1,721,247 research outputs found
The conservation project in polarity of the multidimensional survey. The need for critical discussion drafting of operating protocols. Modernity and tradition: the wooden caisson in the great hall of the Economic School in Naples
No full textThe paper focuses on the multidisciplinary study of the coffered ceiling wooden, existing in the Great Hall of the School of Economics of Naples. One of the rare examples of wooden work carried out in Italy in the twentieth century, designed by Roberto Pane, master of Italian architecture and academia.. The multidisciplinary and multidimensional approach has involved researchers and academics active in remote sensing and 3D modeling (Argenziano P.), in the conservation and restoration (Saverio Carillo, Petillo Pasquale, Luca Ferri), in lighting and colorimetry (Sibilio Sergio, Falconetti Pasquale).. The direct and instrumental survey, from 3D modeling to videoendoscopy, from the characterization of materials and coatings, the work has allowed us to understand the material composition of the coffered ceiling and its manufacturing technology in a non-invasive approach. This protocol will be useful for a possible conservation work of the coffered ceiling in question and also provides a scientific protocol for the analytical study of coffered wood of any size and timing
Energy performance of a micro-cogeneration device during transient and steady-state operation: experiments and simulations
No full text"Micro-cogeneration is a well-established technology and its deployment has been considered by the. European Community as one of the most effective measure to save primary energy and to reduce. greenhouse gas emissions.. As a consequence, the estimation of the potential impact of micro-cogeneration devices is necessary to. design policy and to energetically, ecologically and economically rank these systems among other potential. energy saving and CO2-reducing measures. Even if transient behaviour can be very important. when the engine is frequently started and stopped and allowed to cool-down in between, for the sake of. simplicity mainly static and simplified methods are used for assessing the performance of cogeneration. devices, completely neglecting the dynamic response of the units themselves.. In the first part of this paper a series of experiments is illustrated and discussed in detail in order to. highlight and compare the transient and stationary operation of a natural gas fuelled reciprocating internal. combustion engine based cogeneration unit with 6.0 kW as nominal electric output and 11.7 kW as. nominal thermal output.. The measured performance of the cogeneration device is also compared with the performance of the. system calculated on the basis of the efficiency values suggested by the manufacturer in order to. highlight and quantify the discrepancy between the two approaches in evaluating the unit operation.. Finally the experimental data are also compared with those predicted by a simulation model developed. within IEA\/ECBCS Annex 42 and experimentally calibrated by the authors in order to assess the. model reliability for studying and predicting the performance of the system under different operating. scenarios.
Calibration and validation of a model for simulating thermal and electric performance of an internal combustion engine-based micro-cogeneration device
No full text"The growing worldwide demand for more efficient and less polluting forms of energy production has led to a renewed interest in the use of micro-cogeneration technologies in the residential. Among the others technologies, internal combustion engine-based micro-cogeneration devices are a market-ready technology gaining an increasing appeal thanks to their high efficiency, fuel flexibility, low emissions, low noise and vibration.. . In order to explore and assess the feasibility of using internal combustion engine-based cogeneration systems in the residential sector, an accurate and practical simulation model that can be used to conduct sensitivity and what-if analyses is needed. A residential cogeneration device model has been developed within IEA\/ECBCS Annex 42 and implemented into a number of building simulation programs. This model is potentially able to accurately predict the thermal and electrical outputs of the residential cogeneration devices, but it relies almost entirely on empirical data because the model specification uses experimental measurements contained within a performance map to represent the device specific performance characteristics coupled with thermally massive elements to characterize the device's dynamic thermal performance.. . At the Built Environment Control Laboratory of Seconda Università degli studi di Napoli, an AISIN SEIKI micro-cogeneration device based on natural gas fuelled reciprocating internal combustion engine is available. This unit has been intensively tested in order to calibrate and validate the Annex 42 model. This paper shows in detail the series of experiments conducted for the calibration activity and examines the validity of this model by contrasting simulation predictions to measurements derived by operating the system in electric load following control strategy. The statistical comparison was made both for the whole database and the segregated data by system mode operation.. . The good agreement found in the predictions of net electric power production, useful thermal output and primary power consumption allowed to conclude that the Annex 42 model can be used to carry out a detailed performance assessment in order to examine the applicability of the AISIN SEIKI unit for supplying building electrical and thermal energy requirements according to different load profiles during annual or multi-year operation.
Performance assessment of a micro-cogeneration system under realistic operating conditions
No full text"The European Parliament stated that high-efficiency cogeneration is a Community priority given the. potential benefits of cogeneration with regard to saving primary energy and reducing emissions. Accord-. ing to this position, the performance of many micro-cogeneration systems have been assessed from an. energy and environmental point of view. However, in the most part of cases, the assessments have been. performed by using technical data from manufacturers and\/or experimental results measured during. steady-state operation, without considering the inefficiencies related to the transient periods; in addi-. tion, few works have been devoted to analyze the system operation from an exergy-based point of view.. In this paper the electric load-following operation of an internal combustion engine based micro-. cogeneration unit with 6.0 kW as nominal electric output has been experimentally investigated in electric. load-following operation during a 24 h dynamic test with the application of a realistic daily load profile. representing the Italian domestic non-HVAC electric demand for a multi-family house of five dwellings.. The measured data have been compared with those that would be associated with servicing the building. with electricity from the central electric grid and heat from a natural gas fired boiler from an energy,. exergy and environmental points of view,
Preliminary experimental characterization of a three-phase absorption heat pump
No full text"In this paper a recently commercialized three-phase absorption heat pump that is capable of storing energy internally in the form of crystallized salt (LiCl) with water as refrigerant. has been experimentally investigated during summer period. The tests have been performed. with the aim to investigate the operation logic of the machine and to highlight both. the reliability and the efficiency of the system over an operating conditions range of great practical interest.. The measured performance have been compared with those of a conventional electrically. driven vapor compression refrigerating system from an energy, environmental and. economic point of view in order to assess the suitability of the absorption heat pump: this comparison showed that the absorption system is potentially able to guarantee an energy saving, a reduction of carbon dioxide emissions and a lower operating cost only in case of the most part (at least 70%) of required thermal energy is supplied by solar collectors.
Misure e simulazioni illuminotecniche e termo igrometriche per la fruibilità dei beni architettonici, in Materia Cimitile. Memoria di segno. Misura di storia
No full textYearly operation of a building-integrated microcogeneration system in south Italy: energy and economic analyses
No full textThis article investigates the yearly operation of a building-integrated micro-cogeneration system through transient simulations; both energy and economic performance of the proposed system are analyzed and compared with those of a conventional system based on separate energy production in order to assess the potential savings. The energy comparison is carried out in terms of primary energy with respect to the specific Italian electricity mix; the economic analysis is performed by considering both the operating and capital costs, with the energy unit costs as well as the incentives for supporting the cogeneration technology evaluated according to the Italian scenario
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