuel have a weak correlation with the PAHs and soot. Thus, it is not clear if any of these three variables, namely, toluene content in the fuel, alcohol content in the fuel, and S, are individually sufficient to characterize the PAHs and soot across various blends. For this reason, a new variable (XCHO) based on the elemental composition of the fuel mixture is identified and it is shown that XCHO along with S of the fuel characterize soot emissions satisfactorily. Further, a reaction path analysis indicates that the efficacy of alcohols in reducing soot emissions follows the order: methanol > ethanol > n-butanol.

Formation of polycyclic aromatic hydrocarbons and regulated emissions from biodiesel and n-butanol blends containing water

To increase the use of biofuels in diesel engines and reduce harmful emissions emitted from diesel fuel, biodiesel and higher alcohols are fuel sources at the forefront of research. The aim of this study is to understand the effect of water-containing n-butanol-biodiesel blends on regulated emissions, emphasizing nitrogen oxides (NOx) and polycyclic aromatic hydrocarbons (PAHs), which are harmful for the environment and engine durability. 10% n-butanol (B90Bu10) and 10% n-butanol-1% water (B89Bu10W1) were blended with 89% waste-oil biodiesel and tested in a diesel engine at four engine loads at a constant engine speed. PAH samples were analyzed using gas chromatography-mass spectrometry (GC-MS). Results showed B100, B90Bu10 and B89Bu10W1 blends increased break specific fuel consumption (BSFC), exhaust gas temperatures (EGT), carbon monoxide (CO) and hydrocarbon (HC) emissions. However, NOx emissions significantly decreased using butanol and butanol-water blends. Compared to diesel, biodiesel and blended fuels significantly reduced total PAHs and PAH toxicity up to 75.0%. However, B89Bu10W1 increased total PAH and PAH toxicity by 35.7%. Overall, the biodiesel-butanol blend, which emits less carcinogenic pollutants and low-cyclic PAHs than water-containing fuel, was found to reduce the risk of wetstacking in diesel engines operating under low loads.

Optical diagnostic study of coal-to-liquid/butanol blend and dual-fuel combustion of a CI engine

The clean alternative fuel represented by coal-to-liquid (CTL) and butanol has attracted the attention of researchers. Previous research by our group has shown that both CTL/butanol blend and dual-fuel combustion can alleviate the problems when burning pure CTL in compression-ignition (CI) engines. To investigate the mechanism of CTL/butanol blend and dual-fuel combustion improving premixed combustion and reducing particulate emissions, an optical diagnostic study was conducted on a self-built dual-fuel optical engine with flexible and adjustable combustion boundary conditions for CTL/butanol blend and dual-fuel combustion. The images of flame development had been acquired and analyzed by means of high-speed photography combined with two-color method. The results show that the blending of butanol into the CTL reduces the reactivity of the blended fuel and leads to a prolonged ignition delay (ID), while the ignition timing of the CTL/butanol dual-fuel combustion is mainly controlled by the CTL with high reactivity, so the ID varies slightly with the butanol addition in the dual-fuel combustion. During the combustion of blend fuel mode, a visible flame is formed near the cylinder wall and the flame in the center of the cylinder is not obvious, whereas during the combustion of dual-fuel mode there are two distinct kinds of flame both around the cylinder wall and in the center of the cylinder. Both butanol blending and butanol pre-spraying can significantly reduce the flame area and flame natural luminosity during combustion, but the effect of butanol blending is more obvious. So that increasing the proportion of butanol is effective in reducing the average in-cylinder temperature at both the CTL/butanol blend and dual-fuel combustion modes. However, compared to dual-fuel combustion, CTL/butanol blend combustion can reduce the in-cylinder temperature gradient more effectively. Since soot is more likely to be generated in the high temperature region, blending butanol into CTL is more effective in reducing soot generation than pre-spraying butanol into the intake.

