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In the present scenario, biodiesel is a very highly renewable fuel and an excellent alternative to diesel. It is nontoxic, having high flash point and tremendous performance. But, the main drawbacks are poor atomization and incomplete combustion which could be overcome by incorporating additives and catalysts. The blends that we have used in our study are B20, B40, B60, B80 and B100 of which the optimum performance from tests was the B20 biodiesel. To further improve its performance, Graphene quantum dots (GQD) nanoparticles (100ppm) were added and the performance tests were carried out under varying loads from 0.5 kW to 3.5 kW. It was found that the HC, CO and NOX emissions reduced by 13.87%, 32.31% and 13% respectively and the efficiency increased by almost 3.5%, with the addition of GQD. [ABSTRACT FROM AUTHOR]

Electrospray, or Electrohydrodynamic Atomization (EHDA), is a technique in which a high voltage is applied to a liquid to create aerosols. When a fluid is subjected to an adequately strong electric field induced by high voltage, its surface deforms into a cone from whose apex a jet is formed and disintegrates into microscale or nanoscale charged droplets. This multi-physics phenomenon can be applied in various areas, such as medicine delivery, 3-D printing, space thruster design, etc., owing to its low cost, high production rate and ease of control compared with other techniques. In electrospray, spraying regime can be controlled by varying parameters such as applied voltage, liquid flow rate, spraying distance, etc., and the most desirable spraying mode is the single cone-jet due to its stability, controllability, and relatively high yield rate. In this work, the authors introduce a simulation code to investigate the characteristics of electrospray operating in the cone-jet mode utilizing OpenFOAM. In our simulations, Gauss's Law and Charge Conservation Equation are solved simultaneously with Navier-Stokes equations and VOF interface tracking method to numerically produce transient multiphase electrohydrodynamic mechanism. Computational results are validated by experimental data with close agreement. [ABSTRACT FROM AUTHOR]

The aim of the paper is to compare two optical measurement methods for the measurement of the atomization properties of the two-phase nozzle. The measured liquid is the water at a room temperature and the atomization fluid is the compressed air. The first method is the Phase Doppler Anemometer (PDA) and the second is the Laser Diffraction LD. The two commercial instruments were tested, together with inhouse photogrammetric measurement of the nozzle outlet. The tested droplets have Sauter Mean Diameter approximately around 10 µm. The presented results could be useful for the estimation of the advantages and disadvantages of the methods and recommend the application in the wide field of aerosol technology. The first results of the comparison show the fine resolution with PDA system, but the tuning of the setup requires several times more time. The accuracy of the LD is sufficient. The important advantage of the PDA system is knowledge of the velocity distribution for each measured droplet. [ABSTRACT FROM AUTHOR]

The atomizer is a crucial component in spray columns used in mass transfer applications. Proper function of the atomizer can enhance mass transfer and reduce sorbent evaporation and droplet drift (physical loss). Commonly used atomizers for spray column application suffer from excessive droplet drift and high spray polydispersity. Flat fan sprays were beneficially used to reduce droplet drift in agricultural applications and in studies dealing with CO2 capture. Six 3D printed flat fan atomizers with different internal channel geometry (elliptical, cone-shaped) were tested at four inlet pressures in this study. The liquid sheet breakup length and spray cone angle derived from high-speed visualization are compared for each atomizer design. No systematic difference was found between the elliptical and cone-shaped channels. The spray cone angle and breakup length were corelated only with experimental regimes (Reynolds number and Weber number). Perforations were responsible for the breakup of the liquid sheet at lower injection pressures, whereas the combined effect of perforations and waves dominated the liquid sheet breakup at higher injection pressures. [ABSTRACT FROM AUTHOR]

The steam turbines are still the essential machines for the energy transformation. For all the deployment of the non-fossil energy sources the steam turbine remains the most important energy transforming device. In the current situation when the daily operation of the turbines is not predictable due to electricity supply from the photovoltaic and the wind power plants, the turbines work in the non-design conditions, the danger of the blade's erosion caused by the coarse droplets is assumed. The purpose of this paper is to suggest the possible formation process of the coarse droplets in the steam turbine. The current studies were focused mostly on the measurement or identification of the coarse droplets in the steam turbine but the explanation of the archived results was not sufficient. The influence of the flow field behind the blade on the liquid film atomization was studied. The first measurements of the detailed characteristic of the flow field in the wind tunnel for the qualitative analysis of the phenomena were performed with promising results. [ABSTRACT FROM AUTHOR]

