bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon and craft: Lessons from the deconstruction, relocation, and reuse of a traditional Japanese house’s timber structure
Authors: Fang D , Berglund-Brown J , Iwakuni D , Mueller C
Published: December 2023

This paper presents and analyses the Chair Laboratory in Kawaguchiko, Japan as a case study of structural reuse. An inventory analysis is conducted from collected data, followed by a life-cycle-cost analysis of deconstruction, transporting, and reassembling the structure. The results are compared to two alternative schemes (timber non-reuse and steel) to benchmark the savings associated with reuse. The material quantity take-down and life-cycle-cost analysis indicate a 46%-71% reduction in GWP due to reuse (on the order of 17-20 kg CO2e/m2 of savings), at the expense of a 39% increase in cost. The cost increase is dominated by additional labour-hours for disassembly and adjustments. This data presented in this reuse case study gives realistic quantitative and qualitative insights on the feasibility, benefits, and barriers to reuse. Policy-makers and designers can use these insights to inform policies and make design decisions that encourage structural reuse and, consequently, a lower-carbon built environment.
Low-tech methods for the reuse of reinforced concrete structural elements
Authors: Devènes J , Bastien-Masse M , Widmer N , Fivet C
Published: December 2023

Most of existing buildings are made of concrete, new buildings are being built with it and others are demolished when still in good structural condition. This drives increased demands for raw materials, greenhouse gas emissions, and an accumulation of demolition waste. When in-situ rehabilitation or transformation is deemed unfeasible, a promising circular economy strategy to reduce these impacts is to reuse reinforced concrete (RC) load-bearing elements from obsolete donor structures into new receiving structures. Consequently, there is a need to adapt methods and processes to the specificities of RC element reuse by integrating knowledge on existing structures, deconstruction and construction techniques and structural optimization. To facilitate the supply chain of reclaimed RC components, the planning and execution of the deconstruction of an obsolete donor structure must be linked to the planning and execution of the construction of a new receiving structure. Using three recent case studies in Switzerland, this paper highlights how low-tech methods and procedures can be used to plan RC element reuse. A complete set of tools is introduced to evaluate an existing donor structure, plan its optimal deconstruction, and design the new receiving building. They include a reusability assessment method, a reuse-driven design process, and a data validation procedure. The case studies confirm that, depending on transport distances, reusing RC elements in a new structure can save up to 75% of CO2-eq emissions compared to standard RC construction techniques.
A framework for semi-automated creation of Building Information Models for existing buildings
Authors: Triantafyllidis G , Huang L
Published: December 2023

The environmental impact of the building sector can be significantly mitigated by reusing materials and components from the existing building stock. Building Information Modelling (BIM) methodology can serve as a potent tool for the documentation, management of existing buildings, and foster effective collaboration among different stakeholders in the value chain of the building sector. In addition, by providing information about the building’s structure, materials, and systems, BIM enables more informed decision-making regarding potential renovations, retrofits, and repurposing. However, developing BIM models for existing buildings is a labour and time-intensive task. There is therefore the need to investigate possible ways to automate the data acquisition and the creation of BIM models. By using the extracted alphanumerical information from two databases in a BIM and Visual Programming Language environment, we develop a workflow that can read and transform this information, which is given as input, into a parametric BIM model. We then discuss the data availability and accessibility from those databases and what data requirements are still needed to achieve higher granularity for the BIM models. Finally, we develop a workflow, and we provide suggestions for further research and data integration. A shift into a circular economy model in the building sector could support reducing the environmental impact that the sector is causing. Developing BIM models by using a simpler method, could potentially facilitate informed decision-making for the reuse, recycling, and repurposing of building-materials and elements.
Reuse of concrete for the construction of a retaining wall: a case study
Authors: Collaud A , Mongillo M , Niederhäuser E L , Pathé J , Redaelli D , Buri H
Published: December 2023

A promising strategy to reduce the environmental impact of the construction industry is the reuse of structural elements resulting from the deconstruction of existing buildings. However, despite a growing interest from the academic and industrial communities, practical examples of the reuse of structural elements remain very scarce at present, especially in the case of reinforced concrete buildings, which generally consist of a monolithic load-bearing skeleton that has not been designed for dismantling or reuse. This paper presents the results of a study on the reuse of concrete blocks from the deconstruction of an existing building as components for the in-situ construction of a new retaining wall. A real case study is considered. It consists of a building constructed in the 1970s. The developer of the new building wishes to reuse parts of the old building to create a new retaining wall on the boundary of the plot, with a length of 105 metres and a variable height between 60 and 250 cm. The dimensions and shape of the concrete blocks can vary considerably depending on the deconstruction technique used. In order to take into account this aspect, as well as the variable height and the mechanical support of the retaining wall, alternative solutions have been analysed. This paper presents the conceptual design and preliminary dimensioning of these solutions, as well as a discussion of their ability to meet all the technical and normative requirements.
From concrete waste to walls: An investigation of reclamation and digital technologies for new load-bearing structures
Authors: Grangeot M , Fivet C , Parascho S
Published: December 2023

