Decreased Carbon Monoxide Research Articles

Influence of Simarouba Glauca (Laxmi taru) biodiesel on engine performance and emissions of conventional compression ignition engine

The present paper reports the performance and emission studies for a four stroke single cylinder CI-DI unmodified engine using laxmi taru biodiesel as fuel. Laxmi taru biodiesel has 80% potential of extracting oil from the seeds as compared to other biofuels. The properties of laxmi taru biodiesel fuel nearly match the properties of diesel fuel. In this paper performance and emission tests are conducted for different blends such as S0 (0% laxmi taru + 100% diesel), S5, S10, S20, S40 by volume. At full load conditions (4.9 kW) brake thermal efficiency (BTE) decreased for S5, S10, S20 and S40 blends by 3.26%, 4.53%, 3.16% and 5.54% respectively as compared to diesel fuel operation because of poor heating value of laxmi taru biodiesel. Presence of oxygen content in the fuel and better combustion leads to decreased carbon monoxide (CO) emission for S5, S10, S20 and S40 blends by 4%, 8%, 12% and 28% as that of diesel. Similarly hydrocarbon (HC) emission reduced by 16.21%, 24.32% and 29.7% in S10, S20 and S40 blends respectively. Oxides of Nitrogen (NOx) emission increased by 27.19%, 30.57%, 15.2% and 19.3% for S5, S10, S20 and S40 blends respectively in comparison with diesel fuel, under full load conditions due to high incylinder temperature. Usage of laxmi taru biodiesel in CI engines resulting in drastic reduction in carbon based (CO, HC) emissions without altering the performance of the engine. Therefore laxmi taru biodiesel is better alternate fuel for CI engines.

Combined influence of compression ratio and exhaust gas recirculation on the diverse characteristics of the diesel engine fueled with novel palmyra biodiesel blend

The current study investigates the influence of compression ratio and EGR on the various characteristics of diesel engine operated with 20% Palmyra oil methyl ester (POME 20) blend at different load conditions. Transesterification process is used to produce the palmyra oil methyl ester from the palmyra crude oil, which is extracted from the palmyra seeds by the application of mechanical pressing operation. ASTM standards have been used to determine the physico-chemical characteristics of palmyra oil methyl ester and these properties are close competing with the diesel fuel. Preliminary tests are conducted with blends of palmyra oil methyl ester (POME 10, POME 20 and POME 30) on diesel engine working at standard conditions and it is found improved engine performance and reduced emissions for POME20. One of the viable techniques to enhance the engine characteristics is to change the operating parameters. In this context, the present work focuses on the influences of distinct compression ratios (16:1, 18:1 and 20:1) on the diverse characteristics of diesel engine fuelled with POME 20 blend. The experimental test findings indicate that the brake thermal efficiency is enhanced by 6.91% and BSFC is lowered by 10.2%; and considerable decreases in carbon monoxide, unburned hydrocarbons, and smoke opacity emissions by 13.33%, 8.82% and 8.2% respectively found at compression ratio 20:1 when compared to POME 20 operated at compression ratio 16:1. However, the NO x emissions are found to be higher. EGR is the simplest, cheapest and most effective technique used for reduction of NO x emissions for diesel and biodiesel fuelled diesel engine. In this, EGR is added 5% and 10% rates to the POME 20 operated at 20:1 compression ratio. The test results revealed that the addition of 10% EGR to the POME 20 is found 23% reduction of NO X emissions when compared to POME 20 operated at standard operating conditions.

