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Almost every person is using batteries on daily base. From small appliances to larger power tools to large stores and electric cars. Requirements for lithium ion batteries getting higher every year either from view of capacity, cycle number, or high current flow. With higher requirements is also the safety of batteries connected. Lithium ion batteries need to work safely and reliably at higher temperatures and loads. From flame safety view is necessary non-flammability of all battery parts. One of potential risk is organic solvents based electrolyte. This paper focus on influence, of flame-retardant additive in electrolyte, and its compatibility with the negative electrode in lithium ion battery. Several phosphorous-based flame retardants were tested and their influence on capacity of negative electrode was determined.

Целью исследования является разработка новой конструкции саморегулируемого водяного аккумулятора теплоты с температурной стратификацией воды, исключающей перемешивание греющего и нагреваемого теплоносителей, поступающих в аккумулятор из контуров зарядки и разрядки на основе естественного расслоения воды в баке под влиянием объемных (архимедовых) сил в условиях принудительной циркуляции теплоносителя. На основе анализа мирового опыта разработки конструкций водяных аккумуляторов теплоты с температурной стратификацией воды и устойчивости стратифицированного (расслоенного) течения теплоносителя в объёме аккумулятора предложена новая конструкция саморегулируемого водяного аккумулятора. Рассмотрены преимущества использования саморегулирующихся стратификационных водяных тепловых аккумуляторов в системах солнечного теплоснабжения. Показано, что использование стратификации для кратковременного и долгосрочного накопления тепла приводит к увеличению использования солнечного тепла на 15-20% по сравнению с полностью перемешивающимися аккумуляторами. В системах горячего водоснабжения эти аккумуляторы могут обеспечить более раннюю подготовку горячей воды с требуемой температурой для потребителей.

A wheel loader is representative construction machinery that is designed to load material in off-road applications. The vehicle moves back and forth in the loading process, showing great hydraulic hybridization potential. The research target in this study is a compact wheel loader. By adding hydraulic energy storage device – hydraulic accumulator, it is turned into a series hydraulic hybrid. In this paper the system modeling and controllers design of series hydraulic hybrid wheel loader were illustrated. A tunable energy management strategy has been proposed and studied. By changing the hybrid weight factor in the strategy, the powertrain hybridization degree was adjusted without any additional hardware. This study shows that higher use of the hydraulic accumulator power indicates a higher degree of hydraulic hybridization. Results show that the series hydraulic hybrid wheel loader has a fuel saving of 18.9% compared to a hydrostatic wheel loader in the short loading cycle. Studies had also been conducted to show the trade-off between the fuel consumption and the vehicle performance with different hybridization degrees.

The direct steam generation (DSG) solar power system using two stage accumulators and cascade steam-organic Rankine cycle (RC-ORC) has remarkably enlarged storage capacity. It can facilitate stable power generation and address the challenges of conventional DSG systems. Regenerator is generally an issue worthy of discussion in organic Rankine cycle (ORC) systems. However, its influence on the newly proposed DSG system has not been investigated yet and is expected to be appreciable. Introducing a regenerator affects not only the ORC efficiency, RC-ORC efficiency, heat exchanger area, but also heat storage capacity, discharge duration, discharge efficiency, aperture area of collectors and the net profit ( Δ P ). Detailed performance comparison between the DSG systems without/with regenerator is carried out in this paper. The results indicate that at a given power output, aperture area is reduced by the regenerator especially for MM, R365mfc and pentane due to the increment in ORC, RC-ORC and discharge efficiencies, as well as the decrement in heat input. Discharge duration is shortened by 0.01–1.78 h depending on ORC fluids. R365mfc exhibits the maximum Δ P (4.19 ∼ 6.48 million USD), followed by MM and pentane. On the contrary, Δ P is negative for benzene (−5.61 ∼ -4.31 million USD).

Reduction of energy consumption in technological processes of cooling and storage milk on farms is urgent task.(Research purpose) The research purpose is in reducing the energy intensity of the milk cooling process on farms while maintaining its quality.(Materials and methods) The authors conducted research to improve existing and create new smart combined cooling systems based on the rational use of natural and artificial cold sources with means of its accumulation and environmentally friendly coolants with low freezing point.(Results and discussion) The authors have found the dependence of the amount of energy that can be used for cooling and storage of milk and dispersed into the environment on the potential of natural cold of the area and the location of the technological object. The article presents a methodology for assessing the potential of natural cold for different regions of Russia. According to the methodology, authors calculated the values of the ice storage capacities for dairy farms with different livestock and annual milk yield. The article presents the diagram of electric energy savings when using natural cold to cooling milk on farms of 400 heads with a yield of 5000 liters in different climatic regions of Russia. Significant energy savings can be obtained through the use of combined accumulators of natural and artificial cold using environmentally friendly coolants with low freezing point and ground ice storage, in which the freezing of soil and water is carried out due to the ground cooling thermal installation with twophase thermosyphons.(Conclusions) The use of smart combined milk cooling systems on farms on the basis of sources of natural and artificial cold with means of its accumulation and environmentally friendly coolants with low freezing point allows to reduce energy consumption in 1.5-3 times at preservation of its quality. At the same time, such systems in various configurations can be effectively used in all agroclimatic regions of the country.

