Building Systems Research Articles

Simulation and analysis on heat leakage structure of cold compressor in large-scale refrigeration system

Large-scale helium cryogenic refrigeration facilities are indispensable equipment for many cutting-edge researches, and the cold compressor is the most advantageous pressurization scheme in superfluid helium systems with capacity of more than 200 watts. Due to the extremely low operating temperature zone of the cold compressor, the efficiency of the compression process decreases as the external heat leakage increases, especially when building systems with greater cooling capacity, this phenomenon becomes more significant. In order to reduce the influence of heat leakage, a conjugate heat transfer analysis is carried out on the cold compressor using commercial CFD software, and the internal structures, including thermal anchor, thermal insulation materials, are analysed and optimized base on the simulations.

Parametric study on the decarbonization potential of structural system and concrete mix design choices for mid-rise concrete buildings

Mid-rise reinforced concrete buildings are projected to continue being the predominant typology for urban development. Thus, reducing the carbon footprint of such buildings is critical for achieving a sustainable built environment. Reducing the amount of concrete and steel in a building through structural and mix design optimization is identified as a primary resource efficiency strategy. This paper is among the first to present evidence of the decarbonization potential of these dematerialization strategies on a building level. The study combines structural design choices such as slab system design, steel reinforcement optimization and span width with materials-based strategies, such as low binder concrete and low-carbon binders. For each scenario, material quantities are calculated following design prescriptions by EN1992–1–1 while state-of-the art life cycle inventory data are adopted to calculate the carbon footprint. Results show that shifting towards more efficient structural systems (i.e., waffle slab system) could save up to 20% of the carbon footprint on the building level compared to more traditional systems, such as slab on beams and flat slabs. In addition, reducing the spans from 7.5 to 5 m can save up to 20% more. Finally, the use of low-clinker cement in low-binder concrete can save another 50% in terms of CO2 impact per built-up area. Realistically, results of the case study concluded that implementing these three strategies could reduce the typical 232 kg CO2e/m2 value of the carbon footprint of structural elements of a mid-rise building up to only 58 kg CO2e/m2, i.e., a four-fold reduction.

Energy efficiency and thermal comfort characteristics of convection–radiation combined cooling system in office buildings

Energy efficiency and thermal comfort characteristics of convection–radiation combined cooling system in office buildings

Sustainable heating and cooling for residential buildings: coaxial ground heat exchangers

As the world fights climate change challenges and the soaring demand for energy-efficient solutions, the need for sustainable heating and cooling systems in residential buildings has become paramount. Traditional systems rely on fossil fuels and contribute significantly to greenhouse gas emissions. Ground source heat pumps (GSHPs) have emerged as a promising technology, offering a sustainable alternative to conventional space conditioning systems. Central to the success of GSHPs is the efficient and reliable operation of their ground heat exchangers, with lower installation costs, as a prospective solution for future residential applications. This paper presents a numerical axisymmetric (r-z) finite volume method solution of the thermal performance of coaxial ground heat exchangers (CGHE) that incorporate phase change material (PCM) in the ground for GSHP applications. An analysis of the CGHE with PCM grout is presented, highlighting the advantages of heat exchange performance over normal grouts. The temperature comparison on three different points in the grout with different grouting materials was carried out to analyse the behaviour of different grouting materials during the heat exchange process. The investigation from a temperature point of view showed that the inclusion of PCM in the grouting material improves the thermal performance of the CGHE.

A novel heating strategy and its optimization of solar–air source heat pump heating system for rural buildings in northwest China

In the rural areas of Northwest China, the utilization of clean and renewable energy is deemed a crucial measure for reducing building energy consumption and environmental pollutant emissions. This paper focuses on constructing a simulation platform for a solar-assisted air source heat pump heating system. A rural residential building in Yongshou County, Shaanxi Province, serves as an illustrative example. A novel flexible temperature control method with a feedback controller in sub-area and period is proposed in this paper, alongside the selection of three distinct objective functions aimed at optimizing the heating system. The simulation results indicate an average temperature of 17.0 °C throughout the heating cycle, with a peak temperature of 18.7 °C. Moreover, the solar fraction is measured at 25.11%, underscoring the significance of collector area and heat storage tank volume as primary factors in system design. The results also demonstrate that across various optimization objectives, the life cycle cost optimization scheme yields greater economic benefits, while the target building unit heating cost optimization scheme boasts the shortest static payback period and lowest unit heating cost. Conversely, the solar fraction optimization scheme stands out for its superior environmental benefits. These findings offer valuable insights for the design of heating systems tailored to diverse objectives.