Studies on Biosmotrap: A multipurpose biological air purifier to minimize indoor and outdoor air pollution

Air pollution is a serious health concern that affects many people across the globe. The major air pollutants are particulate matter, carbon oxides, nitrogen oxides, sulphur oxides, volatile organic compounds, polycyclic aromatics and free radicals which cause severe respiratory distress and infections. The existing air cleaning systems suffer from drawbacks of high cost and generation of secondary pollutants. A novel biological air filter “Biosmotrap” which is a laminate composite of sponge gourd and algae was developed. Biosmotrap placed in a carrier assembly on exhaust of vehicles, could remove carbon monoxide, nitric oxide, nitrogen dioxide, and fine particulate matter (PM2.5) from the vehicular emissions resulting in cleaner emissions. Biosmotrap decreased carbon monoxide from 1,423,992 μg/m3 to 76,756 μg/m3, nitric oxide from 71,128 μg/m3 to 9982 μg/m3, nitrogen dioxide from 565 μg/m3 to 188 μg/m3 and PM2.5 from 3200 μg/m3 to 60 μg/m3 from a polluting vehicle. Biosmotrap removed 60–80% of indoor pollutants from cigarette smoke and incense-stick smoke. Biosmotrap could protect the human cells from oxidative DNA damage induced by indoor air pollutants. Hibiscus rosa-sinensis plants exposed to air filtered through Biosmotrap were healthy as compared to the plants directly exposed to polluted air. Biosmotrap is an economic, efficient, eco-friendly filter that is superior to existing air filtration methods.

New seasonal pattern of pollution emerges from changing North American wildfires

Rising emissions from wildfires over recent decades in the Pacific Northwest are known to counteract the reductions in human-produced aerosol pollution over North America. Since amplified Pacific Northwest wildfires are predicted under accelerating climate change, it is essential to understand both local and transported contributions to air pollution in North America. Here, we find corresponding increases for carbon monoxide emitted from the Pacific Northwest wildfires and observe significant impacts on both local and down-wind air pollution. Between 2002 and 2018, the Pacific Northwest atmospheric carbon monoxide abundance increased in August, while other months showed decreasing carbon monoxide, so modifying the seasonal pattern. These seasonal pattern changes extend over large regions of North America, to the Central USA and Northeast North America regions, indicating that transported wildfire pollution could potentially impact the health of millions of people.

Spray Behavior, Combustion, and Emission Characteristics of Jet Propellant-5 and Biodiesel Fuels with Multiple Split Injection Strategies

This study focuses on an analysis of the spray behavior, combustion, and emission characteristics of jet propellant-5 (JP-5) and biodiesel fuels with single-injection timing and multiple split injection strategies in a common rail direct injection (CRDI) single-cylinder diesel engine system. The analysis includes visualization of the spray and combustion. Multiple split injection strategies (e.g., double, triple, quadruple, and quintuple) were considered by equally distributing the fuel injection amount within the single-injection. Injection of biodiesel has a delayed start (0.2 ms) as well as shorter spray tip penetration compared with JP-5. As the fuel injection timing was approached to the top dead center (TDC), the engine performance and combustion efficiency improved. Retarding the injection timing contributed to an increase in carbon dioxide (CO2) (JP-5: max. 2.6% up, BD100: max. 1.5% up) and a decrease in carbon monoxide (CO) (JP-5: max. 93% down, BD100: max. 91% down) and nitrogen oxides (NOx) (JP-5: max. 83% down, BD100: max. 82% down). In comparison with JP-5, biodiesel showed disadvantages from the point of its combustion and emission characteristics for all injection timings. The quadruple-injection strategy, in which fuel injection was performed four times, showed excellent combustion, engine performance, and combustion efficiency. The CO2 emissions were highest with the quadruple-injection strategy (JP-5: 6.6%, BD100: 5.8%). The CO emissions of biodiesel decreased as the pulses of split injection extended, and a significant reduction of 83.8% was observed. NOx increased as the number of split injections increased (JP-5: max. 37% up, BD100: max. 52% up). JP-5 was a longer ignition delay than that of biodiesel from combustion flame visualization results. The final combustion in the multiple-injection strategy showed a typical diffusion combustion pattern.