The hydrogen sorption characteristics of La1–xCexNi5 alloys (x = 0, 0.1, 0.2, 0.25, 0.5) were studied in the temperature range 298–363 K. The optimal compositions of intermetallic compounds were determined for use as hydrogen sorbents in reusable accumulators: compounds La0.9Ce0.1Ni5 and La0.8Ce0.2Ni5. Based on them, a metal hydride hydrogen accumulator was designed and manufactured and its technical and operational characteristics were found. The developed devices are proposed to be applied in electric energy storage systems using hydrogen as an energy carrier.

Elevator has been the most critical equipment for vertical transportation and one of the largest energy consumption sources in buildings. The main cause of energy waste in elevator is the dissipation of the energy regenerated by the motor. To achieve energy saving, this article proposes an electro-hydraulic hybrid driving elevator system. With an auxiliary hydraulic system, the energy generated by the motor can be stored in the form of hydraulic accumulator pressure, which can be reused to assist motor start in the form of supporting torque. In addition, due to the additional torque provided by the hydraulic system, elevator safety can be enhanced. Simulation results have been obtained, demonstrating that large amount of energy can be saved with the proposed system. Field test results with elevator in a real building environment are also presented to verify the efficacy of the proposed idea.

Due to the fact that any type of aerospace vessel needs energy, and in the future, this energy must be nuclear and obtained by fusion, not by fission, this paper presents shortly a method by which nuclear fusion can be more easily achieved on an industrial scale. On the other hand, normal aircraft will have to be electrically operated with modern electric motors in the future, which will be able to be energized from modern accumulators which in turn will be charged with energy obtained by burning hydrogen. Hydrogen has the advantage of being obtainable by various methods on an industrial scale, sustainable, and of ensuring economic combustion and without pollution. The paper presents ways to extract hydrogen directly from water, including ones made by the authors of the paper over time, but also the possibility of using nuclear energy extracted by fusion also from hydrogen (its ionic isotopes, deuteron or Triton).

The mechanical molecular spring isolator (MMSI) presents the characteristics of high-static-low-dynamic-stiffness to isolate the low-frequency vibration of a heavy payload. An MMSI consists of a piston-cylinder container full of the liquid and some hydraulic spring accumulators. This paper focuses on a particular type of the MMSI that all hydraulic spring accumulators applying the conventional coil spring are identical. In the beginning, the MMSI stiffness model is modelled and the influences of critical parameters on the stiffness property are studied. The MMSI presents a piecewise linear stiffness property. The averaging method is applied to determine the primary resonance response, and the energy transmissibility is adopted to estimate the vibration isolation performance. A jump phenomenon is inevitable to be occurred around the resonance region. The jump avoidance is a critical design part of the MMSI isolation system. On the other hand, based on the stiffness model, it reveals that any stiffness of the coil spring or any size of the accumulator in the MMSI will be able to achieve the same desired stiffness property. The most significant difference between all solutions depends on the coil spring lateral stability. The coil spring lateral stability magnitude is defined as the ratio of the deflection to the buckling deflection to evaluate the quality of each solution. Then, the fundamental design criterion on the MMSI based on jump avoidance and the coil spring lateral stability is established.

Застосування гідроакумуляторів значно зменшує частоту включень насосів, суттєво збільшуючи ресурс їх роботи. Основними факторами, що впливають на регулювальні параметри гідроакумуляторів, є характеристики газових процесів, що відбуваються під час стиснення та розширення газового середовища. Удосконалено методику експериментального визначення інтегральних регулювальних характеристик гідроакумулятора мембранного типу, а також експериментального визначення показника політропи газових процесів в гідроакумуляторі шляхом одночасного визначення в режимі онлайн зміни тиску повітря в гідроакумуляторі та об’єму витісненої з гідроакумулятора рідини. Виготовлено стенд для експериментального дослідження перехідних газових процесів у баці гідроакумулятора мембранного типу. Експериментальні залежності абсолютного тиску повітря в гідроакумуляторі від його об’єму з достатньою для практики точністю можуть бути описані найпростішими степеневими залежностями, тобто описані за моделлю ідеального газу. Для чотирьох послідовних циклів розрядки дослідного гідроакумулятора за незмінного ступеня відкриття запірно-регулювального пристрою на виході трубопроводу отримано відносно незначні, але систематичні зміни інтегральних регулювальних характеристик гідроакумулятора, а саме: збільшення регулювального об’єму на 6,0 % (від циклу № 1 до циклу № 4), зменшення часу розрядки гідроакумулятора на 3,6 % та збільшення середньої об’ємної витрати води на виході з гідроакумулятора на 10,0 %. Отримано систематичне зменшення для кожного наступного циклу розрядки значення показника політропи газового процесу від 2,07 для циклу № 1 до 1,945 для циклу № 4. Отримані систематичні зміни пояснено наявністю перехідних термодинамічних процесів у газовому середовищі гідроакумулятора до встановлення динамічної рівноваги із зовнішнім середовищем. Main factors influencing the regulating parameters of gas-charged hydraulic accumulators are thermodynamic processes occurring during the gas compression and expansion. Method of experimental determination of the polytropic index of gas processes in the hydraulic accumulator is improved. An experimental setup was installed for the investigation of integral regulating parameters of the bladder-type hydraulic accumulator. The parameters of non-stationary expansion of the air in the accumulator's shell during its operation with a simple short pipeline are experimentally investigated and analyzed. Polytropic index was regularly decreasing in the cycles #1 to #4 from 2.07 to 1.95. Storage volume of hydraulic accumulator, at the same time, increased on 6.0% while discharge time decreased on 3.6 %. Obtained experimental trends are explained by the transient thermodynamic processes in the gas inside the hydraulic accumulator before the dynamic equilibrium with the external environment is established.

