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The advent of biofuel as a fossil petroleum substitute has been a revolutionary concept in the realm of combustion, but it lacks some qualities that, if addressed, could improve physio-chemical properties and promote energy sustainability. Recently, introducing nanoparticles (NPs) as an additive in fuel for combustion engines has become an effective practice particularly in the automobile industry, to optimize combustion efficiency and minimize emissions. Previous researchers discovered that adding NPs into biodiesel fuel improved overall engine operation performance. Thus, the objective of the research is to summarize existing research findings on nanoparticles effects on fuel properties and engine performance. The paper investigates biofuels, bio-fuel generation classifications, nano-fuel stability, performance, and limitations, as well as current research on the influence of NPs on combustion fuel properties and engine efficiency. Prior to this, researchers have discovered that employing NPs with appropriate additives and concentrations with optimal solubility significantly reduced emissions. In comparison to basic biofuel, adding CeO2 NPs to biofuel boosted brake thermal efficiency (BTE) for low and high operation by 4.1 and 12.02%, respectively. Carbon II Oxide and unburnt hydrocarbon emissions were reduced by 16.13 and 17.59%, respectively, in comparison to pure biofuel under C20-D80 + CeO2 20 ppm. However, due to the biofuel's oxygen concentration, CO2 and NOx emission reductions were not as significant. The findings indicate that utilizing a single bio-fuel generates minimal effective power, yet by incorporating nanoparticles optimizes the operation. Furthermore, future direction of the related work will be discussed particularly on the potential benefits of incorporating NPs in fuel.

Transmission gear ratio usually affects transportation fuel usage during travelled on road. The manner of gear usage is one of the main factors affecting the fuel consumption of vehicles. By using the neutralizing driving data collection, the vehicle Toyota Hilux 2.5 liters has been used to conduct the experiment to determine the fuel consumption, based on the average vehicle speed, engine speed and gear usage. Some parameters were investigated, with a special emphasis on the relation between the engine speeds and vehicle speeds, also presenting an example of using the information provided by the OBD to determine the gear ratios. In the end, the gear steps and the way they are used while driving the vehicle were identified. It is found that each gear usage can have a specific impact on fuel consumption and the usage of first gear indicates higher average fuel consumption with 60.5% with 35.8 liters/100km compared with second gear. In conclusion, the fuel consumption is significantly determined by a proper gear selection

Transportation contributes a major share of the fuel usage from total vehicles in developing countries. The manner of gear usage is one of the main factors affecting the fuel consumption of motor vehicles. The presented results came from the tests conducted on Toyota Hilux 2.5 liters vehicle to determine the fuel consumption, based on the average vehicle speed, engine speed and gear usage collected from using the neutralizing driving data collection. Some parameters were investigated, with a special emphasis on the relation between the engine speeds and vehicle speeds, also presenting an example of using the information provided by the OBD to determine the gear ratios. In the end, the gear steps and the way they are used while driving the vehicle were identified. It is found that each gear usage can have a specific impact on fuel consumption and the lowest fuel consumption recorded under fifth gear with 9.75 liters/100km which reduction of 4.3% reduction compared with 4th gear. In conclusion, the fuel consumption is significantly determined by a proper gear selection.

In the present study, torrefaction of palm kernel shell (PKS) and petcoke blends was performed for the production of solid biofuels with high energy density. The torrefaction process was performed for mixtures with various mixing ratios (by weight) from 90:10 to 60:40 (PKS:petcoke). For torrefaction under various temperatures of 250℃ to 300℃, the mixing ratio of 60:40 was used. Meanwhile, residence time and nitrogen flow rate were fixed at 30 minutes and 1 l/min, respectively. In general, the fixed carbon and ash contents increased, while the moisture and volatile matter contents decreased after torrefaction. It has been elucidated that mass yield is a dominant factor that affects the energy yield of torrefied mixtures rather than the higher heating value (HHV) ratio. Based on the energy yield and ultimate analysis, it was found that a higher amount of petcoke and higher temperature give better performance, thus causing the torrefied mixture to become very close to coals region in Van Krevelen diagram. In this case, the mixture with a mixing ratio of 60:40 torrefied under the temperature of 300℃ gives the best performance. It was also found that this mixture is thermally stable than the mixture torrefied at 250℃.

