bluuebunny/crossref_metadata_2025 huggingface dataset:
Time-based management concept on the basis of the organizational-managerial innovations in a logistic company
Authors: Shamina Lubov , Borisova Iolanta
Published: November 2018

Time could be considered as an important competitive advantage of logistics companies. In fact, execution time is the most significant factor affecting the performance of the supply chain. Regarding the issue mentioned above, it seems relevant to develop the economic and organizational-managerial paradigm from value-based thinking to a time- based. The focusing on the reducing the time cycle suspends the competitive advantage, received by the logistics company due to the shortening response time for customer requests. Therefore, we have set the time factor in the basis of the logistics company performance appraisal and the main effort should be focused on reducing the delivery time cycle from the moment of the order receipt to its final delivery to the consumer.
The role of the railway network of border areas in interstate cooperation
Authors: Popova Natalia , Korkhovaya Elena
Published: November 2018

The border areas of countries are aimed at playing a special role in the development of general economic and social relations, enhancing the geopolitical significance of regional interstate relations. The purpose of the work is to study and show the modern economic complex of border regions on the example of Russia and Mongolia, in which railway transport plays a significant role. Statistical and analytical comparison as a method of scientific analysis allowed examining in detail the territorial production complex of a large region, its resource dependence, and the conditionality of the functioning by the configuration of transport routes and transport accessibility indicators, both in Russia and Mongolia. The Russian railways, which connect Siberia and the Far East with the European regions of the country, continue to provide interdistrict and interregional economic relations at the present time. The Mongolian railways, which have a smaller length, perform a linking role between the fields of raw materials and the points of its processing or further transportation. The study showed that railways continue to be the basis for interregional cross-border connections. However, as the shortest transport route between the countries of Western, Central, Eastern Europe, and the countries of Central, East, and South-East Asia, the railways of the region in question, uniting the border regions of Mongolia and Russia, can strengthen their role in interstate cooperation and become the most important part of the international Eurasian transport corridors - the Steppe Route and the Silk Road.
Optimization of work performance of snow removal work trains on the basis of linear programming
Authors: Manakov Aleksey , Abramov Andrey , Ilinykh Andrey , Aksenov Vladimir
Published: November 2018

The introduction of monitoring systems for the work performance of special rolling stock and monitoring the load of snow removal work trains revealed a number of shortcomings in the planning, organization, and recording of work performed by snow removal work trains. The elimination of the identified problems is possible on the basis of optimization of work performance, the implementation of which can be achieved on the basis of existing systems with appropriate additional functionality. For this purpose, in the framework of the theoretical studies presented in the paper, a methodology for optimization of work performance of snow removal work trains has been developed. Linear programming is adopted as a method of solving the optimization problem. On the basis of the algorithm for solving the transport problem, the problem of minimizing the cost of snow removal from various sections of the track by the existing park of work trains is formulated, for which a mathematical model is constructed that includes the objective function and the corresponding restrictions. The results of the study show that the widespread use of work planning on the basis of the presented optimization methodology will make it possible to make the most efficient use of snow removal equipment and, as a result, to reduce the cost of this type of railway track maintenance work.
Prospects of scientific research in the field of active and passive safety of vehicles
Authors: Evtukov Stanislav , Golov Egor , Sazonova Tatiana
Published: November 2018

Road traffic injuries cause colossal socio-economic damage to the society as a whole and irreplaceable losses for injured persons and their relatives. Huge amount of road and transport accidents are caused by human error. The paper studies statistics of road accident rate and influence of human factor on safety. In connection with revealed direct dependence of accident rate and the severity of its consequences on the driver errors, the evolutional path from vehicles without automation of any functions to entirely autonomous vehicles is considered in the paper. In continuation of the dynamic evolution of vehicles, the perspectives for the development of active and passive safety of vehicles are proposed. Reducing the need for full or partial control of a car by the driver provides ample opportunities for people with disabilities to use them, which is an additional incentive to the development of autonomous vehicles. Due to the existing difficulties caused by the unavailability of either road users or legislative or regulatory authorities for switching to autonomous vehicles, there may be scientific and related problems in their implementation in the Russian transport system.
Management of structural and mechanical properties of moulding compound using mineral additives
Authors: Shakhov Sergey , Nikolaev Nikita
Published: November 2018