When liquid droplets move in another liquid or in a gas phase, under certain conditions the droplets are collapsed up to form a number of smaller droplets [1-3]. This process is found in atomization, liquid extraction, absorption, separation and a number of other processes. The collapsing process is most pronounced when the droplets are moving in a uniformly rotating environment, because as the droplets move, for example, from the center to the periphery of the rotor, those parameters which contribute to the collapsing of the droplets are intensified. [ABSTRACT FROM AUTHOR]

The present work describes ultrasonic atomization as a novel approach for the synthesis of oil-in-water emulsion. The mechanism of droplet formation is explained using capillary wave hypothesis and cavitation hypothesis. The effects of oil concentration, surfactant concentration, atomization frequency and flowrate to atomizer on particle size are investigated using particle size and optical microscopy analysis. With increase in oil concentration from 1 to 20%, the thickness of liquid film increases which leads to increase in particle size. The increase in surfactant concentration from 0.5 - 1% contributed to decrease the particle size, however further increase in surfactant concentration resulted in agglomeration of particles. The increase in atomization frequency from 20 - 130 kHz is beneficial in decreasing particle size from 65 - 17 µm. The increase in flowrate to atomizer increases the particle size. Microscopic observations for all parameters are in agreement with the results obtained from particle size analysis. [ABSTRACT FROM AUTHOR]

This article presents the feasibilities of bacterial disintegration using ultrasonic atomization. Ultrasound creates acoustic cavitation, which by its effects represents a high gradient of pressure in the form of a shock wave and a local force effect. In our case, the ultrasonic excitation produces a fine micron mist of 3 micrometers. The generated microcavities create a cavitation cloud that is able to disintegrate the foam-forming bacteria or even inactivate bacterial cells. The main goal of the research is the use of ultrasound to disintegrate the foam-forming bacteria during the impact of acoustic cavitation on living cells. [ABSTRACT FROM AUTHOR]

Liquid dispersion on a wire mesh is a phenomenon that is utilized in many industrial applications, such as rotating packed beds. It is a very simple method of liquid atomization without a need for complex nozzles. This research focuses on an elementary case of a liquid dispersion on a crossing of two wires. Experiments were carried out in a wind tunnel to elucidate the influence of counterflow air velocity on a liquid sheet and droplets. High-speed camera was used to capture the impact of droplets on the crossing. Images were then processed using MATLAB® addon PIVlab. The effect of the input parameters, including a liquid flow rate in the range of 3.8 to 12 kg/h and air flow velocity varying from 0 to 9 m/s on the angle and velocity of dispersed droplets downstream of the crossing, was investigated. Finally, a qualitative description of the dispersion was evaluated. Results show that with an increasing liquid flow rate, the droplets dispersed in a wider angle. On the other hand, the influence of the air counterflow is significant only for low liquid flow rates. The atomization rate, determined by the number of small droplets, was better for higher liquid flow rates. [ABSTRACT FROM AUTHOR]

Currently, meat products processed with smoke are in great demand. It has been established that when the neck is smoked by atomization of the smoking flavor, the amount of phenols and carbonyl compounds, the resistance of the meat product to hydrolytic and oxidative spoilage is higher than in case of traditional smoking. Studying the chemical composition found that there is no significant difference in the content of protein, fat, sodium chloride, the yield of smoked-cooked meat products is higher by 1.7%, the water-binding capacity is higher by 4.2% compared to the traditional smoked product. It has been proven that atomization smoking enhances the color of the finished product, specific taste and aroma, which practically do not differ from traditional smoking products. Aerosol spraying of a smoking preparation increases the diffusion of smoking substances into the product, which ensures its safety during storage. [ABSTRACT FROM AUTHOR]

The development of additive technologies in the Russian Federation is constrained by the lack of indigenous base for the production of metal powders. SPbPU has developed, manufactured and introduced a plasma atomizer. It provides atomization of metal powders and alloys of various chemical compositions. The data on the main technological parameters of atomization of nickel alloy Inconel 718 and titanium alloy Ti-6A1-4V are presented in the paper. It is shown that by optimizing the spraying mode the possibility to obtain alloy powders with a high level of sphericity and a minimum number of particles with surface and internal defects. The chemical compositions of the obtained particles are almost identical to the composition of the initial atomized materials. Samples for the mechanical testing were made from the obtained powders by the SLM method. The results of mechanical properties tests show that the properties of samples made by 3D printing methods from powders sprayed by plasma atomization methods are identical to the properties of materials made and heat-treated by traditional methods. [ABSTRACT FROM AUTHOR]

