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Принятие комплекса законодательных актов в сфере энергетики, объединяемых термином Energiewende , существенно изменило структуру потребления энергии в Германии: в настоящее время наи-большую долю в ней занимает зеленая энергия, выработанная за счет использования ветра, солнца, воды и биомассы. Подобные изменения, безусловно, можно расценивать как успех. Однако, одновременно с целена-правленным изменением структуры производства и потребления энергии в Германии возникли определенные социально-политические, экономические и юридические проблемы, требующие тщательного изучения. Дискус-сионным является вопрос о соответствии целей и предлагаемых мер их достижения, в частности, в отношении бесперебойности энергообеспечения, расширения электрических сетей, совершенствования подхода к ценооб-разованию, экологических последствий с учетом курса на тотальное расширение производства энергии за счет возобновляемых источников. Актуальными для Германии и затрагивающими энергетическую политику России являются вопросы ускоренного сворачивания ядерной энергетики и легитимности национального курса Герма-нии на продвижение зеленой энергетики в контексте интеграции с Европейским энергетическим рынком. В статье выполнен анализ указанного комплекса проблем и охарактеризована роль национального законода-тельства Германии в их решении. from wind, solar, water and biomass now provides the largest contribution to the total electricity consumption. In this respect, Energiewende can be regarded as an overall success. But in parallel to this scenario, a critical discourse has evolved concerning socio-political, economic and legal issues. The congruence of objectives and measures for example, in regards to ensuring security of supply, expansion of electricity networks, development of electricity price and envi-ronmental consequences in the course of expansion of electricity generation from renewable sources is the main focus of socio-political and economic discussions. Accelerated phase-out of nuclear energy and constitutional disputes regarding the legality of national orientation of the promotional scheme for green electricity in respect to the integration of German electricity sector in the European internal market for energy are in the centre of the debate and have a remarkable impact on the energy policy in Russia as well. Against this background, present article examines the con-tribution of German Energiewende to the resolution of complex challenges of the developed industrial society. №4 (226) (2017)

This research aim is to develop a method for modeling the conditions for the critical hydraulic impacts emergence on thermal and nuclear power plants’ pipeline systems pressure pumps departing from the general provisions of the heat and hydrodynamic instability theory. On the developed method basis, the conditions giving rise to the reliability-critical hydraulic impacts emergence on pumps for the thermal and nuclear power plants’ typical pipeline system have been determined. With the flow characteristic minimum allowable (critical) sensitivity, the flow velocity fluctuations amplitude reaches critical values at which the pumps working elements’ failure occurs. The critical hydraulic impacts emergence corresponds to the transition of the vibrational heat-hydrodynamic instability into an aperiodic one. As research revealed, a highly promising approach as to the preventing the critical hydraulic impacts related to the foreground use of pumps having the most sensitive consumption (at supply network) performance (while other technical characteristics corresponding to that parameter). The research novelty refers to the suggested method elaborated by the authors’ team, which, in contrast to traditional approaches, is efficient in determining the pump hydraulic impact occurrence conditions when the vibrational heat-hydrodynamic instability transition to the aperiodic instability.

В работе представлены результаты энергоаудита, проведенного на семи объектах в 2013 году сотрудниками Института Энергетики АНМ, которые являются авторизированными в электрои теплоэнергетике. Четыре энергоаудита относятся к анализу эффективности энергопотребления в зданиях, три к энергообследованию систем уличного и внешнего освещения. Для каждой организации были выявлены основные проблемы, которые ведут к повышенным потреблениям энергии и были предложены различные меры способствующие снижению энергозатрат, а также снижению выбросов СО2. Расшифровано понятие энергоаудита, дана характеристика мероприятиям, выполняемым в процессе его проведения. Описано использованное для проведения работ оборудование. Дан анализ характерным проблемам по каждому объекту, а также возможные способы их решения. Определены необходимые инвестиции для внедрения предлагаемых мер по энергоэффективности. Оценен экономический эффект и срок окупаемости как для каждого объекта, так и по всем объектам в целом.

În lucrare se analizează structurile existente de celulele fotovoltaice, parametrii acestora, ţinând cont de durata de viaţă, randament şi cost. S-a stabilit, că randamentul acestora variază de la unităţi de procent până la câteva zeci de procent. Cele cu randament înalt peste (20%) au un cost de 5-10 ori mai mare ca cele cu randament de până la 15%. Pe piaţa Republicii Moldova se comercializează numai panouri cu celule fotovoltaice de randament până la 15%. Durata de viaţă este cuprinsă între 20 şi 30 de ani, iar după 15 ani de viaţă randamentul celulelor solare se reduce cu 10%. În plus, acesta mai depinde şi de temperatura mediului şi se reduce cu aproximativ 0,3% la fiecare grad, parametrii tehnici fiind daţi pentru temperatura de 25oC. Totodată, se menţionează că în timpul apropiat se va pune accentul pe celulele solare organice care în prezent au un randament la nivel de 5-7%. Pentru a crea o nouă generaţie de celule solare cea mai promiţătoare este considerată construcţia, în care stratul de siliciu nanocristalin este încorporat între straturi subţiri de siliciu amorf. Aceasta oferă o eficienţă foarte mare a bateriei, în plus, ea elimină necesitatea de substraturi masive din monocristale de siliciu, consumul acestui material scump se reduce.