The purpose of work: the choice of the rational composition of the batch mixture, which improves the molding properties of the silt loams in the production of wall ceramics by the method of plastic molding. In the course of the study, the fraction-size distribution and morphological features of the fractions were analyzed on a photometric sedimentometer FSX-6K and by optical microscopy. Determination of the plastic strength of elasto-visco-plastic systems was carried out by Rehbinder’s conical plastometer. The values of fast and slow elastic and plastic deformations were determined on an installation operating on the principle of a parallel- shifting plate. For molding compounds with various corrective mineral additives, optimum values of molding moisture in which the compound is not adversely affected by shortage and excess moisture have been experimentally established; moduli of fast and slow elastic deformation and other structural and mechanical characteristics are determined. The percent values of the reduced deformations were obtained on the basis of rheological curves of disperse systems in the axes “deformation - shear time”. It is established that the additions of components of different genesis and with different fraction morphology affect the deformation behavior of the molding compounds.
Standardization and unification of algorithms of organizational and technical solutions in the process of performance of licensable activities
Authors: Burovtsev Vladimir , Davydov Anatoliy , Dementev Alexey
Published: November 2018

An indispensable prerequisite for achieving the strategic objectives of the development of Russian railway complex is to strictly ensure the security of the licensable activities. At the same time, one of the main reserves for improving the economic efficiency of the transport industry will be the organization of a full competitive environment in the transport services market, creating opportunities for the implementation of the entrepreneurial initiative, and reducing the level of administrative barriers in this sphere. In this regard, the goal of scientific research is of a great urgency. This goal is to develop a set of coordinated measures of state regulation that can create conditions for the full development of the transport services market in conditions of regulating business activity in the process of carrying out licensable types of activities. The achievement of this goal is possible by the methods of institutional analysis of the administrative regulations for the provision of a state service for licensing of the activities, as well as by forming complex programs for the interaction of regulators on the basis of emerging synergistic effects. The presented paper reflects the main results of analysis and synthesis of organizational and technical solutions for the performance of licensable activities in railway transport. The results of the research are intended to contribute the improvement of the efficiency of modern state governance mechanisms in solving key problems in the development of the railway transport industry.
Strategic analysis as a tool for development of a transport company (on the example of the company from the Tyumen city)
Authors: Makovetskaya E.G. , Yuzikhanova E.G.
Published: November 2018

The article presents an assessment of the activities of the construction company from the Tyumen city. An important stage in developing an effective strategy of the company is strategic analysis, which should give a real assessment of own resources and capabilities in relation to the state (and needs) of the external environment in which the firm operates. On the basis of this analysis, rational choice of strategies from a possible set of options should occur. The conducted SWOT- analysis has allowed to formulate the potential directions, capable to make financial indicators of the construction company much better.
Public transport as a social-legal phenomenon in the example of the city of Nizhnevartovsk (Khanty Mansi autonomous area Ugra)
Authors: Lez’er V.A. , Semeryanova N.A. , Kopytova A.V.
Published: November 2018

The urgency of the problem under investigation is caused by the presence of contradictions that have arisen in the public and private regulation of relations in the provision of services to the population in the sphere of urban public transport and predetermines the need for coordinated legal regulation of transport relations, taking into account the specific functioning of public urban transport and its regional features. Such an approach will allow building public relations in the field of transportation in order to ensure not only effective regulation, but also its effective protection. Conclusions: In this connection, it is proposed to create a regional concept of transport development that takes into account the socio-economic characteristics of the region on the basis of monitoring of administrative-territorial units in order to identify priority areas and increase transport accessibility in every city in the region. Further improvement of the legislative regulation of this sphere will be futile without realizing that under current conditions the socio-economic and natural conditions of each particular region should be taken into account; it is simply necessary, as well as building parity between the population, the transport companies and the state.
Water-saving processes control of an airport
Authors: Bieliatynskyi Andrii , Osipa Liudmyla , Kornienko Bogdan
Published: November 2018

This article presents a systematic approach to solving a problem with rational use of an airport’s water resources. Life cycle programming of the technological systems of wastewater purification allowed to consider comprehensively the problem of economical water consumption. The life cycle programming was adopted as the methodological basis for constructing a logical scheme of tasks of an airport’s water-saving processes. On the basis of the proposed logical tasks diagram it became possible to develop an algorithm and software for automatized control over airport’s water-saving processes. The purpose of the work is to implement a systematic approach for control over water-saving production aviation processes of the airport and representation of the developed algorithm for control. It may be concluded that the implementation of the given algorithm on the basis of computer technology will increase the efficiency of wastewater purification and significantly reduce the fresh water consumption.
Load combinations in performance-based designing of earthquake-resisting structures
Authors: Kuznetsova Inna , Uzdin Alexander , Sabirova Oypasha
Published: November 2018

