• Energy Research
• civil engineering close
• 7. Clean energy close
• English close

The paper is structured in seven parts, the last for few conclusions and finally some references. It is based on concrete measurements and observation during around 2 years. First is presented an introduction of the actual situation. In part two are mentioned the methods and hypotheses in evaluation of wind velocity distribution in boundary layers for atmospheric air, taking into account the roughness of ground surfaces. It is mentioned a concrete area, south part of Moldova. In third part is presented a solution for the geodetic model and finally are selected the altimetry solution. In chapter four is determined the influence of air density, temperature and pressure on wind turbine functioning. In the next chapters are presented the numerical model with special boundary conditions, taking into account different value of roughness and finally the obtained results. It is also estimated velocity variation during day-night. Finally is presented the vertical distribution of horizontal wind velocity for a wind farm, obviously important due the power of turbine (around 3 MW each one). Some conclusions and references are also mentioned.

Today, an increase of the energy efficiency in the industry is typically achieved by separate, parallel measures, primarily on the level of the individual machines. Energy efficiency can be improved by a holistic, integrated approach, which links the machines, the production process, the technical infrastructure and the building and its envelope. The subject of this paper is the development of a new prefabricated element for fa��ades and roofs, which was developed and built in the context of a research project called eta-Fabrik (i.e. energy-efficient factory, www.eta-fabrik.de) at TU Darmstadt, Germany. The element consists of purely mineral materials (concrete) and can be energetically activated by capillary tubes integrated in the surface layer. This surface layer consists of a micro-reinforced, ultra-high-performance concrete (mrUHPC) to achieve a low component thickness due to its high mechanical capacity, resistance against thermal changes, surface quality and low permeability. The core of the element is responsible for insulation. For this, a mineralized protein foam (MF) is used. It provides very good thermal insulation properties due to its eminently low density allowing low heat transfer coefficients. The final fa��ade element thus combines limiting, bearing, insulating and thermal activation using concrete. Journal of Facade Design and Engineering, Vol. 3 No. 3-4 (2015): Facade Design and Engineering

For the use in structural glazing (SSG) applications a new generation of warm edge system has been developed. This new technology is a spacer system based on polyisobutylene, especially designed for silicone sealed units, which replaces the conventional edge seal components: metal or plastic spacer, desiccant and primary sealant. In contrast to these components, this hot applied spacer system is an integrated polymer matrix incorporating the desiccant, which meets the high requirements regarding long term stability and in particular the demands for noble gas tightness of insulating glass units (IGUs) with silicone secondary sealant. In contrast to rigid spacer frames, this new spacer generation utilizes the whole inner gap size of the IGU to absorb movements caused by environmental stresses and allows full flexibility in shape of IGU. Excellent durability of the edge seal is insured by a chemical bond of the spacer matrix to glass and silicone secondary sealants. Due to the computer controlled application and the low permeability of the spacer the IGUs fulfil the requirements of the EN 1279-3 (gas tightness) even under standard mass production process conditions. This allows for an especially easy production even of triple IGUs, large formats and free shape designs with outstanding accuracy. The innovative reactive thermoplastic spacer is a new milestone in IGU technology with excellent durable energy efficiency for façades and contributes a significant step towards energy sustainability in building envelopes. Challenging Glass Conference Proceedings, Vol. 5 (2016): Challenging Glass 5

