Norrizam Jaat

The effect of nozzle diameter, injection pressure and ambient temperature on spray characteristics in diesel engine

Mixture formation of the ignition process is a key element in the diesel combustion as it influences the combustion process and exhaust emission. Aim of this study is to elucidate the effects of nozzle diameter, injection pressure and ambient temperature to the formation of spray. This study investigated diesel formation spray using Computational Fluid Dynamics. Multiphase volume of fluid (VOF) behaviour in the chamber are determined by means of transient simulation, Eulerian of two phases is used for implementation of mixing fuel and air. The detail behaviour of spray droplet diameter, spray penetration and spray breakup length was visualised using the ANSYS 16.1. This simulation was done in different nozzle diameter 0.12 mm and 0.2 mm performed at the ambient temperature 500 K and 700 K with different injection pressure 40 MPa, 70 MPa and 140 MPa. Results show that high pressure influence droplet diameter become smaller and the penetration length longer with the high injection pressure apply. Smaller nozzle diameter gives a shorter length of the breakup. It is necessary for nozzle diameter and ambient temperature condition to improve the formation of spray. High injection pressure is most effective in improvement of formation spray under higher ambient temperature and smaller nozzle diameter.

Effect of High Injection Pressure of Algae and Jatropha Derived Biodiesel on Ignition Delay and Combustion Process

This paper presents the investigation of the effect of high injection pressure on the ignition delay period and emission characteristics. Few experiments were conducted in a rapid compression machine (RCM). Four types of fuels were tested inside a RCM which are standard diesel (SD), Algae biodiesel (A2), Palm Oil biodiesel (B5, B10, and B15) and Jatropha biodiesel (J5, J10, J15). The experiments were conducted at high injection pressure of 130 MPa. The ambient temperature of constant volume chamber at the time of fuel injection was set at 850 K. The results indicate that the combined factors of specific of ambient temperature and higher injection pressure produces shorter ignition delay time. B5 has the shortest ignition delay with 1.5 ms. Biodiesel has the shorter ignition delay which is prolonged with increasing biodiesel content in the blends. In terms of emissions, Carbon dioxide (CO2), Carbon monoxide (CO), hydrocarbon (HC) and smoke emissions decreased with all biodiesel-diesel blends. However, oxides of nitrogen (NOx) emission of the biodiesel was relatively higher than those of the diesel under all test conditions. In addition, the increase of blends in terms of biodiesel ratio was found to be significant in enhancing the combustion process.

Effect of Algae-Derived Biodiesel on Ignition Delay, Combustion Process and Emission

Algae oil methyl esters produced from algae oil were blended with diesel at various volumetric percentages to evaluate the variations in the fuel properties. Microalgae biodiesel production has received much interest in an effort for sustainable development as the microalgae seem to be an attractive way to produce the biodiesel due to their ability to accumulate lipids and their very high actual photosynthetic yields. Correlations between fuel properties, including the calorific heat, density, kinematic viscosity, and oxidation stability of the Algae oil-diesel blends, and the blending ratio of the algae biodiesel have been established. As a result, low blending ratio of the Algae oil with diesel was recommended up to 2vol % in comparison with other type of biodiesel-diesel blends. The objective of this research is to investigate effect of biodiesel blending ratio on ignition delay, combustion process and emission for different type of biodiesel. The combustion tests of the Algae-Derived biodiesel blends were performed in a Rapid Compression Machine (RCM). The combustion tests were carried out at injection pressure of 130 MPa and ambient temperature were varied between 750 K and 1100 K. The result from the experiment is compared with Palm-Oil biodiesel which are varied in biodiesel percentage from 5vol% to 15vol% and jatropha biodiesel. Higher ignition delay period were clearly observed with higher blending ratio. It seems that increasing blending ratio exhibits relatively weakens in fuel ignitibility and therefore prolongs the ignition delay of algae biodiesel. A2 had the lowest ignition delay period when compared with J2, B5, B10 and B15 due to lower density that present in A2 molecules.The concentration of carbon dioxide and nitrogen monoxide in the exhaust gas increased with higher blending ratio while the concentration of carbon monoxide and hydrocarbon decreased.

Comparision on dynamic behavior of diesel spray and rapeseed oil spray in diesel engine

Fuel-air mixing is important process in diesel combustion. It significantly affects the combustion and emission of diesel engine. Biomass fuel has high viscosity and high distillation temperature and may negatively affect the fuel-air mixing process. Thus, study on the spray development and atomization of this type of fuel is important. This study investigates the atomization characteristics and droplet dynamic behaviors of diesel engine spray fuelled by rapeseed oil (RO) and comparison to diesel fuel (GO). Optical observation of RO spray was carried out using shadowgraph photography technique. Single nano-spark photography technique was used to study the characteristics of the spray while dual nano-spark shadowgraph technique was used to study the spray droplet behavior. Using in-house image processing algorithm, the images were processed and the boundary condition of each spray was also studied. The results show that RO has very poor atomization due to the high viscosity nature of the fuel when compared to GO. This is in agreement with the results from spray droplet dynamic behavior studies that shows due to the high viscosity, the RO spray droplets are large in size and travel downward, with very little influence of entrainment effect due to its large kinematic energy.

Analysis of the Effect of Injection Pressure on Ignition Delay and Combustion Process of Biodiesel from Palm Oil, Algae and Waste Cooking Oil

Biodiesel is a domestically produced, renewable fuel that can be manufactured from vegetable oils, animal fats, or recycled restaurant grease for use in diesel engines. The objective of this research is investigation the effects of the variant injection pressure on ignition delay and emission for different biodiesel using rapid compression machine. Rapid Compression Machine (RCM) is used to simulate a single compression stroke of an internal combustion engine as a real engine. Four types of biodiesel which are waste cooking oil, crude palm oil, algae and jatropha were tested at injection pressure of 80 MPa, 90 MPa and 130 MPa under constant ambient temperature at 950 K. Increased in injection pressure resulted shorter ignition delay proven by WCO5 which decreased from 1.3 ms at 80 MPa to 0.7 ms at 130 MPa. Meanwhile, emission for CO2 increased due to better fuel atomization for fuel-air mixture formation lead to completed combustion.