Load combinations for seismic and other loads are considered. To this aim the equiprobable sets of loads with the corresponding probabilities are analyzed. The combination of motor-car and seismic loads is considered in details. The log-normal distribution law was used as a distribution density functions for car load. The distribution of the earthquake event stream was taken according to Poisson's law, which makes it possible to estimate the design seismic intensity. In the frame of this intensity peak ground accelerations were estimated. The dependence of the combination coefficient of the seismic load on the combination coefficient of the motor-road load was obtained. The results obtained show, that combination coefficients in Performance Based Designing should be calculated separately for each input level. For the design earthquake and the maximum design earthquake the combination coefficients vary significantly. The values of the combination coefficients are determined mainly by the frequency of the design actions and to a lesser extent they depend on the seismic activity of the building site.
Cracks in upper road layer at negative temperature change: modelling and forecasting
Authors: Gavrilov Timmo , Kolesnikov Gennady
Published: November 2018

Low-temperature cracking is one of the main reasons for the deterioration of the upper layer of roads in regions with cold climate. The material of the top layer can be, e.g., asphalt concrete or frozen soil. In this paper it is assumed that the temperature of the underlying layer is non- negative, i.e. a model in the form of a two-layer structure is used. A large number of works aimed at preventing wear are known, but the interdisciplinary problem of low-temperature cracking in seasonal freezing of soils remains relevant. In publications, as a rule, consider the destruction of freezing, that is, with a decrease in temperature. Much less attention is paid to the modeling and forecasting of damage to the upper layer of roads, if its temperature rises, but remains negative. In this case, the layer is compressed and the appearance of wave-like irregularities on the day surface (buckling) is possible. The objective of the current study was modeling the conditions of occurrence and prediction of damage to the upper layer of roads when the changes negative temperature. The paper uses methods of mathematical modeling of mechanical systems, as well as adaptation of the known results of other authors. The estimation of the critical wavelength at a bend of the compressed upper layer is given. The results of numerical simulation are consistent with the experimental data known in the literature.
Analysis of the stress-strain state of the process pipeline to tank junction in case of subsidence
Authors: Tarasenko Aleksandr , Chepur Petr , Gruchenkova Alesya
Published: November 2018

The article presents the developed finite element model of the emergency oil discharge system pipelines with a junction to the tank. Numerical modeling was carried out in the ANSYS software complex, with the help of which the model of the junction under consideration was created, considering the geometric and physical nonlinearity of the structure. A design model for the structure deformation is proposed in case the base subsidence develops. With the help of the tabulated function, it was possible to determine the value of subsidence at which critical stresses arise in the metal. Dependences of the maximum effective stresses in the metal structures of the wall to emergency discharge system pipeline junction on the RVS-20000 subsidence values are obtained. When the tank subsidence value is 144 mm, the limiting state in the wall and the junction to the pipeline occurs and the metal passes into the state of developing plastic deformations.
Superplastic forming of shells from sheet blanks with thermally unstable coatings
Authors: Anishchenko Aleksandr , Kukhar Volodymyr , Artiukh Viktor , Olga Arkhipova
Published: November 2018

The article is devoted to superplastic forming of non-uniformly heated sheet blanks from aluminum alloy AMg6M. To create an uneven temperature field over the surface of the blank, coatings made of sublimated substances were used from at temperatures 50…150°C below the superplastic forming temperature (450°C for AMg6M alloy). An aqueous solute of chloride and ammonium iodide having a sublimation temperature at normal pressure and a latent heat of conversion equal to 338 and 404°C, 330 and 355kJ/kg, respectively, was sprayed onto the central zones of the blanks. Superplastic forming of shells was carried out in two modes: 1) with simultaneous sublimation of the coating; 2) with the beginning of the sublimation of the coating upon reaching the height, which is formed by the workpiece, equal to 20-30% of the final shell height. The experiments showed a decrease in the thickness of the shells to be formed up to 4-10% on the working surface of the shells (without taking into account their flange zones) and the savings of sublimate during superplastic forming in the second mode. The optimal subliming coating for AMg6M alloy was ammonium chloride.
The study of the level of financial literacy of students of transport universities
Authors: Nikonova Yana , Lunina Tatiana , Prudnikov Aleksey , Arshba Ludmila
Published: November 2018

