0000000000047032
AUTHOR
Antonino Nucara
Automatic Computation of Local Comfort Conditions in Buildings
Publisher Summary A method for the automatic calculation of local comfort conditions in moderate indoor environment is been described in this chapter. It provides, among its output features, graphical maps of the PMV patterns. The program has been implemented on the commonly used operating system, and is characterized by a friendly usability, even by noncomputer expert users. The output of the code can be obtained not only in a graphical way but also in numerical formats. By using the program in conjunction with computer codes that provide the energy demand for climatization of buildings, it would be possible to evaluate the energy savings achieved in correspondence with the various adopted…
Implementing the sustainable energy (and climate) action plans: quasi-steady state or dynamic building modeling approach?
Actions contemplated in Sustainable Energy (and Climate) Action Plans (SEAPs), which municipalities adhering to the EU initiative called “The Covenant of Mayors” are required to prepare, regard many sectors, among which are buildings. To implement such plans, it is necessary to make use of methods for predicting energy use in buildings. Technicians involved in this tend to adopt easy-touse simulation models because of the common mid-level expertise of the offices involved. However, such simplified methods could result in a less accurate evaluation of the energy demand of buildings. In this paper the suitability of the quasi-steady state and the dynamic approach, in the frame of these new ur…
Retrofitting existing buildings by means of innovative envelope components: low-impacting new assemblies
Current policies addressing the energy efficiency of buildings aimed at the control of their overall primary energy demand, require not only that the edifice envelope has to be properly designed to optimize its thermal performances, but also that the eco-friendly properties of the involved building materials have to be properly taken into account, in order of assessing all the associated environmental costs. In fact, the design of envelope structures that are able to realize proper levels of thermal insulation and, in the same time, to employ materials characterized by low environmental impacts, are believed as the most effective strategies to be adopted in the aim of addressing the above-m…
Evaluating human body area factors from digital images: A measurement tool for a better evaluation of the ergonomics of working places
The evaluation of comfort conditions of people in confined environments requires a knowledge of the human body's radiation data. This is essentially represented by the projected area of the body in a given direction. From this factor, other important parameters can be computed, such as projected area factors and angle factors. Presently, these parameters are evaluated using graphs deriving from a pioneering field study carried out by P.O. Fanger for which a piece of apparatus using mirrors and weight operations on film negatives is used. Obviously, these graphs, apart from referring to a limited number of subjects, also involve some reading errors. With the aim of enlarging the number of ex…
An Anthropometric Analysis of Seated and Standing People
Thermal radiative exchanges of the human body with surrounding surfaces play an essential role in describing the thermal conditions of people in a given environment. Moreover, they could be induced by, among other causes, the presence of high intensity radiant sources, like lighting spots or infrared heating panels. This implies that a suitable set of radiation data related to human body anthropometry is required. This set of data mainly comprises the body surface area, the clothing area factor, the effective radiation area factor, and projected area factors. Several analytical or experimental methods may be utilized in order to compute these parameters. A detailed description of the most c…
Effect of the thermal storage dimensions on the performances of solar photovoltaic-thermal systems
Abstract PV/T panels are innovative systems increasingly used in the building sector. As a matter of fact, in that context they allow a set of common problems to be addressed and often solved: lack of physical space and economic issues, always existing when PV and thermal panels are to be installed separately. Obviously, the main objective of PV/T panels is to enhance the electrical efficiency by cooling the PV cells, but the side positive effect is also the production of thermal energy, which can be suitably exploited with a proper configuration of the whole system and an appropriate design of its components. Their energy production and overall efficiency depend on several factors and ther…
Insulating Building Components Made from a Mixture of Waste and Vegetal Materials: Thermal Characterization of Nine New Products
Nowadays, energy efficiency and sustainability are the fulcra of building policies. These policies promote the use of new technologies and materials that can reduce the primary energy involved and the environmental costs of construction, guarantying at the same time a high level of comfort for the building’s occupants. Synergy between previous construction techniques and the use of new materials should be pursued by employing materials with a low environmental impact and optimal thermal insulation properties. Within this framework, new materials derived from the agriculture sector, and waste or recycling products from the industrial/agricultural sectors have been studied. The aim of this pa…
Modelling Indoor Radiative Heath Exchanges for Effective People Thermal Comfort and HVAC Design.