Methanol/Ethanol/Butanol-Gasoline Blends Use in Transportation Engine—Part 1: Combustion, Emissions, and Performance Study

Abstract Primary alcohols such as methanol, ethanol, and butanol have exhibited excellent potential as possible alternative fuels for spark ignition (SI) engines because they are renewable, cleaner, and safer to store and transport. However, it is important to investigate the technical feasibility of adapting these primary alcohols in existing SI engines. In this research, a multi-point port fuel injection (MPFI) system equipped SI engine was used for assessing and comparing the combustion, performance, and emission characteristics of various alcohol-gasoline blends (gasohols) vis-à-vis baseline gasoline. The experiments were performed at different engine loads at rated engine speed. Experimental results exhibited relatively superior combustion characteristics of the engine fueled with gasohol than the baseline gasoline, especially at medium engine loads. Among different test fuels, the methanol-gasoline blend (GM10) exhibited relatively more stable combustion characteristics than the ethanol-gasoline blend (GE10) and butanol-gasoline blend (GB10). In this study, relatively superior engine performance of the gasohol-fueled engine was observed at all engine loads and speeds. GB10 exhibited the highest brake thermal efficiency (BTE), followed by GM10 amongst all test fuels. The effect of improved combustion was also reflected in the emission characteristics, which exhibited that GB10 emitted relatively lower carbon monoxide (CO) and hydrocarbons (HCs) than other test fuels. GB10 emitted relatively higher nitrogen oxides (NOx) than GM10 and GE10. Unregulated emission results exhibited that the engine fueled with gasohols emitted relatively lower sulfur dioxide (SO2), ammonia (NH3), and various other saturated and unsaturated HCs than the baseline gasoline. The GM10-fueled engine was relatively more effective in reducing unregulated emissions among all test fuels. This study concluded that methanol and butanol blending with gasoline resulted in superior engine performance and reduced harmful emissions in MPFI transport engines. This offered an excellent option to displace fossil fuels partially and reduce emissions simultaneously.

Effect of Abe and Butanol Blends with N-Dodecane in Different Volume Ratios on Diesel Combustion and Soot Characteristics in Ecn Spray a Conditions

Effect of Abe and Butanol Blends with N-Dodecane in Different Volume Ratios on Diesel Combustion and Soot Characteristics in Ecn Spray a Conditions

Optimization of Ci Engine Performance Using Ternary Blends of Butanol, Biodiesel and Diesel Doped with Al2o3 Nanoparticles

Optimization of Ci Engine Performance Using Ternary Blends of Butanol, Biodiesel and Diesel Doped with Al2o3 Nanoparticles

Optimization Technique Approach on a Two-Stroke Engine with Coated Piston and Gasoline Blends

The performance and emissions affected by the coating have been analyzed in this study. In the present experimental investigation with gasoline blends of butanol and propanol along with magnesium partially stabilized zirconium (Mg-PSZ) as thermal barrier coating on piston crown of 100 microns. The samples of gasoline blends were blended with petrol in 20:80 ratios (20% of ethanol and 80% of gasoline, 20% of butanol and 80% of gasoline). The specific standard parameters have been modified with Mg-PSZ coated petrol engine with aid of design of experiment by Taguchi with grey relational analysis optimisation method, for improving the engine performance and emission reduction. The result shows that modified Mg-PSZ coated piston at B20. Finally, the results of the experiments were compared with uncoated and coated engine and optimised parameters have been identified for Mg-PSZ coated modified piston using Taguchi grey relational method.

Performance and Exhaust Emissions of a Spark Ignition Internal Combustion Engine Fed with Butanol–Glycerol Blend

Investigation of a new type of fuel for the internal combustion engine, which can be successfully used in both the power generation and the automotive industries, is presented in this article. The proposed fuel is a blend of 75% n-butanol and 25% glycerol. The engine tests conducted with this glycerol–butanol blend were focused on the performance, combustion thermodynamics, and exhaust emissions of a spark-ignition engine. A comparative analysis was performed to find potential similarities and differences in the engine fueled with gasoline 95 and the proposed glycerol–butanol blend. As measured, CO exhaust emissions increased, NOx emissions decreased, and UHC emissions were unchanged for the glycerol–butanol blend when compared to the test with sole gasoline. As regards the engine performance and combustion progress, no significant differences were observed. Exhaust temperature remarkably decreased by 3.4%, which contributed to an increase in the indicated mean effective pressure by approximately 4% compared to gasoline 95. To summarize, the proposed glycerol–butanol blend can be directly used as a replacement for gasoline in internal combustion spark-ignition engines.