In Eastern Europe countries, including Ukraine, a significant part of the buildings belongs to the mass development of the 80s, which are characterized by a low level of energy efficiency. For such countries with sharply continental climates, heating costs prevail to a large extent. Improved thermal protection forces more attention to be paid to heat losses with ventilation. The distribution of air exchange between individual rooms is difficult to determine, especially due to natural ventilation. The work is devoted to considering the conditions of natural convection and determining the effect on the energy consumption of a building. The article considers the advanced ASHRAE technique for calculating natural air exchange. The influence of the temperature and wind characteristics of the outdoor air on the natural component of the air exchange rate at the different locations of the representative rooms of an 8-story building is analyzed. The value of the air exchange rate for typical conditions of Kiev does not exceed 0.25 h-1, 0.65 h-1 and 0.4 h-1 for two-chamber and single-chamber double-glazed windows, triple glazing in wooden double binders, respectively. On the first floors, air exchange is associated with air infiltration, and on the last floors there is exfiltration, which must be taken into account when dynamically modeling the energy characteristics of a building. The example is with additional mechanical ventilation to maintain a comfortable environment. 5R1C dynamic grid models were created to study the energy performance of the building. The estimate of additional heating costs due to infiltration is 23 % for the North and 43 % for the South orientation of rooms with two-chamber energy-saving windows. It has been established that in dynamics, the energy consumption of a building with normative air exchange and the calculated value of the natural component differs by 50–75 %, which is a possible level of savings under actual air exchange conditions in comparison with standard ones. This savings can be reduced by increasing air exchange during busy hours, for example, due to additional aeration. В странах Восточной Европы, в том числе Украине, значительная часть зданий относится к массовой застройке 80-х годов, для которых характерен низкий уровень энергоэффективности. Для таких стран с резко континентальным климатом в значительной степени превалируют расходы на отопление. Улучшение тепловой защиты заставляет больше внимания уделять тепловым потерям с вентиляцией. Распределение воздухообмена между отдельными помещениями достаточно трудно определить, особенно за счет естественной вентиляции. Работа посвящена рассмотрению условий естественной конвекции и определению влияния на энергопотребление здания. В статье рассмотрена усовершенствованная методика ASHRAE для расчета естественного воздухообмена. Проанализировано влияние температуры и ветровых характеристик наружного воздуха на естественную составляющую кратности воздухообмена при различном расположении репрезентативных помещений 8-ми этажного здания. Значение кратности воздухообмена для типичных условий Киева не превышает 0.25 ч-1, 0.65 ч-1 и 0.4 ч-1 для двухкамерный и однокамерных стеклопакетов, тройного остекления в деревянных спаренных переплетах, соответственно. На первых этажах воздухообмен связан с инфильтрацией воздуха, а на последних - присутствует эксфильтрация, что нужно учитывать при динамическом моделировании энергетических характеристик здания. Например, при дополнительной механической вентиляции для поддержания комфортных условий. Созданы динамические сеточные модели 5R1C для исследования энергетического состояния здания. Оценка дополнительных расходов на отопление за счет инфильтрации составляет 23% для северной и 43% для южной ориентации помещений с двухкамерными энергосберегающими окнами. Установлено, что в динамике энергопотребление здания при нормативном воздухообмене и рассчитанном значении природной составляющей отличается на 50-75%, что является возможным уровнем экономии при фактических условиях воздухообмена в сравнение с нормативными. Эта экономия может уменьшиться за счет увеличения воздухообмена в часы занятости, например, за счет проветривания.

The author presents a two-stage heat pump system that has a combined heat source capable of improving the system performance at approximately the same cost of consumed electricity. The author argues that the system is capable of replacing a conventional system of heat supply by thermal power plants or decentralized boiler stationsThe system can operate in the monovalent mode to cover the heating needs of the whole building. The system generates no hazardous waste; therefore, it does not pollute the environment. It also reduces the cost of heating, ventilation and hot water supply.Представлена двухступенчатая система тепловых насосов с комбинированным источником теплоты, способная повысить производительность системы при сравнительно одинаковых затратах электроэнергии

The scientific community is devoting more attention to the wide scope of offshore wind turbine structures. Since such structures are subjected to high level of fatigue loads as well as a large number of load cycles caused by wind, waves and turbine operation, the fatigue performance of welded connections is usually a design driving criteria. In this paper, a brief review on experimental fatigue analysis of circular hollow section joints for jacket structures is presented. Special emphasis is given to full-scale experimental testing. In order to face some of the challenges in this area of expertise, an experimental research plan within the framework of the Innovative Training Network (ITN) AEOLUS4FUTURE is introduced, aiming to understand and validate the fatigue performance of circular hollow section joints produced by an automated process, using Tandem MIG/MAG welding.

