Thermal Performance Of Buildings Research Articles

Thermal performance evaluation of phase changing materials in double glazing units for office buildings in Egypt

Abstract Nowadays glass curtain walls are used widely in modern buildings as they offer a significant aesthetic appearance and provide the building with natural lighting. However, their poor thermal resistance leads to excessive usage of mechanical systems to achieve thermal comfort which in turn increases the energy consumption in buildings. The proper integration of the unique properties of the PCM could effectively enhance the thermal performance of buildings therefore, the main objective of this research is to examine and validate the effect of using phase change material (PCM) on the building thermal performance especially when integrated with double glazing unit (DGU). The research examined comprehensively the effect of using PCM with DGU by undergoing a field experiment and comparing the results with a simulation model using Design Builder (DB) -energy plus simulation tool. After validating the simulation model, DB was used to examine the effect of using PCM double glazing unit with a multi-story office building in three different climatic regions in Egypt covering humid, mild, and hot arid regions. The results showed that using petroleum jelly as a PCM with DGUs will lead to a significant effect in reducing the usage of mechanical systems in cooling the building spaces by 8.91%, 8.62%, and 8.07% in Cairo, Alexandria, and Aswan consecutively from the total yearly cooling electric consumption.

Integrating green roofs and green walls to enhance buildings thermal performance: A literature review

Integrating green roofs and green walls to enhance buildings thermal performance: A literature review

Effect of local climate zone morphology on ventilation availability and thermal performance

ABSTRACT In urban areas, the constantly altering morphological environment gives rise to a local thermal environment significantly different from the climate of surrounding areas. This study uses the Local Climate Zone (LCZ) classification system to analyse these variations in the local thermal environment, focusing on ventilation availability and its impact on building thermal performance. LCZs, representing high- and medium-density building clusters, were analysed in a boundary layer wind tunnel set-up and a parametric analysis using RSM was done to explore the impact of urban morphology variables on ventilation availability in the Cradle Sc-stream tool. The ventilation data obtained from the CFD analysis were further used to morph the standard weather file of the representative location. Later thermal performance assessments using the morphed weather data and the standard weather data were carried out for a representative residential building in the TRNSYS tool. The results show that there is considerable variation in ventilation availability and thermal performance of built environment across LCZs and, apart from the LCZ morphology, variables such as Block staggering and wind incidence angle also cause this variation. The study shows that building thermal performance assessments might result in significant errors if the local thermal environment is ignored.

Window Bevel Shape Optimization for Sustainable Daylighting and Thermal Performance in Buildings

Thick insulation of external walls is the standard method for passive reduction in heating costs in residential buildings in the northern climate zone. However, increasing the insulation thickness worsens the lighting conditions inside the rooms. This work demonstrates that diagonal cuts in the insulation around windows (bevels) significantly increase the light entering the building without compromising its heat resistance. The optimized window bevel shape is a cost-effective method for improving daylighting in residential buildings. The research employs traditional finite-element modeling (FEM) alongside a novel method that allows for the simultaneous calculation of heat transfer and daylight distribution within the same simulation environment and geometry. The study analyzes the impact of various incision depths and angles on both daylighting and the thermal performance of the building envelope. The results show that the optimal bevel geometry dependent on the insulation thickness without a negative impact on thermal properties may be found. In addition, a traditional daylight analysis shows that for thick insulation, the introduction of bevels makes the difference between satisfactory and inadequate lighting conditions in the room. Moreover, reduced use of insulating material and resulting solar gains may significantly increase the overall sustainability of modern buildings.