The research presented in this paper highlights current practices for the end-of-life of concrete and explores opportunities in using unaltered concrete rubbles from demolition for the digital construction of structural walls. Through research by iterative making performed by the authors, relevant upcycling processes and design strategies are identified and explored to shape new tectonics specific to reclaimed concrete rubbles with non-standard variable geometries. This iterative research proposes accessible and scalable digital processes to overcome the challenges inherent to this untapped construction material. Results from small-scale prototypes provide valuable insights for full-scale processes to advance the digitization of construction and alleviate its environmental impact.
A semantic data framework to support data-driven demand forecasting
Authors: Allan James , Mangili Francesca , Derboni Marco , Gisler Luis , Hainoun Ali , Rizzoli Andrea , Ventriglia Luca , Sulzer Matthias
Published: December 2023

This paper presents a prototype semantic data framework for integrating heterogeneous data inputs for data-driven demand forecasting. This framework will be a core feature of a data exchange platform to improve the access and exchange of data between stakeholders involved in the operation and planning of energy systems. Surveys revealed that these stakeholders require reliable data on expected energy production and consumption for strategic and real-time decision-making. A core feature of the framework is the application of semantic technologies for comprehending spatial and temporal data requirements of energy demand forecasting. This paper demonstrates an approach to meeting these semantic requirements through established data standards and models. The conceptual design process followed the following stages: surveying stakeholders, researching digital technologies’ capability, and systematically evaluating the available data. In this paper, we present a prototype based on simulated data. Inputs and results from the simulation model, extracted from open datasets, were structured and stored in a knowledge graph comprised of virtual entities of buildings and geospatial regions. Multiple virtual entities can be linked to a single real-world entity to provide a flexible and adaptable approach to data-driven demand forecasting.
Integration of heat sources for heat pumps of larger capacities
Authors: Wemhoener C , Meier C
Published: December 2023

Heat pumps are seen as the predominant future heating system in many scenarios. However, with increasing integration of heat pumps sufficient heat sources can be a major obstacle, in particular at higher heating capacities and in existing buildings. The paper investigates two strategies to overcome limitations of the most common individual heat sources outdoor air and ground by the integration of two or more heat sources in order to enable a monovalent heat pump operation. By an integration of the ground for peak load coverage and air as base load the borehole heat exchanger field can be notably downsized, overcoming space limitations for the drilling and noise limitations due to a downsized air source. Compared to the individual air source the performance can be increased, while the system costs can be kept. Also the second strategy of the regeneration of the ground source allows for much smaller borehole fields, and the regeneration source can be refunded by cost savings due to a reduced total borehole length. Thus, performed simulations confirm that heat source integration has the potential to overcome limitations of individual heat sources while exploiting performance and cost benefits due to synergies between the sources.
A comparative investigation between rule- and inverse model-based fault detection and diagnostics for HVAC control systems
Authors: Darwazeh D , Gunay B , Rizvi F , Lowcay D , Shillinglaw S
Published: December 2023

Fault detection and diagnostics (FDD) tools provide valuable information regarding system faults and deviation from expected operation. Most existing FDD tools apply rule-based fault detection algorithms that generate an alarm when a rule is met; however, these tools cannot evaluate the overall performance of a system. Inverse-model-based FDD algorithms can be deployed to complement the fault alarms triggered by rule-based building energy management systems (BEMS). This paper examines the faults detected by rule- and inverse model-based algorithms used to detect faults in multiple zone variable air volume air handling unit systems. The capability of the rule- and inverse model-based algorithms in detecting and diagnosing faults is demonstrated through illustrative examples using data from three commercial buildings in New Brunswick, Canada. The results show that inverse model-based algorithms could diagnose faults that were not detected by the rule-based FDD algorithms implemented in a commercially available BEMS tool.
Inspiration from animal’s collective behavior for home energy demand management
Authors: Badarnah L , Barakat M , Oliveira S
Published: December 2023