Microalgae has a greater potential to be used as biodiesel feedstock compared to vegetable oils. Biodiesel derived from microalgae produce more quantity of oil, consume less space, and could be grown on unsuited land for agriculture. Sunlight is essential to produce microalgae biodiesel. Microalgae production is largely dependent on light levels that are affected by day-to-day and seasonal variations. Indonesia, with its tropical climate and abundant sunlight throughout the year is very suitable for microalgae life. Yet, the development of microalgae biodiesel in Indonesia has not reached significant milestones. This review article aims to discuss future direction of algae biodiesel in Indonesia. A number of microalgae strain found in Indonesia is highlighted. Several challenges in the study of microalgae is also presented. Lastly, this article points out to the need of research on the direct application of microalgae in internal combustion engines.

The implementation of alternative fuels, such as biodiesel, in engines has been shown to be a feasible strategy to control greenhouse gas (GHG) emissions. The blending of biodiesel with diesel can reduce emissions of carbon monoxide (CO) and carbon dioxide and reduce soot formation. Nonetheless, biodiesel combustion comes with low thermal efficiency, elevated emissions of nitrogen oxides (NOx) and carbon deposition issues. Recently, the addition of gasoline to diesel–biodiesel blends has been proposed to compensate for the downsides of biodiesel combustion. In the current review, the viability of using this ternary fuel blend in engines is thoroughly reviewed. The review first assesses the environmental and health issues caused by conventional fuels, mitigation schemes to control GHG emissions and alternative fuels as a decarbonizing technology. The combustion and emissions characteristics of diesel–biodiesel–gasoline mixtures are discussed in detail. Finally, the status, challenges and prospects of applying the alternative fuel mixture in engines are appraised. This work has revealed that the mixing of gasoline with diesel–biodiesel blends brings about elongated ignition delay, increased heat release rate and in-cylinder pressure at high loads. Additionally, by adding gasoline, the combustion duration is shortened and soot, CO and unburned hydrocarbon emissions are suppressed, while NOx emissions are slightly increased. Combustion stability is found to be partially disrupted in the presence of gasoline whereas fuel economy (at medium and high loads) is improved by the addition of gasoline. To support the wider deployment and commercialization of this fuelling strategy in the transportation sector, favourable legislation and/or fiscal incentives are needed in countries around the world. This would encourage researchers, fuel producers and engine manufacturers alike to solve challenges such as biodiesel feedstock costs, fuel quality, fuel storage management and engine warranty issues.

In this research, the spray combustion, soot formation and exhaust emissions of diesel, biodiesel, gasoline fuels and their mixtures are analysed in a constant volume chamber. A multicomponent kinetic mechanism (CDBG) suitable for diesel-biodiesel-gasoline mixtures developed by our research group is utilised, and the associated physicochemical properties are thoroughly calculated. Adaptive mesh refinement scheme with appropriate mesh independency analysis are applied. Liquid penetration length, lift-off length, ignition delay and soot formation have been benchmarked against experimental data in the literature. A hybrid RANS-LES model, known as DES model, is used to simulate the turbulent condition. The effects of different ambient temperature/oxygen levels on the flame structure, soot formation and emissions of different ternary mixtures of D75|BD20|G5, D70|BD20|G10 and D65|BD20|G15 were analysed. D65|BD20|G15 resulted in a lower soot mass yield than that of BD100 (pure biodiesel) and D100 (pure diesel) for about 35% and 27%, respectively, at T = 900 K | O2 = 15%. Greater soot mass reductions for the tested fuels were captured by the decrease in ambient temperature from 900 K to 800 K by a factor of ∼1/3 (same ambient O2 concentration). Lower nitrogen oxides (NOx) emissions were obtained for D100 by factors of ∼1/2 at T = 900 K | O2 = 15% compared to BD100. Gasoline-added mixtures revealed lower NOx compared to BD100 (∼20%) yet still higher than D100. Lower carbon dioxide (CO2) and carbon monoxide (CO) emissions were captured for D65|BD20|G15 compared to BD100 and D100.

Today, a growing interest to use Acetone-Butanol-Ethanol (ABE) as a biofuel has emerged. Fuel properties play important roles to determine engine’s performance, combustion, and emission behaviors. ...

Recent developments in internal combustion engines have heightened the need for alternative biofuel. In the last five years, acetone-butanol-ethanol (ABE) has been extensively studied as a promisin...