The work is devoted to the study of heat transfer in channels with a longitudinal pressure gradient. The aim of the work is to develop methods for increasing the heat transfer intensity in channels with a longitudinal pressure gradient. The goal was achieved by developing the original design of the surface intensifier, made in the form of a horseshoe-shaped dimples, as well as by conducting heat transfer studies in the channel with a longitudinal pressure gradient and dimples of various geometries and locations. It was found that a numerical solution using the k-epsilon turbulence model shows not sufficiently stable results, including the values of local heat transfer coefficients can exceed 2 ... 2.5 times their actual values for a single dimple. Moreover, the use of the k-w-sst turbulence model shows more stable results. The most significant results obtained in the work are as follows: it was revealed that the use of holes, their geometry and location have a significant effect on the heat transfer intensity in a channel with a longitudinal pressure gradient; the design of the original horseshoe-shaped dimples has been developed, the use of which allows to intensify heat transfer by 13 ... 47% depending on the Reynolds number when they are arranged in three rows in the corridor order compared to staggered hemispherical dimples; when comparing the efficiency of using the developed dimples with hemispherical holes installed in three rows in the corridor order, the heat transfer increased by 21 ... 51% when the Reynolds number changed from 3000 to 15000.

A significant number of domestic and industrial boilers are in operation in Ukraine. Nitrogen oxides are the most dangerous among all combustion products that pollute the atmosphere, therefore, one should take some measures for decreasing the formation of nitrogen oxides during combustion. The studies were carried out at the boilers of low power (100 kW) with a tubular radiator and an open end. The studies in the furnaces of industrial steam boilers having a tubular radiator with a closed end have not been done. The numerical study results of the gaseous fuel combustion processes in the furnace of a DE-10/14 steam water-tube boiler are presented. The fuel-air mixture is formed by premixing the 15% part of the air with a primary burner twist factor n=2.4 and a secondary burner twist factor n=1.6, and an air excess factor αв=10. As a result of the studies, the temperature and velocity distributions of gases in the combustion chamber, the density of heat flows on the screen tubular surfaces, and the concentrations of the combustion components were determined. Flue gas recirculation in the volume of 80-100% is provided, and the reversible movement of combustion products towards the combustion front provides a reduction in the concentration of nitrogen oxides up to 123-125 mg/m3 at the furnace outlet. Disadvantages are the following: the formation of stagnant zones near the end of the secondary radiator. The optimum diameter of the tubular radiator equals to two burners diameters and tubular radiator is located at a distance of one meter from the burner cutoff.

The natural phenomenon of a tornado, known for its destructive power, is an object of study of many scientists. The available part of the data of field observations of this natural phenomenon is systematized and collected in the so-called Fujita scale. In particular, it indicates the width of the fracture band for tornadoes of different intensity, and only the values of the maximum wind speed are given from the gas dynamic parameters. Bautin S.P. proposed and justified the scheme of occurrence and functioning of natural ascending swirling flows of the tornado and tropical cyclones. Based on both this scheme and the data of the Fujita scale, the external radii of air inflow in the near-bottom parts of tornadoes of various intensities are established and the gas dynamic parameters of these flows are calculated. It turned out that in the case of the lowest intensity from the Fujita scale, the kinetic energy of the rotational motion of the air is half of the entire kinetic energy of the flow in the bottom part. As tornado intensity increases, the kinetic energy of rotational motion becomes the more prominent part of the total kinetic energy of the flow. In this paper, given the Fujita value of the width of the destruction zone for all tornadoes along with the two external radii of air inflow into the bottom part of the tornado are established as rin1 and rin2. The first of these radii, namely rin1 , denotes the radius at which the kinetic energy of the rotational motion of the constructed stream is half of all the kinetic energy of this stream. The second one denoted as rin2, is the radius at which the kinetic energy of the entire stream becomes equal to the kinetic energy of the weakest destructive tornado. Knowing the values of these radii allows reliable predicting the origin of the tornado. В настоящей работе при заданном в таблице Фудзиты значении ширины полосы разрушений для всех торнадо установлены два внешних радиуса притока воздуха в придонную часть торнадо: in1 и rin2. Первый из этих радиусов in1 такой, что кинетическая энергия вращательного движения построенного потока составляет половину всей его кинетической энергии. При втором радиусе rin2 кинетическая энергия всего потока становится равной кинетической энергии самого слабого торнадо, при котором имеют место разрушения. Знание значений этих радиусов позволит более надежно прогнозировать возникновение торнадо. №5(23) (2018)

The purpose of this work is the theoretical substantiation and development of a practical method for calculating the exchange fund of electrical equipment of an industrial enterprise. The purpose is achieved through the use of separate methods of queuing theory if the flow of applications for repairs and restoration are the simplest. It is confirmed by the results of statistical studies. Therefore, for the mathematical description of the repair problem the authors use the scheme [Mm; Ms; n], which corresponds to the process of death and reproduction. As a criterion for optimizing the exchange fund of electrical equipment it is proposed to use the zero probability waiting for the replacement of a faulty electrical component with a working from the exchange fund. For the case of the simplest flow of applications for service, the authors suggest to use the Peck and Hazelwood tables, which significantly simplify the calculation of the exchange fund for known failure rates and electrical equipment recoveries. For practical use of the proposed method, the authors have developed convenient forms for presenting initial data for calculating the exchange fund, and it is proposed to present the results of calculations in the form of several options for the optimal number of electrical equipment in the exchange fund depending on the accepted level of zero expectation probability, the number of elements from the exchange fund and their recovery time. The proposed method will optimize the exchange fund of electrical equipment and reduce the cost of its formation.