An interdisciplinary approach towards managing energy demand through users’ behavior is discussed, drawing on knowledge from studies on collective behavior in nature. Studies on home energy demand management have focused mainly on social, technical and, more recently, socio-technical aspects that are considered largely at the individual levels only. However, emerging trends in social studies call for explorations across different social and spatial scales beyond the individual levels. This work distinguishes several principles and mechanisms of collective foraging decision-making from nature that respond to demand, including aspects of self-organization and stigmergy. The scoping of potential biological systems and behavioral aspects emulation aims to provide a foundation for agent-based modelling (ABM). Collective behavior emerges from local interactions of the individuals within a group, and nonlinear interactions between individuals and their environment enable them to accomplish tasks, such as structural construction, without the involvement of centralized control systems. Response to demand in nature is significantly influenced by information flow, processing, perception, and communication and coordination patterns between individuals, groups, and their environment. By studying these interactions and adapting their principles to the context of home energy management, we can develop new, more efficient, sustainable, and resilient approaches.
Multi-criteria comparison of various drinking water installations for low-temperature supply systems in apartments
Authors: Pärisch Peter , Distelhoff Mark , Keuler Jonas , Lampe Carsten , Graf Christopher , Cadenbach Anna
Published: December 2023

Rules to prevent from legionnaires disease gain importance as the building sector, esp. multi-family houses, needs to be decarbonized with temperature sensitive heat pumps. As legionella grow often in the peripheries of the pipe networks, we carried out dynamic simulations with TRNSYS of four different piping designs with composite pipes inside a reference apartment (T-piece, in-series, ring and a mix of T-piece for potable hot water (PWH) and ring for potable cold water (PWC)). We applied PWH and PWC tapping profiles for each tap, investigated two different supply temperatures of potable hot water 60 °C and 45 °C, and compared the results using hygienic, comfort and energy efficiency performance indicators. Based on the indicators and the boundary conditions used, classical T-piece and the mix installation show the best results, followed by series and ring, especially when using decentral water heaters with 45 °C.
Comparison of building energy performance in three urban sites using field measurements and modelling in Kayseri, Turkiye
Authors: Toren B I , Sharmin T
Published: December 2023

Despite the fact that the interrelationships between urban microclimates and energy demand have been recognised, there are not many processes that combine microclimatic boundary conditions to estimate energy consumption in parametric morphological investigations. Therefore, this paper will demonstrate a simple step-by-step methodology to incorporate the effect of urban microclimate on building cooling energy demand in semi-arid climatic areas. In this study, the combination of ENVI-met, Urban Weather Generator (UWG) and Rhino grasshopper are used to investigate the connection between microclimate and energy in the climatic environment of Kayseri. This coupling’s potential is investigated across compact high-rise, midrise and low-rise buildings, focusing on the cooling requirement on the hottest days. The comparative study shows how and to what extent urban geometry, building height in this case, contributes to modifying the magnitude of microclimate impact on building cooling performance.
Assessment of operational and embodied energy in passive residential retrofitting strategies for the Mediterranean climate
Authors: Arancibia P Carrillo , Pagès-Ramon A
Published: December 2023

This study contributes to the research of lifecycle environmental impact in buildings’ passive strategies, specifically passive strategies incorporated during the energy retrofitting of residential buildings in the Mediterranean climate. With a simplified lifecycle methodology, this research considers operational and embodied energy and CO2 emissions calculations to compare the results of the two passive strategies and the existing dwelling. In a 50-year reference period, results show that the operational improvement gained with the passive strategy can be reduced or cancelled due to the consideration of the embodied energy and CO2 emissions attributed to the additional materials.
Estimating surface utilization factors for BIPV applications using pix2pix on street captured façade images
Authors: Duran Ayça , Waibel Christoph , Schlueter Arno
Published: December 2023

While techniques for assessing solar potential, particularly on roofs, are well-established, estimating solar potential on building facades often requires more work due to the complexity of urban features and the elaborate design of building facades. Existing methods to assess the solar potential of building facades often neglect the characteristics of individual facades. This study presents an image-based method for a more accurate estimation of the PV potential of facades. The proposed method is composed of four steps: (1) data acquisition, preprocessing, and manual labeling, (2) training a pixel-wise semantic image segmentation model based on Generative Adversarial Networks (GANs), (3) color content analysis of segmented images, and (4) estimating the annual solar energy potential. We apply the proposed workflow to several buildings in Zurich, Switzerland, and evaluate segmentation quality and resulting changes in façade surface utilization factors. In a comparative analysis between the widely used web-based solar potential assessment tools, Sonnenfassade, Global Solar Atlas and the simulation software Climate Studio, we demonstrate the downstream impact of surface utilization factors on resulting solar potentials. Considerable deviations in façade availability for BIPV deployments among the various tools as compared to our segmentation approach indicate the potential impact of the proposed method on policy-making and the benefits for BIPV design and planning.
Scalable façade-integrated PVT-systems for upward extensions in the urban context
Authors: Weidner P , Gerber A
Published: December 2023