Phase coherent, frequency hopping direct digital synthesizer (DDS) and Type-II phase locked loop (PLL) circuits are presented in this paper. The proposed approach eliminates the memory effects of prior frequency states in the phase (DDS) and fractional (PLL) accumulators by employing a master accumulator with a fixed increment and multiplying its output to generate the appropriate phase and fractional outputs. This approach allows for an arbitrary sequence of frequency hops, since it is not based on multiple simultaneous accumulators to store phase. We present phase coherent topologies for standard and parallelized DDS circuits, a fractional-N PLL and a multistage sigma-delta modulator (MASH)-111 fractional-N PLL, along with mathematical analysis showing phase coherency. We also present measured results of parallelized DDS and MASH-111 fractional-N PLL hardware.

The heaving buoy wave energy device is popular for wave conditions with small wave heights and short periods. This paper presents the design of a wave energy converter composed of a gyro buoy, a hydraulic power take-off, and an electricity generation system. The energy accumulators are used to improve the output power with different control strategies. The quantity relations between each component are established using theoretical methods. The simulation model describes the energy conversion and calculates the operation time, energy capacity, and output power of the device under different initial pressures, release pressures, and electric resistances. As a result, the capacity is determined by the electronic load, and the maximum output power can be obtained when the accumulators are turned on and off at the same time. This study investigates the factors influencing the electric energy production and can be used to guide the optimization of this type of device.

The aim in the present work is to simulate accident scenarios of AP1000 during the small-break loss-of-coolant accident (SBLOCA) and investigate the performance and behavior of automatic depressurization system (ADS) during accidents by using MIDAC (The Module In-vessel Degradation severe accident Analysis Code). Four types of accidents with different hypothetical conditions were analyzed in this study. The impact on the thermal-hydraulic of the reactor coolant system (RCS), the passive core cooling system and core degradation was researched by comparing these types. The results show that the RCS depressurization becomes faster, the core makeup tanks (CMT) and accumulators (ACC) are activated earlier and the effect of gravity water injection is more obvious along with more ADS valves open. The open of the only ADS1-3 can't stop the core degradation on the basis of the first type of the accident. The open of ADS1-3 has a great impact on the injection time of ACC and CMT. The core can remain intact for a long time and the core degradation can be prevent by the open of ADS-4. The all results are significant and meaningful to understand the performance and behavior of the ADS during the typical SBLOCA. Keywords: MIDAC, ADS, SBLOCA, Thermal-hydraulic, Core degradation

In this paper, a novel fuzzy Proportion Integration Differentiation (PID) controller is proposed to extract the optimal energy from wind for a hydraulic offshore wind turbine. Firstly, in order to calculate the theoretical power, an adaptive neuro‐fuzzy inference system (ANFIS) is designed for wind speed evaluation, in which the input parameters include rotor speed, rotor torque, and pitch angle, and the output parameter is the estimated wind speed. Then, the optimal power coefficient is achieved by controlling the hydraulic pump torque to tracking the optimal rotor speed, and a fuzzy PID is designed to adjust the pump displacement and to obtain the optimal hydraulic pump torque. Furthermore, aiming to meet the various output power demand, a hydraulic accumulator is utilized for storing the excess energy, and a PID controller is designed for distributing the hydraulic energy between the accumulator and the Pelton turbine. Finally, the performance of proposed controls system are confirmed by two case simulations on a 5 MW hydraulic offshore wind turbine. The simulation results show that, compared with the conventional control methods (fuzzy logical and PID controller) used in electro‐hydraulic servo system, the fuzzy PID controller can provide the better tracking effect with a faster speed and a minimal steady‐state oscillation. Moreover, with the use of a hydraulic accumulator, all the power fluctuations from the wind speed disturbances are damped out and the output power become controllable.