Structural Assessment for Improving Energy Efficiency in Public Buildings

Abstract This paper explores the pivotal role of structural assessment in enhancing energy efficiency within public buildings. Structural assessment, a systematic evaluation of building components and systems, is essential for ensuring safety, longevity, and sustainability. By identifying weaknesses and improvement opportunities, structural assessment provides valuable insights for stakeholders to enhance operational efficiency and compliance with safety standards. The symbiotic relationship between structural integrity and energy efficiency underscores the significance of prioritizing structural considerations in sustainable building design. Material selection, design principles, and maintenance practices are crucial factors influencing energy performance. Structural assessments aid in pinpointing critical issues contributing to energy loss, such as air leaks, thermal bridging, and inadequate insulation. Recommendations derived from these assessments enable targeted interventions to improve energy performance and occupant comfort. Case studies of three schools highlight the tangible benefits of energy efficiency retrofits informed by structural assessments. These retrofits result in significant reductions in energy consumption, enhanced indoor comfort, and a diminished carbon footprint. A structured strategy for conducting seismic structural assessments and subsequent energy efficiency improvements is proposed, emphasizing the importance of a comprehensive approach to building sustainability. In conclusion, structural assessment serves as a linchpin for advancing energy efficiency in public buildings. By leveraging insights from structural assessments, stakeholders can drive transformative change towards a greener and more sustainable future, fostering environments that promote human well-being and environmental stewardship.

Deterrents to the IoT for smart buildings and infrastructure development: A partial least square modeling approach

Implementing Internet of things (IoT) technology in the context of intelligent buildings and infrastructure development has garnered significant attention within the construction sector. Nonetheless, the implementation of IoT could be improved by assessing various barriers. The purpose of this study was to examine the obstacles related to the adaptation of IoT techniques within the construction sector, as well as the effects on the advancement of intelligent building and infrastructure systems. The study employed a mixed-method approach involving exploratory factor analysis (EFA) and structural equation modeling (SEM) to determine six types of barriers: knowledge, technical, standardization, creativity, complexity, and economics. The study revealed that the implementation of IoT for developing smart construction and infrastructure in the construction sector was significantly influenced by all six constructs. The results of this study offer significant ramifications for the field. The study underscores the necessity for heightened consciousness and instruction regarding the advantages of implementing IoT. The study posits that the technical barriers, including interoperability, modernization of legacy infrastructure, and coordination and collaboration difficulties, require attention from the industry. The study highlights the significance of establishing industry-wide standards and protocols for implementing IoT and regulatory and legal frameworks. Finally, the study underscores the necessity for augmented funding and financing options for IoT endeavors. Subsequent study endeavors may expand upon the present findings by delving into the barriers encountered by alternative sectors and nations and assessing the efficacy of the suggested measures in this investigation.

Evaluating the influence of functional unit on life cycle assessment (LCA) reliability of concrete

The linear lifecycle of concrete, from production through usage to disposal, highlights its status as one of the most carbon-, energy-, and resource-intensive processes in the industry. The development of life cycle assessment (LCA) models to quantify concrete’s embodied and buildings’ operational emissions is strongly influenced by the selection of the functional unit (FU) since it dictates the magnitude and significance of the environmental burdens from concrete and buildings' life span. The chosen FU should comprehensively capture the concrete's functionalities and construction parameters. Nonetheless, establishing a FU that encompasses spatial, temporal, and intensity aspects of cement/concrete and its applications remains a significant limitation in the practice of current LCA models. This study analyzed the FU influence on the environmental footprint of concrete samples with specific compressive strengths (material level) via LCA. The LCA was conducted in OneClick LCA using the environmental product declaration (EPD) provided by the software for each ready-mix concrete sample. From the LCA results, the C 30/37 concrete mix (lowest compressive strength) exhibited the lowest carbon footprint for all the environmental indicators when a volume-based FU was considered. In contrast, the results were more favorable for the C 65/70 concrete specimen when the compressive strength (28 curing days) was chosen because less cement is needed to achieve one MPa of strength. This behavior was also observed in the modeling of a column in a building, where the mixture with the highest compressive strength (C 65/70) showed the lowest environmental impact for all the indicators. However, this assessment does not represent the actual building system's footprint. Thus, regionally specific functional units need to be established, considering not just concrete functionalities but also national regulations, stakeholder needs, and local resource availability.