Autonomous vehicles have the potential to reduce the risk of accidents as they eliminate the element of human error from driving. Lack of attention, poor judgement, or physical limitations may lead to road incidents. Thus, the development and deployment of autonomous vehicles should be a priority. However, before being publicly available, autonomous vehicles must be tested to ensure their viability and safety by conducting public road testing. Autonomous vehicles have been designed and tested since the early 1900s; however, deployment of fully autonomous vehicles on public roads only started in the 2000s. Numerous countries have developed guidelines for public road testing, but those rules are not uniform, and discrepancies occur between nations. Issues such as vehicular safety, registrations, authority, insurance, cybersecurity, and infrastructures weigh differently in each country. Synthesizing these diverse national regulations into global guidelines would promote the safety and sustainability of autonomous vehicle testing and benefit all parties interested in autonomous vehicles.

In this research, a multi-input multi-output artificial neural network (MIMO-ANN) is developed, in which 14 features associated with the engine performance and stability, emissions, combustion and ignition characteristics of diesel-biodiesel-gasoline mixtures are meant to be modelled by a diverse combination of engine/combustion parameters. The selected targets comprise brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), combustion efficiency, coefficient of variance (COV), NOx, CO2, CO and HC emissions, exhaust temperature (Texh), in-cylinder pressure (Pcyl), maximum pressure rise rate (MPRR), heat release rate (HRR), combustion duration (CD) and ignition delay (ID). The inputs variables entail the load, speed, compression ratio, gasoline, biodiesel and diesel ratios, crank angle (CA), injection temperature (Tinj), injection pressure (Pinj), brake mean effective pressure (BMEP) and start of injection (SOI). Sensitivity analysis and outlier detection are applied in order to eliminate less-effective inputs/data points. The prepared data sets are then used to train and test the ANN model, in conjunction with benchmarking the model outcomes using coefficient of determination (R2), average absolute relative deviation (AARD) and relative mean squared errors (RMSE). The R2 ranged within 0.9804–0.9998, which is close to unity, proving that the proposed network is accurately capable of predicting the intended combustion characteristics.

Homogeneous charge compression ignition (HCCI) engine has emerged as a promising combustion technology. Theoretically, an HCCI engine can reduce both NOx and soot emissions significantly down to almost zero levels. This is possible as a result of two fundamental processes that occur in the HCCI engine, i.e. the homogeneous mixture and its autoignition characteristics. Neither spark plug nor injector is used in the HCCI engine. The autoignition of the homogeneous mixture is solely influenced by its chemical reactions inside the combustion chamber. However, this is where the problems start to occur. At low loads or too lean mixtures, misfire may occur, thus increasing the HC and CO emissions. At high loads or too rich mixtures, soot emissions and knocking tendency may increase. Moreover, an undesirable pressure rise due to knocking will increase the combustion temperature and potentially increase the probability of NOx formation. Therefore, the operating range of HCCI engine is very limited only to part loads. Controlling its combustion phasing play an important role to extend the narrow operating range of the HCCI engine. Despite numerous review articles have been published, classification of the approaches to achieve HCCI combustion in diesel engines were rarely presented clearly. Therefore, this review article aims to provide a concise and comprehensive classification of HCCI combustion so that the role and position of each strategy found in the literature could be understood distinctively. In short, two important questions must be solved to have successful HCCI combustion; (1) how to form a homogeneous mixture? and (2) how to control its auto-ignition?

Indonesia and Malaysia are currently holding prominent roles in the global palm oil market. Both countries are the top two palm oil producers in the world and have ambitious targets to increase the palm oil-based biodiesel mandate. In Indonesia, the current programme of blending 20 per cent palm oil into 80 per cent diesel (B20) increases to B30 in 2020. Likewise, Malaysia plans to increase its biodiesel mandate from B10 to B20 in 2020. However, the outbreak of COVID-19 has infected millions and brought the global economy to a near-deadlock. The effect is particularly severe in the fuel industry owing to movement restrictions and the historic drop in oil prices. Evaluating the impact of the COVID-19 on the biodiesel industry is crucial for policymakers but challenging as the pandemic has evolved with intense speed. This article aims to discuss the impact of COVID-19 on the Indonesian and Malaysian biodiesel industry. In addition to that, a number of possible solutions to overcome the challenges were addressed and proposed. Despite severely affected by COVID-19, both Indonesia and Malaysia can use this momentum to improve and strengthen their biodiesel sector. Given its fiscal deficit, Indonesia should postpone its biodiesel blending mandate as the subsidy to support the programme can worsen the country’s financial stability. In Malaysia, where labour shortage is prevalent, modernising plantations with automated equipment, for instance, could potentially remove the dirty and dangerous stereotypes associated with plantation works, thus attracting more locals to work in the palm oil plantation and solving the labour shortage. This paper also briefly addresses the adoption of Industry 4.0 and Circular Economy for the palm oil biodiesel industry.