PCMs (phase change materials) applied in heat storage technology are on the one hand characterised by relatively large specific heat capacity, and on the other hand by relatively low thermal conductivity (e.g. 0.2 W·m−1·K−1) for paraffin), which prolongs the charging/discharging cycles of heat accumulators based on such materials. In order to improve the heat transfer within PCMs, spatially shaped pin-fin metal alloy structures are being developed that have been immersed in the PCM material. Pin-fin metallic structures can be manufactured via investment casting technology. The 3D structures produced using this technique can be modified and adjusted in order to improve the heat transfer parameters (heat conductivity, specific heat transfer area). For this study, complex metal alloy pin-fin structures were immersed in paraffin, and an experimental test stand was built in order to examine the heat transfer characteristics of composite PCMs with pin-fin metal structures. Multiple heating/cooling cycles confirmed the enhanced transfer of heat inside the heat storage unit and allowed us to ascertain the decreased temperature gradient within the heat accumulator. The heat transfer phenomenon was simulated to show heating and melting course nearby metal inserts and confirm the beneficial influence of the applied pin-fin geometry, that can be further optimized. The thermal behaviour of the PCM, tested with DSC and TGA analysis, was used as an input for the simulation.

In this article, the heavy earth moving machinery like hydraulic excavator used in the construction and mining industries has been taken into consideration. Most of the heavy earth moving machineries used in these industries are mobile with engine as the main source of power. The work deals with two different hydraulic circuits: first the proposed one and second the conventional one, and both are studied at laboratory scale, which resembles the circuit of the hydraulic excavator. In the hydraulic circuit, out of the three hydraulic linear actuators, two are connected with hydro-pneumatic accumulators and one hydro-motor is also taken into consideration, which resembles the boom, arm, bucket and swing motor, respectively. The idea behind the proposed circuit is to store substantial potential energy during downward movement of the two linear actuators in the accumulators, which resembles the boom and arm cylinder of the excavator. The stored energy is used for upward motion of the two actuators without utilizing any energy from the main pump. For the devised strategy, MATLAB/Simulink environment has been utilized for developing the simulation model and the same has been validated with the experimental data with reasonable accuracy. The effect of accumulator volume and pre-charge pressure has been studied for optimization of the accumulator size on the validated simulation model. This concept helps in saving 14.06% energy than its conventional counterpart which does not have the energy storage elements. The linear position control of the boom and the arm actuator in the proposed circuit have been accomplished using proportional–integral–derivative control and pressure-compensated proportional flow control valve and have been achieved with reasonably accuracy.

We propose the use of the conventional energy storage component, i.e., capacitor, in the kinetic-powered wearable IoTs as the sensor to detect human activities. Since activities accumulate energy in the capacitor at different rates, the charging rate of the capacitor can be used to detect the activities. The key advantage of the proposed capacitor-based activity sensing mechanism, called CapSense, is that it obviates the need for sampling the motion signal at a high rate, and thus, significantly reduces power consumption of the wearable device. The challenge we face is that capacitors are inherently non-linear energy accumulators, which leads to significant variations in the charging rates. We solve this problem by jointly configuring the parameters of the capacitor and the associated energy harvesting circuits, which allows us to operate in the charging cycles that are approximately linear. We design and implement a kinetic-powered shoe and conduct experiments with 10 subjects. Our results show that CapSense can classify five different daily activities with 95% accuracy while consuming 57% less system power compared to conventional motion-sensor-based approaches.

A dynamic programming optimization algorithm has been applied on a transit bus model in MATLAB in order to assess the fuel economy improvement potential by implementing a hydraulic hybrid powertrain system. The numerical model parameters have been calibrated using experimental data obtained on a Belgrade’s public transport bus. This experiment also provided the representative driving cycle on which to conduct simulation analyses. Various functional parameters of a hydraulic hybrid system have been evaluated for obtaining the best possible fuel economy. Dynamic programming optimization runs have been completed for various hydraulic accumulator sizes, preload values and accumulator foam quantities. It has been shown that a fuel economy improvement of 28% can be achieved by implementing such a system. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR35042: Research and Development of Alternative Fuel and Drive Systems for Urban Buses and Refuse Vehicles with Regard to the Improvements of Energy Efficiency and Environmental Characteristics]

The paper considers issues of increasing capacity on «bottleneck» sections of direct current railways by means of application of electric power accumulators. Selection of electric power accumulators location is carried out with the consideration for grading of track on a section, specific recuperation, dominance of traffic type, rate of electric rolling stops, mode of feeding of intersubstational zones. When determining power consumption and capacity of electric power accumulators a depth of discharge that affects a service life and a state of charge graph that depends on a selected characteristic of charging rate are considered. The procedure of assessing the influence of electric power accumulator operation on capacity is considered on the example of one of the railway sections.

The paper seeks to increase efficiency of operational control of distributed technological heat and steam supply networks in metallurgical production complexes based on dynamic macro-modeling of network modes under structural switching and sharply variable loads. It suggests solving problems of resource flows stabilization in a technological network by solving the equations of inverse problems of network dynamics and using calculated contours of stream disturbance rearrangement. It is advisable to construct flow disturbance parading algorithms in a process network using inverse models of path dynamics of input control streams to input nodes of flow disturbances in the network. The paper presents a software macro model that allows modeling static and dynamic modes of steam and heat supply systems, control of charging and discharge processes of steam accumulators. The controlled parameter of the model is the steam pressure in the battery. The steam pressure in the accumulator is limited by means of a special pressure regulator, which is adjusted to a minimum of steam losses on the plug at its excess in the network. This software macro model allows modeling the operation of consumers with a sharply expressed variable load.

