Mirjana Puharic

Growth in the aviation sector has brought great benefits, but also an increased impact on the environment. Air transport has a significant impact on climate change, even to the extent that global climate change dictates the limitations of its development and the areas in which aviation needs to adapt its land and flight operations. The main polluta...

Procena i predviđanje fizičko-hemijskih parametara površinskih voda veoma je značajno u procesu kontrole kvaliteta i upravljanja vodama. Svrha ovog rada je identifikacija izvora zagađenja i predviđanje promena u kvalitetu vode Kolubarskog sliva. Varijacije kvaliteta vode ispitivanog rečnog sliva identifikovane su korišćenjem multivarijantnih statis...

Procena i predviđanje fizičko-hemijskih parametara površinskih voda veoma je značajno u procesu kontrole kvaliteta i upravljanja vodama. Svrha ovog rada je identifikacija izvora zagađenja i predviđanje promena u kvalitetu vode Kolubarskog sliva. Varijacije kvaliteta vode ispitivanog rečnog sliva identifikovane su korišćenjem multivarijantnih statis...

21. vek sa sobom nosi mnogobrojne tehnološke benefite, koji su manje ili više ecofriendly naročito u pogledu najvrednijeg resursa - vode. Međutim, kako svakodnevno raste ekološka svest ljudi, tako se i proizvodne tehnološke linije i procesi okreću prema prirodi i prečišćavanju već zagađenih medijuma životne sredine. To je slučaj i sa gradskim otpad...

In a present that is limited by carbon concentrations and the near future that will face the serious consequences of climate change due to the overuse of fossil fuels. We cannot say for sure about the quantities of fossil fuels in the earth's crust, and the world still relies on them. On the other hand, the need for an increasing amount of electric...

Od pojave prvih sintetičkih materijala do današnjeg vremena, plastika je postala veoma zastupljena i rasprostranjena u našim životima. Plastika se može uočiti na skoro sve strane u našoj okolini, u domaćinstvima, parkovima i igralištima za decu, izletištima. Od sintetičkih materijala je napravljena naša odeća, mobilni telefoni, ambalaža vode i hran...

Kada govorimo o zagađenju životne sredine znamo da zagađenje predstavlja prisustvo nepoželjnje materije/supstance, u nepoženjim koncentracijama, na nepoželjnoj lokaciji tj. medijumu životne sredine. Kada govorimo o vodi kao medijumu životne sreidne koji se zgađuje, ona je pored vazduha “najranjivi” prirodni resurs životne sredine, ali i najzagađeni...

In the times of significant development of high-speed train transportation and taking the primacy over the others, one of the major designing tasks is to predict accurately and fast the vehicle’s main performances, especially aerodynamics. Motivated by the bionic design of representative Japan’s train Shinkansen, the presented bionic design was bas...

In modern business, uncertainty and risks are increasing, and the available time is not enough to make the right decisions. The consequence of such a dynamic environment is the creation of flexible organizations and efficient managers who are ready to quickly respond to market demands using modern technologies. In this paper the model for prelimina...

In this paper the model for preliminary estimation of number of employees in airline by using of artificial intelligence tools. It is assumed that the tools of artificial intelligence can be applied even for complex tasks such as defining the number of employees in the airline. The results obtained can be used for planning the number of employees,...

This paper presents the results of multiphase flow numerical simulations in ventilation mill-mixing duct with louvers separator of Kostolac B power plant (Serbia). Simulations are performed using both the mixture model of the Euler-Euler approach and Euler-Lagrange approach of ANSYS FLUENT software package. The gas mixture distribution at the burne...

This work presents the research results of the aerodynamic brake influence, mounted on the high-speed train's roof, on the flow field and overall braking force. The train consists of two locomotives at each end and four passenger cars between, with 121m of overall length. Aerodynamic brakes are designed to generate braking force by means of increas...

This paper presents the results of 3D numerical flow simulation in the ventilation mill (VM) and air mixture channel (AMC) of Kostolac B power plant, where a centrifugal separator with adjustable blade angle is used. Numerical simulations of multiphase flow were performed using the Euler-Euler and the Euler-Lagrange approach of the ANSYS FLUENT sof...

This paper presents results of the impact plate surface modification of the ventilation mill in the Kostolac B power plant (Serbia). The modification is based on 3D numerical simulation of multiphase flow around a grinding wheel. High velocity of sand particles in the ventilation mill causes strong wear of the impact plates. The multiphase flow sim...

This paper presents the results of research on the influence of an air wave, caused by a passing train on a person standing on the station platform. The tests were conducted in a real environment, at a railroad, on a doll and in a subsonic wind tunnel, on a 1 : 20 scale model of a high speed passenger train. Also, simulations of airflow, induced un...