{"references": ["A. Babarit, J. Hals, M.J. Muliawan(2012). Numerical benchmarking study of a selection of wave energy converters. Renewable Energy, 6(7), 131~142.", "Meyer NI, McDonalArnskov M, VadBennetzen CE, etc(2002). B\u00f8lgekraftprogram, Afslutningsrapport, Virum, Denmark RAMB\u00d8LL, Teknikerbyen 31, 2830.", "Previsic M, Bedard R, Hagerman G(2002). E2I EPRI assessment, offshore wave energy conversion devices. Electricity Innovation Institute;Technical report E2I EPRI WP - 004 - US - Rev 1.", "Manases(2010). Dynamics and hydrodynamics for floating wave energy converters. Ph.D. thesis, Lisboa University, Lisboa.52~59", "Nicolai F. HEILSKOV and Jacob V(2012). A non-linear numerical test bed for floating wave energy converters. Book of extended abstracts for the 2ndSDWED Symposium, Copenhagen 524-532.", "Newman J N(1994). Wave effects on deformable bodies .Applied Ocean Research, 16: 47~59.", "Gou Ying, TengBin(2004). Interaction effects between wave and two connected floating bodies. Engineering Science, 6(7), 75~80.", "L. Sun, R. Eatock Taylor and Y.S. Choo (2011). Responses of interconnected floating bodies. The IES Journal Part A: Civil & Structural Engineering, 4(3), 143\u2013156", "Chuankun Wang,Wei Lu (2009) Analysis on ocean energy resources and storage, Ocean press, Beijing, China, 110-116\n[10]\tQin Ye, Zhongliang Yang, Weiyong Shi(2012), The preliminary research on the offshore wave energy resources in Zhejiang province, Journal of Marine Sciences, 30(4) 13-19\n[11]\tJ.N.Newman (1986). Marine Hydrodynamic. Massachusetts Institute of Technology Press, Massachusetts, America, 40-45\n[12]\tYishan Dai, WenyangDuan(2008). Potential Flow Theory of Ship Motions in Waves. National Defence Industry Press, Beijing, China,80-86\n[13]\tZhengban Sheng, YingzhongLiu(2003). Ship manoeuvringandseakeeping, Shanghai Jiao Tong University Press, Shanghai, China, 283-210.\n[14]\tPizer, D.J, Retzler, C.H.Yemm, R.W(2000). The OPD pelamis. Experimental and numerical results from the hydrodynamic work program. European wave energy conference, Aalborg (Denmark), 227-234."]} Based on three dimensional potential flow theory and hinged rigid body motion equations, structure RAOs of Pelamis wave energy converter is analyzed. Analysis of numerical simulation is carried out on Pelamis in the irregular wave conditions, and the motion response of structures and total generated power is obtained. The paper analyzes influencing factors on the average power including diameter of floating body, section form of floating body, draft, hinged stiffness and damping. The optimum parameters are achieved in Zhejiang Province. Compared with the results of the pelamis experiment made by Glasgow University, the method applied in this paper is feasible.

With wind power establishing itself as a widely effective form of renewable energy source, a diverse range of maintenance schemes is being investigated towards life-time extension of existing wind farms. Among the numerous structural and mechanical parts of a Wind Turbine (WT), blades are the most critical and costly components. Exposed to a number of degradation mechanisms, such as cracks and fatigue, they may be well rendered structurally ineffective and unsafe. Detecting and localizing thus the existence of damage on WT blades is a crucial and essential task for planning optimal maintenance and assuring operational reliability of WTs. One of the main challenges for deploying Structural Health Monitoring (SHM) methodologies on in-service WT blades lies in the operational and environmental variability. It is widely reported that fluctuations in ambient temperature exert a strong impact on the vibration features of WTs, insinuating the damage induced structural changes may often be masked by changes due to temperature influences. With WTs operating in highly-varying climate conditions, it becomes thus imperative that temperature effects be properly taken into account within the context of damage detection and localisation. In this contribution, the most common vibration-based criteria for damage localization are examined and compared through a numerical application on a small- scale WT blade. The study is built around a 3-dimensional finite element model of the blade, which comprises an exterior laminate composite surface, modelled with shell elements, and interior foam represented by solid elements. The efficacy of localization is evaluated under varying environmental conditions and a critical assessment on the accessibility of sensing information and the severity of damage is presented. 9th European Workshop on Structural Health Monitoring (EWSHM 2018): Online Proceedings