Drop impact on a heated substrate is one of the most important objects occurring in the main two types of cooling applications such as quenching of metals and the cooling of lasers and electronic devices. The paper reports a study of the interaction of the water drop of 10 µl impacting on a heated sapphire plate with a temperature varied within a range of 23-80°C. Dynamic viscosity at this temperature range is decreased from 1004 to 355.1×10−6 Pa·s. The influence of the temperature on liquid viscosity may lead to a substantial difference in drop dynamics. The main changing parameters are the liquid column at splashing and secondary droplets atomization. A considerable decrease of the liquid column contact diameter and an increase of the liquid column height at the splashing stage are shown with the decreasing viscosity. Secondary droplets atomization from the liquid column with increasing temperature is revealed. [ABSTRACT FROM AUTHOR]

The paper presents the results of theoretical, numerical and experimental investigations of combustion and detonation initiation in heterogeneous poly-dispersed mixtures. The problems of fuel droplets atomization, evaporation and combustion and the non-equilibrium effects in droplets atomization and phase transitions were taken into account. The effects of droplets size non-uniformity and spatial distribution non-uniformity on mixture ignition and flame acceleration were investigated for strong and mild initiation of detonation: by a shock wave and spark ignition followed by deflagration to detonation transition (DDT). Peculiarities of jet injection and ignition in reaction chamber are studied. [ABSTRACT FROM AUTHOR]

An experimental study of the jet evolution of boiling water and ethanol with an increase of superheat level in the flow for a number of flow swirl speeds has been made. The degree of influence of the rotational speed at various degrees of superheat (low, high and attainable one) on atomization has been revealed. A decisive role has been established in the spraying of high-intensity swirls under conditions of low superheats. At high and attainable superheats, the effect of intense boiling on atomization becomes decisive. A complete jet breakup, which is observed in the absence and at low rotational speeds, does not occur under conditions of high-intensity swirl. 1/f fluctuations have been detected in the precessing jet at low superheats of the liquids. [ABSTRACT FROM AUTHOR]

A two-step mist atomization and solution immersion method was applied in order to grow Ag+ doped ZnO nanorod/ZnO seed layer with improved c-axis preferential growth orientation. The thin films were annealed at RT - 600 °C in order to study the properties of the thin films with varying annealing temperature. The acquired thin films were characterized by FESEM and XRD to study the morphological and structural properties. From FESEM micrographs, it is found that the thin film annealed at 500 °C owned enhanced growth along c-axis (002) crystallographic plane, as supported by XRD result. These results demonstrate that the annealing temperature may tune the morphological and structural properties of the Ag+ doped ZnO thin films. [ABSTRACT FROM AUTHOR]

Results of experimental studies of coaxial atomization process of slurry fuel with plasticizer in aerodynamic simulator of an energy boiler furnace are presented. Values f the characteristic sizes of spray cone zones have been established: core, middle and outer zones. Ranges of velocities and sizes of droplets in the flow at pressure of 0.4 MPa (slurry fuel) and 0.38 MPa (air) have been determined. Quantitative values of slurry fuel droplets with different velocities in the process of its coaxial spraying have been obtained. [ABSTRACT FROM AUTHOR]

The article discusses the numerical simulation of kerosene atomization in injector of a gas turbine engine using the volume of fluid method. The method of modeling the primary and secondary film (jet) break-up under the influence of high-speed airflow is developed. Verification with experiment information about which is available in open sources is carried out. The Rosin-Rammler distribution for atomization of kerosene in injector of a gas turbine engine is received. [ABSTRACT FROM AUTHOR]

In this paper, a computational method to predict the dimensional changes in some powder metallurgy materials is used. The samples prepared from pre-alloyed iron base powders produced by atomization (< 45, 45-63, 63-100, 100-150, >150μm) were the materials analyzed in this paper. The analyzed powders were compressed in a mold using uniaxial pressing at 400 and 600 MPa with the disc dimensions of ∅ 8 × 6 mm. The sintering temperature was approximately 1.150°C for 60 and 90 minutes. The density in green and sintered state of iron-based alloys, the mechanical properties and dimensional changes were evaluated. A computational model using input and output parameters was used. Particle size, pressure and sintering time were defined as the input variables of the model. Porosity and hardness was used as the output variables of the model. It is observed that the values obtained by computational method are in good correlation with the experimental values. The viability of the computational model used is confirmed. The computational method studied in this paper can be used as an alternative to predict the dimensional changes of some iron-based materials obtained by powder metallurgy route. [ABSTRACT FROM AUTHOR]