Crucial impact of spectrum calculation on energy and daylighting performance of glazing windows

The rapid advancement of spectrally selective materials has enabled the development of smart windows that can regulate different bands of solar radiation. However, existing methods for calculating spectral properties vary, leading to inconsistent results when evaluating their light-electricity-heat-color performance. Therefore, this paper presents five methods for calculating window spectral properties, intending to compare and identify the most effective approach for assessing building thermal performance, energy efficiency, and daylighting. The methods focus primarily on the solar spectrum input and the glazing spectrum response. The solar spectrum inputs include the Beijing local solar spectrum, ASTM G173-03, and ISO 9845 (methods S1 to S3), and the glazing spectrum response methods differ based on whether they account for spectral selectivity and the choice of spectral weighting functions (methods S3 to S5). The findings reveal that variations in solar spectrum input have a minimal effect on window performance, while differences in glazing spectral response calculations significantly impact results. It is particularly evident in thermochromic windows, where discrepancies in energy efficiency, specifically in lighting load, can reach up to 67.21 %, and variations in dynamic daylighting performance, specifically in Useful Daylight Illuminance (UDI) below 500 lx, can be as high as 28.27 %. To provide more accurate assessment results of glazing windows, this study recommends using the spectral calculation method S1, which incorporates the local solar spectrum and applies the standard luminous efficiency function to the glazing spectrum response. This paper highlights that further refinement of spectral calculation methods will enhance their utility for performance evaluation and guide the reverse design of innovative window features.

Artificial Degradation of Two Wooden Species of Different Density and Their Use for Optimization of Thermal Comfort in Climatic Areas of Marine and Mesoandean Desert

Objective: The objective of this study was to evaluate the behavior of two species of wood of different density and the most commercialized in the southern regions of Peru: Schizolobium excelsum (pashaco) and Aniba gigantiflora (mohena), in order to choose the appropriate timber species for housing coating and contribute to thermal comfort. Wood is known to be a widely used material in construction due to its mechanical, aesthetic and sustainable properties. However, its durability is compromised by environmental factors. The degradation of wood can manifest itself in the form of cracking, erosion and discoloration, affecting its structural integrity and appearance. On the other hand, several studios have designed multilayered facades as an architectural strategy that seeks to optimize the thermal comfort of the interior spaces. Previous studies have shown that the configuration of multilayer facades with wood can result in a significant improvement of the thermal performance of buildings, for this purpose the best timber species must be chosen. Context: In this context, samples of two timber species were selected and evaluated in their natural state and coated with commercial surface protector, and wood thermally treated at 180 °C; these samples were subjected to accelerated degradation in a QUV equipment under conditions of UV radiation (0.89 W/m2 nm at 340 nm), humidity (by condensation and spray) and high temperatures (up to 60 °C), according to EN 927-6:2018 (European Committee for Standardization, 2018) for a total of 2016 hours. Results: The results showed statistically that the wood in its natural state, and with commercial coating presented cracking, fissures, erosion and discoloration. However, the heat treated wood presented better results of resistance against cracks. Finally, the species Schizolobium excelsum (density 0.33 g/cm3) is more resistant to exposed climatic conditions. Chosen the best timber species, it was configured as part of the multi-layer facade system composed of: heat treated wood, elastomer, air, OSB board and polyurethane insulators and its behavior was simulated to optimize thermal comfort in homes of marine desert climates and Andean meso with THERM software. The result showed an internal temperature concentration of 20 °C versus 0 °C of external temperature, this result considering only structures of walls of the house. Implications of the research: The implications of the research is at the level of material development, since the results reflect the need to develop coatings and treatments for wood that offer greater protection against degradation that respond to demands for durability and sustainability. Another implication is at the level of design strategy, the configuration of multi-layer facade with heat treated wood, can be adopted in architectural design to improve thermal comfort in marine or Mesoandean desert climatic areas. Originality: The originality of this inside research in which an accelerated degradation equipment was used, which allowed to have a realistic frame of reference to evaluate the behavior of materials in adverse climatic conditions. Likewise, it was possible to identify the timber species, more resistant to extreme climatic factors and by simulating the thermal behavior of this material, it is concluded that it is viable against other timber species.

