With the proliferation of technologies and underground systems, analysis of thermal fields in soi... more With the proliferation of technologies and underground systems, analysis of thermal fields in soil has become a topic of great interest in the developing technology of buried structures. In this work, we have investigated the steady state temperature field (from linear heat sources - buried cable -) in a different type of soil and excavation geometry. In a laboratory, a physical model was built on scale, which reproduces an "undisturbed" area containing a linear thermal source. This scale model was produced for experimental activity. A measuring chain was made to analyze the thermal field in various types of soils, by varying the electrical current through the line source. The physical model was recreated using a finite volume calculation software. Analysis of the different field system configurations were completed and we have studied a model for the improvement of the design method.
The present study wants to highlight the importance of the reliability parameters because of some... more The present study wants to highlight the importance of the reliability parameters because of some changes that occurred in modern technology; as for example the necessity of more sophisticated equipments or plants transformed from an auxiliary service to being an actual part of the systems they were originally intended for. Reliability, maintainability and availability are essential features if we want to define the quality that is the ability, of the plant to fulfill a specific requirement. Obviously analyzing the reliability is useful for those plants that must guarantee an uninterrupted service, thus making an estimation of the probability that a malfunctioning, either of component or a security system, can generate an accidental sequence generating a downtime. Even in plants which do not risk the occurrence of a considerable incident, the analysis of reliability can affect positively costs regarding both security and management. The importance of reliability parameters increases when those requirements the system must fulfill change. Anyway these systems have a safe impact on the costs of exertion and management. Such costs will be added to the ones produced by the energy consumption of the plant. By using the word costs we mean: installation and management costs; a high efficient and reliable plant usually has high installation costs and low exertion costs. The opposite situation occurs in highly maintainable plants only under specific circumstances.
Understanding if a technologic solution satisfies the energy demands of a residential neighbourho... more Understanding if a technologic solution satisfies the energy demands of a residential neighbourhood, and whether it is financially a benefit or not, cannot be determined by the only amount of energy that can be saved. Technologies such as CCHP could represent the perfect answer to this problem, on one condition though: it must be taken into consideration the reliability parameter as well. The plant configuration should guarantee a service without any interruptions. Redundancies must be evaluated and the consequences of the installation costs they imply. This study presents a method to make the right choice about an energy system characterized by: energy, reliability and economic services which satisfy power supplying to a polygeneration grid in a residential context. The case study is the area of Arci, near Rome, Italy. Our purpose is to realize a teleheating network and create a system able to satisfy the electric demands of the area. The first step is an accurate estimation of the electrical and thermal demands. Then we compare the optimized energy solutions with the traditional ones. Some changes have been introduced to improve the system's availability. All these steps take to an economic evaluation able to give some useful information about the feasibility of the technical choices previously made.
The European Union is working on strategies in order to increase the energy efficiency of buildin... more The European Union is working on strategies in order to increase the energy efficiency of buildings. A useful solution is to identify the energy performance of buildings through the Energy Performance Certificate (EPC), as it provides information for the comparison of buildings with different architectural typology, shape, design technology and geographic location. However, this tool does not assess the real energy consumption of the building and does not always take into account its impact on the environment. In this work, two different types of analysis were carried out: one based only on the energy efficiency and the other one based on the environmental impact. Those analyses were applied on a standard building, set in three different Italian locations, with the purpose of obtaining cross-related information. After the evaluation of the results, interventions on some parameters (walls insulation, windows frame, filler gas in the insulated glazing) have been identified in order to improve the energy behavior of the building with an acceptable environmental impact. The aim of this paper is to propose a methodology that integrates the EPC with green building rating systems, leading to a more conscious choice of retrofit interventions as a compromise between energy performances and environmental impact.
ABSTRACT Outdoor thermal comfort affects the health of the people and the quality of life in urba... more ABSTRACT Outdoor thermal comfort affects the health of the people and the quality of life in urban areas. This is the reason why in the past few years different mitigation strategies for the microclimate have been studied and examined. These strategies depend on those passive factors characterizing the urban setting that are able to affect the values of local meteorological variables, as the limit surfaces of the urban space (parterre and façades of the buildings). This paper examines the Cloister by Giuliano da Sangallo, which is part of the Faculty of Engineering of Sapienza University of Rome. The case study compares the present configuration of the Cloister with four other configurations characterized by some vegetation and materials with a high albedo by taking into consideration the PMV (Predicted Mean Vote) model. Microclimatic variables are calculated through numerical simulations performed by the ENVI-met software. Such a comparison is performed during a typical summer day. While examining the results it can be noticed how the strategy presenting the best results is the one with some vegetation, whereas the materials with a high albedo improve the microclimate if applied on surfaces characterized by a high sky view factor.