Energy recovery of waste plastics into diesel fuel with ethanol and ethoxy ethyl acetate additives on circular economy strategy

The widespread use of plastic goods creates huge disposal issues and environmental concerns. Increasing emphasis has been paid to the notion of a circular economy, which might have a significant impact on the demand for plastic raw materials. Post-consumer plastics recycling is a major focus of the nation’s circular economy. This study focuses on energy recovery from waste plastics as an alternative fuel source to meet the circular economy demand. Waste plastic fuel produced through pyrolysis has been claimed to be utilized as a substituted fuel. This work focuses to determine the performance and emission standards of Waste Plastic Fuel (WPF) generated from the pyrolysis of High-Density Polyethylene (HDPE) in a single-cylinder Direct Injection Diesel Engine (DIDE). Three different ratios of WPF were combined with 10% ethanol and 10% ethoxy ethyl acetate as an oxygenated additive to create quaternary fuel blends. The ethanol has a low viscosity, a high oxygen content, a high hydrogen-to-carbon ratio as favourable properties, the quaternary fuel results the improved brake thermal efficiency, fuel consumption and reduced emissions. The blend WEE20 exhibits 4.7% higher brake thermal efficiency, and 7.8% reduced fuel consumption compared to the diesel. The quaternary fuel blends demonstrated decreased carbon monoxide of 3.7 to 13.4% and reduced hydrocarbons of 2 to 16% under different load conditions.

Platelet-to-Lymphocyte Ratio as an Indicator to Predict Decreased Carbon Monoxide Diffusion of the Lung in Patients with Testicular Cancer.

To investigate whether the use of diffusing capacity of the lungs for carbon monoxide (DLCO) and neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) could be used to predict bleomycin-induced pulmonary toxicity in patients with testicular cancer (TCa). Descriptive study. Ankara Oncology Training and Research Hospital, Turkey, between 2017 and 2020. Data of 40 patients with TCa, who were followed at cancer centre from 2017-2020 and received 3-4 cycles of BEP protocol were retrospectively screened and included who met the criteria for inclusion in the study. All patients with TCa, who were older than 18 years of age and had no secondary malignancy and comorbidity, were included in this study. A statistically significant negative correlation was found between DLCO change and NLR, PLR (r:-0.558, p:0.002 for NLR; r:-0.462 p:0.012 for PLR). A statistically significant positive correlation was found between DLCO change and lymphocyte level (r:0.436, p:0.018). The NLR and PLR were statistically higher in the group with a decrease of ≥10% in DLCO compared to the group with no decrease or a decrease of ≤10% in DLCO (for NLR; 3.03 ± 1.45 and 1.68 ± 0.73, respectively, p = 0.005; for PLR 187.72 ± 66.90 and 124.72 ± 47.99, respectively, p = 0.008). Multivariate regression analysis showed a statistically significant relationship between PLR increase and a decrease of ≥10% in DLCO. PLR and LDH could be used as independent predictive biomarkers for DLCO decline which is used to identify bleomycin-induced pulmonary toxicity. Key Words: Bleomycin, Markers of inflammation, Platelet-to-lymphocyte ratio (PLR), Pulmonary diffusing capacity, Testicular cancer.

Improving Household Safety via a Dynamic Air Terminal Device in Order to Decrease Carbon Monoxide Migration from a Gas Furnace.

The airtightness of buildings is continuing to grow and impact the indoor environment. Its aim is to conserve energy, but this may influence the indoor air quality and increase contaminant accumulation by limiting the amount of fresh air that infiltrates the building. The goal of this study was to quantify how the contaminants from a faulty gas furnace in a household could impact the occupants. The gas furnace was located in an attached garage and leaked carbon monoxide (CO). Multizone and CFD simulations were caried out to determine if an air terminal device (ATD) with a changing geometry could improve the air quality. The goal of the ATD was to maintain a steady air throw in the garage, while the air flow in the ventilation system would change. A steady air throw should help to remove the carbon monoxide generated from the furnace and prevent infiltration into the household. The results show that with the use of the new ATD, it was possible to maintain a steady air throw and the infiltration of CO was lowered.