Experiment on the Effects of Storage Duration of Biodiesel produced from Crude Palm Oil, Waste Cooking oil and Jatropha

Biodiesel based on vegetable oil is an alternative that had various advantage in term of sustainability and environmental attractive compare to others conventional diesel. Biodiesel is product of any fat or oil that derived from any organic sources through a refinery process called transesterification process. This research investigates the effects of storage duration and variant ambient condition on the biodiesel properties and characteristics. In this study, there are three types of blending which is 5vol% blends ( 5vol% plant oil 95vol% diesel), 10vol% blending (10vol% plant oil and 90vol% diesel) and 15vol% blending (15vol% plant oil and 85vol% diesel) each called CPO5 (crude palm oil 5vol%), CPO10 (crude palm oil 10vol%),CPO15 (crude palm oil 15vol%), JO5 (jatropha oil 5vol%), JO10 (jatropha oil 10vol%),and JO15 (jatropha oil 15vol%) respectively. Biodiesel samples were stored at indoor condition and outdoor condition for a 3 months period. The fuel properties such as acid value, viscosity, density, water content and flash point are observed with the laboratory instrument. Flash point value and water content increased under both of indoor and outdoor condition and a steady data for viscosity and density. However, acid value at indoor condition nearly constant but increased dramatically for outdoor condition over the time.

Influences of Fuel Additive, Crude Palm and Waste Cooking Oil on Emission Characteristics of Small Diesel Engine

Major research has been conducted on the use of input products, such as rapeseed, canola, soybean, sunflower oil, waste cooking oil (WCO), crude palm oil (CPO) and crude jatropha oil as alternative fuels. Biodiesel is renewable, biodegradable and oxygenated, where it can be easily adopted by current existing conventional diesel engine without any major modification of the engine. To meet the future performance and emission regulations, is urged to improve the performance and exhaust emissions from biodiesel fuels. Hence, further investigation have been carried out on the emission characteristics of small diesel engine that fuelled by variant blending ratio of WCO and CPO with booster additive. For each of the biodiesel blends ratio from 5 to 15 percent volume which are WCO5, WCO10 and WCO15 for WCO biodiesel and CPO5, CPO10 and CPO15 for CPO biodiesel. The exhaust emissions were measured at engine speeds varied at 2000 rpm and 2500 rpm with different booster additive volume DRA (biodiesel without additive), DRB (0.2 ml) and DRC (0.4 ml). Emissions characteristics that had been measured were Hydrocarbon (HC), Carbon Monoxide (CO), Carbon Dioxide (CO2), Nitrogen Oxide (NOx), and smoke opacity. The results showed that increased of blending ratio with booster additive volume significantly decreased the CO emission, while increased in NOx and CO2 due to changes of fuel characteristics in biodiesel fuel blends.

Flame spread behavior over combustible thick solid of paper, bagasse and mixed paper/bagasse

Flame spread behavior on combustible solid is one of important research related to Fire Safety Engineering. Now, there are a lot of combustible solid composed from mixed materials. In this study, experiments have been conducted to investigate flame spread behavior over combustible solid composed by paper, bagasse and mixed paper/bagasse. Experimental data is captured by using video recording and examined flame spread shape and rate. From the results obtained, shows that the different materials produce different flame spread shape and rate. Different flame shape is seen between all types of samples. Flame spread rate of 100% paper is faster than the one of 100% bagasse. Based on the result, it is also inferred that the material composition can be influenced on the flame spread shape and flame spread rate of mixed paper/bagasse.

Analysis of high injection pressure and ambient temperature on biodiesel spray characteristics using computational fluid dynamics

Efficiency of combustion engines are highly affected by the formation of air-fuel mixture prior to ignition and combustion process. This research investigate the mixture formation and spray characteristics of biodiesel blends under variant in high ambient and injection conditions using Computational Fluid Dynamics (CFD). The spray characteristics such as spray penetration length, spray angle and fluid flow were observe under various operating conditions. Results show that increase in injection pressure increases the spray penetration length for both biodiesel and diesel. Results also indicate that higher spray angle of biodiesel can be seen as the injection pressure increases. This study concludes that spray characteristics of biodiesel blend is greatly affected by the injection and ambient conditions.

Computational Fluid Dynamics Analysis of High Injection Pressure Blended Biodiesel

Biodiesel have great potential for substitution with petrol fuel for the purpose of achieving clean energy production and emission reduction. Among the methods that can control the combustion properties, controlling of the fuel injection conditions is one of the successful methods. The purpose of this study is to investigate the effect of high injection pressure of biodiesel blends on spray characteristics using Computational Fluid Dynamics (CFD). Injection pressure was observed at 220 MPa, 250 MPa and 280 MPa. The ambient temperature was kept held at 1050 K and ambient pressure 8 MPa in order to simulate the effect of boost pressure or turbo charger during combustion process. Computational Fluid Dynamics were used to investigate the spray characteristics of biodiesel blends such as spray penetration length, spray angle and mixture formation of fuel-air mixing. The results shows that increases of injection pressure, wider spray angle is produced by biodiesel blends and diesel fuel. The injection pressure strongly affects the mixture formation, characteristics of fuel spray, longer spray penetration length thus promotes the fuel and air mixing.