With the proliferation of technologies and underground systems, analysis of thermal fields in soi... more With the proliferation of technologies and underground systems, analysis of thermal fields in soil has become a topic of great interest in the developing technology of buried structures. In this work, we have investigated the steady state temperature field (from linear heat sources - buried cable -) in a different type of soil and excavation geometry. In a laboratory, a physical model was built on scale, which reproduces an "undisturbed" area containing a linear thermal source. This scale model was produced for experimental activity. A measuring chain was made to analyze the thermal field in various types of soils, by varying the electrical current through the line source. The physical model was recreated using a finite volume calculation software. Analysis of the different field system configurations were completed and we have studied a model for the improvement of the design method.
The present study wants to highlight the importance of the reliability parameters because of some... more The present study wants to highlight the importance of the reliability parameters because of some changes that occurred in modern technology; as for example the necessity of more sophisticated equipments or plants transformed from an auxiliary service to being an actual part of the systems they were originally intended for. Reliability, maintainability and availability are essential features if we want to define the quality that is the ability, of the plant to fulfill a specific requirement. Obviously analyzing the reliability is useful for those plants that must guarantee an uninterrupted service, thus making an estimation of the probability that a malfunctioning, either of component or a security system, can generate an accidental sequence generating a downtime. Even in plants which do not risk the occurrence of a considerable incident, the analysis of reliability can affect positively costs regarding both security and management. The importance of reliability parameters increases when those requirements the system must fulfill change. Anyway these systems have a safe impact on the costs of exertion and management. Such costs will be added to the ones produced by the energy consumption of the plant. By using the word costs we mean: installation and management costs; a high efficient and reliable plant usually has high installation costs and low exertion costs. The opposite situation occurs in highly maintainable plants only under specific circumstances.
Understanding if a technologic solution satisfies the energy demands of a residential neighbourho... more Understanding if a technologic solution satisfies the energy demands of a residential neighbourhood, and whether it is financially a benefit or not, cannot be determined by the only amount of energy that can be saved. Technologies such as CCHP could represent the perfect answer to this problem, on one condition though: it must be taken into consideration the reliability parameter as well. The plant configuration should guarantee a service without any interruptions. Redundancies must be evaluated and the consequences of the installation costs they imply. This study presents a method to make the right choice about an energy system characterized by: energy, reliability and economic services which satisfy power supplying to a polygeneration grid in a residential context. The case study is the area of Arci, near Rome, Italy. Our purpose is to realize a teleheating network and create a system able to satisfy the electric demands of the area. The first step is an accurate estimation of the electrical and thermal demands. Then we compare the optimized energy solutions with the traditional ones. Some changes have been introduced to improve the system's availability. All these steps take to an economic evaluation able to give some useful information about the feasibility of the technical choices previously made.
The European Union is working on strategies in order to increase the energy efficiency of buildin... more The European Union is working on strategies in order to increase the energy efficiency of buildings. A useful solution is to identify the energy performance of buildings through the Energy Performance Certificate (EPC), as it provides information for the comparison of buildings with different architectural typology, shape, design technology and geographic location. However, this tool does not assess the real energy consumption of the building and does not always take into account its impact on the environment. In this work, two different types of analysis were carried out: one based only on the energy efficiency and the other one based on the environmental impact. Those analyses were applied on a standard building, set in three different Italian locations, with the purpose of obtaining cross-related information. After the evaluation of the results, interventions on some parameters (walls insulation, windows frame, filler gas in the insulated glazing) have been identified in order to improve the energy behavior of the building with an acceptable environmental impact. The aim of this paper is to propose a methodology that integrates the EPC with green building rating systems, leading to a more conscious choice of retrofit interventions as a compromise between energy performances and environmental impact.
ABSTRACT Outdoor thermal comfort affects the health of the people and the quality of life in urba... more ABSTRACT Outdoor thermal comfort affects the health of the people and the quality of life in urban areas. This is the reason why in the past few years different mitigation strategies for the microclimate have been studied and examined. These strategies depend on those passive factors characterizing the urban setting that are able to affect the values of local meteorological variables, as the limit surfaces of the urban space (parterre and façades of the buildings). This paper examines the Cloister by Giuliano da Sangallo, which is part of the Faculty of Engineering of Sapienza University of Rome. The case study compares the present configuration of the Cloister with four other configurations characterized by some vegetation and materials with a high albedo by taking into consideration the PMV (Predicted Mean Vote) model. Microclimatic variables are calculated through numerical simulations performed by the ENVI-met software. Such a comparison is performed during a typical summer day. While examining the results it can be noticed how the strategy presenting the best results is the one with some vegetation, whereas the materials with a high albedo improve the microclimate if applied on surfaces characterized by a high sky view factor.
Uploads