Empowering human–environment well‐being through wearable sensing: Unveiling trends and addressing gaps in the energy transition

AbstractInteractions between individuals and their environment play a vital role in uncovering the energy usage of building systems and improving human well‐being. The use of technology, such as wearable devices, enhances the study of people's perception of their surroundings and helps to comprehend the factors that influence individuals' satisfaction in both indoor and outdoor settings. Despite the growing number of publications in this field, there is still a lack of comprehensive understanding and exploitation of wearable sensing potential in urban planning and building operations. To address this gap, this research conducted a bibliometric review of 1661 scientific studies on the topic, identifying trends and areas where wearable applications for human‐centric well‐being research in the built environment are lacking. The analysis of keywords revealed a focus on the application of data analytics to process the vast amount of information collected through wearable sensors. However, the complexity of the subject necessitates cross‐disciplinary and international collaborations, which are still in their early stages due to a variety of reasons. Additionally, there is a lack of research exploring the potential of multidomain studies and long‐term monitoring. When considering outdoor environments, the use of people‐as‐sensors through wearables can significantly contribute to the development of resilient urban planning and environmental risk management in smart cities. Wearable sensing technologies offer valuable insights into people's experiences and preferences, but further research and collaboration are needed to fully harness their potential in urban planning and building operations toward the energy transition. By embracing these technologies and exploring multidomain research, more resilient and human‐centric environments could enhance well‐being of individuals in both indoor and outdoor contexts.This article is categorized under: Sustainable Energy > Energy Efficiency Cities and Transportation > Buildings

Design of proactive management system for residential buildings by using smart equipment

This study's object is an energy efficiency of residential sector. The work is aimed at solving the task to improve the energy efficiency of the housing sector by devising technical solutions for monitoring and managing energy consumption and microclimate parameters of buildings. The proposed proactive management system for residential buildings consists of multi-sensors measuring CO2, temperature and humidity, smart meters of heat and electricity consumption, and smart plugs. The equipment is combined into single system through an integration controller with remote user access through an interactive web interface. A feature of the technical solution is the ability to collect, process, visualize, and archive data on the consumption of energy, as well as on the key parameters of the microclimate of residential premises. The advantages of the system are its flexibility due to the possibility of integrating additional devices during operation, as well as the use of standard communication protocols, which enables the interchangeability of component elements. The implementation and testing were carried out under the conditions of a real pilot site. The use of the system in practice confirmed the efficiency and stability of the operation, making it possible to obtain data on the parameters of energy consumption and microclimate and devising recommendations for reducing energy consumption at the pilot site. It was established that the microclimate meets the requirements of the standards (air temperature is about 22 °С while relative humidity does not exceed 60 %). Decrease in energy consumption can be achieved by reducing the temperature of the heat carrier in the absence of residents, as well as by considering the influence of weather conditions. During periods of residents activity, an excess of the permissible level of CO2 was recorded, therefore, automatic ventilation systems should be provided in the apartments

Building integration of solar energy systems in Türkiye and world

Energy is one of the most important issues from the Industrial Revolution and in the Globalizing World. Energy is also a big problem for the Republic of Türkiye, which has made a serious industrial breakthrough in the last 20 years. Because Türkiye, which does not have rich fossil fuels like the Middle Eastern States or Russia, is a foreign-dependent country for its energy needs. It is known that fossil fuels will be depleted in the near future and waste materials generated as a result of energy production pose great threats to the world ecosystem. Therefore, in recent years, developed and developing countries have been developing investment projects for alternative energy sources instead of fossil energy sources. The most efficient and harmless of alternative energy sources is Solar Energy. It should be noted that the use of solar energy, which is so efficient for our world and more attractive than other alternative energy sources in terms of the energy size it produces, requires a certain technical knowledge. Because Türkiye is geographically located in the middle belt and due to its special location, the number of sunny days is much higher than in other countries. In this article, the reality of solar energy in Türkiye and its potential, the solar energy systems used and how they are integrated into buildings, and the advantages and disadvantages of these integrated systems is reviewed. In addition, some examples from some countries of the world will be discussed. Furthermore, projects of integrated solar energy application systems in buildings in Türkiye are reviewed, in addition to some suggestions and recommendations in this field.