Homogeneous Charge Compression Ignition (HCCI) engine has attracted great attention due to its improved performance and emissions compared to conventional engines. It can reduce both Nitrogen Oxides (NOx) and Particulate Matter (PM) emissions simultaneously without sacrificing the engine performance. However, controlling its combustion phasing remains a major challenge due to the absence of direct control mechanism. The start of combustion is entirely initiated by the chemical reactions inside the combustion chamber, resulted from the compression of its homogeneous mixtures. Varying some critical engine parameters can play a significant role to control the combustion phasing of HCCI engine. This paper investigates the characteristics of HCCI combustion fuelled with n-heptane (C7H16) using single-zone model computational software. The model enabled the combustion object to vary from cycle to cycle. Detailed simulations were conducted to evaluate the effects of air fuel ratio (AFR), compression ratio (CR) and intake air temperature on the in-cylinder pressure and heat release rate. The simulation results showed that the single-zone model was able to predict the two-stage kinetic combustion of HCCI engine; the Low Temperature Heat Release (LTHR) and the High Temperature Heat Release (HTHR) regions. It was found that minor changes in AFR, CR and inlet air temperature led to major changes in the HCCI combustion phasing.

Several studies on ethanol as a biofuel have been comprehensively carried out. Today, a growing interest in longer chain alcohols has emerged due to their favourable physical and thermodynamic properties. Butanol or butyl alcohol with 4-carbon structure (C4H9OH) is a more promising biofuel as it outweighs methanol and ethanol in several ways. The production cost of butanol has been gradually reduced, and rapid progress in the development of its production technology has allowed butanol to be produced more effectively. However, studies on the effect of butanol on gasoline or spark ignition (SI) engines are not as comprehensive as the abundant research of ethanol. This paper highlights recent novelty and contribution of butanol addition in SI engine. Results of new approaches on the engine’s performance, combustion and emission characteristics are summarised. Reviews from this paper suggest that there are some gaps in the addition of butanol found in the literature. Thus, several encounters and forthcoming research directions are outlined in the final section of this review article, highlighting several possible contributions that have not yet been carried out using butanol as a biofuel in a gasoline engine.

Homogeneous Charge Compression Ignition (HCCI) is a commonly research new combustion mode due to its advantages over conventional combustion in internal combustion engine such as higher thermal efficiency as well as lower particulate matter (PM) and nitrogen oxides (NOx) emission. However, combustion phasing control difficulty is the main challenge in order to achieve this HCCI combustion due to the absence of direct auto-ignition control. The aim of this study is to investigate the effects of engine load conditions, intake charge temperature and exhaust gas recirculation (EGR) rate numerically on the combustion characteristics of HCCI engine in a single-cylinder and four-stroke engine fuelled with n-butanol. Predictive one-dimensional engine cycle simulation with single-zone model is employed in this study. A chemical kinetic mechanism of n-butanol is used to in this model to capture the chemical reaction process during the combustion. It was found that these parameters play important roles towards the combustion phasing of the HCCI engine as well as the in-cylinder pressure. This HCCI model is able to predict the trend of the combustion characteristics comprehensively with the variation of these critical parameters resulting in a good agreement with previous HCCI studies.

Reactivity controlled compression ignition has been introduced to implement controllable, clean, and high thermal efficiency without undermining the advantages of premixed combustion. However, simultaneous auto-ignition introduced by reactivity controlled combustion challenges the combustion under higher load operations. This experimental study incorporates a dual phase heat release concept with the purpose of improving the performance of reactivity controlled compression ignition engine. Different ratios of ethanol/diethyl-ether blends (from 0% to 40% diethyl ether and 70% premixed ratio) were applied to a light duty diesel engine at various combustion timings and engine loads. The diesel fuel was directly injected into the combustion chamber while ethanol/diethyl-ether blends were injected in the intake port. Engine performance and exhaust emissions were compared between the baseline operation and high blend ratios. An addition of 40% diethyl ether in the ethanol approximately resulted in 14% increase of the indicated mean effective pressure and 33% reduction in maximum pressure rise rate. The high reactivity of diethyl ether enhanced the oxidation of the hydrocarbons and resulted in lower hydrocarbon emissions. The higher volatility and better overall fuel-air mixing improved the combustion and reduced particle emission. Stable combustion was expanded at high load operating conditions due to double-stage heat release enhancement.