Benzin-metanol (M5-M10) karışımlarının SI motorundaki performans üzerine deneysel bir araştırması

Methanol is one of the promising alternative fuels for spark-ignition engines. It has a high octane number, increasing the octane number of gasoline that influence engine setting parameters. Ignition timing and injection duration are two engine setting parameters that influence the combustion process and emission of spark-ignition engine, which are therefore fascinating to be studied. The main objective of this work was to improve the performance of gasoline-methanol blends in a spark-ignition engine, which was carried out by optimization of engine operational parameters, which were ignition timing and injection duration. Performance parameters measured in this study were engine torque, power, and specific fuel consumption. An emission parameter such as carbon dioxide, carbon monoxide, and unburnt hydrocarbons was measured to evaluate the combustion process. Test results were analyzed by comparing performance and emission parameters of the engine on its standard and optimized settings. The result obtained that optimized ignition timing and injection duration sets products in an increase in engine torque and power, which are up to 12.99% and 1.72%, respectively, and 7.29% decrease in specific fuel consumption than engine with standard-setting using the same fuel blend. In addition, there was a decrease of carbon monoxide in exhaust emission, and unburnt hydrocarbon was slightly increased.

Effect of various ethanol/diesel cosolvents addition on combustion and emission characteristics of a CRDI heavy diesel engine

Solubility between ethanol and diesel impedes the application of ethanol in diesel engines. The objective of the experiment is to compare combustion and emission characteristics of ethanol/diesel fuels using biodiesel, n-pentanol, tetrahydrofuran (THF) as cosolvents respectively on a diesel engine under variable engine loads, exhaust gas recirculation (EGR) rates, and injection timings. The results show: All tested blends increase the indicated thermal efficiency (ITE) except at low load, and THF/ethanol/diesel fuel exhibits a higher ITE. The Coefficient of Variations of Indicated Mean Effective Pressure (COVIMEP) of ethanol/diesel blends is higher than that of diesel at low load. Under EGR conditions, ethanol/diesel blends run at lower COVIMEP, especially for biodiesel/ethanol/diesel fuel. At higher loads, all ethanol/diesel blends can decrease carbon monoxide (CO) emissions, especially for THF/ethanol/diesel fuel. Excessive retard of injection timing will increase CO and total hydrocarbon (THC) emissions of ethanol/diesel fuels. The soot emissions of THF/ethanol/diesel fuel are lower than those of n-pentanol/ethanol/diesel fuel under higher EGR rates. The effect of injection timing on soot emissions becomes more pronounced at slightly higher EGR rates. Compared to diesel, biodiesel/ethanol/diesel fuel increases nitrogen oxide (NOx) emissions, especially at medium-low load, whereas n-pentanol/ethanol/diesel and THF/ethanol/diesel fuels reduce NOx at low and high loads, slightly increase NOx emissions at medium loads. In conclusion, THF may be a more promising ethanol/diesel cosolvent compared with high alcohols and biodiesel in terms of fuel economy and emissions, especially under EGR and heavy load conditions.

Sustainable Low-Carbon Development of Urban Public Transport: International and Russia’s Experience

The rapid growth of cities all over the world has inevitably led to the aggravation of economic, social and environmental problems. In this regard, developing «green», low-carbon, circular and other new economic models is necessary. Transport sector is an important source of greenhouse gas emissions and air pollutants. The purpose of this work is to assess the impact of urban public transport, especially electric buses, on the air quality. The authors have analyzed international and Russia’s experience of the low-carbon development of urban public transport and evaluated the environmental effects of transitioning to electric buses in Moscow using a regression model and data visualization tools. The results have shown that integrating electric buses into an urban transport system can be considered as a step towards the low-carbon development of the transport sector. The authors have identified a decrease in carbon monoxide (CO) pollution in the districts of Moscow where there are electric bus routes. Although the authors managed to demonstrate positive aspects of using e-buses instead of traditional ones, the proposed hypotheses were not fully confirmed due to limited data and a small number of electric bus routes at an early stage of the project. The results of the work can be used both in theoretical studies of sustainable development and practical implementation of programs for the low-carbon development of an urban transport network

Impact of partial alteration of diesel fuel on the performance and regulated emission of a diesel engine