The purpose of this study is to characterize the state of financial literacy of students of transport universities on the basis of analysis of the results of empirical data of social research. In the framework of applied research, a significant amount of experience in assessing financial literacy has been gained, but in the academic science, the research of this kind is not enough to form a generally accepted concept and a detailed theory. Because of the resulting contradiction, the authors had to search for new approaches to conducting the study of financial literacy and interpreting the results. The system, in particular - the structural and functional approach and the sociocultural approach were chosen as the main ones. These approaches are widely used for study of similar phenomena and already proved themselves in science. As a result of the comparative analysis of the all-Russian level of knowledge and skills in the field of financial literacy and the level of students in the economic and non-economic fields of study in transport universities, the hypothesis was proved that students of non-economic fields of study have a lower level of financial literacy compared to students in economic fields of study and all-Russian level. Therefore, it is required to develop programs of various content and complexity to increase the level of financial literacy for these groups.
Reproduction of human potential of JSC “Russian Railways” - a source of increasing labor productivity
Authors: Davydov Anatoliy , Dementev Alexey , Burovtsev Vladimir
Published: November 2018

The ongoing reform of Russian railway transport entailed a change in the form of ownership and status previously all known monopoly represented by the Ministry of Railways of Russia, and its transformation into the Open Joint Stock Company “Russian Railways”. The change in the form of ownership of one of the largest subjects of the transport services market in Russia had a certain effect on the competitiveness of the country’s transport system and, in some way, reduced the level of monopolization of railway transportation. The methods for calculating the labor productivity of transport companies in Russia generally require a deeper method of measuring the performance of personnel, based on assessing the level of development of the company’s human potential in modern economic conditions, when the relationship between the results of personnel work and the company’s targets determines its competitiveness. The authors propose a new methodology for managing labor productivity and employee incentives, which is caused by the actualization of a number of functions of personnel management of transport companies and the transformation of production activities depending on changes in the external environment, which previously did not play a fundamental role, but now have a decisive influence on the efficiency of the company’s activity and social production of the country. Assessment of the performance of companies can also cause problems with the management system of labor productivity and human development, if the strategic goals and objectives of the company’s development are not known to a particular employee, are not balanced or outside of its sphere of influence.
“Collaboration” as a mechanism for implementation of the technological revolution in the operating processes of railway transport
Authors: Komarov Konstantin
Published: November 2018

This paper discusses the experience of the collaboration of five Russian railways in Siberia and the Far East, four universities of railway transport, and ten laboratories of the Siberian Branch of the Russian Academy of Sciences. The activity of the collaboration was carried out as a part of the Program of Scientific and Technical Cooperation of Railways, Universities of Ministry of Railways in the regions of Siberia and the Far East, and the Siberian Branch of the Russian Academy of Sciences. The program was approved by the Minister of Railways of the Russian Federation and the Chairman of the Siberian Branch of the Russian Academy of Sciences. Within the framework of the activity of this one of the first collaborations for railways in Russia, sets of technical, technological, project documentation and application software packages were developed; and also specialized sites for diagnostics and repair of the track were equipped. The program showed its effectiveness, and the obtained results were recommended for implementation on all railways of the country.
Approaches to university education integration into innovative ecosystem
Authors: Amelin Stanislav , Enina Elena , Pahomova Yulia
Published: November 2018

Professional realization and education items – are most important in our life. And this is no wonder by considering how much time each of us spends on study and on work and how much depends on it. And of course, radical changes which are taking place at the present time have no choice but affect these spheres. Today in Russia there is a lot of attention paid on discussion of innovations, digital economics, labor efficiency and competitive ability. However these plans are unrealizable without systematic approach to human capital development including attraction and retention of best minds as well as ensuring conditions for growth of progressive companies-recruiters. One of the most important tasks of these companies is on creation of new high-quality working places, inherent for technological, diversified, creative economics – economics of knowledge. By human capital production it becomes principal the focus on “soft” skills: on width of view, ability to hold discussion, to present results in various ways, to communicate, to work in teams. And then the question arises not only what we teach, but also how and where we teach. There are considered in the article items of educational process in university, what must university do, in order to get rid of the imitation in research activity, how to solve the problem of interdisziplinarity in university; how to form the organizational cultures and activity norm in university.
Formation of estimate cost of road-repairing works with the use of composite cationic bituminous structures
Authors: Ovsiannikov Andrei , Vorotyntseva Anna , Bolgov Vladimir
Published: November 2018