With the advancement of technology organizations are becoming increasingly dependent on successful deployment of information systems. To deal with the IS complexity, developers require competence. However, the question "What is competence?" is still a topic of further deliberation in general, and in IS field in particular. Contemporary research critiques the concept of competence as confined to a narrow and instrumental view, for instance just as application of skills and knowledge. The narrow and instrumental view of competence does not give full attention to the information systems developers nor to the situations where the competence is enacted. To enhance the understanding of competence, we critically analyze the prevailing concepts of competence in general and in particular within the IS field. Based on the results of our analysis we propose an expansion of the concept competence to include 'competence-as-skilful-coping' based on a holistic perspective where developers 'being-in-the-world' act appropriately in unique and complex contexts. Such contexts may involve the developers of the systems, the users of IS-es to be developed, related information systems, manual routines, and the technology used. We present and analyze a case searching for the suggested concept of 'competence-as-skilful-coping'. [ABSTRACT FROM AUTHOR]

The quality of fuel atomization in diesel engine, commonly represented by the mean drop size, is critical for fuel-air mixture, and for the rate of fuel evaporation and combustion. Poor quality fuel-air mixtures are a source of harmful exhaust gas components, such as nitrogen oxides and particulates. In spite of advanced technologies, mentioned components still are not eliminated from combustion products. The article presents the results of the impact of fuel pump delivery rate and fuel viscosity on the course of atomization. The determination of droplet size was based on the Sauter Mean Diameter (SMD). In addition, changes in the value of SMD during injection have been analyzed. The delivery rate of an injection pump was changed in the 25% - 100% range of the maximum rate. Liquids used for the tests had a viscosity varying in the range 4 -36 mm2/s, which contains the viscosities of fuels recommended by marine engine makers. The experiment was performed at a test stand featuring a plunger injection pump, spraying fuel in the air of atmospheric pressure. The quality of spray was examined by means of a Spraytec STP 5929 analyzer. An image of a fuel spray was recorded by a High-Speed HHC Camera X1. Raising the pump delivery rate above the nominal dose and increasing liquid viscosity led to more sprays generated by the atomizer nozzle. Increased fuel pressure, in turn, (controlled injector opening pressure) brought about a smaller number of sprays. The standard methodology used for the determination of droplet size in a spray (in the whole cycle of injection) did not reveal significant changes of mean droplet size. Alternate increases and reductions of engine load or revolutions (changes of fuel dose), are conditions typical of ship manoeuvring, especially in a harbour. Such conditions may cause the division of one fuel dose into a number of sprays, which changes the process of forming fuel-air mixture and may affect the composition of exhaust gas. The observed phenomena refer to the process of precise fuel atomization control. [ABSTRACT FROM AUTHOR]

India being an underdeveloped country was facing low capital formation, traditional approaches to production and providing services which used to be costly. However, after adopting the globalization, it has opened its doors to foreign direct investment and for the new technology as a result of lots of MNCs have come to India and have established their manufacturing and services centres bases. This has its impact on the fierce competition in the market. The only solution in such a situation is to start using latest technology, resort to automation and see that the productivity improves at the same time costs are cost drastically. For this purpose lot of investment is required. To the extent possible the Govt. of India is providing funds and the banks are also having a favourable approach. The impact of automation and technology advancement on employment generation is certainly felt. In certain cases it is a temporary phenomenon but particularly the IT and IT enabled services will be severely hit in times to come. The introduction of latest technology is also paving the way for new types of jobs. Conversion of jobs into starting self-employment enterprises is in the process. All the stake holders i.e. govt., industry, as well as the individuals should prepare to face this situation with well preparedness. [ABSTRACT FROM AUTHOR]

