Experimental and numerical investigation of spray characteristics of butanol-diesel blends

Spray characteristics are among the most important factors that affect compression ignition (CI) engines’ performance and emission levels. Flow visualisation and optical diagnostics have been widely employed in previous and current research as methods for controlling the combustion processes. This paper investigates the spray visualisation of butanol-diesel blends to determine spray characteristics such as spray penetration (S) and Average Sauter Mean Diameter (ASMD) using Ansys Forte under different ambient pressures and temperatures. The spray results showed that the spray penetration length is decreased as a result of the increased ambient pressure, while it is increased as a result of increased injection pressure of all test fuels. An increase in ambient temperature caused pure diesel penetration to become longer and wider, while butanol-diesel blends penetration becomes shorter. The ASMD of the butanol-diesel blend is higher than that of pure diesel at all operating conditions

Comparative study of spray characteristics of butanol, acetonebutanol-ethanol, butanol-acetone/diesel blends

Butanol is widely investigated as a renewable biofuel additive in Compression-Ignition (CI) engines due to its ability to improve diesel fuel properties and reduce emission levels. Because Acetone-butanol-ethanol (ABE) and butanol-acetone (BA) are intermediate mixtures in bio-butanol production, they present cost benefits compared to butanol production by reducing energy consumption and the number of recovery processes. This paper evaluates and compares the effect of using butanol (B), BA and ABE additives with diesel (D) on macroscopic spray characteristics. Spray tests were carried out in a constant volume vessel (CVV) under different injection conditions. A high-speed camera was used to record spray images. Macroscopic spray characteristics including spray penetration, spray cone angle and spray volume were measured. The experimental results showed that spray penetration (S) was increased as a result of addition of all alcohols to diesel fuel as well as of increased injection pressure; spray cone angle () was slightly widened while it was slightly narrowed as a consequence of increase fuel injection. The spray volume of the alcohol-diesel blends showed a higher value compared to that of neat diesel due to high spray penetration length. Spray penetration and spray volume of BA-diesel blend were higher compared to ABE-diesel and Bdiesel blends

The effect of butanol-acetone mixture-cottonseed biodiesel blend on spray characteristics, engine performance and emissions in diesel engine

Increasing energy demands and more stringent legislation relating to pollutants such as nitrogen oxide (NOx) and particulate matter (PM) from mineral fuels used in diesel engines have encouraged the use of biodiesel. Biodiesel fuels produced from non-edible oils have properties comparable to diesel fuel, which make them promising alternative fuels. However, there are some drawbacks associated with biodiesel as fuel for compression-ignition (CI) engines such as high viscosity and higher NOx emissions. Using an alcohol butanol-acetone (BA) or acetone-butanol-ethanol (ABE) mixture is one solution to improve blend efficiency and also to lower NOx emissions. The aim of this paper is to investigate the impact of a BA or ABE mixture blended with cottonseed biodiesel on spray characteristics, engine performance (in-cylinder pressure, brake power (BP) and specific fuel consumption (SFC)) and emission levels (NOx and carbon monoxide (CO)). The results demonstrated that BA and ABE decreased biodiesel viscosity and resulted in improved spray characteristics. BP was reduced while SFC was increased. The peak in-cylinder pressure was comparable at a lower engine speed while being slightly lower at 2000 rpm. The maximum reduction in NOx and CO was shown to be from 10BA90Bd by 13.84% and 41.5% respectively at 2000 rpm

The use of BA mixture in diesel engines: blend preparation, spray visualisation and engine performance