Traditional excavators driven by diesel engine have poor emissions and low energy efficiency. Pure electric driven excavators have high cost and limited endurance. Therefore, at present, hybrid power train system is an ideal candidate for excavators to realize energy-saving and emission reduction. In this paper, a novel series hybrid hydraulic excavator based on electro-hydraulic composite energy storage, which provides the average power of the system through the diesel engine, and the battery and accumulator are used as the intermediate energy storage devitalize the output current of the battery, and improve the service life of the battery, is proposed. Advantages of high energy density of battery and high power density of hydraulic accumulator are synthetically utilized. A 7-ton crawler excavator is taken as the research object, according to typical load spectrum, through analysis method and modeling method, and using dynamic programming (DP) to optimize the parameters of the novel series power train system. The control strategy of the power system is further studied, and the AMESim and Simlink co-simulation models of the transmission system is established to verify the feasibility of the system. At last, the experimental platform is built. Experiments are conducted to verify the effectiveness of the power train system.

A regenerative fuel cell (RFC) is a hydrogen accumulator which is charged via an electrolyzer (electricity conversion into H2) and discharged via the fuel cell (H2 conversion into electricity), where the storage media is pressurized hydrogen. The also generated oxygen is mostly not stored in terrestrial applications. There are discrete RFCs (DRFC) consisting of two separate stacks (electrolyzer and fuel cell) and unitized RFCs (URFC) with one single stack working during charge in electrolysis mode and during discharge in fuel cell mode. URFCs show a high specific energy up to 1500 Wh kg−1. Furthermore, it is possible to optimize the power and energy of the system independently, which is important for seasonal storage of larger amounts of energy. In contrast to conventional electrochemical accumulators the discharge power of RFCs is unaffected by the state-of-charge of the system. But unfortunately, due to the long conversion chain with associated losses, RFCs generally have low levels of efficiency compared to conventional electrochemical accumulators. The high specific energy of URFCs makes the system interesting for niche applications in military and space areas where efficiency and related costs are not primary parameters. For civil terrestrial applications, however, costs and electrical efficiency are mostly primary parameters. DRFCs are preferred since the individual stacks (EL, FC) can be better optimized. However, for the time being, there are existing no commercial applications of RFCs, as they are not really competitive, especially not with electrochemical accumulators. In the future could be electricity storage with RFCs possible in off-grid or island applications in which a high level of autonomy is required but also in grid application with high share of renewables to stabilized power supply. In a broader sense are power-to-gas storage systems identically with DRFCs. Power-to-gas technologies and therefore also electrolyzers currently are developing strongly which will decreases the costs and increases the efficiency of RFC as well. The RFC technology is in the moment proton exchange membranes based, but they are relatively costly caused by use of platin group metal catalysts. Alkaline-RFCs could reduce the cost by using non-platin group metal catalysts. Because Alkaline–RFCs show an unsatisfactory performance and poor cyclability, therefore, the development is still in an initial stage. The efficiency of PEM-RFCs (URFC max. 35%, DRFC max. 40%) is relatively low. Higher efficiencies, however, show SO-RFCs. SO-URFCs already reach today in an early development state ca. 45% efficiency and could be used also in terrestrial applications.

