1,721,010 research outputs found
Simulation of observed temperature field below a building in Bologna, Italy
Full text linkUrban settlements, whether single buildings or apartment blocks, influence near-surface ground temperatures. Heat transfer by buildings to the ground must therefore be considered when designing both vertical probes and energy geostructures in urban areas. However, assessment of ground temperature variability in urban areas is still uncommon for shallow geothermal energy purposes, the standard temperature gradient based on climatic conditions usually being employed during the design phase. Yet precise assessment of the heat transfer between buildings, infrastructures and the underground could improve the planning of geothermal systems. This work presents a numerical simulation of a finite-element model of heat transfer to the underground due to both a single building and climate conditions with the aim of reproducing the temperature waves at each depth. An isolated building in Bologna (Italy) was chosen since it allowed exact quantification of its influence on the ground temperature without external interferences. For this purpose, different boundary and initial conditions were applied to the ground thermal model and results were compared with historical data recorded over several years. The idea proposed in the paper for a single building can be considered as the baseline for further ground temperature assessment of wider urban settlements
Energy efficiency in food processing buildings: an integrated approach based on data monitoring, experimental analyses and computer simulations
No full textThe present research aims to optimize energy efficiency in food processing buildings, by means of integrated design. The work is divided in the following phases: data monitoring, data analyses, computer simulations, and experimental tests in a case-study winery. The goal is to study and design energy saving solutions tailored for farm wineries, and easy to be implemented by the farms. The study proved the effectiveness of the proposed solutions and showed the importance of an integrated design approach to optimize the building and its systems
Report on earthquake-induced failures of rural buildings aimed at future preservation strategies
No full textThe rural landscape is undergoing rapid changes, and catastrophic events, such as earthquakes, can speed up this mutation, bringing to a loss of its traditional signs. In May 2012. two strong seismic events bit the Emilia Romagna region, in northern Italy. Those earthquakes caused several damages and collapses to historical rural buildings, highlighting their high seismic vulnerability. In this paper. damages and collapses collected in the aftermath surveys on 22 rural historical buildings, are presented and commented. It was observed that in the area hit by the earthquake few recurrent typologies are present. and buildings of the same typology showed similar damage mechanisms. Therefore, in order to define the most typical damages affecting rural constructions, the building stock has been classified in different categories, based on plan distribution and intended use of each building. The first criterion suggests considering isolated and composed buildings. The second separates the structures in dwellings for residential use. stable-haylofts and buildings used for other minor services. The outcomes presented in this paper allowed to identify the rural building typologies most vulnerable to earthquakes and to define recurring deficiencies for the various categories. In general, the main reasons of the collapses can he ascribed to lack of effective connections between orthogonal walls, poor connections between floor elements and walls, and excessive flexibility of floor diaphragms
Retrofit interventions in non-conditioned rooms: calibration of an assessment method on a farm winery
No full textIn the Mediterranean area, most wine farms make use of unconditioned above-ground buildings for wine conservation and ageing. Those buildings are usually constructed without a specific temperature control design, therefore indoor temperature distributions and trends can be suboptimal for wine storage. At the same time, various elements (commonly available in farms such as straw bales and climbing plants) could be used to create cheap constructive solutions capable of improving building's thermal behaviour. This study aims to test the effectiveness of different retrofit interventions for thermal behaviour improvement in unconditioned above-ground farm buildings, referring to wine-ageing requirements. The alternative design solutions are evaluated through energy simulations, calibrated and validated on an Italian case study. The results show the importance of roof insulation, and the improved performance of the combination of more retrofit strategies. The proposed approach can be extended to other passive strategies and proves useful to provide information to optimize, or even avoid, conditioning systems
Efficacy of greenhouse natural ventilation: environmental monitoring and CFD simulations of a study case
No full textIndoor microclimate control is fundamental in greenhouse design, and vent dimensions and positions play a crucial role in natural ventilation management. This research considers an Italian greenhouse for horticultural production and aims at identifying optimal vent configurations and opening management procedures for indoor environment control, focusing on summer cooling. Numerical modelling of airflows and temperature distributions was carried out through finite element CFD software, with streamline upwind discretization schemes for advection terms. Calibration of the numerical modelling was performed by comparing data collected in controlled environmental condition with simulations results. The automatic vent opening system of the greenhouse is programmed to fully open all the windows of each span when indoor air temperature overcomes a threshold value. Numerical simulations were performed to assess the efficacy of this solution in comparison with alternative strategies. Various configurations of roof vents were tested, with side wall vents always open. The best performances were obtained with windward roof vent closed, which entailed 64% of the maximum heat removal achievable through natural ventilation. The other possible scenarios considered showed a performance index of about 50%. The results suggest therefore to enhance the vent control system by considering also wind direction as input
Two-Step Optimization of Envelope Design for the Reduction of Building Energy Demand
No full textThe path towards nearly-Zero Energy Buildings has enforced stricter constraints in construction design while promoting the investigation of new architectural solutions, in residential and producing sectors. Energy simulations, integrated with machine learning, helps academics and professionals to investigate novel strategies for energy saving. We present here a 2-step methodology based on genetic algorithms, aiming to reduce the energy consumption for indoor heating and cooling, while identifying the most suitable commercial solutions for external wall and roof constructions. We compare it with a 1-step optimization algorithm with the goal to determine pros and cons of both methodologies. Even if the two methodologies are comparable in terms of energy reduction, the 2-step algorithm is less computationally expensive and finds several plausible architectural solutions, with equivalent energy profile
