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[en] This document, produced at the request of the Geothermal Technical Committee, takes up an analysis of the reciprocal influences of realized and potential geothermal operations made at and near Sarcelles, north of Paris. The results of the simulation calculations show that the approach (which can be qualified as pessimistic) provides a first layout diagram that should be adjusted during the chronological drilling sequence. It is in fact not certain at all that the various production levels identified on the first borehole, of 'metric' thickness, are continuous over the entire extent of the area studied. It is therefore absolutely necessary to provide for successive revisions of the model (which may lead to corrective measures on the initial layout) as the boreholes are carried out. Up to eight borehole 'doublets' are considered over a period of 5 years
[fr]Ce document analyse les influences reciproques des exploitations geothermiques realisees et potentielles sur les communes de Garges-Les-Gonesse, Gonesse, Villiers-le-Bel et Sarcelles. Compte tenu de la connaissance actuelle des parametres du reservoir, les resultats des calculs de simulation n'appellent pas de commentaires particuliers. L'approche effectuee peut etre qualifiee de pessimiste et fournir un premier schema d'implantation qu'il conviendra d'ajuster au cours de la sequence chronologique de forage. Il n'est en effet pas certain, a priori, que les differents niveaux producteurs identifies sur le premier forage, et d'epaisseur sensiblement metrique, soient continus sur toute l'etendue du domaine etudie. Il est donc absolument necessaire de prevoir des revisions successives du modele (pouvant entrainer des correctifs sur le schema d'implantation initial) au fur et a mesure de la realisation des forages. Il semble tres optimiste d'envisager cinq doublets a Sarcelles, compte tenu de l'avis des services techniques de la ville, de la presence d'une usine d'incineration, du nombre et de la localisation des batiments a raccorder. En tout etat de cause, si cinq doublets etaient prevus a Sarcelles, la configuration proposee dans le rapport est admissible. Il est particulierement important de savoir des la realisation du 1er doublet si l'operation globale comportera trois, quatre ou cinq doublets, ainsi que leur date approximative de realisation. Le modele analyse prend en compte des doublets realises en meme temps ou presque. Il est evident qu'un planning etendu sur cinq ans ou plus entrainerait des modifications non negligeables. L'option huit doublets, beaucoup plus realiste a notre avis, permet la realisation des seize forages sans qu'un probleme majeur d'interaction ne soit previsible. L'un des problemes souleves par cette etude est la sophistication des modeles mathematiques utilises. En effet, jusqu'a present, les modelisations se font avec des parametres constants, il est par exemple impossible (ou tres long) de prendre en compte un aquifere a hauteur productrice variable, ou bien echelonner la mise en service des operations, ou de faire varier le debit reinjecte le long de la saison de chauffe, etc. L'Institut de Recherches Geothermiques est en train de mettre au point un modele mathematique qui tiendra compte des limitations des modeles actuellement utilises. Il sera certainement tres utile, des que ce programme sera operationnel, de comparer les resultats et ainsi d'affiner les previsions
[en] The design of an external wall is proposed, it allows for efficient utilization of solar energy to reduce the load on buildings heating. A special feature of the technical solution is the location of thermal insulation from the inside of the energy-active fence with air space formation relative to the accumulating layer. The given design makes it possible to avoid accommodations overcooling in case of adverse weather conditions during the cold season and overheating during warm weather. It was proposed to base costs increase for energy-saving buildings construction including those with integrated solar radiation conversion systems and to use the methodology for estimating additional technical solutions based on the calculation of economic efficiency. (paper)
[en] This paper presents the solution of highly complex, non-linear, multi-objective Dynamic Combined Economic Emission Dispatch (DCEED) problem. DCEED is a power system optimization problem with conflicting objectives of fuel cost and emission. DCEED includes constraints like valve point loading effect, Transmission Losses and Ramp Rate limits. Solution of DCEED problem is given by a novel Hybridized Flower Pollination Algorithm (FPA) with Sequential Quadratic Programming (SQP). FPA is a nature inspired population based meta-heuristic optimization technique that models its search on the flower pollination process. The non-convex nature of generation because of numerous operational, physical and dynamic constraints, makes search space highly multi model and complex. This makes DCEED a challenging as well as an attractive problem for research. The effectiveness of FPA-SQP is tested and validated by applying it on IEEE Standard 5-unit and 10 unit non-convex test system in MATLAB environment for the time interval of 24 hours. The results achieved by this algorithm show significant reduction in cost and emission as compared to other available techniques in the literature. (author)