Тема выпускной квалификационной работы: «Расчет ГЕ САОЗ установки с ВВЭР-1500».Данная работа посвящена расчету и разработке конструкции ГЕ САОЗ для ЯЭУ с ВВЭР-1500. Задачи, которые решались в Ñ Ð¾Ð´Ðµ исследования:1. Проанализировать и обосновать ÑÑ ÐµÐ¼Ñƒ САОЗ.2. Провести расчет тепловой ÑÑ ÐµÐ¼Ñ‹ ЯЭУ.3. Провести тепловой расчет активной зоны.4. Провести расчет давления срабатывания ГЕ САОЗ.5. Разработать конструкцию ГЕ САОЗ.В работе приведены выбор ÑÑ ÐµÐ¼Ñ‹ и конструкции ГЕ САОЗ на основе Ñ€Ð°Ð·Ð»Ð¸Ñ‡Ð½Ñ‹Ñ Ð¿Ñ€Ð¾ÐµÐºÑ‚Ð¾Ð². Расчет тепловой ÑÑ ÐµÐ¼Ñ‹ ЯЭУ проведен методом математического моделирования с применением программного обеспечения САПР"United Cycle". Получены основные показатели тепловой экономичности АЭС. Определены геометрические Ñ Ð°Ñ€Ð°ÐºÑ‚ÐµÑ€Ð¸ÑÑ‚Ð¸ÐºÐ¸ реактора и параметры теплоносителя в реакторном контуре.Приведена методика расчета давления срабатывания ГЕ САОЗ в одноэлементном приближении. Проанализировано изменение параметров реакторного контура в процессе аварии с большой течью. Приведен прочностной расчет ГЕ САОЗ. На основе Ð¿Ð¾Ð»ÑƒÑ‡ÐµÐ½Ð½Ñ‹Ñ Ð´Ð°Ð½Ð½Ñ‹Ñ Ñ€Ð°Ð·Ñ€Ð°Ð±Ð¾Ñ‚Ð°Ð½Ð° конструкция ГЕ.Методика расчета гидроемкости, приведенная в работе, может быть использована для Ð°Ð½Ð°Ð»Ð¾Ð³Ð¸Ñ‡Ð½Ñ‹Ñ Ð¿Ñ€Ð¾ÐµÐºÑ‚Ð¾Ð² с реакторами типа ВВЭР., The subject of the graduate qualification work is « Calculation of the hydraulic accumulator of ECCS of the nuclear power plant with VVER-1500».This work is devoted to the calculation and development of the ECCS design for nuclear power plants with VVER-1500. Tasks that were solved during the study:1. Analyze and justify the ECCS scheme.2. Calculate the NPP thermal scheme.3. Conduct a thermal calculation of the core.4. Calculate the actuation pressure of the hydraulic accumulator of ECCS.5. Develop the design of hydraulic accumulator of ECCS.The work provides the choice of scheme and design of the hydraulic accumulator of ECCS based on various projects. The calculation of the NPP thermal scheme is carried out by the method of mathematical modeling using the CAD software "United Cycle". The main indicators of NPP thermal efficiency are obtained. The geometric characteristics of the reactor and the parameters of the coolant in the reactor circuit are determined.The method for calculating the actuation pressure of the hydraulic accumulator of ECCS in a single-element approximation is given. The change in the parameters of the reactor circuit during an accident with a large leak is analyzed. The strength calculation of the hydraulic accumulator of ECCS is given. Based on the data obtained, the design of the hydraulic accumulator is developed.The method for calculating the hydraulic accumulator given in the paper can be used for similar projects with other reactors.

Введение. Неотъемлемой частью агропромышленного комплекса является производство качественной сельскохозяйственной продукции, которое связано с механизацией технологических процессов. В настоящее время ведутся работы по поиску эффективных технических решений для совершенствования данных процессов. Одним из основных составляющих технологических процессов животноводства являются вакуум-откачные средства, предназначенные для дозирования, смешивания, транспортирования, сушки, кормораздачи, доения коров, переработки молока и других технологических процессов в сельском хозяйстве. Материалы и методы. Повышение эффективности пульсирующего струйного вакуум-откачного устройства, широко применяемое во всех отраслях промышленности и сельского хозяйства насоса, достигается без затрат механической энергии при достаточной простоте конструкции. Обоснование параметров струйного вакуум-откачного устройства, т. е. повышения коэффициента эжекции, производительности достигается преднамеренным нарушением стационарного режима течения материала. Пульсирующие течения транспортируемых материалов весьма многообразны, это связано с увеличенным количеством чисел подобия, определяющих их режим. Если для стационарного потока обычно используются приведенная скорость и число Рейнольдса, для пульсирующего течения к ним добавляются еще относительная частота и относительная амплитуда пульсаций. Результаты. В статье приведены результаты экспериментальных исследований, основными задачами которых было определение наиболее эффективных показателей работы эжекторов: степень повышения давления, коэффициент эжекции и геометрический параметр эжектора. В результате эксперимента были получены закономерности изменения производительности пульсирующего струйного вакуум-откачного устройства в зависимости от материала клапана и величины его пульсации. Выявлено, что для эжектора с пульсирующим движением активного потока рекомендуемым материалом клапана является металлический шарик, с частотой пульсации 90…100 мин-1. В результате применения предлагаемого эжектора с пульсирующим движением активного потока производительность транспортировки увеличится на 14.5 %. Заключение. Получены закономерности изменения производительности пульсирующего струйного вакуум-откачного устройства в зависимости от материала клапана и величины его пульсации. Выявлено, для эжектора с пульсирующим движением активного потока рекомендуемым материалом клапана является металлический шарик, с частотой пульсации 90…100 мин-1. В результате применения предлагаемого эжектора с пульсирующим движением активного потока производительность транспортировки увеличится на 14.5 %., Introduction. An integral part of the agro-industrial complex is the production of high-quality agricultural products, which is associated with the mechanization of technological processes. Currently, work is underway to find effective technical solutions to improve these processes. One of the main components of the technological processes of animal husbandry are vacuum pumping means designed for dosing, mixing, transportation, drying, feeding, milking cows, milk processing and other technological processes in agriculture. Materials and methods. Increasing the efficiency of the pulsating jet vacuum pumping device, widely used in all industries and agriculture of the pump, is achieved without the cost of mechanical energy with a sufficiently simple design. Justification of the parameters of the jet vacuum pumping device, i.e. increasing the ejection coefficient, productivity is achieve by a deliberate violation of the stationary flow of the material. Pulsating flows of transported materials are very diverse, this is due to the increased number of similarity numbers that determine their mode. If the reduced velocity and the Reynolds number are usually use for a stationary flow, for a pulsating flow, the relative frequency and relative amplitude of pulsations are also add to them. Results. The article presents the results of experimental studies, the main objectives of which were to determine the most effective indicators of ejectors: the degree of pressure increase, the ejection coefficient and the geometric parameter of the ejector. As a result of the experiment, patterns of changes in the performance of a pulsating jet vacuum pumping device were obtained depending on the valve material and the magnitude of its pulsation. It was reveal that for an ejector with a pulsating movement of the active flow, the recommended valve material is a metal ball, with a pulsation frequency of 90...100 min-1. As a result of the use of the proposed ejector with pulsating motion of the active flow, the transportation capacity will increase by 14,5 %. Conclusion. The regularities of changes in the performance of a pulsating jet vacuum pumping device depending on the valve material and the magnitude of its pulsation are obtain. It was reveal that for an ejector with a pulsating movement of the active flow, the recommended valve material is a metal ball, with a pulsation frequency of 90…100 min-1. As a result of the use of the proposed ejector with pulsating motion of the active flow, the transportation capacity will increase by 14,5 %.