The increasing energy demand and more stringent legislation on engine pollutant emissions with the use of carbon-neutral fuels have motivated the use of bio-alcohols such as butanol (B). Because butanol-acetone (BA) and acetone-butanol-ethanol (ABE) are intermediate mixtures in bio-butanol production, they present cost benefits compared to butanol production as a consequence of reduced energy consumption and recovery processes. This study investigated the effect of using bio-alcohol additives with neat diesel (D) or biodiesel (Bd) on macroscopic spray characteristics, engine performance and emission concentration. The spray tests were carried out in a constant volume vessel (CVV) under different injection conditions using a high-speed camera. Engine tests were conducted using a single-cylinder direct injection (DI) diesel engine at three engine speeds (1400, 2000 and 2600 rpm) and two compression ratios (18:1 and 19:1) at full load. Spray characteristics were altered to provide for more favourable combustion using bioalcohol as an additive to D or Bd due to the low viscosity of bioalcohol which resulted in increasing both the spray penetration length and spray volume. Therefore, spray atomisation and evaporation rates could be improved. Thus, an efficient diesel engine performance can be achieved as a result of controlling injection characteristics, especially when using a promising additive like butanol or BA blended with D or Bd. Moreover, the experimental results of testing bio-alcohol with diesel showed that 10% normal-butanol-acetone (n-BA)-90% D blend showed a slight improvement in brake power (BP). The highest peak in-cylinder pressure was measured for the iso-butanol-acetone (iso-BA)-D blends and lower carbon monoxide (CO) emissions than those of the equivalent n-BA-D blend while nitrogen oxides (NOx) and unburned hydrocarbons (UHC) emission levels of n-BA-diesel blends were lower than those of the equivalent iso-BA-D blends. By investigating the effects of n-BA and iso-BA-D blends on engine performance, the BA fermentation industry could be informed about the type of butanol that should be produced. Because the different isomers of butanol have different beneficial effects on engine operation, blending them together as an additive could yield all the individual benefits of each isomer. Testing a dual blend of iso-butanolnormal- butanol (iso-B-n-B) blended with D showed that the high dual blend ratios of 10% and 13% iso-B produced higher peak in-cylinder pressures and heat release rates (HRR) as well as a substantial reduction in CO emissions. The higher blend ratios of 10% and 13% n-B produced much lower UHC emissions. A slight reduction was found in NOx emissions when increasing either n-B or iso-B, with n-butanol slightly more effective. Therefore, a blend of n- and iso-butanol could be a promising alternative to a single isomer additive (iso/n-butanol) to optimise engine performance. Finally, BA as an additive to neat cottonseed biodiesel has been investigated in relation to spray characteristics and engine performance. The experimental results of the BA-biodiesel blend revealed that the peak in-cylinder pressure for 30% BA was comparable to D and higher than that of neat Bd. BP was slightly improved for 10% BA at an engine speed of 2000 rpm while specific fuel consumption (SFC) was not significantly higher for any of the BA-Bd blends because of the smaller heating value of BA. Comparing the effect on emissions of adding BA to Bd, increasing the amount of BA reduced NOx and CO compared to neat Bd, but increased UHC. The BA blend was found to be the best additive for D or Bd fuel compared to ABE or B in related to production cost, blend properties, engine performance and emissions. Thus, the BA blend is promising as an alternative renewable environmentally friendly additive, blended with neat D or Bd without diesel engine modification that could enhance spray characteristics, improve engine performance and reduce diesel engine emissions

The impact of injector hole diameter on spray behaviour for butanol-diesel blends

Optimising the combustion process in compression ignition (CI) engines is of interest in current research as a potential means to reduce fuel consumption and emission levels. Combustion optimisation can be achieved as a result of understanding the relationship between spraying technique and combustion characteristics. Understanding macroscopic characteristics of spray is an important step in predicting combustion behaviour. This study investigates the impact of injector hole diameter on macroscopic spray characteristics (spray penetration, spray cone angle, and spray volume) of butanol-diesel blends. In the current study, a Bosch (0.18 mm diameter) and a Delphi (0.198 mm) injector were used. Spray tests were carried out in a constant volume vessel (CVV) under different injection conditions. The test blends were injected using a solenoid injector with a common rail injection system and images captured using a high-speed camera. The experimental results showed that the spray penetration (S) was increased with larger hole diameter. Spray penetration of a 20% butanol-80% diesel blend was slightly further than that of neat diesel. Spray penetration of all test fuels was increased as a result of increased injection pressure (IP), while spray cone angle (θ) was slightly widened due to the increase in either hole diameter or injection pressure. Spray volume of all test fuels was increased as a result of increased hole diameter or injection pressure. Thus, an efficient diesel engine performance can be achieved as a result of controlling injection characteristics, especially when using a promising additive like butanol blended with diesel

Experimental study of spray characteristics, engine performance and emission levels of acetone-butanol-ethanol mixture-diesel blends in a diesel engine