Biodiesel has become one of the promising solutions for the future energy crisis. This study aims to assess the effect of alteration of fuel (replacing diesel with biodiesel) on the performance and regulated emission in a diesel engine. Biodiesel blends (WCB20) was prepared by mixing 20% of waste cooking oil biodiesel with 80% diesel fuel using a homogeneous mixture. The performance and regulated emission of WCB20 have been evaluated in a multi-cylinder diesel engine at various speeds with a full load condition and compared with diesel fuel. The results indicated that WCB20 offers 6.52% less brake power and 9.01% lower brake thermal efficiency whereas, 36.15% and 32.16% higher BSFC and BSEC in comparison to diesel fuel, respectively. However, regulated emission results showed that WCB20 significantly decrease carbon monoxide, particulate matter, and hydrocarbon by 38.93%, 15.46%, and 21.20% respectively but slightly increase the NOx emission (13.79%). Finally, it can be concluded that partial alteration of conventional diesel fuel using 20% waste cooking oil biodiesel can indicatively reduce the harmful emission.

Rehabilitación respiratoria oportuna y precoz en pacientes con neumonía COVID 19 en un hospital referencial

SARS-CoV-2 is a beta-coronavirus of the same subgenus as SARS and MERS viruses, they share the same gene binding receptor, angiotensin converting enzyme (ACE2). (1) The spectrum of disease severity is varied, with the mild form being the most frequent (81%), and severe disease present in 14% of cases, with critical presentation being present in 5%, with a mortality of 2.3%.(2) The post-pneumonia respiratory sequela caused by beta-Coronaviruses is diffuse alveolar damage with fibrotic lesions; the pathophysiological mechanism is multifactorial, which involves activation of transforming growth factor beta (TGF-β)(3), IL1, IL6, MCP1 and TNF-α secondary to epithelial injury and subsequent inflammation. In addition, exposure to high O2 concentrations and effects of barotrauma, caused by advanced oxygen/ventilatory support, activate the pro-fibrotic TGF-β pathway, resulting in aberrant repair characterized by exaggerated deposition of fibroblasts, myofibroblasts and collagen. Forty-seven percent and 25% of patients who survive moderate to severe COVID-19 pneumonia have decreased carbon monoxide diffusion and predicted total lung capacity, respectively. (4)

The assessment of the engine performance and emissions of a diesel engine fueled by biodiesel produced using different types of catalyst

In the present study, the biodiesel was produced from waste cooking oil using two types of catalyst (homogeneous (Hom. Cat.) and heterogeneous (Het. Cat.)). The produced biodiesels were characterized to obtain their physicochemical properties and fatty acid methyl esters (FAMEs) profile. Then, they were blended with net diesel fuel at volume ratios of 10:90 (B10), 25:75 (B25), and 40:60 (B40) for using in the injection system of a 6-cylinder diesel engine operated at a constant speed of 1500 rpm to compare changes in the combustion (engine performance) and exhaust emissions of engine. The results showed that the catalyst type had an insignificant effect on the physical properties of produced biodiesel such as density, viscosity, flash, cloud and pour point, higher heating value, etc., whereas the compositions of FAME contents slightly changed. On the other hand, the total production duration was lower for the biodiesel produced by heterogeneous catalyst (21 h against 26 h), while the higher amount of energy consumed (2165 against 1650 Wh/L). Blending net diesel fuel with biodiesels slightly improved the engine performance and combustion behavior. The exhaust gas emissions were also showed an appropriate decrease in carbon monoxide (5–40%), unreacted hydrocarbon (40–75%), and smoke opacity (8–25%) emissions using biodiesel produced heterogeneous catalyst. The statistical analysis of results showed that blending the net diesel fuel with 34 vol% of biodiesel and operating the diesel engine at 40% of fuel load can lead to an appropriate engine performance along with a considerably reduction in the exhaust gas emissions.

