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In this paper an accurate description of a combination water meter is provided. Therefore, the main results of calibration tests are presented. Final considerations about the reliability of a combination meter in very wide flow range applications are also reported.

Evaporative cooling can be adopted in wet areas by integration into HVAC systems. Processing TRY data for Italy, the economics of three-stage evaporative cooling systems were examined. Summertime conventional system operating costs and hybrid system savings were evaluated. The method was based on a simplified approach that is not intended as a substitute for accurate dynamic modelling, but as a simple analysis tool. The results were found to be strongly dependent on: climatic area, internal set point, initial cost of extra equipment. The highest savings appeared to be achieved in the middle-south of Italy. © 1999 Elsevier Science Ltd. All rights reserved.

The problem of HCFC22 phase-out in refrigeration plants is analysed. A comparison is performed between R22 and R407C. The latter seems a promising drop-in substitute. Indeed, its use in existing plants would only require discharge of mineral oil and refilling with a compatible polyolester oil. The experimental tests are performed in a plant consisting in a water-cooled vapor-compression circuit employed for cooling a water–glycol mixture in a closed-loop system. Both the thermodynamic properties and general performance of R407C are comparable with those of R22. The COP, however, is 5–17% lower. As a consequence, in order to provide the same refrigerating load, a plant working with R407C requires higher electric-power consumption. The operational behaviour of R407C is increasingly better with increasing condensation and evaporation temperature. Therefore, R407C is a good R22 substitute in all applications requiring high evaporation temperatures, such as air-conditioning plants. © 1997 John Wiley & Sons, Ltd.

In this paper a novel dynamic energy performance simulation model for the Phase Change Materials (PCM) analysis is presented. The model is implemented in a suitable computer code, written in MatLab and called DETECt, for complete building energy analyses. In the presented model, the “effective specific heat” method is implemented. Here, the specific heat of each PCM layer changes as a function of the system phase and temperature in both melting and freezing processes. A model validation is carried out by comparing numerical results vs. measurements obtained at Solar Laboratory of Concordia University (Montreal, Canada). The simulation model allows exploring the potential of PCMs to increase the thermal inertia of buildings envelopes and to assess the effects/weight of several design parameters (e.g. PCMs melting temperature, etc.) on the building heating and cooling energy demand and on the related thermal comfort. In order to show the potentiality of the presented simulation model, suitable case studies referred to residential and office buildings, to three different weather conditions and to two alternative PCM layouts in the building envelope, are developed.

In this paper, the energy performance of a façade open loop Building Integrated Photovoltaic/Thermal (BIPV/T) system with air as working thermal fluid is investigated. For this aim a new dynamic simulation model based on a detailed transient finite difference thermal network is developed. For a complete building energy performance analysis, such model was implemented in a suitable computer tool written in MatLab (called DETECt 2.3, suitably modified). The presented simulation model includes a parametric analysis tool useful to minimize the building energy demand. In order to show the potential of the developed code, a comprehensive case study related to a multi-floor office building located in several climate zones is developed. In particular, with the aim to identify the design and operating parameters minimizing the overall energy consumptions, while guaranteeing the comfort of occupants, a suitable optimization procedure is carried out. Results show that through the produced electricity and thermal energy it is possible to balance the overall building energy demand approaching the NZEB goal.

In this paper, the energy and environmental impacts of a passive retrofit action, involving the installation, on an office building, of a second-skin system with the external layer made of a PVC-coated polyester fabric, were evaluated in terms of primary energy saving and carbon dioxide equivalent emissions. The primary energy consumption and the carbon dioxide equivalent emissions associated with the considered case studies were evaluated using the software TRNSYS, across a whole year. The study was carried out considering three Iranian cities (Tabriz, Teheran and Bandar Abbas) in three different climates (cold, temperate and hot) upon varying the orientation of the two main façades of building (north-south and east-west orientation). The simulation results highlighted good results when the building is east-west oriented, up to -12.9% for the reduction of primary energy consumption (in Teheran) and up to -42.1 MgCO2,eq (in Tabriz) for the carbon dioxide equivalent emissions.

The improvement of the energetic performances of the building envelope represents a crucial aspect to increase the buildings energy efficiency and indoor environmental quality. In recent years, one of the most appreciated design solutions in the worldwide architecture panorama is the Double-Skin Façade. A lot of different technologies and innovative materials have been proposed lately to improve or modify Double-Skin Façade appearance and energy efficiency. Unfortunately, there is still a lack of numerical models able to reproduce coherently and comprehensively the behaviour of complex Double-Skin Façades, let alone the cases in which innovative materials or geometries are used. Therefore, two identical test-cells (called GEMINI) for on-site acoustic, visual and thermal characterization of different full-scale modules for Double-Skin Façades have been designed and are currently under construction at University of Campania “Luigi Vanvitelli”. In this paper, their structure, equipment and measurements layouts are presented and described in detail.

Today, strategies for emergency preparedness, in presence of accidental scenarios in high-risk plants with releases into the atmosphere, have become a priority. To achieve this goal, it is important to have forecast meteorological data in local areas to use in dispersion and transport models and so to respond in advance emergency situations. The paper reports results of research performed to develop a new tool, called FORCALM that is capable to elaborate European Centre for Medium-Range Forecasts (ECMWF) forecast data to use for simulations by CALMET/CALPUFF modeling system. A case study, relevant to an accident occurred in Mediterranean Refinery at Milazzo (Italy), has been examined to validate the procedure and the capacity to evaluate the transport and depositions pollutant in terms of forecast information. The results were compared with those obtained using CALMET/CALPUFF simulations based on measured meteorological, covering the area under study.