Reactivity Controlled Compression Ignition can be extended over a wide spectrum of fuels and is anticipated as a promising strategy in meeting current and future emission regulations. In this study, the effect of n-butanol addition on combustion characteristics and emissions in a reactivity controlled engine was investigated experimentally. Different ratios of butanol-diesel blends at different settings of EGR and premixed ratios were applied to a light duty diesel engine. The butanol-diesel blends were directly injected into the combustion chamber while gasoline was injected at the intake port. Combustion phasing was maintained at 2.7 °CA for all of test points by adjusting fuel injection timing. The results showed that start of combustion delayed by n-butanol addition, so direct injection timing should be retarded to keep constant the combustion phasing. By increasing n-butanol fraction in the mixture from 0% to 40%, the optimum value of premixed ratio has decreased from 85% to 70%. The addition of n-butanol has reduced CO emission while HC emission has increased due to higher latent heat of vaporization of the alcohol fuel. The incorporation of an EGR unit in the experimental setup has improved the engine’s thermal efficiency but of little effect on the optimum premixed fuel ratio.

Conventional two-stroke cycle engine suffers from typical drawbacks including lower combustion efficiency and excessive emissions of uHC and CO which are largely due to low in-cylinder average charge temperature at low load and speed regions of engine operating conditions. Utilising the hot burned Exhaust Gas Recirculation (EGR) technique can boost the in-cylinder average charge temperature of the engine. The influence of hot burned gases applied by means of both Internal EGR and External EGR strategies on the combustion stability and exhaust gas emission of a single-cylinder two-stroke cycle engine running at low-load and mid-load of operating conditions was investigated experimentally along with simulation works using 1-D engine simulation code. The results indicated that both In-EGR and Ex-EGR improved the combustion stability (lower misfire cycle) and decreased the concentrations of uHC and CO emissions, specifically at low speed region; however, NOx concentration was increased. At Internal EGR setting of 30%, the Coefficient of Variation for maximum in-cylinder pressure (COVPmax) reached the minimum by 5.64 while when External EGR percentage was 25%, COVPmax approached about 6.67 at the mid-speed (2000 rpm) of engine operating condition.

The comparative analysis on combustion of commercial gasoline with research octane number (RON) 95, 97, and 100 was carried out on a spark ignition (SI) engine under different engine speeds, loads and spark advances. The RON classification procedure was investigated using regression analysis and artificial neural network (ANN) by executing the combustion properties derived from the in-cylinder pressure signal and engine rotational speed signal. The results showed a special pattern for each fuel RON; these patterns were obtained using the peak in-cylinder pressure, maximum rate of pressure rise, and maximum amplitude of pressure oscillations. In addition, a pre-defined threshold or formula is necessary to restrict the implementation of these parameters for on-board fuel identification. Lastly, the confusion matrix that provided the ANN model efficiency for RON classification had the highest accuracy when the pressure signal was employed as the network input for all spark advance timing. However, the ANN model with rotational speed signal input could only identify the fuel octane number after a specific advance timing that was detected at the beginning of noisy combustion because of knock. The confusion matrix for the ANN with speed signal input increased from 68.1% to 100% when ignition advanced from −10° to −30° before top dead center. The results established the feasibility of use of the rotational speed signal as the input for an ANN model to identify different fuel octane number patterns.

Fuel cell is one of the green technologies that can help reduce toxic gas and decreasing effect of greenhouse gases in the world. This paper attempts to improve simulation model of fuel cell system that is easy to use and at the same time have an acceptable accuracy. The simulation model is developed through Matlab/Simulink software using Energetic Macroscopic Representation method which accuracy is compared with an established model. Simulation analysis of fuel cell integration is conducted by using experimental data from a real hybrid car. There are two potential types of system that were considered for the hybrid car in term of electricity generation and power produced to move the car, a full fuel cell car or a hybrid of fuel cell and battery. Analysis reveals that the hybrid car using combination of fuel cell and battery system is more effective compared to the car using fully fuel cell system due to factors that prevents fuel cell wide utilization for the vehicle.

