17 research outputs found
Experimental investigation into the physico-chemical properties changes of palm biodiesel under common rail diesel engine operation for the elucidation of metal corrosion and elastomer degradation in fuel delivery system
Compatibility of fuel delivery materials (FDM) with biodiesel fuel in the fuel delivery system (FDS) under real-life common rail diesel engine (CRDE) operation poses a challenge to researchers and engine manufacturers alike. Although standard methods such as ASTM G31 and ASTM D471 for metals and elastomers, respectively, are deemed suitable for evaluating the effects of water content, total acid number (TAN) and oxidation products in biodiesel on FDM degradation, they do not resemble the actual engine operation conditions such as varying fuel pressure/temperature as well as the presence of a wide range of materials in the FDS of a diesel engine. Hence, the current allowable maximum 20 vol% of biodiesel with 80 vol% of diesel (B20) for use in diesel engines to date is debatable. Additionally, biodiesel utilization beyond B20 is essential to combat declining air quality and to reduce the dependence on fuel imports. This thesis aims to elucidate the actual compatibility present between FDM and biodiesel in the FDS under real-life CRDE operation. This was achieved through multi-faceted experimentations which commenced with analyses on the deteriorated palm biodiesel samples collected during and after CRDE operation. Next, the fuel properties which should be emphasized based on the deteriorated fuel were determined. This was then followed by ascertaining the effects of the emphasized fuel properties towards FDM degradation. Ultimately, the actual compatibility of FDM with biodiesel under engine operation through modified immersion investigations was determined. FDM degradation acceleration factors such as oxidized biodiesel, TAN and water content were eliminated since these factors were not affected based on the analysed fuel samples collected after engine operation. No oxidation products such as aldehydes, ketones and carboxylic acids were detected while the TAN and water content were within 0.446% and 0.625% of their initial values, respectively. Instead, the biodiesel’s dissolved oxygen (DO) concentration and conductivity value were not only found to have changed during and after engine operation by -93% and 293%, respectively, but were also found to have influenced biodiesel deterioration under engine operation. These two properties were subsequently discovered to have adversely affected FDM degradation independently. The copper corrosion rate and nitrile rubber (NBR) volume change increased by 9% and 13%, respectively, due to 22% increase in the conductivity value. In contrast, the copper corrosion rate and NBR volume swelling reduced by 91% and 27%, respectively, due to 96% reduction in the DO concentration. Ultimately, copper corrosion and NBR degradation were determined to be lowered by up to 92% and 73%, respectively, under modified immersion as compared to typical immersion condition. These outcomes distinctly show that acceptable to good compatibility is present between FDM and biodiesel under CRDE operation. The good compatibility is strongly supported since only a maximum lifespan reduction of 1.5 years is predicted for metal exposed to biodiesel as compared to diesel for a typical component lifespan of 15 years. For the elastomers, acceptable compatibility is found present between elastomer and biodiesel based on the determined 11% volume change which conforms to the tolerance level of elastomer degradation as stated by the elastomer manufacturers. These are especially true for the evaluated metals and elastomers investigated under the modified laboratory immersion which replicates similar conditions to a real-life CRDE. Overall, this work has contributed to the advancement of knowledge and application of biodiesel use in diesel engines
Experimental investigation into the physico-chemical properties changes of palm biodiesel under common rail diesel engine operation for the elucidation of metal corrosion and elastomer degradation in fuel delivery system