A regenerative architectural solution for decarbonizing the construction sector in Algeria: lightweight and low-carbon insulating mortar

The building sector is responsible for a significant portion of greenhouse gas (GHG) emissions, thereby exacerbating climate change. To meet the growing need to minimize carbon footprints and improve construction energy efficiency, the development of eco-friendly building materials is crucial. This research concentrates on the development and assessment of lightweight insulating low-carbon mortar. This material is regarded as a prospective solution for regenerative architecture in Algeria due to its advantageous properties. This research aims to explore the characteristics of this material within the context of regenerative architecture, assessing its potential to enhance thermal insulation and energy efficiency of buildings and reduce CO2 emissions. This approach aligns with the principles of the "Materials" petal of the Living Building Challenge (LBC) certification, promoting architecture that goes beyond sustainability to become regenerative. To this end, we proceeded to make samples, conduct testing and laboratory studies on several specimens of this material, and perform digital simulations using RETA software. This mortar, is composed of low-CO₂ cement and lightweight aggregates, providing notable advantages in thermal insulation, energy efficiency, and GHG emissions reduction. In this way, it is observed that the thermal performance of buildings is improved, with a potential reduction in thermal energy consumption of up to 20% and a decrease in GHG emissions of up to 40% compared to conventional mortars. These, allows us to conclude that this ecological mortar contributes in initiatives that promote energy efficiency and sustainable development, promoting a transition towards more environmentally respectful regenerative architecture in Algeria and globally.

The influence of air velocity on thermal performance of buildings in the tropics

The influence of air velocity on thermal performance of buildings in the tropics

Role of phase change materials and digital twin technology in thermal energy storage system: A review

The exponential growth in energy consumption and demand, along with the depletion of natural resources, is exerting a catastrophic impact on global ecosystems. Recent advances in research and development have focused on the distribution of renewable energy sources and the reduction of traditional energy usage as strategies to address pressing environmental concerns, such as climate change and global warming. Moreover, there is an urgent need for appropriate technologies that can enhance the thermal performance of buildings, given the rapid increase in global cooling and heating demands. This study examines the role of phase change materials (PCMs) and digital twin (DT) technology in thermal energy storage (TES), drawing on an analysis of 89 research articles sourced from multiple databases and references. The findings demonstrate that TES systems optimized through meticulous selection of PCMs can effectively meet thermal comfort requirements. Integrating DT technology with building systems allows for the analysis of cooling effects and optimization of energy demand through DT models of smart buildings. The present study provides a comprehensive overview of the different PCMs used in cooling applications and explores the implementation of DT technologies within building systems. In addition, practical applications of DT technologies for TES systems are presented, providing insights into their potential for enhancing energy efficiency in building systems.

Innovative Strategies for Thermal Energy Optimization and Renewable Energy Integration in Net-Zero-Energy Buildings: A Comprehensive Review

The thermal performance and energy efficiency of buildings are critical factors in achieving sustainable energy systems as energy needs for heating and cooling are expected to represent more than 50% of global final energy consumption. This study analyzes conventional renewable energy systems for heating and cooling in buildings, focusing on strategies for developing net-zero-energy buildings. This review covers the integration of renewable energy, the use of intelligent energy management systems, and the optimization of thermal processes. It also compares various systems based on their advantages and limitations and analyzes emerging trends in the thermal management of buildings in different climate zones. The synthesis of recent literature highlights practical recommendations for achieving high thermal performance in buildings, including the importance of selecting appropriate energy systems based on local climatic conditions, optimizing system efficiency, and taking advantage of new materials and advanced technologies. This review aims to contribute to promoting sustainable construction practices with the integration of renewable energy sources and improving the energy efficiency of buildings.