The activity presented in this paper is focused on the relationship between mass flow rate and the intake port geometry in the cylinder head. Mass flow rate in this study refers to the amount of air-fuel mixture passing through the intake port per second (g/s). The mass flow in the intake port was studied with the help of the Ansys Workbench simulation. The intake port in the cylinder head is symmetrical. Thus, only half part is used for the simulation. During the simulation, the pressure of the air-fuel mixture applied to the intake port remained constant and the valve was held fixed ranging between 4 mm to 10 mm, as is typically done in superflow bench test. Then, the mass flow rate is recorded corresponding to the valve lifts. The simulation tests were carried out by using a HP workstation computer at Automotive Development Centre (ADC), Universiti Teknologi Malaysia. In this study, several modifications were made to the intake port geometry. Simulation is carried out using all intake ports. It was found that each intake port has its own mass flow rate value. One of the best intake ports in this study has an improvement of mass flow rate up to 7.1% at 8mm valve lift. The mass flow rate increase if air flow has a better attachment to the surface. Theoretically, the perfect intake port is completely straight. The straight and large diameter intake port is more suitable for high valve lifts.

Radiator acts as cooling system of vehicle by the air flows while the car is moving and by suction fan when the car is in stationary. In this research, vehicle cooling system test rig has been fabricated to simulate and analysis the cooling process for better air flow measurement. A flow conditioner which is wind tunnel is designed and fabricated in order to create and guide the air flow. One preliminary and two actual experiments were conducted. The preliminary experiment was carried out to select the blower. The actual experiments were performed in order to obtain the velocity distribution and data of thermal analysis. The velocity distribution and flow profile of air were being compared for the configuration without and with wind tunnel. Besides, the effectiveness of the radiator at different blower motor speeds was also plotted. The fluctuation in velocity of air has decreased with the wind tunnel. The flow profile of air with wind tunnel shows a trend of flow in the duct as compared to asymmetric flow profile without the wind tunnel. With the wind tunnel, the highest effectiveness of the radiator is 73.80% at the average air velocity of 33.78 km/h. Without the wind tunnel, the highest effectiveness of the radiator is 65.61% at average air velocity of 39.21 km/h. As a conclusion, the effectiveness of radiator has improved with the air passing through the wind tunnel before entering the radiator.

Ethanol-Diesel blended fuel is usually known as ‘E-Diesel’, ‘Diesohol’ or ‘Oxygenated Diesel’ that has been performed on the unmodified compression ignition engine. Three different proportions of 5%, 7.5% and 10% ethanol (by volume) are blended with diesel that being used as fuel. Biodiesel was added at the range of 5-10% into the blended fuels as emulsifier and balancing the overall fuel properties. Based on the properties test, it was found that the blended fuels have lower heating value, kinematic viscosity and density as the percentage of ethanol was increased. For the engine performance characteristics, no significant reduction in brake specific fuel consumption (BSFC) due to slight difference in heating values between diesel and blended fuels. The percentage deviation of brake thermal efficiency (BTE) for blended fuels from diesel were less than 4% showing the engine converted the chemical energy in fuels into mechanical energy almost the same efficiency. Whilst for emissions, the blended fuels reduced in oxides of nitrogen (NOX) at the range of 24.1-43.1% compared to diesel. As conclusion, the best blended fuel is E5 which contained 5% ethanol, 7.5% biodiesel and 87.5% diesel (D87.5B7.5E5) that contributed lower NOX emitted and performed better in term of BSFC and BTE.

A high concentration of palm oil biodiesel fuel blend is a strong candidate to substitute conventional diesel fuel (B10) due to its prospect to release fewer emissions. This paper shall present findings when testing palm oil biodiesel fuel blends (B10, B20, and B30) at medium speed (2500 rpm) in a single-cylinder Yanmar L70N diesel engine coupled to an eddy current dynamometer. In this study, a timed burette and an airbox determined the engine’s fuel and air consumption, respectively. In contrast, a flue gas analyzer measured the emission released by the fuel blend. The result indicates that as the concentration of palm oil biodiesel increases in the blends (from B10 to B30), there is no significant difference (average less than 5%) between the fuel blends in terms of brake thermal efficiency, brake specific fuel consumption, and air-fuel ratio. On the other hand, the emission results showed a reduction in CO, CO2, and NOx when the concentration of palm oil biodiesel increases in the blends. Considering the fuel blend would have no significant difference in the engine performance and its ability to reduce most emission, it is safe to conclude that B30 would be a good alternative for current diesel fuel (B10).