The effects of n-butanol/gasoline blends and 2.5% n-butanol/gasoline blend with 9% water injection into the intake air on the SIE engine performance and exhaust emissions

The aim of this paper was to investigate the effects of n-butanol/gasoline blends (nBGBs), 2.5% n-butanol/gasoline blend with 9% water injection into the intake air on the engine performance, fuel cost and exhaust emissions in an automobile spark-ignition engine. Experiments have been performed for three different nBGBs, nB2.5 (nB2.5 contains 2.5% n-butanol and 97.5% gasoline in volume basis), nB5 and nB7.5 for five different loads at 3000 and 5000 rpms. The test results showed that nBGBs generally decrease brake specific fuel consumption (bsfc) at all of the selected operating conditions. The maximum reductions of bsfc at 3000 and 5000 rpms have been attained at the levels of 7.22% and 9.99% for nB2.5, respectively. nBGBs decrease carbon monoxide (CO) and total hydrocarbon (THC) emissions at the selected operating conditions. However, nBGBs increase nitrogen oxides (NOx) at 3000 rpm. At 5000 rpm, nB2.5 and nB5 reduce NOx but nB7.5 increases NOx. The NOx could not be reduced as much as desired by applying nBGBs. For this reason, 9% water introduction into the intake air with nB2.5 (nB2.5-WI9) have been applied to decrease NOx. The test results showed that nB2.5-WI9 and nB2.5 decrease NOx approximately 58% and 9%, respectively at 5000 rpm. nB2.5-WI9 reduces CO more than nB2.5 at two engine speeds. However, nB2.5-WI9 increases THC and bsfc more than nB2.5. Total fuel cost for nB2.5 and nB2.5-WI9 become higher than neat gasoline. However, nB2.5-WI9 shows higher fuel cost as compared to nB2.5.

Experimental investigation of spark plug gap on performance and emission of single cylinder 4S SI engine with Hydroxygen as an additive

The Hydroxygen as an additive to the gasoline is used in the present experimental investigation for reducing the fuel consumption and conserve the fast depleting fossil fuel without any engine modification. The Hydroxygen was produced from the developed electrolytic cell and the power of the alternator through the battery was used. The power to the electrolytic cell was controlled by circuit. During the experiment, the voltage and current across the electrolytic cell was measured by introducing the other circuit and data was collected. The experiment was conducted on Discover bike engine with constant Hydroxygen gas flow of 600 ml per hour to the engine intake manifold. Performance and exhaust gas emission parameters were measured by keeping 0.6 mm and 0.8 mm electrodes gap of spark plug (EGSP). Overall performance and emission was found to be optimum for 0.6 mm EGSP with Hydroxygen addition with the maximum relative decrease in brake specific fuel consumption 50.43%, increase in brake power and brake thermal efficiency (ƞ%) are 77.20% and 101.76% respectively, the maximum relative decrease in carbon monoxide, un burned hydrocarbon and nitrogen oxide are 96.96%, 90.29%, and 81.73% respectively.

Numerical investigation of the effect of two-step injection (direct and port injection) of hydrogen blending and natural gas on engine performance and exhaust gas emissions

The present work investigates the effect of two-step fuel injection on a four-cylinder engine which has been altered from port injection to direct injection. Hydrogen enriched compressed natural gas (HCNG) blend has been utilized as a substitute in replacement of gasoline. Initially, CNG as a 10% of the total fuel mass fraction is injected into the air manifold and the remaining 90% fuel is HCNG which is injected into the cylinder by direct injection. Primarily, the CNG was injected at 160° BTDC with 20° stroke duration. HCNG fuel was injected at 130° BTDC with a 50° stroke duration being injected from (0%–40%) step.AVL software has been utilized for this investigation to inspect the engine performance, efficiency, fuel consumption, and exhaust emissions. The collected data indicates that by injecting 30% HCNG blend, the brake power, brake thermal efficiency, and in-cylinder pressure is increased from 8% to 13.64%, and the specific fuel consumption is reduced from 6.2% to 18% due to a rise in flame propagation speed in the combustion chamber. The addition of hydrogen has decreased carbon monoxide and unburned hydrocarbons by up to 14% on a complete combustion. NOx has been increased due to the increase in the exhaust gas temperature.

