Test bench for fatigue failure investigation by combination of acoustic emission, surface strain mapping and tensometry

Based on industrial servohydraulic testing machine the authors have designed a laboratory setup for studying behavior of structural material samples under cyclic testing. It includes in situ strain gauging data registration, surface strain mapping and acoustic emission data. Taking into account cyclic pattern of loading application the algorithms for information acquisition were offered that provides synchronization of surface image capturing with loading as well as detecting acoustic emission signals from input data flow. The operation principle of the setup is underlined by detecting and joint analysis of characteristic stages of informative parameters changing: shear strain intensity, acoustic emission activity and specimen elongation as a function of number of loading cycles. The authors tested the setup designed under tension of A7075 alloy specimens. It is shown that changing of all three informative parameters (registered by three different sensors) in time is characterized by 3 pronounced stages. The beginning of the III stage (crack propagation) coincides well for all three dependences. Difference in time of the II stage beginning is most probably related to a couple of reason. For surface strain mapping it is governed by low resolution of optical system that does not allow revealing deformation development at low spatial scales. For acoustic emission method it is associated with sensitivity of the technique to deformation mechanisms of microscale level as well as high deformation intensity at the onset of cyclic loading. If this takes place finite sensitivity of AE equipment did not allow registering all informative acoustic emission signals. The development of the offered technique and the setup is related to use of several AE sensors for solving the problems of AE source location and identification. The optical sensors of higher resolution will be attracted as well in order to increase sensitivity of stain measurement by optical technique

Perspective microwave methods of oil spill response

The detailed survey of works devoted to the processing of the crude oil containing a water oil emulsion is carried out. Results of this analysis lead to a conclusion that there are promising perspectives of using of the microwave processing technology at work on oil spill response. The technique and results of calculation of key parameters of a microwave unit of liquidation of emergency floods of oil are presented

Technical and economic model of an autonomous complex for production of «green» hydrogen and its testing on the example of Mongolia and Japan

Актуальность. Представлена технико-экономическая модель комплекса по производству сжиженного водорода с энергоснабжением исключительно от возобновляемых источников энергии. Модель позволяет проводить сравнение технико-экономических показателей производства «зелёного» сжиженного водорода в различных локациях, учитывая их природно-климатические и технико-экономические условия. Особенностью предлагаемой модели является рассмотрение основных технологических процессов производства, преобразования и хранения водорода с учетом годового почасового профиля возможной генерации энергии возобновляемыми источниками и графика отгрузки сжиженного водорода в качестве товарной продукции. Использование модели актуально на стадии предпроектных исследований по созданию водородных производств в регионах, имеющих высокий потенциал ВИЭ, но при этом удаленных от электроэнергетической инфраструктуры; позволит повысить обоснованность оценок для принятия инвестиционных решений. Цель: разработать технико-экономическую модель такого комплекса и осуществить проверку её работоспособности на примере оценки нормированной стоимости производства «зелёного» сжиженного водорода для выбранных локаций в Монголии и Японии. Объекты: автономный комплекс по производству «зелёного» водорода. Методы. Основу модели составляет оптимизационная задача математического программирования, решение которой позволяет определить уровень и структуру затрат на производство сжиженного водорода с использованием солнечной и ветровой энергии. Результаты. Для проверки работоспособности модели были получены сравнительные оценки нормированной стоимости производства товарной продукции - 10 тыс. т/год сжиженного «зелёного» водорода для локаций в Монголии (восточное побережье оз. Хубсугул) и Японии (прибрежные районы префектуры Ямагата), составляющие соответственно 10,8 и 13,4 $/кг.The relevance. The paper presents a technical and economic model of a liquefied hydrogen production complex supplied only by renewable energy. The model compares technical and economic indicators of «green» liquefied hydrogen production in different locations subject to their climate, technical and economic conditions. The unique characteristic of the proposed model is that it considers the main technological processes for hydrogen production, conversion and storage, taking into account the annual hourly profile of possible renewable energy generation and shipping schedule of liquefied hydrogen as a commercial output. Employing the model will be relevant at the stage of pre-feasibility studies devoted to the creation of hydrogen energy productions in regions with high renewable energy potentials and remote from power infrastructure and allow enhancing reasonableness of estimations when taking investment decisions. The main aim: to develop a technical and economic model of such a complex and to test it by estimating the levelized cost of «green» liquid hydrogen for selected locations in Mongolia and Japan. Object: the autonomous complex for production of «green» hydrogen. Methods. The model is based on an optimization problem that determines the level and structure of costs born to produce liquefied hydrogen using solar and wind energy. Results. For verification of the model the comparative estimations for production of 10000 tonnes per year of the liquefied «green» hydrogen were calculated. The costs for locations in Mongolia (east coast of Lake Hubsugul) and Japan (coastal areas of Yamagata Prefecture) amount to$10,8 per kg and $13,4 per kg, respectively