Butanol offers more promising results compared to lower carbon alcohol. Yet, it has not been commercially produced as a biofuel due to its expensive recovery process from Acetone-Butanol-Ethanol (ABE) fermentation. If ABE is used directly as a biofuel, the process will be more straightforward, thus eliminating its energy and cost-intensive purification process. Study on ABE as a biofuel has become a growing field for the last five years. Several preliminary studies have reported convincing results of using ABE-diesel blends in diesel engines. However, many of the studies on ABE lacks clarity regarding its fuel properties. In fact, no previous study has investigated the fuel properties of ABE. Therefore, this study aims to quantify some critical physico-chemical properties of ABE-diesel blends. Several important fuel properties were investigated in this study; calorific value, density, kinematic viscosity, distillation characteristics and cetane index. In terms of blending strategy, results from this study indicate that ABE(3 6 1) can be added up to 42% to diesel fuel, while ABE(6 3 1) and ABE(1 3 6) can only be added up to 22% and 23%, respectively. Also, the mathematical correlations to estimate ABE’s fuel properties are presented. The equations developed in this study gave have high coefficient of determination values. They can serve as prediction models for future studies. Considering its relatively low-cost production and satisfying physico-chemical properties, ABE has the potential to become a promising alternative biofuel.

The performance of Spark Ignition (SI) engines in terms of thermal efficiency can be restricted by knock. Although it is common for all SI engines to exhibit knock from compressed end-gas, knocks from surface ignition remains a more serious problem due to its effect on combustion stability and its obscurity to detect. This paper focuses on predicting the occurrence of knocks from surface ignition by monitoring exhaust gas temperature (EGT). EGT measured during an engine cycle without the spark plug firing. Therefore, EGT rises illustrated any combustion made by surface ignition. Modelling and simulation of a one-dimensional engine combustion done by using GT-Power. The new approach reduces the complexity as EGT monitoring does not require high computational demands, and the EGT signals are robust to noise. The method is validated against a variety of fuel properties and across engine conditions. A new approach is proposed as a measure to predict and detect the knock events.

There are many technologies that being developed to increase the efficiency of internal combustion engines as well as reducing their fuel consumption. In this paper, the main research area is focus on cylinder deactivation (CDA) technology. CDA mostly being applied on multi cylinders engines. CDA has the advantage in improving fuel consumption by reducing pumping losses at part load engine conditions. Here, the application of CDA on 1.6L four cylinders gasoline engine was studied. One-dimensional (1D) engine modeling is performed to investigate the effect of intake valve strategy on engine performance with CDA. 1D engine model is constructed according to the 1.6L actual engine geometries. The model is simulated at various engine speeds at full load conditions. The simulated results show that the constructed model is well correlated to measured data. This correlated model used to investigate the CDA application at part load conditions. Also, the effects on the in-cylinder combustion as well as pumping losses are presented. The study shows that the effect of intake valve strategy is very significant on engine performance. Pumping losses is found to be reduced, thus improving fuel consumption and engine efficiency.

In automotive engine applications, the spark ignition (SI) engines can operate at various engine speed and load conditions. However, most of the time was spend at part load operations, where they operate below their rated output especially during cruising or idling. The needs of improvement in term of engine efficiency at part load operation become more popular among the engine manufacturers. One of the main reasons for efficiency dropped at part load conditions is the flow restrictions at the throttle valve opening area due to nearly-close position to control amount of inducted air into the cylinder, which leads to increasing in pumping losses. Hence, there are a lot of studies and investigations have been carried out to tackle these problems without sacrificing the original performance. This paper will investigate further the engine efficiency, performance as well as fuel economy by using one-dimensional (1-D) simulation tool. A baseline simulation model of a 1.6 liters four cylinders, port fuel injection engine has been developed based on the actual engine geometries. This baseline model applied predictive combustion to predict the amount of cylinder pressure based on actual ignition and injection timing on bench. The simulated results show a very good agreement with the measured data. Additionally, this study also proved that the deactivation half of the cylinders can significantly reduce the pumping losses of fired cylinder while eliminated the pumping work of unfired cylinders.

Battery Electric Vehicles (BEVs) is a promising technology. However, it suffers from low range characteristics thus increasing the anxiety to prospect customers and hindering its market penetration. To overcome this challenge, a range extender that can generate additional power to charge the battery could be the solution. This brief review article will highlight the prospects and challenges of range extender technology for electric vehicles. A number of automobile manufacturers have launched their Range Extended Electric Vehicles (REEVs) models and the detailed comparison will be given. Several types of range extenders will be discussed, including the internal combustion engine, microturbine, and fuel cell. Lastly, this report will suggest the use of Low Temperature Combustion (LTC) i.e Homogeneous Charge Compression Ignition (HCCI) engine be utilised as range extenders for electric vehicles.