This article presents a building concept, realised in a timber demonstration house. It is characterized by vertical, façade-integrated PVT collectors and a newly developed active layer as low-temperature storage system. We developed a scalable and transferable energy system design. Especially for multi-storey additions, where the roof area does not grow with the floor space, the concept increases - very much needed - power and energy density in urban areas. The novelty of the presented concept is the sole reliance on vertically mounted PVT-Panels as a heat source, without any seasonal energy storage (e.g., ice storage or geothermal) in combination with the active layer storage below the underfloor heating. Together they allow scaling of energy storage and solar gains with the usable space in the urban context of adding floors to existing buildings.
A mapping of electric construction machinery and electric construction sites in Norway
Authors: Wiik Marianne Kjendseth , Homaei Shabnam , Høyli Randulf
Published: December 2023

The Norwegian construction industry is responsible for ca. 2.2 million tonnes CO2eq in 2021. The rise in GHG emissions, noise and air pollution in the built environment is becoming a potential hazard due to the large growth of construction activities within cities. As a response, actors from the Norwegian construction industry have converted diesel construction machinery to electric operation to reduce these impacts. As a result, the electric construction machinery market in Norway has grown exponentially. However, access to electric construction machinery varies greatly. The aim of this paper is to map the available electric construction machinery on the Norwegian market as first steps towards creating a database of electric construction machinery for subsequent energy and power demand modelling of fully electric construction sites. This paper also maps the regional differences in construction machine availability through mapping the known public construction sites in Norway that use electric construction machinery.
Towards a novel intelligent and fully interactive IoT framework for residential buildings
Authors: Erfani Moghaddam M A , Konstantzos I
Published: December 2023

Intelligent operation of buildings plays a crucial role in enhancing energy efficiency, especially in commercial buildings. However, residential buildings suffer from lack of management in energy consumption, contributing to global carbon emissions. Challenges include limited autonomous features, lack of scalability, and costly existing solutions. This paper presents a preliminary study toward the realization of a universal, scalable, and low-cost residential control framework to improve energy performance and reduce the cost of existing building retrofitting approaches. The residential system in its envisioned form may include thermostat, dimming, shading, and window-opening controls. For this study, a preliminary simulation-based investigation of a typical house in multiple climates is performed. To this end, the occupancy profiles data to layout different levels of automation of thermostats and shades have been employed, proposing 3 levels based on a variety of thermostat setpoints and shading. Data from the American Time Use Survey is utilized to inform occupancy and form the integrated automatic control strategy. This approach paves the way for building management systems in homes that integrate IoT-enabled devices for seamless operation, supporting decarbonization and creating interactive and smart buildings. The results showed that from 15% up to 70% reduction in heating and cooling loads are obtainable. This underscores the great potential of implementation of smart control systems in residential buildings.
Integration of occupant voting systems and smart home platforms for collecting thermal feedback in indoor environments
Authors: Callegaro Nicola , Albatici Rossano
Published: December 2023

The assessment of indoor thermal comfort is increasingly shifting from statistical to personalized models and therefore there is a growing interest in collecting feedback on occupants’ perceptions and preferences. Occupant Voting Systems (OVS) are emerging as a widely used tool in Post Occupancy Evaluations (POE) but the level of occupants’ interaction with these data collection devices, their scientific accuracy, and the integration of feedback data with building management systems, especially in residential buildings, still need to be further explored. This paper presents a study conducted on five dwellings, located in Italy, where smart home switches were used as feedback buttons to collect the thermal sensation of the occupants. These buttons were integrated into an open-source smart home platform, MOQA. The developed system is described in its technical features, highlighting the amount of information collected, the response rate and its interoperability with smart home systems. The results show that OVSs still have limitations in terms of occupant engagement and it is still rather complicated to correlate ratings with environmental variables. However, an easier integration, here described, with smart home systems would partially overcome these problems, turning the OVS into a useful tool for both users and research purposes.
Assessing the impact of morphed CMIP6 climate model outputs on building energy performance simulations
Authors: McCarty Justin , Schlueter Arno , Rysanek Adam
Published: December 2023

In this paper we utilise the latest generation of climate change models from Climate Model Intercomparison Project 6 (CMIP6) to morph typical meteorological year (TMY) weather files. These morphed files are used in conjunction with a standard set of reference models for the climate zones in the United States. Building energy demand, comfort, and photovoltaic (PV) yield are all simulated and evaluated for how they can be expected to change under each climate scenario. We find that the shifts in various preference metrics may vary seasonally in both magnitude and direction. Additionally, the overall distribution of the change can be highly variable across the US climate zones. The results indicate that buildings, as designed now, may not be able to provide comfortable conditions in the future. Furthermore the impact of increased cooling demand will change how building-based PV electricity yield is utilised.
The use of synthesised data for the development of Digital Twin: Chalmers student house case study
Authors: Caceres Alex Arnoldo Gonzalez , Malakhatka Elena , Hellebro Holger
Published: December 2023