Analysis of airtightness performance of residential areas in Mediterranean climate: Balıkesir houses

Airtightness is one of the crucial physical characteristics of building envelope that affect the building thermal performance and energy consumption. The airtightness of the building is influenced by the quality of workmanship and various design parameters such as window/wall ratio, type of joinery, size of the usage area, wall material, and thermal insulation on the external wall. In this study aiming to determine the airtightness performance of buildings in the Mediterranean climate of Balıkesir houses, airtightness conditions of 43 different houses were determined by blower door test measurement. The air exchange rate (n50) values of 43 houses/residences were obtained between 1.94 and 49.02 h−1 and compared with the current various standards. The effect level of the design parameters on the air tightness of the building envelope was obtained as a result of the analysis performed with analysis of variance and post hoc methods. According to the analysis, joinery type was the most effective design parameter in terms of airtightness, followed by usage area and transparency of facades. The result will help in deciding on the design parameters affecting the airtightness of the building envelope for energy efficiency in the Mediterranean climate.

3D PRINTING WITH NATURAL MATERIALS IN CIVIL CONSTRUCTION

The construction industry has experienced a number of transformations due to the use of digitalization and automation. Additive manufacturing, also known as 3D printing, is a current example. The purpose of this paper is to analyze the use of natural materials based on soil applied to 3D printing technology, with a focus on the thermal performance of buildings. A exploratory literature review was used to identify applied research that has explored these materials. The data obtained was systematized in a comparative table to identify the main strategies used. The analysis of applied research indicates that construction using 3D printing with materials based on soil is promising, taking advantage of the soil's natural thermal insulation properties and being able to incorporate parametric design and digital fabrication strategies to create complex, customized solutions for different contexts.

Optimization of building thermal environment and VR industrial heritage landscape design enhanced by computer vision algorithms

With the acceleration of urbanization, the optimization of thermal environment of buildings has become an important topic to improve energy efficiency and environmental sustainability. This paper aims to enhance the optimization of building thermal environment through computer vision algorithm, and explore its application in VR industrial heritage landscape design, so as to achieve the dual goals of building energy conservation and cultural inheritance. In this study, advanced computer vision technology is used to monitor and analyze the thermal performance of buildings in real time. Through the construction of thermal environment model, combined with deep learning algorithm to extract building thermal energy data, and use VR technology for visual display, so as to provide scientific basis for design decisions. The research objects include several representative industrial heritage buildings, and analyze their thermal energy consumption characteristics and optimization potential. The results show that the application of the computer vision algorithm reduces the heat loss of the building and significantly improves the energy efficiency. At the same time, the VR visual model intuitively shows the design effect after thermal optimization, enhancing the communication and understanding between designers and stakeholders. Therefore, the combination of computer vision and VR technology can effectively improve the optimization ability of building thermal environment and promote the sustainable design and operation of traditional industrial heritage.

Leveraging drone technology for enhanced thermal performance analysis in sustainable architecture: a case study of GBI-certified buildings in Malaysia

ABSTRACT In recent years, the realm of architecture has witnessed a significant transformation marked by a notable surge in focus on sustainable practices and energy efficiency. Architects and engineers increasingly recognize the innovative role of thermal efficiency in enhancing building performance. Such recognition emphasizes the critical importance of thermal analysis in understanding the thermal attributes of building materials and structures. Against this backdrop, this paper aims to bridge a current gap in architectural practices and sustainable design within the Malaysian context. It proposes a case study leveraging drone thermal mapping techniques on Green Building Index (GBI)-certified buildings. The study seeks to examine how architectural designs interact with environmental conditions and identify areas for improvement in sustainable building practices, particularly within Malaysia’s tropical climate context. The primary objective is to assess the effectiveness of drone technology in analysing building thermal performance and to explore how the findings can inform design interventions to enhance sustainability. To achieve this, a structured methodology comprising five procedural phases is employed in a case study focused on three iconic GBI-certified buildings in Putrajaya, namely Putrajaya Holdings Tower, Energy Commission Building, and Heriot-Watt University Malaysia. By integrating thermal imaging with visuospatial data and 3D modeling techniques, the study demonstrates the effectiveness of drones in analysing heat patterns, highlighting their potential as a tool for strategic design interventions. As an exploratory study, this paper serves as a catalyst for further investigations into the integration of drone technologies with architectural design, particularly within the context of tropical climates.