Spray nozzles are used for the industries as the cleaning, cutting, and spraying. The nozzle will came so many varieties and usually can be classified according to specific mode of atomization. The present study experimentally is to investigate the spray development for the droplet size of the water in the nozzle AL-75 by using the high-speed camera. The spray development is divided into five stage and each stage consist of time from 0 milliseconds (ms) to 32 milliseconds (ms). For this experiments, the supplied pressure has been use is 1 bar, 2 bar and 3 bar for the liquid and 1 bar, 3 bar and 6 bar for the air pressure. The experiment data were obtained from the released of the mist spray nozzle in water liquid 100%, water 90% mix with lime 10% (L10W90) and water 70% mix with lime 30% (L30W70). The results shows that for the lower pressure, the time taken for the spray to become fully development is longer compared to the higher pressure. [ABSTRACT FROM AUTHOR]

In this paper, growth mechanisms of ZnO nanostructures on non-seeded glass, 6 nm and 12 nm Au seed layer obtained by mist-atomization was proposed. ZnO films were successfully deposited on glass substrate with different thickness of Au seed layer i.e. 6 nm and 12 nm. The surface and optical properties of the prepared samples were investigated using Field emission scanning electron microscopy (FESEM) and photoluminescence (PL). FESEM micrograph show that ZnO nanostructure deposited on 6 nm Au seed layer has uniform formation and well distributed. From PL spectroscopy, the UV emission shows that ZnO deposited on 6 nm Au seed layer has the more intense UV intensity which proved that high crystal quality of nanostructured ZnO deposited on 6 nm Au seed layer. [ABSTRACT FROM AUTHOR]

In our work the Se content was evaluated in the soils of Nitra region and in the grains of wheat grown on these soils as well. Samples were collected during harvesting from 28 localities. The Se content was determined by AAS method using the electrothermic atomization vapor both in the grains and in the soils. The average Se content in the grains of wheat of Nitra region was 53 µg.kg-1. This value exceeds the average content in Slovakia (28.9 µg.kg-1). The Se distribution in the whole area of Nitra region was different. In Nitra district in the soils with alkaline soil reaction (Chernozem, Fluvigleyic Pheozem) the Se content was high. The very low Se content in grains was determined in the districts of Topoľčany and Zlaté Moravce, although its soil content was high (brown soil with medium acid or neutral soil reaction). The average value of total soil Se content of Nitra region exceeded the limit value 1.25 - times. The Se grain content grown on the soil of the north of Nitra region was non-detected despite the fact that its soil content was over-limited. The Se intake by the plants depends on its form in the soil and on the soil type as well. [ABSTRACT FROM AUTHOR]

The evaporation features for the atomized flow of suspension on the base of water with ground admixtures in an area of high-temperature combustion products of liquid flammable substance (acetone) were investigated experimentally by the optical methods of gas flow diagnostic and the high-speed video recording. The scales of influence of clay and silt concentration in droplets of atomized flow on the intensity of its evaporation were determined. The approximation dependences describing a decrease in typical size of suspension droplets at various values of ground admixtures were obtained. [ABSTRACT FROM AUTHOR]

In the reported research work, the microscopic droplet velocity at different axial and radial locations downstream to the nozzle exit was studied by using a non-intrusive Laser Doppler Anemometry (LDA) techniques. These velocity measurements made in the viscous fluid spray sterams were used to predict the different breakup regimes in the flow. It was noticed that the droplet velocity decreased sharply downstream to the nozzle exit, whereas steady decrease in velocity was seen along the radial directions. For shorter injection time periods, the velocity downstream to the nozzle was not following the general breakup model. However, along the radial direction it exactly followed the discussed model. Along the spray centerline, the velocity was decreasing sharply even at far points from the nozzle exit. It was difficult to identify the core region, transition region and fully developed spray region in the flow. It revealed that the jet breakup was not completed yet and further disintegration was taking place along the spray centerline for shorter injection periods below 250 ms. [ABSTRACT FROM AUTHOR]

Twin-fluid atomizers underwent a significant development during the last few decades. They are common in many industrial applications such as fuel spraying, melt atomization and food processing. This paper is focused on the evaluation of four different twin-fluid atomizers. The aim is to compare the quality of sprays generated by various atomizers with similar dimensions and in the same operating regimes. A phase-Doppler anemometry (PDA) and particle image velocimetry (PIV) were used to measure spray characteristics such as velocity and size of the droplets. Measured data were used to compare droplet size distribution and to evaluate steadiness of the spray. Visualisations were made to support measured data and to clarify the principles of primary atomization and its influence on the spray. [ABSTRACT FROM AUTHOR]