This research aims to design and develop a data monitoring and acquisition system of an onboard and wireless data telemetry system for electric vehicle. The scopes of this research are sensor integrations (6DOF IMU sensor and voltage sensor), creating a Graphical User Interface (GUI) for onboard monitoring system, conducting tests on data acquired by systems and connection’s durability testing for the developed systems. The onboard system consists of Arduino Uno, sensors, a serial communication module, LCD display and a memory card which is fitted onto RC car for data recording. The data is transmitted to the wireless system via radio frequency through the serial communication module. The wireless system consisting of Arduino Uno and a serial communication module are connected to a laptop. The data collected from both systems are compared to ensure minimal data losses. It is found that there are no data losses between the data transmitted and received. As an outcome from this research, a telemetry system has been developed to be used on RC cars.

A muffler is a device to attenuate noise from the exhaust. The muffler performance determined by the acoustic performance is called sound transmission loss (STL). This paper aims to measure the STL experimentally and correlated with the 1D simulation result. STL was measured using the impedance tube. Four-pole method (microphone) and two-load method were applied to measure the STL. The STL was also determined through the 1D simulation tools software. Three types of mufflers STL were measured; small expansion chamber, big expansion chamber and complex muffler. The respective error between simulation and experiment were 0.17%, 7.89%, and 11.40%. Hence, the STL experiment result was well correlated with the 1D simulation model.

In this paper a full electric all-terrain vehicle (ATV) owned by the automotive laboratory of Universiti Teknologi Malaysia is converted into a series hybrid electric vehicle (HEV) with a range extender. Before the transformation, it is required to predetermine the amount of power that should be used to extend the autonomy of the battery. Experiments are conducted to define the vehicle parameters and characteristics for the development of the simulation model. By using the developed model, simulations are conducted by considering NEDC cycle for a work-commuter who wants to use a vehicle 5 hours per week (30 min one way) without having to charge the battery. It is assumed that the battery is charged at the beginning of the week and must not be discharged under 0.2 state of charge (SOC) for safety reasons. Two control strategies are considered to obtain this objective; the always on engine and the delayed use of the engine. After simulation both controls use the same amount of fuel. As conclusion, the addition of the engine is proven to be effective in prolonging the distance range of the vehicle.

Combustion with knock is an abnormal phenomenon which constrains the engine performance, thermal efficiency and longevity. The advance timing of the ignition system requires it to be updated with respect to fuel octane number variation. The production series engines are calibrated by the manufacturer to run with a special fuel octane number. In the experiment, the engine was operated at different speeds, loads, spark advance timings and consumed commercial gasoline with research octane numbers (RON) 95, 97 and 100. A 1-dimensional validated engine combustion model was run in the GT-Power software to simulate the engine conditions required to define the knock envelope at the same engine operation conditions as experiment. The knock intensity investigation due to spark advance sweep shows that combustion with noise was started after a specific advance ignition timing and the audible knock occur by increasing the advance timing. Therefore, the engine operation was divided into three regions; knock-free, light knock and heavy knock. The results for heavy-knock were well suited to audible knock detected by knock sensor. The simulation results from knock model divide the engine operation into two regions; normal combustion and knock region. The knock region was well suited to light-knock and heavy-knock which has been defined using experimental results. Next, an artificial neural network (ANN) model has been designed to classify the different RONs using engine rotational speed signal. The model classified different RONs accurately after starting point of noisy combustion (light-knock). This point defined from experimental results and was well suited with starting point of knock index increment from simulation results. The simulation tool ability to predict the knock envelope will reduce the experimental cost and time to generate the spark timing look-up table.

Lower temperature biohydrogen production has always been attractive, due to the lower energy requirements. However, the slow metabolic rate of psychrotolerant biohydrogen-producing bacteria is a common problem that affects their biohydrogen yield. This study reports on the improved substrate synthesis and biohydrogen productivity by the psychrotolerant Klebsiella sp. strain ABZ11, isolated from Antarctic seawater sample. The isolate was screened for biohydrogen production at 30°C, under facultative anaerobic condition. The isolate is able to ferment glucose, fructose and sucrose with biohydrogen production rate and yield of 0.8 mol/l/h and 3.8 mol/g, respectively at 10 g/l glucose concentration. It also showed 74% carbohydrate uptake and 95% oxygen uptake ability, and a wide growth temperature range with optimum at 37°C. Klebsiella sp. ABZ11 has a short biohydrogen production lag phase, fast substrate uptake and is able to tolerate the presence of oxygen in the culture medium. Thus, the isolate has a potential to be used for lower temperature biohydrogen production process.