[en] When conducting an energy survey of heat supply enterprise operating several boilers located not far from each other, it is advisable to assess the degree of heat supply efficiency from individual boiler, the possibility of energy consumption reducing in the whole enterprise by switching consumers to a more efficient source, to close in effective boilers. It is necessary to consider the temporal dynamics of perspective load connection, conditions in the market changes. To solve this problem the radius calculation of the effective heat supply from the thermal energy source can be used. The disadvantage of existing methods is the high complexity, the need to collect large amounts of source data and conduct a significant amount of computational efforts. When conducting an energy survey of heat supply enterprise operating a large number of thermal energy sources, rapid assessment of the magnitude of the effective heating radius requires. Taking into account the specifics of conduct and objectives of the energy survey method of calculation of effective heating systems radius, to use while conducting the energy audit should be based on data available heat supply organization in open access, minimize efforts, but the result should be to match the results obtained by other methods. To determine the efficiency radius of Kazan heat supply system were determined share of cost for generation and transmission of thermal energy, capital investment to connect new consumers. The result were compared with the values obtained with the previously known methods. The suggested Express-method allows to determine the effective radius of the centralized heat supply from heat sources, in conducting energy audits with the effort minimum and the required accuracy. (paper)
[en] In this review work, energy harvesting methods for waste heat with small temperature differences between heat source and sink are discussed. At present, many methods are tried and employed to utilize this type of waste heat. A typical example is found in a conventional power generation system. By utilizing this type of waste heat, additional energy can be produced in regular power generation systems. Up to this point, two energy harvesting methods have been introduced and applied for the use with this type of waste heat. One is a method using an organic Rankine cycle (ORC) while the other is a method using a thermoelectric generation (TEG). An ORC is a Rankine cycle that can be applied to this type of waste heat using organic fluids such as refrigerants as working fluids instead of water used in a typical Ranking cycle. On the other hand, a TEG utilizes Peltier, Seebeck, and Thomson effects caused by the temperature difference between the heat source and sink for energy harvesting. In this work, various aspects associated with the use ORC and TEG for waste heat harvesting with small temperature differences between the heat source and sink.
[en] Methodology for thermodynamic analysis, fuel efficiency determination, and mathematical economic calculation model of comparative economic effectiveness of combined-cycle cogeneration plant (CCCP) are elaborated. CCCP with a single, dual and triple pressure heat-recovery steam generators (HRSG) are investigated with account for real-time use in Heating System. Employment of CCCP with a triple pressure HRSG ensure high value of system effectiveness. Modes of CCCP, conditional and functional scope of electricity and heat, and condition of construction investment financing of CCCP are main factors have an impact on effectiveness of different schemes of CCCP. (paper)
[en] For the heating and cooling supply of buildings and constructions geothermal heat pumps using low-potential ground energy are applied by means of ground exchangers. The process of heat transfer in a system of ground exchangers is a phenomenon of complex heat transfer. The paper presents a mathematical modeling of heat exchange processes, the temperature fields are built which are necessary for the determination of the ground array that ensures an adequate supply of low potential energy excluding the freezing of soil around the pipes in the ground heat exchangers and guaranteeing a reliable operation of geothermal heat pumps. (paper)
[en] In the present study, shaped inorganic hydrated salt-based phase change materials (PCMs) were prepared using a high-absorbent resin (acted as the support material) and a water retaining agent. The synthesized materials were added to a prefabricated wall, and measurement points were placed on the low-temperature side of the wall. The heat transfer performance of the wall was tested by a multi-point heat flow meter. The temperature and the heat flow rate at the low-temperature side of the wall were compared with the heat transfer performances of an ordinary wall and an amorphous phase-change wall. The obtained results revealed that the wall with PCMs manifested stable heat transfer performance with good heat storage capacity; thus it caused an improvement in indoor thermal comfort and achieved a good energy-saving effect. Results of the present study demonstrate the feasibility of PCMs in wall energy storage applications. (paper)
[en] This book contains the papers presented at the 51st Power Plant Engineering Colloquium held in Dresden on October 22-23, 2019. The following topics were covered: New construction and pilot projects in power plant technology, combustion and steam generators, nuclear energy systems, energy machines, process simulation, measurement technology and digitalization, integration of renewable energy sources, grids, operation and maintenance.
[de]Das vorliegende Buch enthält die Beiträge des 51. Kraftwerkstechnischen Kolloquiums vom 22. und 23. Oktober 2019 in Dresden. Folgende Themen wurden behandelt: Neubau- und Pilotprojekte in der Kraftwerkstechnik, Verbrennung und Dampferzeuger, Kernenergetische Systeme, Energiemaschinen, Prozesssimulation, Messtechnik und Digitalisierung, Integration regenerativer Energieträger, Netze, Betrieb- und Instandhaltung.
[en] Bamboo scrimber was fiber based panel developed in 2000s that was potential to be an ideal substitute for construction timber in bamboo growing areas. For evaluating the performance of applying bamboo scrimber in building envelope by clarifying the performance difference with timber, softwood (SW) and hardwood (HW) units were set as reference model, accordingly bamboo scrimber (BFB) units of the same construction and space size as evaluation model, by which performance regarding to building component and space unit were compared. Space units enclosed with bamboo, softwood and hardwood exterior walls were constructed and simulated in WUFI Plus for 16 cities from tropical and humid subtropical regions overlapped with the bamboo forest distribution. Bamboo scrimber showed changeable strengths of heat storage and vapor resistance and weakness of heat transport properties, which varied with the external climate, building function, construction type and HVAC condition. (paper)