This research focuses on the development of a digital twin for a residential building using a synthesised data approach. The methodology involves five stages, with three of them dedicated to simulating different energy scenarios: actual energy consumption, passive house level consumption, and consumption after the implementation of smart building technology. The selected building is located at the Chalmers Technical University campus in Sweden. Synthesised data is used to simulate the energy demand of the building before and after renovation, as well as after the implementation of smart building technology. A custom agent-based simulation model is developed to simulate the impact of residents’ behaviours on the building’s energy consumption, and high-resolution data was analysed and synthesised to create a new dataset that was applied to the selected buildings. Finally, the results of the simulations were analysed and compared to assess the potential energy savings and improved energy performance achieved through the implementation of different scenarios. The study provides insights into the energy-efficiency of different measures for reducing energy consumption in residential buildings. The study provides insights into the energy-efficiency of different measures for reducing energy consumption in residential buildings. This research shows the potential of using synthesised data to assess and forecast changes in building stock transformation, even when real data are not available.
Towards positive energy islands – a Danish case study
Authors: Jradi M
Published: December 2023

The Danish island of “Ærø” has the ambition of becoming the first Danish island to be self-sufficient in renewable energy and CO2 neutral by 2025, as well as fossil fuel free by 2030. This work investigates the feasibility of re-designing part of the island’s energy system to become the first Danish positive energy island (PEI), evaluating various design scenarios and opportunities for improving and modifying the current energy supply and distribution scheme. The district is modelled considering all building specifications and characteristics and the energy supply systems using the urban scale modelling tool City Energy Analyst (CEA). A simulation of the base-case scenario is performed to calibrate the performance. Different energy improvement strategies targeting building envelopes and energy generation and supply systems are created and implemented in CEA. Six improvement packages are created and simulated. It is demonstrated that a PEI could be built in the district under consideration through a comprehensive energy improvement package of envelope-targeting techniques, energy system upgrades, and the expansion of renewable energy systems. The package includes LED lighting, heat pump installation, and photovoltaic-thermal units. This will enable meeting the annual net need for electricity while producing 20% excess heat.
Comparison between ENVI-met and ANSYS-fluent when used for microclimate simulation
Authors: Le Anh-Vu , Chan Ying-Chieh
Published: December 2023

Computational Fluid Dynamic (CFD) simulation is prevalent in urban microclimate studies. This study examines two popular CFD microclimate simulation software, ENVI-met, and ANSYS-fluent, through comparison and experimental validations. We used the Taipei climatic conditions from the weather station as a boundary condition for both software. The findings show a high coefficient of determination of air temperature and relative humidity between experimental measurement and simulated results. However, other details, such as the porous media effect and the overestimated radiation in the two tools, were inconsistent when comparing the radiant temperature. Results demonstrate that researchers should select an appropriate tool depending on the study’ aims.
Cluster analysis-based energy performance assessment for office building stock
Authors: Oh Ji Hyun , Kim Hye Gi , Kim Sun Sook
Published: December 2023

To achieve carbon neutrality at the national or city level, the energy performance and conservation measures of large buildings should be evaluated. However, the assessment of the energy performance of existing building stock is often based on annual energy use intensity calculated from energy bill data due to data acquisition limitations. This approach has limitations in analyzing seasonal effects and establishing effective energy conservation strategies. In this paper, we propose a novel energy performance assessment method for existing office building stock. Our method classifies monthly electricity, gas, and heat energy use patterns using clustering algorithms without requiring additional database construction beyond the National Building Energy Database in Korea. We discuss the clustering results and provide an application method to assist policymakers through a case study.
Building archetype characterization for mass-housing energy efficiency through a UBEM approach
Authors: Vallati A , Morganti M , Causone F , Mannucci S , Fiorini C V , di Matteo M , Muzi F
Published: December 2023

Building archetypes characterization is one of the main sources of inaccuracy in Urban Building Energy Modelling (UBEM). This study aims to implement an effective approach to developing a building archetype for estimating energy efficiency in social housing districts. The goal is to support researchers and decision-makers analyzing strategies for similar buildings, evaluate energy use in buildings, and design different retrofit scenarios. UBEM is a practical approach in large-scale building energy modeling used by researchers and stakeholders to analyze and develop different design and retrofit scenarios for buildings with similar construction features and occupancy. The archetype approach requires a subset of buildings representing a cluster with similar properties (e.g., building type, construction features, occupancy, and age), which is used to extrapolate the total energy consumption at the urban scale. The research focused on clusters of four in-line multi-story building types in Rome to conceptualize the study, characterized by reinforced concrete structures. The most diffused systems are the traditional building systems using a gas boiler and radiators for domestic hot water and heating. The model was implemented following a UBEM approach, relying on Urban Modeling Interface (UMI), a tool allowing the creation of building templates to evaluate their energy use at neighbourhood and city-scale. The overall results obtained in this study are described to characterize the archetype for the mass-housing building that researchers and administrations can use to evaluate different strategies for buildings with similar characteristics.
Study on the ancestral rules of bioclimatic urban fabric in southern Algeria
Authors: Mestoul Djamel
Published: December 2023