{"references": ["Zhang, Z., Wu, X., Yang, X., Zhu, Y., BEPAS - A life cycle building\nenvironmental performance assessment model, Building and\nEnvironmental 51(5) (2006), pp. 669-675", "Radhi, H., On the optimal selection of wall cladding system to reduce\ndirect and indirect CO2 emissions, Energy 35(3) (2010), pp. 1412-1424", "Gartner, E., Industrially interesting approaches to \" low-CO2\" cements,\nCement and Concrete Research 34(9) (2004), pp. 1489-1498", "Wang, W., Zmeureanu, R., Rivard, H., Applying multi-objective genetic\nalgorithms in green building design optimization, Building and\nEnvironment 40(11) (2005), pp. 1512-1525", "Sartori, I., Hestnes, A.G., Energy use in the life cycle of conventional and\nlow-energy buildings: A review article, Energy and Buildings 39(3)\n(2007), pp. 249-257", "Ki-Bong Park, Takafumi Noguchi, Environmental Concern Concrete and\nReinforced Concrete Construction for Low Carbon Green Growth, Korea\nConcrete Institute 21(4) (2009), pp.44-49", "Guggemos, A.A., Horvath, A., Comparison of Environmental Effects of\nSteel- and Concrete-Framed Buildings, Journal of Infrastructure Systems\n11(2) (2005), pp. 93-101", "Cole, R.J., Energy and greenhouse gas emissions associated with the\nconstruction of alternative structural systems, Building and Environment\n34(3) (1998), pp. 335-348", "Moon, K.S., Sustainable structural engineering strategies for tall building,\nThe Structural Design of Tall and Special Buildings 17(5) (2008), pp.\n895-914\n[10] Paya-Zaforteza, I., Yepes, V., Hopitaler, A., Gonzalez-Vidosa, F.,\nCO2-optimization of reinforced concrete frames by simulated annealing,\nEngineering Structures 31(7) (2009), pp. 1501-1508\n[11] Paya, I., Yepes, V., Gonzalez-Vidosa, F., Hospitaler, A., Multiobjective\noptimization of concrete building frames by simulated annealing,\nComputer-Aided Civil and Infrastructure Engineering 23(8) (2008), pp.\n596-610\n[12] Saw, H.S. and Liew, J.Y.R., Assessment of current methods for the design\nof composite columns in buildings, Journal of Constructional Steel\nResearch 53(2) (2000), pp. 121-147\n[13] Holland, J.H., Adaptation in natural and artificial system, Univ. Michigan\nAnn Arbor, MIT. (1975)\n[14] C. Lee and J. Ahn, Flexural Design of Reinforced Concrete Frames by\nGenetic Algorithm, Journal of Structural Engineering 129(6) (2003), pp.\n762-774"]} Environmental pollution problems have been globally main concern in all fields including economy, society and culture into the 21st century. Beginning with the Kyoto Protocol, the reduction on the emissions of greenhouse gas such as CO2 and SOX has been a principal challenge of our day. As most buildings unlike durable goods in other industries have a characteristic and long life cycle, they consume energy in quantity and emit much CO2. Thus, for green building construction, more research is needed to reduce the CO2 emissions at each stage in the life cycle. However, recent studies are focused on the use and maintenance phase. Also, there is a lack of research on the initial design stage, especially the structure design. Therefore, in this study, we propose an optimal design plan considering CO2 emissions and cost in composite buildings simultaneously by applying to the structural design of actual building.