The Effect of Vernacular Adaptation on Thermal Energy in Semarang Architectural Houses

Semarangan vernacular houses mostly have acceptable thermal performance, primarily related to the roof design and its elements. However, some developments associated with the quality of comfort have already been in progress. We found modifications with an alternative opening in the roof. Testing is needed to determine whether this alteration of a vernacular house with roof modifications is suitable to synchronize to nature and culture for its sustainability. This research aims to assess the quality of the modification for the thermal and energy performance of Semarangan vernacular houses in responding to climate change based on innovation. We utilize an energy audit simulation using the SketchUp software and the Sefaira plugin extension to measure thermal shape and variables. The focused study analyzes the thermal performance of buildings through analysis of the building envelope and building shape from a conceptual model. We discover that vernacular modifications do not reveal any extreme differences. Further research is needed to examine some other types of modifications further. We have to ensure that any modification maintains the quality of the house's performance and even have to increase it.

Improving the building's thermal performance by using untraditional building blocks

AbstractIraqi buildings consume high-level electrical energy for air conditioning purposes to provide the standard human comfort condition. This paper adopted an experimental study by using Styrofoam adhesive or white cement as an alternative to ordinary Portland cement to manufacture building blocks with dimensions of 200 × 200 × 200 mm containing an internal core with dimensions of 90 × 130 × 130 mm, which were filled by using corrugated scratch-up or closed air gap. The samples were divided into two sets: the first had an aluminium foil layer applied to the external surface of the samples (reflective surface), while the second was without any layer (ordinary surface). The samples were tested under the climatic conditions of Baghdad city during the summer months (May to September) of 2021. These blocks were also evaluated by different structural tests. It can be seen from the test results that the use of Styrofoam adhesive with a reflective surface with panels of corrugated scratch-up increased the thermal insulation of the wall. It leads to reduce thermal leakage and the electrical energy consumed to provide comfortable thermal conditions by 52.7%, in addition to decreasing the mass density by 14.1% while compressive strength decreased by 21%.

Characterization and Energy Performance of WO3 Doped and Undoped Photochromic Films

When exposed to light sources, photochromic (PC) materials change their optical properties and can lessen the transmission of UV and infrared radiation. This results in optimal thermal comfort and a pleasing visual contrast between the internal and external settings. This study uses computer modeling to analyze the annual energy usage in a home with natural ventilation in order to compare the effectiveness of photochromic films with commercial glass. The study is carried out using the EnergyPlus program in the cities of São Carlos and Cuiabá ‐ Brazil. Experiments and numerical simulations with data from doped and undoped tungsten trioxide (WO3) PC films are used in the study. Given the rise in energy usage and the pursuit of thermal comfort, this method is essential for assessing the thermal performance of buildings. Evaluations included a comparison of air conditioner performance and energy savings analysis, which leads to a noteworthy annual reduction in energy usage of up to 216.55 kWh and a 40% improvement in visual comfort. It is determined that PC film's dynamic behavior is the best option for comfort in terms of heat, illumination, and visual comfort.

Properties of foam concrete containing phase change material impregnated pumice

Energy consumption rises as a result of numerous electrical devices used to maintain thermal comfort of interior building areas. Using building materials with low thermal conductivity and density as well as an effective thermal energy storage plan can help to mitigate this. In order to enhance thermal performance of building, phase change material (PCM) was incorporated to foam concrete mixture in this study. Capric acid (CA)-palmitic acid (PA) eutectic mixture was prepared and impregnated with pumice (50 % by weight), a light and porous material. DSC results indicated that pumice/CA-PA composite exhibited a melting temperature of 22.84˚C and a freezing temperature of 20.85˚C, with corresponding enthalpy values for melting and freezing determined to be 85.4 J/g and 85.1 J/g, respectively. TGA analyses demonstrated that operational temperature of pumice/CA-PA composite was significantly below its thermal degradation temperature (194˚C). The prepared pumice/CA-PA composites were replaced with silica aggregate at different rates and incorporated in foam concrete mixture. Porosity and water absorption values rose as pumice/PCM content increased, yet there was a 7.2–41.1 % drop in dry unit weight when compared to reference. Compressive strength also showed a linear decrease and the lowest compressive strength value was recorded as 4.71 MPa in the presence of 40 % pumice/PCM. Thermal conductivity dropped from 0.487 W/mK to 0.167 W/mK, suggesting that foam concrete samples that were produced are all suitable as insulation materials. In peak solar radiation hours, PCM-impregnated pumice foam concrete (PFC) provided about 11.8 % and 8.72 % surface and room center temperatures compared to that of the reference in maximum case. PFC with PCM provided 6.54 % warmer surface temperature in cold weather. PFC-PCM can provide a cooler indoor temperature during peak temperature hours. Therefore, it may have a great potential to decrease the cooling load of a building.