The necessity of the formation of the estimated costs for the production of road-repairing works with the use of composite cationic bituminous structures is dictated by the lack of this kind of works in existing estimated costs base, because this type of materials has not been used yet. Estimated costs are intended both for the determination of the road-repairing work costs and to justify the effectiveness of the use of a new type of materials. This article describes the main concepts associated with the formation of estimate costs base for the determination of the road-repairing work costs. It also shows the formation of norms and prices for the installation of coatings with the use of composite compounds based on cationic bituminous structures.
Characteristic of business environment of road construction in Russia
Authors: Mishlanova Marina , Syzrantsev Gregory
Published: November 2018

The article notes the importance of the subsystem of road construction in the national economy. The insufficiency of methodological support for assessing the environment of economic activity is indicated. Statistical data on the state of the Russian road network are presented, disproportions of its development are revealed and problems of road construction are diagnosed. The article provides an assessment and comparative analysis of the life cycle of road construction enterprises. The complex of indicators of assessment of the environment of activity of the enterprises of road construction is offered, results of calculation of density and renewability of the environment for a row of years are considered. The level of state regulation of investment and construction activities in relation to the transport system is discussed. The negative factors and directions of improving the environment of road construction enterprises in Russia are highlighted.
Constituents of sustainable development potential of a logistics company
Authors: Avdeeva Elena , Belyantseva Oksana , Smorodina Elena
Published: November 2018

The article explores the potential for sustainable development of the company in a dynamic environment. The components of the potential are composed of external and internal. For their identification and analysis, tools such as SNW- and SWOT-analysis are used on the example of a construction industry enterprise. It was revealed that internal stability is formed under the influence of management tools. It includes organizational, investment, production, technological and financial sustainability. External stability includes global, regional and national. For a deeper analysis it is desirable to apply the indicator of sustainable development. With its help, it is possible to analyze the development of the enterprise in terms of dynamics, compare different enterprises and identify bottlenecks among the components of sustainable development potential. The indicator is flexible and takes into account industry specifics. The authors concluded that the innovative component should be present in all areas of the enterprise.
Scenario approach in forecasting the efficiency of infrastructure projects for transport supply of international trade
Authors: Nekhoroshkov Vladimir , Nekhoroshkov Evgeniy
Published: November 2018

In the current conditions for the development of the world economic system and against the backdrop of growing contradictions of various participants in trade and economic relations formed under the influence of both purely economic and political factors, when making investment decisions for the development of international business and projects, including infrastructure ones, it is necessary to take into account associated risks. Using the methodological approaches of system analysis of large-scale investment projects, which use expert methods to reduce the level of influence of risk factors and uncertainty, an analysis of the sensitivity of individual infrastructure projects to the influence of environmental factors was carried out. As a result of the study, it was shown that scenarios for the development of the external environment differently affect the infrastructure projects of different purposes that are allocated in the work. Each type of infrastructure projects has its own peculiarities: projects of transit value serve the trade and economic relations of European and Asian countries, infrastructure projects of regional importance contribute to strengthening trade and economic relations of border areas, and certain commercial railway lines provide access to mineral deposits. The findings can be used in forecasting the development of continental trade and economic relations, both in general and in individual industries, as well as in substantiating large-scale infrastructure projects that solve the problem of transport supply of international trade.
Methodology for the development of innovation projects on the basis of competitiveness indexes
Authors: Maslyukova Ekaterina , Anoshina Yuliya , Khakimov Almaz , Aleksandrovskiy Maxim
Published: November 2018

This paper presents the results of research in the field of developing innovation projects on the basis of the identification of factors of competitiveness. The principles of formation of competitiveness, including the principle of systematicity, goal-setting, efficiency, adaptability, uncertainty, and innovativeness, are substantiated. A model for the development of a competitive innovation project based on an analysis of external and internal factors providing competitive advantages is proposed. As a result of the research, an integral index of competitiveness of innovation projects was formed, characterizing the level of innovation achieved and allowing substantiating the directions for further development of investment and construction projects.
Models of attraction of private investments into the port infrastructure
Authors: Vasilyeva Elena , Polyakova Irina
Published: November 2018

The authors set the purpose to study the models of attraction of private investments into the port infrastructure in Russia for the sake of the development of transport infrastructure of the country in general. The prospects of the port infrastructure development, the used mechanisms of public-and-private partnership in this sphere with its specifics and legal support as well as some practical examples of implementation of public-and-private partnership projects in the ports in Russia and in the world are considered.
Methodological approaches to risk assessment of real investment projects
Authors: Bogomolova Ekaterina
Published: November 2018