The results obtained in the parallel testing of the epoxy-glass compo-site specimen, using conventional mechanical methods and thermography, are presen-ted. The tensile properties of composite were followed by thermography. The tempera-ture changes on the tested sample were continuously recorded enabling the prediction of the critical stresses, whi...

This paper presents the results of numerical simulations of multiphase flow in ventilation mill-ducts system of the power plant Kostolac B. This flow of diluted gas and solid piece of coal and sand mixture, was modeled using software ANSYS FLUENT 12, with a mixture model in the Euler-Euler approach. Process simulation involves geometry modeling, me...

This paper presents the results of numerical flow simulation in ventilation mill of Kostolac B power plant, where louvers and centrifugal separator with adjustable blade angle are used. Numerical simulations of multiphase flow were performed using the Euler-Euler and Euler-Lagrange approach of ANSYS FLUENT software package. The results of numerical...

This paper presents the results of simulations, carried out with the Fluent software, for a high speed train moving at 70 m/s for 4 cases: the train configuration without aerodynamic brakes, the train configuration with one aerodynamic brake, with two, and with three aerodynamic brakes deployed over the roof of the train. We have determined the bra...

Nondestructive methods are dominant in diagnosing the status and protection of all kinds of contemporary industrial object, as well as object of industrial heritage. Laser methods open wide possibilities of research in the field of diagnosis and metal processing. This paper presents the results of laser radiation interaction (wavelength λ = 694.3 n...

Copper and aluminum are materials that have technological, functional and expressive value in the contemporary art and architecture. Therefore, studying the pos-sibilities of protection of these materials by using non-destructive method is of great impor-tance when it comes to cultural heritage. The paper presents the results of interactions of la-...

Preventive care, research, and restoration of cultural heritage objects requires multidisciplinary research and the involvement of experts of different profiles, using high technology equipment. Nondestructive methods dominate in the diagnosis of the situation and protection of cultural heritage objects. The application of lasers has opened many po...

This paper presents the aerodynamical brake system, as second brake system, in cases when it is necessary to speed down the train or at emergency situations when primary brake system Is out of order. In this brake system, braking force is a result of aerodynamical drag generated on pulled-up aerodinamical brake panels. These panels are especially e...

Some results of experiments performed in water cavitation tunnel are presented. Pressure coefficient (Cp) was experimentally determined by Laser Doppler Anemometry (LDA) measurements. Two models were tested: model of airplane G4 (Super Galeb) and hydrofoil of high speed axial pump. These models are not prepared for conventional pressure measurement...

The flow in a two-dimensional symmetric convergent-divergent supersonic nozzle with and without a deflector at the exit plane was tested experimentally and numerically. Combined optoelectronic devices were used to demonstrate the possibilities of the shadow and schlieren methods and holographic interferometry for the flow visualization especially i...

This paper describes measurement of the aerodynamic pressures produced by passing trains. The focus for this study is to determine the localized effects such as potential damage to train's caot. The paper presents the experimental researches of train models, carried out in subsonic wind tunnel. The testing has been conducted in two stages. First st...

A review of experimental studies in aerodynamics of trains of great speeds when passing each other on open tracks. This paper describes measurement of the aerodynamic pressures produced by passing trains. The focus for this study is to determine the localized effects such as potential damage to windows. The paper presents the experimental researche...

Classical methods and the laser-Doppler-anemometry (LDA) application for the test section calibration of a water-cavitation tunnel is presented. The results show that the LDA is the best method for calibration and the classical methods satisfy the needs of standard tests. The advantages of the LDA are illustrated by determination of the pressure co...

This paper presents the numerical simulation results of the multiphase flow in the ventilation mills of Kostolac B power plant, where blinds and centrifugal separators with adjustable blade angles are used. The numerical simulation was performed using the mixture model in the Euler-Euler approach of commercial ANSYS FLUENT software package. The gas...

The paper shows the results obtained in the simultaneous testing of DX55D steel specimens using conventional methods and thermography. The main aim of the testing was to relate the temperature changes of the specimens, continuously recorded by thermography, with the stress – extension diagram. It enables to predict reaching the critical stresses wh...

U radu su prikazani rezultati delovanja laserske svetlosti, talasne dužine λ = 694,3 nm (rubinski laser, Q-switch mod uzorka do 20×10 3 J/m 2 . Dijagnostika stanja složenih, savremenih indus-trijskih postrojenja, kao i predmeta industrijske i kul-turne baštine u kojima su ugrađeni bakar i aluminijum, interdisciplinarna je aktivnost koja se temelji...

Aerodynamic problems in railway trains are closely associated with flows occurring around trains. The main objective of this paper is to present the results of the finite element method for stress and stability analysis of aerodynamic brakes in high speed trains (HST). The aerodynamic brake is defined as a stiffened plate subjected to lateral press...