Our present research aims to assess the impact of some parameters of traditional urban fabric (ksar) in southern Algeria on thermal comfort. We took as an example the ksar of Timimoun, located in the Algerian Sahara which is characterized by an arid climate. In this research, we conducted a series of measurements of the main climatic parameters (air and surface temperature, wind speed and direction) for summer comfort, with different spatial and temporal resolutions. A number of these parameters (morphological aspects) such as H/W ratio and street orientation have shown limited effects on reducing air temperatures, while others such as covered streets, palm groves, shading, etc. appear to be more important and equivalent to effective tools for climate control within the traditional urban fabric (ksar).
Towards deep learning methods to improve photovoltaic prediction and building decarbonization in benchmarking study
Authors: Sow M C , Jouane Y , Abouelaziz I , Zghal M
Published: December 2023

High energy demand, energy transition, energy consumption control are challenges for the future, especially for Building Integrated Photovoltaic (BIPV). There is a great potential to harvest large amounts of photovoltaic (PV) energy on horizontal and vertical surfaces. However, this high potential is often hindered by the slow deployment of these panels, the complex integration into existing buildings, and the possible complex interactions between different factors, such as visualization and active projection of buildings in the decarbonization process. Building Information Modeling (BIM) offers complete and real generative building data that is used in our deep learning methods. Indeed, there is currently no framework for design linking photogrammetry, BIM and PV for BIPV. In this work, we propose artificial learning models, such as Deep Learning, to predict PV energy production for BIPV decarbonization. We determined the optimal prediction of PV production by testing and evaluating different models on a building case study. We compared the PV power generation prediction results with 3D simulation software for solar architecture.
Towards the implementation of Positive Energy Districts in industrial districts: an Italian case study
Authors: Marrasso E , Martone C , Pallotta G , Roselli C , Sasso M
Published: December 2023

Owing to the opportunity to provide an annual positive energy balance and net-zero carbon emissions, Positive Energy Districts aim at fostering the energy transition of urban city centres. To fully support the decarbonization of cities, it may be interesting to extend their implementation to other energy intensive districts, such as cities’ industrial areas. In this regard, this paper addresses the opportunity to apply the Positive Energy District concept within the industrial area of a city in the South of Italy. A mixed-use building, the industrial wastewater treatment plant and an office building have been involved as users and equipped with a 250 kW wind turbine and multiple photovoltaic plants installed on the roof of the buildings, in parking areas and in an unused land, for a total peak power equal to 466 kW. The renewable-based plants’ generation has been simulated in HOMER Pro® software, on a quarter-hour basis, and an energy and environmental analysis have been performed using users’ real electric load profiles. The proposed configuration allows to save 55% of primary energy and carbon dioxide emissions compared to the baseline case where users’ electric energy demand is fully met by the power grid. In particular, the primary energy saving is equal to 1 GWh/y and the carbon dioxide emissions reduction is equal to 150 tCO2/y.
Quantification of the impact of global warming on summer overheating risk in a residential building in urban areas in Belgium
Authors: Sharifi Mohsen , Shamsi Mohammad Haris , Ma Yixiao , Lauwaet Dirk
Published: December 2023

Climate change has resulted in an increase of average outdoor temperature worldwide. With the rise of average outdoor temperature and unprecedented frequent heat waves, the demand for cooling systems in residential buildings has risen even in countries such as Belgium with moderate climates. However, there is a trade-off to consider when it comes to cooling. While active cooling methods can effectively maintain thermal comfort, they also come with excessive energy use in comparison to passive cooling techniques. However, passive cooling methods can lead to thermal discomfort and health issues during heat waves. To better understand this balancing act, this paper uses building energy simulation together with the measured current and accurately projected future climate data with high spatial resolution to investigate and quantify the potential for overheating in a selected residential representative building in the Flemish region of Belgium. Optimal solutions for renovation of the building are investigated including a variety of weather scenarios to account for climate change and to provide future-proof solutions. Results indicate that the renovation strategy is not affected by climate change for this case study. High insulation level with passive cooling strategy provided minimum energy use and acceptable summer overheating below 100 hours for this case study. Active cooling with medium and light renovation measures come with acceptable thermal comfort while also result in higher total energy use up to 53%.
Towards sustainable energy consumption for occupants of buildings with collective heating systems
Authors: Cabezas-Rivière Enzo , Recht Thomas , Barlet Aline , Robillart Maxime , Bouville Mathieu , Sebastian Patrick
Published: December 2023

