Pub Date : 2020-12-30DOI: 10.1080/17512549.2020.1860818
Paula Pico, J. Valdés, A. Pinilla, Adriana Echeverri, J. Gómez, N. Ratkovich, Bernay Cifuentes
ABSTRACT The management of Air Conditioning Systems (ACS) in Data Centre (DC) facilities has a significant impact not only on energy consumption but also on the performance and safety of the hardware. The main purpose of this work is to detect design and operational flaws of the ACS of a Tier 2 DC located at Universidad de los Andes (Colombia) with the aid of Computational Fluid Dynamics (CFD) tools. To achieve this objective, in situ measurements of air humidity and temperature were taken to develop and validate a CFD model. In addition to the current operation, two different scenarios were proposed, and their performance was evaluated in terms of the global temperature and relative humidity profiles, cooling efficiency with respect to the current operation, and air flow currents. The first scenario contemplated the operation of both AC units at full capacity for a normal 24-hour shift, and the second scenario contemplated an unsteady analysis of the AC’s operation on 12-hour shifts. The CFD and experimental results suggest that the DC’s layout and corridor arrangement have several flaws that cannot be overcome with the current ACS. Moreover, the CFD analysis carried out provides relevant insights into the performance of the operational setups tested.
数据中心(DC)设施中空调系统(ACS)的管理不仅对能耗有重要影响，而且对硬件的性能和安全也有重要影响。这项工作的主要目的是借助计算流体动力学(CFD)工具，检测位于哥伦比亚洛斯安第斯大学(Universidad de los Andes)的二级直流系统的ACS的设计和操作缺陷。为了实现这一目标，研究人员对空气湿度和温度进行了现场测量，以开发和验证CFD模型。除了当前运行之外，还提出了两种不同的方案，并根据全球温度和相对湿度曲线、当前运行的冷却效率和气流来评估它们的性能。第一个方案设想两个空调机组在正常24小时轮班时满负荷运行，第二个方案设想对空调12小时轮班时的运行进行不稳定分析。CFD和实验结果表明，直流直流的布局和廊道布置存在一些现有ACS无法克服的缺陷。此外，所进行的CFD分析为所测试的操作装置的性能提供了相关的见解。
{"title":"CFD modelling of the air conditioning system for a Tier 2 Data Centre","authors":"Paula Pico, J. Valdés, A. Pinilla, Adriana Echeverri, J. Gómez, N. Ratkovich, Bernay Cifuentes","doi":"10.1080/17512549.2020.1860818","DOIUrl":"https://doi.org/10.1080/17512549.2020.1860818","url":null,"abstract":"ABSTRACT The management of Air Conditioning Systems (ACS) in Data Centre (DC) facilities has a significant impact not only on energy consumption but also on the performance and safety of the hardware. The main purpose of this work is to detect design and operational flaws of the ACS of a Tier 2 DC located at Universidad de los Andes (Colombia) with the aid of Computational Fluid Dynamics (CFD) tools. To achieve this objective, in situ measurements of air humidity and temperature were taken to develop and validate a CFD model. In addition to the current operation, two different scenarios were proposed, and their performance was evaluated in terms of the global temperature and relative humidity profiles, cooling efficiency with respect to the current operation, and air flow currents. The first scenario contemplated the operation of both AC units at full capacity for a normal 24-hour shift, and the second scenario contemplated an unsteady analysis of the AC’s operation on 12-hour shifts. The CFD and experimental results suggest that the DC’s layout and corridor arrangement have several flaws that cannot be overcome with the current ACS. Moreover, the CFD analysis carried out provides relevant insights into the performance of the operational setups tested.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"231 - 261"},"PeriodicalIF":2.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1860818","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48263863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-28DOI: 10.1080/17512549.2020.1863859
A. Bahrami, F. Haghighat, A. Bahloul
ABSTRACT Vacuum cleaner is known as a proper way to remove settled dust or aerosols from surfaces to protect building occupants against abiotic and biological particles. In fact, the act of vacuuming the surface re-suspends a significant amount of dust and aerosols in the air. The other source of abiotic and biological particles could be the bag of cleaner and the motor of vacuum cleaner. The bag of the cleaners is the reservoir for microorganisms where they can grow, reproduce and become bio-aerosolized in case of penetration through the cleaner filtration system. Micro-organisms can disseminate from the bag, spread in the system and capture on the final filtration system where overshoot airflow can re-entrain the bioaerosol in the breathing zone which will cause catastrophe for all, especially those who are suffering from allergic and infectious diseases. The motor, due to arcing/abrasion of carbon, emits a significant number of nanoparticles, which can target our cardiovascular and respiratory organs. This review presents a summary of studies on vacuum cleaner and its effect on indoor air quality.