Risk management is impossible without systematically assessing the level of significance of the risks identified in the project. Within the scope of the paper, the distinctive features of various qualitative and quantitative methods for assessing the risks of real investment projects are emphasized. The paper analyzes some of the existing methods of risk assessment in terms of their advantages and disadvantages of application in order to facilitate the selection of the most convenient method for a particular project.
Numerical investigation of boiling and forced convection heat transfer in inclined porous enclosure using modified enthalpy formulation
Authors: Alomar Omar Rafae , Mohammed Rafie Rushdy , Mohammed Karam Hashim
Published: November 2018

Two-Phase flow in an inclined rectangular porous media, under unsteady-state condition, has been numerically investigated in this article, based on the modifiedh-formulation of Two-Phase Mixture Model (TPMM). The governing equations have been discretised using Finite Volume Method (FVM) and solved iteratively in a SIMPLE-like manner. Effects of various parameters on the flow and temperature fields have been investigated, which clearly demonstrated that the inclination angle strongly affect the boiling initiation. Recirculating flow has been observed when the inclination angle θ>0˚. The results clearly indicated that the operating conditions and the porous medium properties have significant effects on the initiation and termination of phase change process. A closer inspection of the results reveals that the presence of a critical inclination angle depending on the value of K*and, Re1which correspond to a maximum values of vapour volume. The modified h-formulation requires significantly less computational time as compared with the existingH-formulation of TPMM.
The application of Fourier transform to the identification of temperature distribution in HFE-7100 flow boiling in an annular minigap
Authors: Hożejowska Sylwia , Piasecka Magdalena
Published: November 2018

In the paper the results of investigations into HFE-7100 flow boiling heat transfer in a cylindrical minigap a 1 mm wide created between the external glass pipe and the copper pipe were discussed. A cartridge heater located axially heated fluid flowing along the minigap. The cooling fluid temperature and pressure at the inlet and the outlet to/from the minigap and temperature of the heater in 18 points were measured. Two-dimensional mathematical model for heat transfer coefficient determination was proposed. It was assumed that in the test section the heat transfer process was in steady state and the fluid flow was laminar. The temperature of the metal pipe near the heater was assumed to satisfy Laplace’s equation. The problem formulated in this way was solved by two methods: the Fourier transform and the Trefftz method. The working fluid temperature was calculated depending on the flow type: for single phase flow with boiling incipience and for two-phase flow, respectively. The heat transfer coefficient at the fluid – copper pipe interface was calculated due to the Robin condition. Local heat transfer coefficient values obtained from the Fourier transform and from the Trefftz method were similar. Results were presented and discussed.
Numerical analysis of lifted hydrogen flame
Authors: Iqbal Sohail , Pfeiffelmann Björn , Benim Ali Cemal , Joos Franz
Published: November 2018

A numerical analysis of a turbulent lifted H2/N2 flame is presented. As combustion mechanisms, a large spectrum is considered including single-step and two-step, as well as detailed mechanisms. As combustion models, various models are considered that treat turbulence-chemistry interaction in different ways, including the Eddy Dissipation Concept and the Laminar Flamelet Method. For turbulence modelling Reynolds Averaged Numerical Simulation and Large Eddy Simulation approaches are used. Results are compared with measurements.
Development and validation of an inverse method for identification of thermal characteristics of a short laser pulse
Authors: Łapka Piotr , Pietrak Karol , Kujawińska Małgorzata , Malesa Marcin , Oniszk Łukasz
Published: November 2018

The paper presents development and validation of an inverse method for the identification of thermal characteristics of a short single laser pulse which stroke in a metal sample. The inverse method was applied to find unknown power of the laser pulse, the dimensionless shape parameter of the super-Gaussian function which describes the beam spatial profile as well as beginning and end times of the exposition of the metal sample to the laser pulse. The proposed inverse algorithm was based on the Levenberg-Marquardt technique as well as on temporal and spatial distributions of temperature on the rear surface of the sample, i.e., the opposite to the irradiated one, measured using the experimental stand. The performed investigations showed that the problem was ill-posed but good accuracy was obtained. The low sensitivity of registered temperature to changes in both power and duration of the pulse affected the retrieving accuracy most significantly. Moreover, the dependence of solution of the inverse problem on the initial guess was observed. The accuracy was also affected by low temporal resolution (500 Hz, with the exposure time from 0.2 to 1 ms) of the IR camera. This resolution affected the temporal sampling of measured temperatures. Despite these problems, the method was able to retrieve unknown pulse parameters with 20-25% accuracy.
Numerical study of the quenching of a laminar premixed hydrogen flame
Authors: Pfeiffelmann Björn , Benim Ali Cemal
Published: November 2018