Radiative heat exchanges inside buildings are responsible of a relevant part of the thermal balance of people occupying such confined spaces and, in turn, of their thermal comfort sensations. Mean radiant temperature of the internal surfaces is supposed to affect considerably this balance but, usually, it is computed by means of too simplified relationships that significantly affect the comfort evaluations. These simplified approaches can be also accountable of a less effective design of HVAC systems. Unfortunately, an accurate evaluation of the mean radiant temperature, especially when high intensity sources are present in a given internal space, depends on the angle factors between human …
Pursuing softer urban mobility behaviors through game-based apps
Cities are currently engaged through their urban policies in pushing people towards less environmentally impacting mobility modalities: therefore, cycling and walking are strongly promoted, especially by means of new and wider limited traffic and no-cars zones. In this paper, the effectiveness of the new smartphones and apps-based technologies in modifying the mobility behaviors of citizens towards more sustainable choices has been investigated. Specifically, the potential of a smartphone app, directly involving citizens by means of a game rewarding the most sustainable trips, has been tested on a university commuters' group. These latter, starting from their current mobility situation, wer…
The role of transportation and its involved sources of energy in the environmental assessment of marble producing sites
Marble is acquiring large popularity as building material. Since building materials are now required to be characterized by high energy and environmental performances, marble is entailed to fulfill top-level requirements. About its environmental performances an important European Decision establishes criteria for the award of the Community eco-label to this material. Unfortunately, this Decision is focused on mining and processing activities, seemingly neglecting marble transport. In contrast, this phase affects the whole working chain because it releases (pollutant) emissions and involves the use of primary and, in case, secondary energy sources. Here, the focus is on the role played by tr…
Outdoor Mean Radiant Temperature Estimation: Is the Black-Globe Thermometer Method a Feasible Course of Action?
Urban planning has become one of the crucial action in order to address and mitigate the effect and the consequences of the global warming and it also entails different sectors of the urban context. The survey and control of the outdoor climatic conditions are among the involved sectors and mean radiant temperature is amid the most analyzed parameters. The aim of the paper is to investigate the effective suitability of one of the most used method in the assessment of the mean radiant temperature, namely the globe-thermometer method, in outdoor urban environment, singling out possible shortcomings and actual efficacy. Specifically, data obtained by measurement campaigns performed by means of…
A model for managing and evaluating solar radiation for indoor thermal comfort
Thermal comfort of people occupying indoor spaces depends, to a large extent, on the direct component of solar radiation incident on the human body. In turn, even the diffuse component of the solar radiation could affect the thermal sensations of people. Despite this evidence, at the present there is a lack in the availability of simple and reliable methods capable of taking into account the influence of the solar radiation on thermal balance in the human body. In this work a comprehensive method is presented for the computation of the mean radiant temperature of people in thermal moderate indoor environments in the presence of solar radiation. The effects produced on the amount of solar ra…
An MAS-based subjective model for indoor adaptive thermal comfort
The achievement of high level personalized sets of comfort parameters is contemplated within the more general context of the so-called smart buildings, where people, by means of the new communication technologies, become active actors to the process of the singling out and control of the best indoor conditions. This Dynamic Intelligence approach would usefully contribute to a better energy efficient and environmental friendly management of buildings. Multi-Agent schemes are suitable tools in this aim, since they are able to manage the user-building-plant system where the adaptivity of people to the indoor conditions is suitably achieved. In this paper a contribution to a development of the …
Passive components for reducing environmental impacts of buildings:analysis of an experimental green roof
The reduction of the environmental impacts related to the building sector is a matter of outmost importance concerning the sustainable utilization of resources related to human activities. Such sector is in fact responsible for about 40% of both release of pollutants in the atmosphere and energy consumption. When trying to reduce buildings’ environmental impacts, as well as to limit their energy consumption, building envelope passive systems can be used. Amongst these, green roofs have been gaining global attention due to their benefits in terms of resilience and sustainability, in order to mitigate the unfavourable urbanization effects. Research on the green roof has been indeed increasing…