{"title":"Vacuum cleaner as a source of abiotic and biological air pollution in buildings: a review","authors":"A. Bahrami, F. Haghighat, A. Bahloul","doi":"10.1080/17512549.2020.1863859","DOIUrl":"https://doi.org/10.1080/17512549.2020.1863859","url":null,"abstract":"ABSTRACT Vacuum cleaner is known as a proper way to remove settled dust or aerosols from surfaces to protect building occupants against abiotic and biological particles. In fact, the act of vacuuming the surface re-suspends a significant amount of dust and aerosols in the air. The other source of abiotic and biological particles could be the bag of cleaner and the motor of vacuum cleaner. The bag of the cleaners is the reservoir for microorganisms where they can grow, reproduce and become bio-aerosolized in case of penetration through the cleaner filtration system. Micro-organisms can disseminate from the bag, spread in the system and capture on the final filtration system where overshoot airflow can re-entrain the bioaerosol in the breathing zone which will cause catastrophe for all, especially those who are suffering from allergic and infectious diseases. The motor, due to arcing/abrasion of carbon, emits a significant number of nanoparticles, which can target our cardiovascular and respiratory organs. This review presents a summary of studies on vacuum cleaner and its effect on indoor air quality.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"414 - 425"},"PeriodicalIF":2.0,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1863859","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43744819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-14DOI: 10.1080/17512549.2020.1731710
I. Banjad Pečur, M. Bagaric, Mark Bomberg
The primary function of the building has not been changed through the whole history of mankind – to provide shelter from the exterior conditions and provide the environmental control for comfort and health of the occupants. Despite the fact of having the same function, the requirements on building design are constantly increasing (high energy performance, airtightness, resource efficiency, healthy indoor climate, different aspect of indoor comfort – hygrothermal, visual and acoustic; etc.) making the building a highly complex system (building envelope, technical and service systems, automatization and control systems, interaction with occupants). In traditional approach, buildings were designed to meet certain, usually predefined, criteria of function and comfort, regardless of how they fit with the natural (local) surrounding. In this prescriptive design approach, buildings were designed and constructed for current conditions as ‘static’ structures isolated from their environment and the occupant. A paradigm shift in the integrated design implies changing the traditional design principles that are rooted in our codes and standards. We believe that the prescriptive thinking should be left in the past. A paradigm shift implies understanding that each building is a ‘dynamic’ system responding to, both outdoor and indoor climates. This new design paradigm is striving for a good indoor environment and high energy performance of building by interacting with the local climatic conditions and requirements of its use. At the same time, impact of building on the environment and its operating costs during the whole life cycle are taken into account, whereby durability of construction materials, building envelope systems, technical systems and building as a whole are put into focus. Performance-based design, that considers environmental, economic and social aspects, is in line with principles of sustainable development and thus, sustainability has become one of inevitable paradigms of integrated building design. New innovative technologies are constantly emerging, but they need to remain in the wellknown triangle technology-people-process, which means that integration of innovative technologies and strategies in buildings is good only if they are useful to the occupants, i.e. they are useful only if occupants are capable of using it. The paradigm shift towards integrated building design, also progressing towards dynamically operated buildings, facilitates integration of different professions in both design and construction. The interaction between different disciplines, high level of expertise and awareness are playing the key role. The importance of experience gained from previous failures has become crucial, especially when embracing digitalization and industry 4.0 in building design and construction. Many of the issues in building science, in context of energy efficiency, ecology, economy and social values as integral part of sustainability, have been ad