Combustion characteristics of butanol‐ Jet A‐1 fuel blends in a swirl‐stabilized combustor under the influence of preheated swirling air

Biofuels are carbon-neutral alternative fuels, which have emerged as an important source of energy for the aviation industry to reduce greenhouse gas emissions. Butanol is considered an emerging biofuel with properties that are suited for application in gas turbine engines. It is traditionally produced through the fermentation process of biomass (acetone-butanol-ethanol fermentation). To examine the feasibility of butanol as operating fuel, the combustion characteristics of butanol and butanol/Jet A-1 blends are examined in a lab-scale swirl stabilized burner, with emphasis on the effect of preheating because of the variation of inlet air temperature during flight operation. To rich the constant air temperature to 150°C, the incoming air (main air) is preheated and investigated for various equivalence ratios. Compared to neat Jet A-1, the flames of the butanol/Jet A-1 blends have shown a better effect on global emission characteristics with comparable temperature distribution on adding butanol to Jet A-1. A 50% butanol-loaded blends show a reduction of 29% CO and 24% NOx compared to neat Jet A-1 whereas 30% loading follows a similar trend, and the pollutant emission is slightly higher than the 50% blend case. Additionally, both 30% and 50% butanol blends show a comparable flame temperature distribution, which is higher than neat Jet A-1.

Distributed combustion of diesel–butanol fuel blends in a mixture temperature-controlled burner

Butanol is a promising candidate to increase the share of renewable fuels in our liquid fuel portfolio for industry and transportation. The combustion of four B0-B50 diesel fuel-n-butanol blends was investigated in a Mixture Temperature-Controlled burner, a novel archetype of turbulent swirl burners for ultra-low emissions to provide data on the effect of butanol blending for steady-operating applications. Stable combustion of blended fuels was limited to an equivalence ratio of 0.76 in our burner, which is a notable drawback compared to that of diesel fuel in this test system. Distributed flames feature low luminosity and single-digit CO and NOX emissions in ppm at 15% O2 level, the representative for gas turbines, fulfilling all the current NOX regulations with 86% margin on average. The CO emission was inferior in all cases. The chemiluminescent intensity of OH* was sufficient for evaluation at all flames except for distributed combustion, which is the favorable flame type. The acoustic spectrum of various fuels under identical conditions was highly similar, concluding easy interchangeability from a combustion acoustics point of view. Moreover, the noise of distributed combustion was 10 dB lower than that of straight flames for all fuels and conditions.

Investigating Combustion Process of N-Butanol-Diesel Blends in a Diesel Engine with Variable Compression Ratio

The search for alternative fuels for internal combustion engines is ongoing. Among the alternatives, plant-based fuels can also be mentioned. Alcohol is not a common fuel for diesel engines because the physical and chemical properties of the alcohols are closer to those of gasoline. In our research, the combustion properties of diesel-n-butanol mixtures have been investigated to obtain results on the effect of butanol blending on combustion. Among the combustion properties, ignition delay, in-cylinder pressure, and heat release rate can be mentioned. They have been observed under different compression conditions on an engine on which the compression ratio can be adjusted. The method used was a quite simple one, so the speed of the engine was set to a constant 900 rpm without load, while three compression ratios (19.92, 15.27, and 12.53) were adjusted with a fuel flow rate of 13 mL/min and the pre-injection angle of 18° BTDC. Blending butanol into the investigated fuel does not significantly affect maximal values of indicated pressure, while much more effect on the pressure rising rate can be detected. Furthermore, heat release rate and ignition delay increased at every compression ratio investigated. Despite the low blending rates of butanol in the mixtures, butanol significantly affects the combustion parameters, especially at high compression ratios.

A Comparison of Ethanol, Methanol, and Butanol Blending with Gasoline and Its Effect on Engine Performance and Emissions Using Engine Simulation

Air pollution, especially in large cities around the world, is associated with serious problems both with people’s health and the environment. Over the past few years, there has been a particularly intensive demand for alternatives to fossil fuels, because when they are burned, substances that pollute the environment are released. In addition to the smoke from fuels burned for heating and harmful emissions that industrial installations release, the exhaust emissions of vehicles create a large share of the fossil fuel pollution. Alternative fuels, known as non-conventional and advanced fuels, are derived from resources other than fossil fuels. Because alcoholic fuels have several physical and propellant properties similar to those of gasoline, they can be considered as one of the alternative fuels. Alcoholic fuels or alcohol-blended fuels may be used in gasoline engines to reduce exhaust emissions. This study aimed to develop a gasoline engine model to predict the influence of different types of alcohol-blended fuels on performance and emissions. For the purpose of this study, the AVL Boost software was used to analyse characteristics of the gasoline engine when operating with different mixtures of ethanol, methanol, butanol, and gasoline (by volume). Results obtained from different fuel blends showed that when alcohol blends were used, brake power decreased and the brake specific fuel consumption increased compared to when using gasoline, and CO and HC concentrations decreased as the fuel blends percentage increased.