Compatibility of fuel delivery materials (FDM) with biodiesel fuel in the fuel delivery system (FDS) under real-life common rail diesel engine (CRDE) operation poses a challenge to researchers and engine manufacturers alike. Although standard methods such as ASTM G31 and ASTM D471 for metals and elastomers, respectively, are deemed suitable for evaluating the effects of water content, total acid number (TAN) and oxidation products in biodiesel on FDM degradation, they do not resemble the actual engine operation conditions such as varying fuel pressure/temperature as well as the presence of a wide range of materials in the FDS of a diesel engine. Hence, the current allowable maximum 20 vol% of biodiesel with 80 vol% of diesel (B20) for use in diesel engines to date is debatable. Additionally, biodiesel utilization beyond B20 is essential to combat declining air quality and to reduce the dependence on fuel imports. This thesis aims to elucidate the actual compatibility present between FDM and biodiesel in the FDS under real-life CRDE operation. This was achieved through multi-faceted experimentations which commenced with analyses on the deteriorated palm biodiesel samples collected during and after CRDE operation. Next, the fuel properties which should be emphasized based on the deteriorated fuel were determined. This was then followed by ascertaining the effects of the emphasized fuel properties towards FDM degradation. Ultimately, the actual compatibility of FDM with biodiesel under engine operation through modified immersion investigations was determined. FDM degradation acceleration factors such as oxidized biodiesel, TAN and water content were eliminated since these factors were not affected based on the analysed fuel samples collected after engine operation. No oxidation products such as aldehydes, ketones and carboxylic acids were detected while the TAN and water content were within 0.446% and 0.625% of their initial values, respectively. Instead, the biodiesel’s dissolved oxygen (DO) concentration and conductivity value were not only found to have changed during and after engine operation by -93% and 293%, respectively, but were also found to have influenced biodiesel deterioration under engine operation. These two properties were subsequently discovered to have adversely affected FDM degradation independently. The copper corrosion rate and nitrile rubber (NBR) volume change increased by 9% and 13%, respectively, due to 22% increase in the conductivity value. In contrast, the copper corrosion rate and NBR volume swelling reduced by 91% and 27%, respectively, due to 96% reduction in the DO concentration. Ultimately, copper corrosion and NBR degradation were determined to be lowered by up to 92% and 73%, respectively, under modified immersion as compared to typical immersion condition. These outcomes distinctly show that acceptable to good compatibility is present between FDM and biodiesel under CRDE operation. The good compatibility is strongly supported since only a maximum lifespan reduction of 1.5 years is predicted for metal exposed to biodiesel as compared to diesel for a typical component lifespan of 15 years. For the elastomers, acceptable compatibility is found present between elastomer and biodiesel based on the determined 11% volume change which conforms to the tolerance level of elastomer degradation as stated by the elastomer manufacturers. These are especially true for the evaluated metals and elastomers investigated under the modified laboratory immersion which replicates similar conditions to a real-life CRDE. Overall, this work has contributed to the advancement of knowledge and application of biodiesel use in diesel engines
The suitability of fly ash based geopolymer cement for oil well cementing applications: A review
The increase in awareness towards global warming has prompted the research of alternatives to the conventional
ordinary Portland Cement (OPC). In addition, studies have demonstrated that the use of geopolymer cement slurries
resulted in lower carbon emission and superior cement properties compared to the ordinary Portland cement. In this study, the factors which affect the wellbore integrity in regards to cementing were identified and a comparison between Class G cement and Fly Ash Geopolymer (FAGP) cement pertaining to the identified factors were made. In addition, a thorough analysis on the factors affecting the properties of geopolymer in regards to its application in oil well cementing was performed. The results enable the finding of optimum parameters required to produce geopolymer cements for oil well applications. The FAGP cement achieved higher compressive strengths compared to Class G cement for all curing temperatures above 36⁰C. At optimum curing temperatures, for all curing time FAGP cement achieved higher compressive strengths in comparison Class G cement. Moreover, FAGP cement was found to be more susceptible to marine environment whereby curing medium of brine water resulted in higher compressive strengths. In addition, FAGP cement has lesser carbon footprint, superior chemical durability, lower permeability and higher crack propagation threshold in comparison the Class G cement. In addition, key variables which influence the compressive strength of FAGP cement such as type of activating solution, concentration of activating solution alkaline liquid to fly ash ratio, aging duration and water to binder ratio were identified and the corresponding optimum values in achieving highest compressive strength were suggested. The conclusion supports the usage of geopolymer cement for oil well cementing whereby it has an edge over conventional Portland cement for better short term and long term performance to ensure wellbore integrity throughout the producing life span of the well, with less hazards imposed on the environment