Interactions between chaperone and energy storage networks during the evolution of Legionella pneumophila under heat shock.

Waterborne transmission of the bacterium Legionella pneumophila has emerged as a major cause of severe nosocomial infections of major public health impact. The major route of transmission involves the uptake of aerosolized bacteria, often from the contaminated hot water systems of large buildings. Public health regulations aimed at controlling the mesophilic pathogen are generally concerned with acute pasteurization and maintaining high temperatures at the heating systems and throughout the plumbing of hot water systems, but L. pneumophila is often able to survive these treatments due to both bacterium-intrinsic and environmental factors. Previous work has established an experimental evolution system to model the observations of increased heat resistance in repeatedly but unsuccessfully pasteurized L. pneumophila populations. Here, we show rapid fixation of novel alleles in lineages selected for resistance to heat shock and shifts in mutational profile related to increases in the temperature of selection. Gene-level and nucleotide-level parallelisms between independently-evolving lineages show the centrality of the DnaJ/DnaK chaperone system in the heat resistance of L. pneumophila. Inference of epistatic interactions through reverse genetics shows an unexpected interaction between DnaJ/DnaK and the polyhydroxybutyrate-accumulation energy storage mechanism used by the species to survive long-term starvation in low-nutrient environments.

Construction of a Spatial Equalization Assessment System for Medical Facilities

The spatial equalization of medical facilities can alleviate the wastage of medical resources and improve the efficiency of medical services. Therefore, it is necessary to carry out spatially balanced planning and assessment of medical facilities in cities. Existing studies on the balanced planning, design, and evaluation of medical facilities have been conducted from the perspective of hospital buildings in terms of spatial utilization efficiency, service satisfaction, and their physical environment on one hand, and from the perspective of regional planning of medical facilities in terms of spatial accessibility to medical facilities and the suitability of medical facilities to the social environment on the other hand. This study hopes to break down the boundaries of each perspective and effectively integrate the architecture, planning, and social well-being of medical facilities, taking spatial equilibrium as the core, in order to establish a spatial equilibrium system for medical facilities and achieve a spatial equilibrium-based assessment of the current state of medical facilities. First, the factors influencing the spatial equilibrium of hospital buildings with the support of the system and environment of hospital buildings are determined. Second, the indicators of the spatial equilibrium of hospital buildings are extracted through the consideration of influencing factors, and the indicator weights are determined by discussing the degree to which they contribute to the influence of the operation of hospital building spatial equilibrium systems, thus forming a system of equilibrium indicators for hospital buildings. Finally, a spatial equilibrium evaluation model for hospital buildings is established to assess the effects of equilibrium. The results obtained in this study provide insights into the regional planning of medical facilities and the design of hospital buildings.

Techno-Economic Analysis of the Heating System Robustness

A techno-economic analysis of different heating systems of a multi-apartment building is performed. The final energy savings and the economic benefit under different boundary conditions are investigated for a Passive House that has been realized and monitored in Innsbruck, Austria. Eight different system combinations are considered, varying the heat generation (direct electric (as-built), air/water heat pump (HP) and groundwater HP) as well as the size of the photovoltaic (PV) system. The systems are investigated with a building model with two different parameterizations: the pre-design stage and the model adapted to the monitored boundary conditions (BC: climate and user behaviour) and monitored energy consumption. The monitoring of the first two years of operation revealed a significantly higher space heating demand (29 kWh/(m2a) compared to 8 kWh/(m2a)). The most robust system (i.e. the system that performs best independent of the BC) for primary energy optimization is identified as an air-source heat pump with a 32 kWp photovoltaic system. This system also allows economic savings in case of high heating demand (adapted building model) and slightly higher costs in case of low heating demand (pre-design model). The groundwater-source HP is cost-effective only in scenarios with high heating demand due to significant investment and installation costs. Monthly primary energy factors are used to account for seasonal effects of the energy demand, providing an assessment of system efficiency that accounts for the so-called winter gap.