Comparative investigation of ignition behavior of butanol isomers using constant volume combustion chamber under diesel-engine like conditions

Butanol is a sustainable carbon–neutral fuel that can be derived from a variety of biomass resources. It can be potentially be used as an alternative fuel to blend with diesel to decrease greenhouse gas and pollutant emissions. In this paper, three butanol isomers (n-butanol, tert-butanol, and iso-butanol) are blended with diesel in various volume ratios. The combustion characteristics of butanol isomers are experimentally determined in a constant volume vessel under engine-like conditions. The effects of blend ratio, chamber temperature, and chamber pressure on ignition delay and combustion process are investigated. It is shown that the ignition delay decreases at high temperature and at low butanol blend ratio regardless of the isomer type. The combustion characteristics of butanol/diesel blends differ from neat butanol. Both low temperature heat release (LTHR) and high temperature heat release (HTHR) are observed for the three butanol isomers/diesel blends. Under current operating conditions, the ignition delay of three butanol isomer/diesel blends is ordered according to iso-butanol > n-butanol > tert-butanol. Notwithstanding its higher octane number, tert-butanol/diesel blends show the fastest LTHR and thereafter the shortest ignition delay. This is because of the absence of H atom on the alpha carbon of tert-butanol, which contributes to consumption of OH radicals. Consequently, oxidation of diesel is less suppressed. However, the HTHR of tert-butanol/diesel blends is much slower than that of n-butanol/diesel. At 80% blend ratio, a higher chamber pressure is required to improve the reactivity and ignition. Overall, the low reactivity of butanol is beneficial to be applied in diesel engines to increase the fuel/air mixing time so as to attenuate soot emissions.

Time-Resolved Endoscopic Evaluation of Spatial Temperature and Soot Distribution in a Butanol-Diesel Blend Fueled Direct Injection Compression Ignition Engine

Abstract In situ spatial soot and temperature distributions were investigated experimentally for B20 (20% v/v butanol and balance mineral diesel blend) vis-a-vis mineral diesel using endoscopic visualization technique. Endoscope captured the in-cylinder combustion images in a production-grade direct injection compression ignition (DICI) engine at varying engine operating conditions. A comparative combustion data analysis using pressure-crank angle history and the captured endoscopic images was performed. An attempt was made to correlate the results of these two experimental investigations. Combustion duration (CD) obtained from the endoscopic images was relatively longer than the CD calculated from the thermodynamic analysis. Most research on soot and NOx emitted from the engine using a raw exhaust gas emission analyzer provides bulk, time-averaged, and cycle-averaged information about the pollutant formation. This investigation is unique wherein the spatial or time-resolved soot and NOx formation (Via spatial temperature distribution) are evaluated. The findings of this study support the research finding available in the open literature using an emission analyzer. This study and the technique therein on the deployment of engine endoscopy as an emerging optical technique is potentially useful to original automotive manufacturers (OEMs) in designing more efficient engines, capable of meeting upcoming stringent emission norms.

Bibliometric Studies on Emissions from Diesel Engines Running on Alcohol/Diesel Fuel Blends. A Case Study about Noise Emissions

The growing demand for fossil fuels, the rise in their price and many environmental concerns strengthen the incessant search for fuel alternatives. Recently, traffic noise has been described as a threat to human health and the environment, being responsible for premature deaths. In this context, the usage of alcohol/diesel fuel blends in diesel engines has gained increasing impact as a substitute fuel for use in internal combustion engines. Moreover, alcohol can be derived from environmentally friendly processes, i.e., fermentation. Furthermore, alcohols can enhance combustion characteristics due to a rise of the oxygen concentration, thus decreasing major emissions such as soot and reducing knock. The commonly used alcohols blended with diesel fuel are methanol and ethanol, recently followed by butanol. In contrast, there are very few studies about propanol blends; however, emissions reduction (including noise) could be remarkable. In the present work, an analytical literature review about noise and exhaust emissions from alcohol/diesel fuel blends was performed. The literature review analysis revealed a continuous increase in the number of publications about alcohol/diesel fuel blend exhaust emissions since 2000, confirming the growing interest in this field. However, only few publications about noise emission were found. Then, an experimental case study of noise emitted by an engine running on different alcohol (ethanol, butanol and propanol)/diesel fuel blends was presented. Experimental results showed that although diesel fuel provided the best results regarding noise emissions, butanol displayed the least deviation from that of diesel fuel among all tested alcohol blends. It may be concluded that tested alcohol/diesel fuel blends in general, and butanol blends in particular, could be a promising alternative to diesel fuel, considering noise behavior.