This paper investigates spray and engine performance of an acetone-butanol-ethanol (ABE) mixture blended with diesel fuel in a single-cylinder direct injection (DI) diesel engine. Spray images were evaluated using a high-speed camera under 300 bar injection pressure. Engine performance such as brake power (BP), brake-specific fuel consumption (BSFC) and in-cylinder pressure were measured. Exhaust gas emissions such as oxides of nitrogen (NOx), carbon monoxide (CO) and unburned hydrocarbon (UHC) were also assessed. The test was carried out at three engine speeds (1400, 2000 and 2600 rpm) at full load. The experiment results showed that: liquid penetration of ABE-diesel is longer than that of diesel. BP of ABE-diesel blends was comparable with pure diesel at 2600 rpm, while the peak in-cylinder pressure was higher compared to diesel at 2000 rpm. UHC and CO emissions were significantly reduced as a result of the addition of ABE to the neat diesel, while NOx emissions were slightly increased

Comparative assessment of spray behavior, combustion and engine performance of ABE-biodiesel/diesel as fuel in DI diesel engine

This study investigates the impact of an acetone-butanol-ethanol (ABE) mixture on spray parameters, engine performance and emission levels of neat cottonseed biodiesel and neat diesel blends. The spray test was carried out using a high-speed camera, and the engine test was conducted on a variable compression diesel engine. Adding an ABE blend can increase the spray penetration of both neat biodiesel and diesel due to the low viscosity and surface tension, thereby enhancing the vaporization rate and combustion efficiency. A maximum in-cylinder pressure value was recorded for the ABE-diesel blend. The brake power (BP) of all ABE blends was slightly reduced due to the low heating values of ABE blends. Exhaust gas temperature (EGT), nitrogen oxides (NOx) and carbon monoxide (CO) emissions were also reduced with the addition of the ABE blend to neat diesel and biodiesel by 14–17%, 11–13% and 25–54%, respectively, compared to neat diesel. Unburnt hydrocarbon (UHC) emissions were reduced with the addition of ABE to diesel by 13%, while UHC emissions were increased with the addition of ABE to biodiesel blend by 25–34% compared to neat diesel. It can be concluded that the ABE mixture is a good additive blend to neat diesel rather than neat biodiesel for improving diesel properties by using green energy for compression ignition (CI) engines with no or minor modifications

Experimental investigation of hydrated butanol-acetone (BA) and diesel blend as alternative fuel for CI engines

No abstract currently available

Investigation of ethanol production potential from lignocellulosic material without enzymatic hydrolysis using the ultrasound technique

This research investigates ethanol production from waste lignocellulosic material (sugarcane bagasse). The bagasse was first pretreated using chemicals and ultrasound techniques. These pretreatment techniques were applied separately and combined. The pretreated bagasse was then fermented anaerobically for biofuel production without enzymatic hydrolysis. The results showed higher ethanol production than those reported in the literature. The maximum ethanol production of 820 mg/L was achieved with a combination of ultrasound (60 amplitude level, 127 W) and acid (3% H2SO4 concentration). The combination of two-step pretreatment such as an ultrasound (50 amplitude level, 109 W) with acid (3% H2SO4 concentration) and then an ultrasound with alkaline (23% NaOH concentration) generated 911 mg/L of ethanol

Sugarcane Biomass as a Source of Biofuel for Internal Combustion Engines (Ethanol and Acetone-Butanol-Ethanol): A Review of Economic Challenges

The objective of this review is to provide a deep overview of liquid biofuels produced from sugarcane bagasse and to address the economic challenges of an ethanol and acetone-butanol-ethanol blend in commercial processes. The chemistry of sugarcane bagasse is presented. Pretreatment technologies such as physical, chemical pretreatment, biological, and combination pretreatments used in the fermentation process are also provided and summarised. Different types of anaerobic bacteria Clostridia (yeast) are discussed to identify the ingredient best suited for sugarcane bagasse, which can assist the industry in commercializing ethanol and acetone-butanol-ethanol biofuel from biomass sugarcane. The use of an acetone-butanol-ethanol mixture and ethanol blend in internal combustion engines is also discussed. The literature then supports the proposal of the best operating conditions for fermentation to enhance ethanol and acetone-butanol-ethanol plant efficiency in the sugar waste industry and its application in internal combustion engines