Global warming is forcing us all to reduce our fossil energy consumption. A quantitative survey of people using collective heating in France was conducted to determine whether collective heating hinders energy savings and limits their thermal comfort. The study shows that the existing environment (e.g., heating control devices, access to heating bills) is not suitable for the occupants. Furthermore, the results point out that behaviour is not considered, by occupants, as one of the main energy saving vectors. This is partly due to heating control devices that can be inconvenient to use and thus do not maximize their thermal comfort. Indeed, there is a large difference between the temperature residents want, and the one they get. Our study population reported that rooms are colder than people wish. To achieve sustainable energy savings, efforts should be made to better take into account their comfort while making the technical system more suitable to the occupants, for example, by improving access to and understanding of bills and replacing the current manual control valves with programmable and remotely controllable ones.
A multi-criteria review of mean radiant temperature evaluation models for urban thermal comfort
Authors: Merville A , Rodler A , Musy M , Rouchier S , Dufrasnes E
Published: December 2023

This article reviews the main tools used to simulate the mean radiant temperature (T

mrt
) under outdoor conditions. Urban environment complexity and the multiplicity of the radiative fluxes force models’ developers to simplify the problem. To summarize the common assumptions of these models, a graphical tool is proposed. In addition to the physical description, effective coherence of models as a tool for urban decision-making is analyzed. Based on this double vision, this article achieves a multi-criteria analysis of T

mrt
calculation. Nine tools (ENVI-met, Solene-microclimat, SOLWEIG, RayMan, CitySim, Ladybug-Grasshopper, VTUF, DART and LASER/F) are evaluated against five criteria. Three criteria relate to physics implementation: completeness of the considered radiative phenomena, representation of the environment and surface temperature modeling. Two criteria deal with the operational capabilities: consistency with the needs of city-planners and practical accessibility. These criteria highlight various issues, and in particular the conflict between user-friendly practicality and an accurate description of physical phenomena.
Systematic derivation of the fundamental solutions for couple stress theory
Authors: El-metwaly A R , Kamal M A , Rashed Y F , Ismail A S , Nasry H
Published: December 2023

Classical elasticity theory failed to produce accurate results given in agreement with the experimental results. As this theory fails at stress concentration near the gaps or holes, or materials with significant microstructure contributions as soil, composite material, and polymer material generally in aerospace materials. In order to improve accuracy, the consistent couple stress theory is used. In the consistent couple stress theory, the microrotation and macro rotation are equal, where the macro rotation is half the curl of displacement, and the couple stress tensor is skew-symmetric. In this paper, the fundamental solutions for couple stress elasticity are derived in a systematic way via the Hörmander technique. The used technique is characterized by its ease and also develops the Galerkin tensor used in many applications, for example, the transformation of domain integral, computing the body force in the domain without discretization. All necessary kernels for displacements and tractions are derived and given in terms of a generalized Galerkin tensor for further use.
Design and analysis of an electric tiltrotor unmanned aerial vehicle
Authors: Gebril Ahmed A , Kamal Ashraf M
Published: December 2023

The concept of tiltrotor aircraft has been around for over seventy years, but it was not until the last decade that the advancement in Unmanned Aerial Vehicle (UAV) technology has made them a viable option. Although the design requirements of such UAV are complex and require careful consideration, the potential benefits are significant. Motivated by their potential capabilities, this paper aims to present a complete procedure for designing an electric tiltrotor UAV that incorporates the attributes of both fixed and rotary wing aircraft, including all necessary mathematical formulations. The paper explores the diverse aspects of the design and analysis of tiltrotor UAVs, from conceptual, preliminary, and detail design to aerodynamics, performance, and stability analysis. The detailed weight analysis is performed using six different methods from different references to assess their applicability for use with electric tiltrotor UAV. After designing and selecting the UAV components, an iteration process is performed to check and resize the estimated design parameters.
Development and verification of AeroMech tool for rapid estimation of airplane aerodynamic characteristics during early design stages
Authors: Magdy Ahmed , Zakaria M , Farouk O , Kamal Ashraf M
Published: December 2023