Two operative risk indicators as tools for negotiating contracts between curators of Museums and HVAC technical services providers
Abstract The purpose of Heating, Ventilating and Air-Conditioning (HVAC) systems in museums is to properly control important microclimate parameters; such systems, in fact, apart from ensuring the visitors’ wellbeing, are requested to guarantee suitable indoor conditions for the proper conservation of the important cultural goods hosted by museums. Hence, in case of disservice, or interruption due to maintenance interventions, it is important to quantify the economic damage induced to exhibited and/or stored works of art (or even to the building museum itself). Accordingly, it is essential to guarantee the shortest possible period of disservice during which probable damages for the works of…
The spatial evaluation of the radiative human body heat exchanges: An effective contribution for limiting energy consumption and achieving better indoor conditions in buildings
Abstract Radiative heat exchanges inside buildings remarkably affect the thermal balance of the human body in confined spaces and the related thermal comfort sensations of people. The mean radiant temperature is an important component of this balance. Unfortunately, it is usually computed by means of too simplified relationships, which significantly influence the comfort evaluations. Such simplified approaches are also accountable for a less effective design of HVAC systems which, in turn, could result in high energy consumption in the climatization of buildings. However, an accurate evaluation of the mean radiant temperature, especially when high intensity sources are present in a given in…
The calculation of the mean radiant temperature of a subject exposed to the solar radiation – A generalised algorithm
Abstract The thermal sensation experienced by a subject in a confined environment is significantly affected by the radiative heat exchange between the human body and the surrounding surfaces: it contributes as far as 30% of the whole thermal exchanges of the subject. Besides, the presence of high-intensity radiation sources like, for example, the sun, may appreciably modify the radiant field to which people are exposed. As a consequence, this could alter notably the comfort conditions. In order of properly taking into account this issue, a simple analytical method is introduced in this work, that allows the easy evaluation of the thermal radiant field induced by the presence of the solar ra…
Angle Factors and Projected Area Factors for Comfort Analysis of Subjects in Complex Confined Enclosures: Analytical Relations and Experimental Results
This paper addresses an important problem in the evaluation of the thermal comfort of people living or working in the sort of confined spaces typical of current architecture. In the details, a new algorithm is proposed for the evaluation of the angle factors of people within rooms characterized by complex shapes, where the envelope components are not always mutually orthogonal. The algorithm is based on field data obtained by means of an experimental photographic apparatus which allows measurements of projected area factors of seated or standing people in such complex confined environments.
Assessment of the mean radiant temperature in urban areas: methods at comparison
Mean radiant temperature may play a pivotal role in the assessment of the outdoor environmental conditions in urban areas. However, its assessment in urban settings is not a simple task owing to the presence of complex and articulated environment and of solar radiation. The article aims to perform a comparison among the results yielded by different methods: the globe-thermometer method, and the six-directional technique. The scope of such a survey is an analysis of the actual appropriateness of the more practical, albeit less accurate, globe-thermometer method to outdoor environments. Furthermore, an analytical model, previously elaborated by the authors and here modified to make it applica…
A generalized model of human body radiative heat exchanges for optimal design of indoor thermal comfort conditions
Abstract Human thermal sensation depends heavily on radiative exchanges between the human body and the surrounding environment. Because these exchanges play a crucial role in the thermal balance of the human body, about 35% of the process, human thermal sensation should draw the attention of planners when designing both indoor environments and equipment. The present study aims to contribute to this field by proposing a procedure for delineating the optimal comfort conditions for occupants in most of the articulate and realistic configurations of actual indoor environments. Specifically, this procedure enables accurate assessment of the radiant field surrounding a subject in a given indoor r…