This chapter describes the principle of operation and main features of hydraulic hybrids, including the typical architectures. it includes details of component design, both pump/motors (p/M) and accumulators, and describes modeling of components and integration into a complete vehicle system simulation. Case studies illustrate the approach to design and control of the parallel and series configuration, and summarize lessons learned through application of advanced simulations and optimization algorithms. Real-life applications and results achieved so far with prototypes or production vehicles are also presented. Section 16.5 is devoted to air-hybrids, their principle of operation, options regarding the configuration of the system and necessary engine modifications, and assessment of the fuel economy potential.

The article examines current three-zone and two-zone rates applied within the mechanisms of retail electricity market; the rates were developed for the consumers with prominent night load. The obtained results of the calculation made it possible to state that the use of thermal accumulators on the basis of calculations of the rates with separate formation of the components of electricity cost makes it possible to achieve the effect which on average is 32 % lower than the level of three-zone rates and 18 % lower than the twozone rates.The results lay emphasis on the effectiveness of use of thermal accumulators as tools of price-dependent electrical energy consumption management for residential users of Russia.

Modern thermal power is built based on three components: generation, transmission, and distribution of thermal energy. In this industry, another fourth element which was previously virtually absent is energy storage. Energy storage completely change our usual heat supply system. Heat storage is a serious factor in saving energy and improving environmental safety. The introduction of autonomous high and low potential heat storage systems is a real opportunity for the development of Intelligence Smart Grid heating systems. Therefore, the study of mobile heat storage batteries and the choice of methods for their design calculation and performance is an important task of modern science and technology. For this purpose, a study was conducted to determine the charging and discharge time of a mobile heat accumulator, depending on the type, volume, and temperature of the heat storage material. Types of thermal energy accumulation, classes of thermal accumulators, range of operating temperatures for a thermal accumulator were analyzed, design features of accumulators, operating time and methods of calculation of design parameters were considered. It is concluded that the method of calculation of MTA depends on the selected type of heat storage material. Although, phase transition materials have a higher heat storage density than liquid solutions, the design of liquid thermal batteries is much more attractive regarding technological, technical, and economic parameters. As a result of the study, the dependence of the MTA charging rate on the heat source power was obtained, the required amount of heat was determined, the average battery cooling time from the volume of the heat storage material, and the heat losses through the MTA body was analyzed. The results obtained must be taken into account when choosing the design and capacity of the battery.

Mobile machinery energy efficiency and emission pollution are the national and worldwide issues. This paper contributes in solving these problems by applying a speed variable power source. Unfortunately, almost all of the speed variable systems have the dynamic response problem when the motor starts with full load or heavy load. To address this problem, a hydraulic accumulator is used to balance the load of the power source for assisting starting of the motor and a matching method combined with speed and displacement control of the pump is proposed to improve the energy efficiency and dynamic performance simultaneously under different working conditions. Also, the power source/valve combined control strategy of an independent metering system is designed to realize flow matching of the whole system. Firstly, a test system is established to study the dynamic performance and energy efficiency of the speed variable power source with an auxiliary accumulator. Working performance and energy consumption of the power source under different rotating speeds and different loads are studied. And then, the hydraulic excavator test rig with the proposed system is constructed. Furthermore, the working performance of the excavator with the speed-fixed and speed-variable strategy are studied comparatively. Results show that, compared with fixed-speed strategy, the electric power consumption during the idle period and partial load condition can be reduced about 2.05 kW and 1.37 kW. The energy efficiency of speed variable power source is about 40%‒71%, which is higher than that of the fixed-speed power source by 3%–10%.