The aerodynamic characteristics of airplanes (i.e., coefficients and derivatives) are essential for the airplane design and optimization process. Generally, accurate calculations of these characteristics are complex and time-consuming. However, the level of accuracy can be adjusted depending on the design phase, problem complexity, and available time for analysis. Thus, diverse tools ranging from simple analytical methods to complex numerical simulations are used to calculate these characteristics during different design steps. This paper presents an efficient tool to expedite the calculation of the aerodynamic characteristics of airplanes with acceptable accuracy based on a combination of analytical and empirical approaches. The goal is to develop a a program tool (AeroMech) that can be used during the airplane preliminary design steps to rapidly assess a large number of alternative configurations and select the best ones for further detailed analysis. For this, enormous empirical relations that are typically represented in charts are digitized and implemented in the developed tool together with the analytical-empirical equations to facilitate and speed up the calculations. Cessna-182 and Cessna-310 airplanes are selected as two case-studies to verify the developed tool against the most common tools such as Digital DATCOM and XFLR5. Finally, the developed tool is partially validated with the available published experimental data for the case-study airplanes. The results show that the tool is able to predict the aerodynamic characteristics with reasonable accuracy for the preliminary design steps, which saves time and resources in the early design stages.
Numerical study of inlet air conditions on methane flameless combustion characteristics
Authors: Khodir A K , El-Behery S M , Elaskary A H
Published: December 2023

The current study investigates the influence of inlet air momentum and temperature for flameless characteristics. Three-dimensional computations were implemented by ANSYS FLUENT. A small-scale experimental combustor geometry was used for validation study. Turbulence modelling was performed by RNG k- ε model and the GRI-Eddy Dissipation Concept (GRI-EDC) model was used for the combustion modelling. The influence of inlet air velocity was investigated through using different air jet diameters at constant flow rate. Five different air jet diameters (4,6,8,10 and 12 mm) were studied. It was found that decreasing air jet diameter leads to an increase in the exhaust gas recirculation which reserve in mixture dilution (low O2 content mixture) subsequently, the reaction rate decreases which support the flameless mode creation. Also, this recirculated gas participates in heating up of fresh reactants which make the mixture tends to complete combustion. The influence of combustion air preheating temperature on NO and CO emissions were studied. CO and NO concentration were decreased with reducing the temperature of inlet preheated combustion air.
CubeSat attitude control via linear quadratic regulator (LQR)
Authors: Helmy M , Hafez A T , Ashry M
Published: December 2023

The interest in space-related activities has grown recently on a global scale. The determination and control of attitude are necessary all space duties. As it affects the satellites mission accuracy, many researches are related to it. Attitude control systems (ACS) design and modelling are represented in this paper. The mathematical models for CubeSat and reaction wheels that act as actuator and the proposed optimal control system are introduced. The proposed controller is applied to control and stabilize the CubeSat through a set of reaction wheels. The simulation results show the superior results of the proposed controller compared with traditional control systems in the presence of external disturbances and white noise. The withdraws of each control system are presented through the simulation results. The main contribution in this paper is solving the attitude control problem for a CubeSat using LQR approach in the presences of disturbances and noise.
Streak detection in astronomical images based on convolutional neural network
Authors: Elhakiem A A , Ghoniemy T S , Salama G I
Published: December 2023

Streak detection is important in space situational awareness and space asset protection. It is desirable to detect moving targets (e.g., satellites, space debris, or meteorites) in images of the sky. This paper presents a comparison between two astronomical frameworks for streak detection based on deep CNNs. The first framework uses the extended feature pyramid network (EFPN) with faster region-based CNNs (Faster R-CNN) and compares it with the second framework that uses the feature pyramid network (FPN) with Faster R-CNN. Because there aren’t enough publicly available astronomical data sets, we use the simulated data set to train the neural network. The metrics of mean average precision (mAP), recall, precision, and F1 score were used to measure the performance of the two frameworks. The experimental results confirmed that the EFPN-based framework achieves a significant improvement in streak detection than the Faster R-CNN framework based on the FPN model.
Designing attitude controller for nano/pico satellites at detumbling mode using magnetic sensor and actuator
Authors: Mohsen K , Ibrahim M , Kamel A M , Ashry M
Published: December 2023

Recently, satellites have been becoming economically attractive in many applications using the advanced technologies and payloads. Practically, the launching process of any satellite passes through some stages under different conditions. For example, the satellite might be uncontrollable in the detumbling mode. Thus, it might be a risk of accident with space debris and the satellite can not complete the specified mission. So it is necessary to design an attitude controller to stabilize the satellite after the separation phase, i.e., in the detumbling mode. In this paper, we design an attitude controller to bring the satellite to the desired condition with a minimum angular momentum. The magnetorquers and magnometers are an effective solution for the satellite in low-Earth orbits because they are smaller and lighter than others. Simulation studies are presented to validate the proposed attitude control approaches.