A Quantitative Physiognomic Analysis of Contemporary Farm Buildings to Improve Awareness in Rural Planning
No full textOrdinary citizens and stakeholders are gaining increasing awareness of rural landscapes as a common good, where architectural quality is an integral part of the environment. While historic rural buildings represent an acknowledged landscape value, this does not apply to contemporary buildings, which up to now have been considered service architecture to support the production of material goods. This study developed a method for analyzing the formal characteristics of contemporary farm building that adds quantitative aspects to the qualitative descriptions with the application of analytical tools. In particular, this work presents a validation and implementation of the methodological model FarmBuiLD (Farm Building Landscape Design) through application to contemporary rural buildings (constructed after World War II) in the Emilia-Romagna region of Italy, as well as a study of the relationships between the formal features and functional requirements of contemporary rural architecture. The results show how the contemporary rural architecture is diversified in terms of shape, relationship with the surrounding landscape, and articulation or compactness. Physiognomic clusters were defined on the basis of joint interpretation of the results. They allowed definition of the correspondences between physiognomic characteristics and specific functional requirements expressed by users of the rural landscape. This research also shows how the application of analytical tools can increase knowledge of contemporary farm buildings
ANALYSIS OF AN UNDERGROUND CELLAR THERMAL BEHAVIOR BASED ON ENERGY SIMULATIONS
No full textThe present study aims to assess the suitability of a non-conditioned underground room to keep and preserve the wine. In the last years simulation software helped the professional to predict temperature trends in aboveground buildings. Usually calculation precision and accuracy is not guaranteed for underground rooms. In order to assess suitability in underground rooms, this work calibrate an ad-hoc model and use it for the temperature prediction. Specifically the work, based on an Italian case-study, evaluates three models of the same underground cellar for predicting surface and air temperature trends. The differences among models came from different hypothesis of ground data availability. The results returned by EnergyPlus simulations are compared to case-study monitored data and undergo a procedure of validation and acceptability. The work shows the three model simulations are reliable and return acceptable results according to the proposed method, demonstrating moreover EnergyPlus program can be used also for heat exchange between ground and building. Finally the best fitting model have been used to predict room temperature trends throughout one solar year
An Alternative Modular Wooden System for Fast Assembly/Disassembly of Buildings
Full text linkThroughout human settlement history, the pursuit of durability has been a paramount objective in building construction. The emphasis on durability has resulted in the construction of buildings designed to outlast human lifespans. However, the lack of consideration for building demolition and disposal during the design and construction phases has created challenges for future generations. This oversight contributes to the environmental impact of structures after demolition, which is a significant concern given that the construction industry is a major contributor to energy consumption, CO2 emissions, and solid waste production. In fact, in recent decades, there has been an increasing demand for temporary constructions, driven by factors such as migration phenomena, natural disasters, and the COVID-19 pandemic, but also in sectors like agriculture, where seasonality and annual variations in activities require adaptable structures such as warehouses, barns, livestock shelters, and food storage facilities. Unlike traditional constructions, these temporary buildings must be assembled and disassembled multiple times during their lifespan. The challenge lies in ensuring the structural integrity, adaptability to varying conditions, and compliance with specific requirements to extend their usability and postpone the disposal phase. This study focuses on the design of a novel type of temporary structures intended for temporary needs such as emergencies and planned agricultural activities, resulting in a European patent. The structure is based on a glulam frame inside two OSB panels—that work as structural bracing, creating a hollow, resistant, light structure—connected with external steel connections. This work reports results of mechanical simulations and thermal transmittance calculations. Specifically, it demonstrates the building maintains structural strength through multiple usages and its thermal characteristics can be easily adapted to the context. These are the first steps for a resilient and sustainable building
Analysis of the thermal loads required by a small-medium sized winery in the Mediterranean area
Full text linkSince the Nineties of the previous century winery design has been undergoing deep changes. Some factors are affecting the main design criteria, focusing on a new conception where the winery becomes more and more open to customers, energy demand reduction is a crucial goal driven by economic and environmental reasons, and the whole systems is aimed at the research of a renovate quality of the product. The state of the art in this specific sector highlights how a reduction of the energy consumed by a winery can almost reduce to zero the carbon emissions of the whole wine-making process, as well as the existing lack of specific design criteria addressing the most recent above-mentioned trends and challenges, in particular for small and medium-sized farms, that on the whole account for a huge production in the Mediterranean area. The main aim of this work is to provide information about yearly thermal demand in the wine-making sector, by means of an integrated approach that considers the thermal loads required by room heating and air conditioning, must/juice pre-cooling, and fermentation cooling. Different models have been created and tested on a case study, in order to analyse the contribution of various farm design choices to the total energy demand. The most representative models are described and analysed in this work: they differ for harvesting modality, and materials and vertical distribution of the building envelope (aboveground vs underground). The results highlight the relevance of the three contributions in terms of total annual energy consumption, power peaks, and time distribution of energy demand over the year. The analysis of the data obtained by the different models have allowed to identify the strengths and potential critical issues, and to provide professionals, oenologists and farmers with useful elements to lend support in their decision making processes, as well as to define the next steps of the research, aimed at defining specific design criteria for small and medium-sized wineries
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