A numerical analysis of the quenching of a laminar, premixed hydrogen-air flame is presented. A global and a detailed reaction mechanism are considered. First, one-dimensional flame propagation is analyzed and the models are validated based on the predicted flame speed. Subsequently, the quenching near a solid wall of a duct is analyzed, within a two-dimensional, steady-state formulation. Finally, propagation of a flame front through a quenching mesh, within an unsteady, two-dimensional analysis is considered. It is observed that the global mechanism does not predict a quenching of the flame by the mesh, whereas the detailed mechanism does.
Modelling of propane emissions from a tank containing a liquefied phase
Authors: Salamonowicz Zdzisław , Makowski Radosław
Published: November 2018

During gas-phase release from the tank containing liquefied gas, the phenomenon of boiling, heat transfer from moist air to the tank, heat exchange between shell, liquid, and vapor, and mass loss can be observed. The aim of this paper is modelling the thermal response of the tank containing liquefied gas during jet emission of the vapor phase. The model takes into account heat exchange between air, tank’s shell, liquid phase, vapor phase and mass balance. The proposed model predicts: pressure inside the tank, tank’s shell temperature in part with liquid and vapor, the temperature of the liquid phase and vapor phase, and mass loss from the tank. The results of the theoretical model were compared with experimental results. An experiment based on the typical home container for LPG, containing 10 kg of propane (27 dm3 volume) was conducted. In general, the proposed model predicts well the changes in measured parameters temperatures and pressure - during vapor phase emission from a tank containing liquefied gas.
Thermal performance and redesign of beam stoppers under superficial heat transfer from intense ion beams in matter
Authors: Pilan Zanoni André , Briz Monago Jose Antonio , Calviani Marco
Published: November 2018

In the Linear accelerator 3 (Linac 3) and Low Energy Ion Ring (LEIR) at CERN dedicated beam stoppers intercept ion beams for machine and personnel protection whenever required. The interaction of accelerated ions and the stopper induces through-thickness heat deposition in the stopper material as deep as a few hundreds of micrometers. Following a multi-layered geometrical discretization this paper discusses the thermal and structural performance of the stoppers under different ion beams (Pb, Xe, Ar). Design considerations based on the projected range of different ions in target materials (aluminum, steel and copper alloys) are discussed. An improved design for ion stoppers based on thermo-structural performance and projected range is proposed.
Numerical study of the effect of forced convective flow on dropwise condensation by thermal LBM simulation
Authors: Zheng Shaofei , Eimann Ferdinand , Fieback Tobias , Gross Ulrich
Published: November 2018

The enhancement mechanism of forced convective flow on dropwise condensation over a cold spot is numerically investigated by two-dimensional hybrid thermal lattice Boltzmann (LB) model based on the Shan-Chen pseudopotential LB model. After validating the present LB model, dropwise condensation over a cold spot as the nucleation region is simulated. The well-known power law for the growth of a single condensing droplet is demonstrated. Finally, the simulation of dropwise condensation considering the convection flow or not is carried out in the constant contact radius (CCR) mode. Using the CCR model, the effect of contact angle can be also investigated. The result of streamline field indicates that the forced convectional flow complicates the internal flow of droplet and main flow. The dragging force from main flow changes the size of two symmetric vortices inside the droplet. And the channel flow is also strongly influenced by the suction effect caused by condensation at the three phase contact line. By comparison, the heat transfer enhancement of the superimposed flow is not worth mentioning. The present study illustrates the mechanisms of dropwise condensation under forced convectional flow.
Numerical study of heat and mass flow in layered heat storage
Authors: Ziegler Bartosz , Mosiężny Jędrzej , Czyżewski Paweł
Published: November 2018

An analysis of argon gas flow in exemplary configuration of layered bed thermal energy storage is presented. The analysis incorporates URANS model with conjugate heat transfer between gas and solid storage core. The aim of this analysis was to identify key factors limiting exergy efficiency of this storage type and determine some details about storage transient behaviour. Three full cycles of storage loading and unloading having 17 hours physical time in total are simulated, with calculation of exergetic efficiency for each of the cycles. Conclusions regarding this storage type feasibility for indirect power storage in pumped heat systems are made.
Numerical analysis and simulation of the heat recovery from wastewater using heat exchanger
Authors: Gabor Timea , Tiuc Ancuta-Elena , Sur Ioana Monica , Badila Iulian Nicolae
Published: November 2018