SWOT analysis of green building systems in real estate development

Sustainable and green facts are important for leaving a healthy environment for future generations. These facts are like sustainable development, sustainable city, green building, green economy, and so on. Green building is an innovative solution to sustainable urban planning problems. In this study, green building, sustainability, development processes are examined, and the opportunities and threats of green buildings with their strengths and weaknesses are determined by SWOT analysis. Besides, the construction cost and energy savings of a green building are compared to the traditional building. As a result of SWOT analysis, besides its significant strengths such as sustainability of green buildings, low energy consumption, and independence of energy consumption, high initial investment cost was determined as the most critical weakness. The increase in building values and the emergence of new business ventures are considered opportunities for green buildings, and the perception of green buildings as luxury is considered a threat. Ultimately, this study reveals the critical significance of transitioning towards sustainable construction practices, supported by compelling numerical evidence. Despite the initial higher investment costs, green buildings exhibit substantial long-term benefits, with the construction costs of the LEED gold-certified building calculated at 31,798,854.3 ₺ and the platinum-certified building at 32,390,841.0 ₺ in January 2024. Notably, energy savings of 47.7% and 61.6% were projected for the gold and platinum-certified buildings, respectively.

A Review and Thermal Conductivity Experimental Program of Mattress Waste Material as Insulation in Building and Construction Systems

The building and construction industry consumes a significant amount of natural resources alongside contributing to the generation of waste materials. Addressing the dual challenge of waste management and recycling in this sector is imperative. This study begins with a bibliometric assessment to identify waste materials used as insulation in building and construction systems. The assessment of 2627 publications revealed mattress waste materials were seldom considered. The aim of this research focuses on exploring alternative methods for repurposing mattress materials in construction, aiming to mitigate waste generation. While various materials are being recycled for building applications, this research emphasises the potential of incorporating recycled polyurethane foam (PUF) from mattresses as insulation products. A transient plane source (TPS) was employed to determine the thermal conductivity of waste mattress PUF obtained from a recycling plant in Victoria, Australia. The results exhibited promising thermal resistance, with a mean value of 0.053 Wm/K. However, optimal thermal performance was observed with increased thickness, suggesting that a thickness of 215mm aligns with industry standards for building fabric systems. Further research is required to comprehensively analyse moisture resistance and fire retardation of waste mattress materials. This paper presents key findings of current trends, limitations, and future research directions to the use of waste mattress PUF as an insulation material.

Varying Levels of Proficiency in the Delivery of Value Engineering Objectives among Built Environment and Allied Professionals in Kogi State, Nigeria

Value Engineering (VE) practices analyze designed building features, systems, equipment, and material selections to achieve essential functions and enhance results while reducing the life-cycle cost. Hence, the objective of this paper was to evaluate the varying levels of proficiency in the delivery of VE objectives among the Built Environment and allied professionals in Kogi State, Nigeria. Data were harnessed from 94 study questionnaires administered across strata of these professionals in the study area. It was found that Architects, Builders, Engineers, Estate Surveyors and Valuers, and Town Planners in the study area exhibited varied levels of proficiencies across specific value engineering objectives (VEOs), whereas project managers and quantity surveyors exhibited very high-, and high levels of proficiency in the delivery of all the ten VEOs respectively. The variation which is an indication of their diversified skills in project cost management and control was significantly determined by the ten VE objectives commencing with enhancing of project functionality and terminating with minimizing project operating cost. The study recommended project managers and quantity surveyors as first- and second choice professionals in value workshop facilitation, given their high levels of proficiency in the delivery of these VEOs.

Embodied carbon premium for vanity height: A case for the exclusion of decorative spires in the design of tall buildings

In measuring the height of a tall building, the Council on Tall Buildings and Urban Habitat (CTBUH) recognises three categories: “height to architectural top”; “height to highest occupied floor”; and “height to tip”. The “height to architectural top” category, which includes decorative spires, is used to define the influential CTBUH annual rankings of the “World's Tallest Buildings”. The inclusion of decorative spires in the category ranking has created an incentive for developers to maximise the vanity height of tall buildings, defined as the height difference between a tall building's architectural top and its highest occupied floor.The aim of this paper is to demonstrate the detrimental influence of spires and, by extension, vanity height on the embodied carbon of structural systems for tall buildings. This influence is evaluated using three tall building scenarios of varying heights (50, 70, and 90 storeys). Two finite element models, with and without spires, are parametrically designed for each scenario. All the modelled structural systems comprise a reinforced concrete tube-in-tube lateral load resisting system. A hybrid life cycle inventory analysis approach is used to quantify the embodied carbon of spires as well as the resulting increase in the embodied carbon of structural systems.The findings of this study indicate that even basic spires can lead to an increase of up to 14.2% in the embodied carbon of structural systems for tall buildings, underscoring the imperative to eliminate such elements in the design and construction of tall buildings to minimise overall embodied carbon.