Alterations in Respiratory Function Test Three Months after Hospitalisation for COVID-19 Pneumonia: Value of Determining Nitric Oxide Diffusion.

Three to four months after hospitalisation for COVID-19 pneumonia, the most frequently described alteration in respiratory function tests (RFTs) is decreased carbon monoxide transfer capacity (DLCO). Methods: This is a prospective cohort study that included patients hospitalised because of SARS-CoV-2 pneumonia, three months after their discharge. A clinical evaluation, analytical parameters, chest X-ray, six-minute walk test, spirometry and DLCO–DLNO analysis were performed. Demographic variables, comorbidities, and variables related to the severity of the admission were recorded. Results: Two hundred patients completed the study; 59.5% men, age 62 years, 15.5% admitted to the intensive care unit. The most frequent functional alteration, in 27% of patients, was in the DLCO–DLNO combination. This alteration was associated with age, male sex, degree of dyspnoea, poorer perception of health, and limited ability for physical effort. These patients also presented higher levels of D-Dimer and more residual radiological alterations. In 42% of the patients with diffusion alterations, only reduced DLNO was presented, along with lower D-Dimer levels and less capillary volume involvement. The severity of the process was associated with the reduction in DLCO–DLNO. Conclusions: The most sensitive RFT for the detection of the sequelae of COVID-19 pneumonia was the combined measurement of DLCO–DLNO and this factor was related to patient health status and their capacity for physical exertion. In 40% of these cases, there was only a reduction in DLNO, a finding that may indicate less pulmonary vascular involvement.

Effect of multi-walled carbon nanotubes on pre-vaporized palm oil biodiesel/air premixed flames

In regard to the current state of global energy, the high demand for traditional fossil fuels and their negative environmental impact have led to an increase of interest in the development of renewable clean fuels. Recently, nano-additives such as carbon nanotubes (CNTs) have been considered as a potential additive to increase fuel combustion performance. Thus, we experimentally studied the combustion characteristics of multi-walled carbon nanotubes (MWCNTs) blended palm-oil biodiesel/air mixtures at a wide range of equivalence ratios, 0.7–1.6. Experiments were conducted at atmospheric pressure and a temperature of 550 K to ensure full vaporization of the liquid biodiesel fuel. Concentrations of the MWCNTs in the mixture were varied from 25 to 200 ppm for two different groups of nanotubes having outer diameter ranges of 10–20 nm and 30–50 nm. The results showed that both laminar burning velocity and blowoff velocity were increased with the additions of MWCNTs. Besides, the flammability limits of MWCNTs blended biodiesel/air premixed flames were also extended at both fuel-lean and fuel-rich conditions. It was also observed that the MWCNTs of 10–20 nm experienced more noticeable improvements in the combustion characteristics compared to the MWCNTs of 30–50 nm. After reaching the highest enhancement, a further increase in the concentration of MWCNTs generally caused less improvement in the laminar burning velocities of the premixed flames. Besides, the addition of MWCNTs increased nitrogen oxides and decreased carbon monoxide concentrations in the combustion products.

Performance of Coconut Biodiesel Fueled Diesel Engine with Exhaust Gas Emission Analysis

Biodiesel fuel is biodegradable, Sulphur free, non-toxic and environmentally friendly. Current research focuses on coconut biodiesel production using crude coconut oil. Both one and two step transesterification methods were utilized to analyze the effect of free fatty acid on the transesterification process while the two-step transesterification reported highest yield biodiesel percentage of 84% compared to the one step i.e. 72%. The fuel properties found compatible with standards. The biodiesel blends fueled diesel engine performance tests were performed on diesel engine Water-cooled, four stroke, single cylinder, Direct Injection System (Kubota - RK95-1-NB-RDK). The biofuel blend with 10% of coconut biodiesel and 90% Petro-diesel shown the highest brake horsepower of 8.809KW, engine power of 1.685KW and mechanical efficiency of 15.24%. While in exhaust gas emission analysis, the hydrocarbon and carbon monoxide decrease with the increasing biodiesel blend whereas the nitrogen oxides increased.