The problem of global warming and the reduction of energy consumption have led to an evolutionary progress of research directed towards finding as many solutions as possible to these environmental issues. Firstly, this paper presents the background information on the role of wastewater as a source of heat for the future. Next, the paper includes the analysis elements that define a system for recovering thermal energy from wastewater. The main objective was to identify the parameters that determine the heat transfer. It has started from a conceptual model of the technological system that involves inputs and outputs characterized by technological, physical-chemical, measurable or imposed properties. In the second part this paper presents a numerical model elaborated for the analysis and simulation of the main physical processes, the mass and heat transfer, which underlie the operation of the heat pipe heat exchangers (HPHE). The numerical simulation of heat and mass transfer in the HPHE is computed by using Delphi 7 solver program. This program contained a series of sub-programs for the meshing of the field occupied by the HPHE, another subprogram for solving the meshing equations and the third for post processing. The design of HPHE is the key to provide a heat exchanger system to work proficient as expected. Finally, the result is used to optimize and improving heat recovery systems of the increasing demand for energy efficiency in residential buildings or industry.
Numerical analysis of flow in a modular heat exchanger used in food industrial plants
Authors: Judt Wojciech , Bartoszewicz Jarosław
Published: November 2018

In the article is proposed a construction of modular cross-flow heat exchanger. This construction can be used in food industrial plants for example to heating a palm oil for a chips production. The second possibility to make use of that heat exchanger in a food industrial plants will be a heating of a worn out rape oil after a technological process for a improvement of effective utilization in oil boiler. The main advantage of modular heat exchangers is the possibility of simple adjustment of heating power dependent on demand. It is possible by valve system, which can cut off subsequent sections of the heat exchanger from the plant when heat requirement is decreasing. During a numerical simulation was demonstrated, that an exhaust gases flow in a heat exchanger is not homogenous. In numerical analysis was obtained a real flow velocity distribution and temperature distribution for a full geometry of the designed object and for two subsequent section of the heat exchanger.
Prediction or hydraulic performance of shell-and-tube heat exchanger: comparison of 1D and CFD-porous media approaches
Authors: Kalioudjoglou Loïck , Bonneau Clément , Melot Vincent , Auvity Bruno , Josset Christophe , Merriaux Yoann
Published: November 2018

The present paper deals with Heat Exchanger sizing methods and offers a comparison between two of them: 1D global method and CFD porous media method. Following Prithiviraj et al. work [1], new developments are based on recent knowledge acquired on porous media, using a coupling strategy of a three-dimensional commercial code with an in-house code library. The distributed hydraulic resistance concept and the numerical model are briefly described and confronted with pressure drop measurements from an experimental E-type STHE setup (shell-and-tube heat exchanger) from the literature. The present paper will put into perspective capabilities and limits of each method with needs for heat exchanger rating. Flow rate repartition is calculated with CFD-porous media using Tinker’s current approach. This new analysis provides a complete comparison with 1D global method. It also reveals the major impact of leakage flow rate between baffle and tubes. The numerical estimation of pressure losses, consistent with experimental measurements of Halle et al. [2], implies that our future work will include thermal performance characterization and geometrical optimization.
Theoretical modeling and experimental study of auxiliary concrete accumulator for solar heating systems
Authors: Sacharczuk Jacek , Taler Dawid
Published: November 2018

This article presents the issue of the use of the control-volume finite-elements method (CVFEM) to solve transient heat conduction problem in the ceramic or concrete structure of heat storage system. The system can be used as auxiliary storage in solar based domestic hot water (DHW) and heating installations. The storage system consists of modular symmetric components forming parallel air channels. The modular design and symmetry of cross section enables to build a simple numerical model using a coarse mesh of finite volumes. It allows solving the problem using the simple algorithm. Analyzed method of modeling provides a short computation time while maintaining high calculation accuracy.
Numerical and experimental study of flow distribution in tubular space of fin-and-tube heat exchanger with modified inlet manifold
Authors: Stelmach Tomasz
Published: November 2018

This paper presents the experimental and numerical investigation of flow distribution in the tubular space of cross-flow fin-and-tube heat exchanger. The tube bundle with two rows arranged in staggered formation is considered. A modified heat exchanged manifold, with inlet nozzle pipe located asymmetrically is considered. The outlet nozzle pipe is located in the middle of the outlet manifold, with a standard shape. An experimental stand allows one to investigate the volumetric flow rate in heat exchanger tubular space using the ultrasonic flowmeters. Various inlet mass flow rate i.e. 3 m3/h, 4 m3/h and 5 m3/h are considered. The experimental results are compared with CFD simulation performed in ANSYS CFX program using the SSG Reynolds Stress turbulence model. A relatively good agreement is found for tube Re numbers varied from 1800 to 3100.