Perancangan Homestay Moni Kecamatan Kelimutu Kabupaten Ende (Tema Arsitektur Neo Vernakuler)

ABSTRACT DOMINGGUS PITERSON BABO 2018320320. Moni Homestay Design, Kelimutu District, Ende Regency (Neo Vernacular Architecture Theme). Faculty of Engineering, University of Flores, Ende, 2023.. Mobile Number : 081339344579, E-mail : babosoni@gmail.com supervisor I : Ir. Dian Fitriawati Mochdar, ST., MT. supervisor II : Fabiola T.A, Kerong. ST., MT. Moni Kelimutu tourist destinations include culinary tourism, shopping tourism, and recreational tourism. This has a positive impact because the number of tourists coming is increasing. Therefore Homestay lodging is a very important element to support the existing potential. Homestay has an important role to introduce the character of each region. Ende Regency is one of the districts with many tribes and precisely in the Kelimutu sub-district, the local community highly respects customs and habits, so Moni's homestay is designed with the Neo Vernacular theme which aims to strengthen the identity and character of the local indigenous tribes. The application of this theme is dominated by wood elements as an aesthetic element of the building both in the facade of the building and in the atmosphere of the building space. Wood is the main material for building traditional Lio houses. So that the Homestay is designed to have the feel of the local environment so that people who stay at this Homestay feel the character of the local area. The methods used in this planning and design are 1). data collection methods include primary data (observation, documentation and interviews) and secondary data (literature studies and comparative studies); 2). The analysis method explains each analysis which contains field data, design criteria (theory), alternative analysis (alternative 1 and alternative 2), and responses (alternative selection). Analysis methods include analysis of design objects; site analysis; functional analysis (space organization, namely the organizational structure of actors, analysis of activities and space requirements (analysis of actors and actors' activities), room analysis (conditions, circulation, organization, relationships, size and zoning of space), shape analysis and analysis of building mass placement patterns; analysis building systems (structure and utilities); as well as analysis of regional regulations. 3). The design method includes design ideas and design concepts, namely the concept of neo vernacular architecture. The results obtained from designing Moni's homestay are based on a neo vernacular architectural approach which emphasizes more on building materials and site processing. The facilities built include the main facilities in the form of accommodation (suite room and standard type homestay), management building, as well as supporting facilities in the form of a cafeteria, photo spot, outdoor room and service area, parking. Keywords: Tourism, Homestay, Neo Vernacular Architecture

Design and Implementation of an Iot-Based Safety and Energy Efficient System

The paper provides a safe and power-efficient Internet of Things (IoT)-based solution. With the growing concerns about environmental sustainability and the demand for improved safety measures in today’s society, it has become critical to focus on building systems that decrease energy consumption and assure the safety of humans and the environment. The proposed system employs cutting-edge technologies and novel approaches that will result in optimal energy usage with minimal or no human involvement thereby assuring the safety of people. The proposed system leverages on existing IoT technologies and is comprised of smart sensors, energy-efficient gadgets, and a centralized control unit. Therefore, it is able to demonstrate cutting edge power control strategies including power gating and dynamic central power regulation which control the usage of gadgets to operate at optimal power levels vis-a-vis the real-time demand to achieve energy efficiency. The system is also able to collect data on occupancy, lighting, temperature, and power consumption trends which can assist in making data-driven choices that improve the usage of energy. The proposed system provides large energy savings without sacrificing user comfort by dynamically altering lighting, and cooling systems based on occupants and ambient factors. Multiple simulations and real-world trials in homes and institutions’ buildings were used to assess the efficacy of the suggested system. The findings revealed substantial reductions in energy consumption without jeopardizing safety.