Optimization of palm oil in water nano-emulsion with curcumin using microfluidizer and response surface methodology
This study aims to produce and optimize palm oil-based nano-emulsion to encapsulate curcumin using microfluidizer and Response Surface Methodology (RSM). Encapsulation of curcumin is essential to overcome curcumin's poor bioavailability through the formation of nano-sized droplets in order to harvest its outstanding anti-inflammatory and anti-cancer medicinal properties. Among the parameters of concern are microfluidizer's pressure, number of cycles and surfactant concentration (Tween 80). Optimisations were performed by employing RSM. Characterisations were conducted for the droplet size, poly-dispersity index (PDI), zeta potential (ZP) and viscosity. Stable palm oil-based oil in water nano-emulsion encapsulating curcumin was achieved at a droplet size of 275.5 nm, PDI of 0.257, ZP of −36.2 and viscosity of 446 cP using microfluidizer. The optimized conditions were at 350 bar, 5 cycles and 1 wt% surfactant. Optimized microfluidizer with the aid of RSM is deemed capable to produce palm oil-based oil in water nano-emulsion encapsulating curcumin with small droplet size using low surfactant concentration and under optimum energy consumption
Review of nano piezoelectric devices in biomedicine applications
The piezoelectric devices, based on micro–nano electromechanical systems, are well known nowadays due to their small features, ability for integration with the integrated circuit in a single platform, robust, and easily fabricated in bulk. The enhanced performance of piezoelectric systems, which is soft, flexible, and stretchable made them have unique opportunities to be used in bio-integrated applications as nanodevices for energy harvesting, sensing, actuation, and cell stimulation. The selection of optimized configurations depends on thin geometries, neutral mechanical plane construction, and controlled buckling, while inorganic piezoelectric materials are preferred for interfaces with human bodies. The key considerations in designs, the analytical derivations for voltage and displacement, and the effect of the voltmeter resistance on the voltage measurements are presented. Devices for energy harvesting from natural motions of internal organs, sensors, and actuators for medical applications are reviewed. The PMN-PT energy harvester that produced current of 0.22 mA is higher than the rest of the discussed harvesters. Thus, it is more suitable to be used as a sufficient source of energy in biomedical applications. The use of piezoelectric nanowires and ribbons proved successful, and the dual features of device (sensor and actuator) seem advantageo
Characterization and optimization of waste-derived biodiesel utilizing CNT/MgO nanocomposite and water emulsion for enhanced performance and emission metrics
Efficiently managing agricultural plant residues is a growing concern, leading to a focus on converting waste materials into valuable resources. The Rutaceae family, especially Citrus maxima peel oil (CMPO), has potential for biofuel production, but research on its use remains limited, especially in terms of fuel modification. This study aims to extract biofuel from Citrus maxima peel and characterize its chemical components. To enhance efficiency and align with environmental goals, the study suggests integrating water and a nanocomposite into CMPO. An eco-friendly method was employed to synthesize a carbon nanotube (CNT)-induced magnesium oxide (MgO) nanocomposite that was extensively characterized. Fuel combinations were derived using a Box-Behnken design matrix, and optimization followed, emphasizing performance and emission parameters. Analysis of the elemental composition and free fatty acid profile of extracted CMPO highlights its potential as an alternative fuel. Optimal concentrations of CMPO, water, and nanocomposite in diesel fuel were found to be 27.6%, 12.2%, and 64.9 ppm, respectively. Confirmation tests validated improved performance and emission outcomes under these optimal conditions. Projected performance and emission parameters closely align with experimental findings. The proposed fuel combination is expected to achieve a significant 40% reduction in the demand for petroleum derivatives
Critical relationship between biodiesel fuel properties and degradation of fuel delivery materials of a diesel engine