Machine learning-based predicting of PCM-integrated building thermal performance: An application under various weather conditions in Morocco

As is now stands, the building sector is among the “big three” significant energy consumer and greenhouse gas contributor in the world. Consequently, there has been a growing movement towards the development and adoption of renewable energy sources, energy efficient measures and energy management strategies. Phase change materials (PCMs) are considered as an alluring option for energy efficiency measures in building. In this paper, a case study building, based on typical residential construction in Morocco, was selected to assess the potential energy savings of adding PCM to the roof for twenty-four cities using the dynamic simulation tool, TRNSYS. Thereafter, thirteen machine learning techniques, including ANN, DT, SVM, ELM, GB, RF, TB, GLRM, GPR, LR, GAM, KRRM and LRR were assessed for predicting the hourly heating, cooling, and total energy consumptions. The models were trained and tested on a dataset that was gathered from the simulations in twenty-four locations in Morocco. The outdoor dry-bulb temperature, the relative humidity, the wind velocity, the wind direction, and the total solar radiation were considered as the key features. The obtained results revealed that using PCM, can effectively lower the total energy demand for all the cities under study, with exception for very cold climate given by Ifrane and Midelt, where the annual total energy consumption shows an increasing trend. Furthermore, comparing the statistical results for each machine learning model, it is found that the SVM model consistently outperforms all models and can be successfully employed to predict the hourly network's outputs of the building.

Enhancing Thermal and Daylight Performance of Historic Buildings with Passive Modifications; A Tropical Case Study

Historical buildings worldwide hold immense potential for adaptive reuse within the framework of the circular economy, a concept gaining traction in the building construction industry for its role in reducing carbon emissions. Many of these structures boast passive building design strategies, which inherently lower energy demands. Among these, thermal mass and daylight harvesting emerge as pivotal strategies for achieving indoor thermal and visual comfort, respectively. However, with the advent of significant climate change and evolving built environments, the efficacy of these historical passive strategies is subject to debate. This study focuses on a residential building constructed in the 17th century by Dutch settlers in Galle, Sri Lanka, serving as a case study. The research targets improvements in both thermal and visual comfort. Thermal performance analysis was conducted through air temperature measurements, revealing a notable 3-hour time lag and a 2.5°C reduction in peak air temperature during the day. Conversely, nighttime measurements indicated a rise in indoor temperature compared to ambient conditions. Using Design Builder software, the building was modelled to assess its daylighting conditions. Drawing upon thermodynamic principles and daylight harvesting techniques, the study proposes building envelope interventions and ventilation strategies to address nighttime overheating and enhance daylight utilization. The results demonstrate that these modifications can potentially reduce nighttime heat by 2-3°C, while also decreasing the energy requirement for lighting comfort from 51.10 kWh/m² per annum to 44.84 kWh/m² per annum. This research showcases the effectiveness of judiciously implemented interventions in historical buildings, illustrating tangible improvements in both thermal/visual performance and energy efficiency. Leveraging inherent qualities of historical structures and integrating modern design strategies to these buildings can play a vital role in sustainable urban development and energy conservation efforts.