Delo temelji na zasnovi koncepta hidravličnega pogona vrat. Težo zapiralne ploskve se izravnava s primerno pred-polnjenim hidravličnim akumulatorjem. Pripravljen je matematični model preračuna hidravličnega akumulatorja kot komponente hidravličnega koncepta pogona spiralnih vrat za izravnavo teže zapiralne ploskve. Na podlagi rezultatov matematičnega modela so določeni nastavitveni parametri sistema. Poznavanje slednjih in razumevanje vpliva na dimenzioniranje hidravličnega akumulatorja, kot podsestava za izravnavo teže zapiralne ploskve, je ključnega pomena za optimalno delovanje vrat s hidravličnim konceptom pogona. V sklopu meritev smo preverili ustreznost matematičnega modela in ovrednotili koncept hidravličnega pogona z vidika zagotavljanja projektnih zahtev. Na podlagi rezultatov matematičnega modela in meritev so podane smernice nadaljnjega razvoja in izboljšave hidravličnega pogona spiralnih vrat. The work is based on the development of a concept for a hydraulic drive for a high-speed spiral door. The weight of the closing surface is to be balanced by an appropriately precharged hydraulic accumulator. A mathematical calculation model has been presented to properly design a hydraulic accumulator as a component to compensate the weight of the closing surface. The results of the mathematical model are used to determine the parameters for designing the system. Knowing which parameters and how they affect the design of the hydraulic accumulator as a subcomponent to compensate the weight of the closing surface is key to the optimal operation of doors driven by newly developed hydraulic system. As part of the measurements, the mathematical model is validated and the design of the hydraulic system is evaluated to ensure that the design requirements are met. Based on the results of the mathematical model and the measurements, guidelines are given for further development and improvement of the hydraulic drive of high-speed spiral doors.

This study is concerned with the application of two major kinds of optimisation algorithms on the hydraulic power take-off (HPTO) model for the wave energy converters (WECs). In general, the HPTO unit’s performance depends on the configuration of its parameters such as hydraulic cylinder size, hydraulic accumulator capacity and pre-charge pressure and hydraulic motor displacement. Conventionally, the optimal parameters of the HPTO unit need to be manually estimated by repeating setting the parameters’ values during the simulation process. However, such an estimation method can easily be exposed to human error and would subsequently result in an inaccurate selection of HPTO parameters for WECs. Therefore, an effective approach of using the non-evolutionary Non-Linear Programming by Quadratic Lagrangian (NLPQL) and evolutionary Genetic Algorithm (GA) algorithms for determining the optimal HPTO parameters was explored in the present study. A simulation–optimisation of the HPTO model was performed in the MATLAB/Simulink environment. A complete WECs model was built using Simscape Fluids toolbox in MATLAB/Simulink. The actual specifications of hydraulic components from the manufacturer were used during the simulation study. The simulation results showed that the performance of optimal HPTO units optimised by NLPQL and GA approaches have significantly improved up to 96% and 97%, respectively, in regular wave conditions. The results also showed that both optimal HPTO units were capable of generating electricity up to 62% and 77%, respectively, of their rated capacity in irregular wave circumstances.

This work aims to design a hydraulic hybrid vehicle model with a series transmission architecture. The hydraulic hybrid transmission uses hydro-pneumatic accumulators to store energy instead of batteries or capacitors and, although less well known, can offer several advantages compared to hybrid-electric systems. In the implemented model, a pump is connected to an engine and supplies hydraulic power to a hydraulic motor, linked to the vehicle wheels axle. Regenerative braking is enabled with the hydraulic motor, working as a pump, and returning fluid power to the accumulator. Optimization tools were used to select the dimensions of the components and to determine the values of the control variables for activating the pump/accumulator. The model implemented had its consumption reduced by about 50 \(\%\) in relation to the reference values, and the accumulator volume was reduced about 11 \(\%\) concerning the calculated analytical values.

The improved hydraulic energy storage system (IHESS) is a novel compact hydraulic ESS with only 10% of oil and 64.78% of installation space of the regular ones. However, its novel circulating structure and lightweight material result in poor heat dissipation. The thermodynamic and heat transfer model of IHESS with an oil-circulating layout is proposed. Based on the mining trucks’ dynamic model, thermal characteristics of IHESSs with different parameters under the actual and simplified working conditions are studied and the factors causing overheating are analyzed. Finally, a feasible thermal design is put forward, and its efficiency is analyzed. The simulation shows that more accumulators and higher recovery power lead to higher system temperature and vice versa. Under the standard simplified working condition at 40°C ambient temperature, the highest oil temperature reached is 93.13°C. About 90% of the generated heat is converted into the internal energy of nitrogen and oil. On this basis, by adopting an energy-saving passive cooling system with a cooling power of 6.68 kW, the highest temperature of the oil drops to 52.79°C and 28% of the generated heat is released through the cooling system.

Activities described in this paper concern the development of a newly urban transport solution which involves the revamping of electric bus and related fast-charge pantograph infrastructure. The sizing of the vehicle storage system in based on recorder mission profile and consumption acquired during real word testing, both in the real application scenarios and simulation environments. Optimal design relay on 5 Degree of Freedom vehicle model, for the purpose of estimating average consumption. These in formations are also useful to establish the size for the power and energy of the recharge infrastructures, which is equipped with flywheel inertial accumulators. Results show the accuracy of the developed model by comparing real and estimated energy consumption for several drive cycles, also concerning the effective route for the investigate bus line in the urban transport context.