This work aims to disseminate the critical relationship present between biodiesel fuel properties and the degradation of commonly present fuel delivery materials (FDM) of a diesel engine. This was achieved by quantifying the adverse effects of palm biodiesel fuel exposure towards aluminium, galvanized steel, stainless steel, fluoroelastomer, silicone rubber and nylon under novel immersion method. Under the novel immersion method which was designed to resemble the biodiesel fuel deterioration under diesel engine operation, fuel renewal was incorporatedinthetypicalstandardmethods.Theutilizedfuelrenewaldurationswere108hand192hformetal and elastomers, respectively. Through this, the resulting biodiesel fuel properties under diesel engine operation were primarily simulated under the immersion methods. The experimentations were carried out for 540h and 960h for metals and elastomers, respectively, at 100°C. Based on the obtained results, as well as the comparisons madetoanexistingstudy, galvanizedsteel,aluminium andstainlesssteel hadlowercorrosionrateby33%, 74% and 80%, respectively, as compared to copper. On the other hand, 26%, 78% and 106% lower volume changes were determined for silicone rubber, fluoroelastomer and nylon, respectively, as compared to nitrile rubber. Significantly lower degradation rate of up to 20 times for metals and 5 times for elastomers were critically obtained under novel immersion method as compared to under typical immersion methods from existing studies. This demonstrates that through the employment of novel immersion method which simulates biodiesel fuel properties as per under diesel engine operation, much better compatibility is deemed present between biodiesel fuel and FDM contrasting to the existing studies
Enhancing automotive cooling systems: composite fins and nanoparticles analysis in radiators
Abstract Composites are driving positive developments in the automobile sector. In this study investigated the use of composite fins in radiators using computational fluid dynamics (CFD) to analyze the fluid-flow phenomenon of nanoparticles and hydrogen gas. Our world is rapidly transforming, and new technologies are leading to positive revolutions in today’s society. In this study successfully analyzed the entire thermal simulation processes of the radiator, as well as the composite fin arrangements with stress efficiency rates. The study examined the velocity path, pressure variations, and temperature distribution in the radiator setup. As found that nanoparticles and composite fins provide superior thermal heat rates and results. The combination of an aluminum radiator and composite fins in future models will support the control of cooling systems in automotive applications. The final investigation statement showed a 12% improvement with nanoparticles, where the velocity was 1.61 m/s and the radiator system’s pressure volume was 2.44 MPa. In the fin condition, the stress rate was 3.60 N/mm2
Corrosion of copper exposed to water-in biodiesel-diesel emulsion fuel stabilized with polyglycerol polyricinoleate emulsifier
Despite emulsification of water in-diesel can decrease harmful exhaust emissions, unstable emulsion can result in formation of free water which can accelerate metal corrosion in the fuel delivery system of a diesel engine. This study aimed to formulate and assess stability of 5 vol% water in 5 vol% biodiesel in diesel emulsion fuel (W5B5) and investigate its effects towards copper corrosion. Stable W5B5 was successfully prepared with 3 vol% polyglycerol polyricinoleate (PGPR). After 1200 h of storage, W5B5 remained stable, indicated by mean droplet diameter of 627.6 ± 7.5 nm, sedimentation index of ∼3 %, and absence of free water formation. Upon exposure to copper, mean droplet diameter of W5B5 increased by 2.7 times compared to prepared W5B5. Viscosity and total acid number (TAN) values of copper exposed W5B5 increased by 26 % and 270 %, respectively, indicating enlargement of water droplets and degradation of fuel during immersion. Corrosion rate of copper exposed to W5B5 decreased by 92 % between 240 and 1200 h of immersion. Corrosion rate of copper in W5B5 was 5.5 times and 3.0 times higher diesel and biodiesel, respectively. Higher initial TAN of W5B5 than other fuels, attributed to addition of PGPR to form stable water-fuel emulsion, influenced the higher corrosion rate observed in W5B5 compared to other fuels. To minimize corrosive nature of W5B5, future research should focus on developing stable formulation with low initial acidity value comparable to or even lower than biodiesel. The contribution to knowledge from the study yielded valuable insights into the stability of emulsion fuel, corrosion behaviour, and impact of emulsifier acidity on corrosion rates