{"title":"Guest Editors’ Preface (Special issue “A Paradigm Shift in Integrated Building Design - Towards Dynamically Operated Buildings”)","authors":"I. Banjad Pečur, M. Bagaric, Mark Bomberg","doi":"10.1080/17512549.2020.1731710","DOIUrl":"https://doi.org/10.1080/17512549.2020.1731710","url":null,"abstract":"The primary function of the building has not been changed through the whole history of mankind – to provide shelter from the exterior conditions and provide the environmental control for comfort and health of the occupants. Despite the fact of having the same function, the requirements on building design are constantly increasing (high energy performance, airtightness, resource efficiency, healthy indoor climate, different aspect of indoor comfort – hygrothermal, visual and acoustic; etc.) making the building a highly complex system (building envelope, technical and service systems, automatization and control systems, interaction with occupants). In traditional approach, buildings were designed to meet certain, usually predefined, criteria of function and comfort, regardless of how they fit with the natural (local) surrounding. In this prescriptive design approach, buildings were designed and constructed for current conditions as ‘static’ structures isolated from their environment and the occupant. A paradigm shift in the integrated design implies changing the traditional design principles that are rooted in our codes and standards. We believe that the prescriptive thinking should be left in the past. A paradigm shift implies understanding that each building is a ‘dynamic’ system responding to, both outdoor and indoor climates. This new design paradigm is striving for a good indoor environment and high energy performance of building by interacting with the local climatic conditions and requirements of its use. At the same time, impact of building on the environment and its operating costs during the whole life cycle are taken into account, whereby durability of construction materials, building envelope systems, technical systems and building as a whole are put into focus. Performance-based design, that considers environmental, economic and social aspects, is in line with principles of sustainable development and thus, sustainability has become one of inevitable paradigms of integrated building design. New innovative technologies are constantly emerging, but they need to remain in the wellknown triangle technology-people-process, which means that integration of innovative technologies and strategies in buildings is good only if they are useful to the occupants, i.e. they are useful only if occupants are capable of using it. The paradigm shift towards integrated building design, also progressing towards dynamically operated buildings, facilitates integration of different professions in both design and construction. The interaction between different disciplines, high level of expertise and awareness are playing the key role. The importance of experience gained from previous failures has become crucial, especially when embracing digitalization and industry 4.0 in building design and construction. Many of the issues in building science, in context of energy efficiency, ecology, economy and social values as integral part of sustainability, have been ad","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"15 1","pages":"142 - 145"},"PeriodicalIF":2.0,"publicationDate":"2020-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1731710","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43734375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-11DOI: 10.1080/17512549.2020.1858961
M. Kazemi, L. Courard
ABSTRACT The use of recycled materials and porous aggregates such as rubber crumbs and volcanic gravel (pozzolana) for the drainage layer can lead to improving thermal behaviour of the green roofs. On the other hand, the thermal performances of green roofs can be affected by the thickness of substrate and drainage layer. Therefore, the main objective of this study was to adapt modelling characteristics for different thicknesses of substrate and drainage layers used under constant and variable temperatures and solar radiation: specific rubber crumbs and volcanic gravel behaviour has been modelled. The simultaneous heat and moisture transfers within the green roof were estimated as well. According to the results, the 9 cm substrate was recommended to be used for the green roofs, once the thickness of drainage layer was 4 cm. Moreover, the optimum thickness of pozzolana and rubber crumbs as drainage layer was 6 and 7 cm, respectively, once the thickness of the substrate was kept constant (5 cm). By increasing the thickness of substrate and drainage layers, the fluctuation of internal ceiling temperature in the green roof models with the presence of humidity decreased, but not as much as that in the green roof models without the presence of humidity.
{"title":"Modelling thermal and humidity transfers within green roof systems: effect of rubber crumbs and volcanic gravel","authors":"M. Kazemi, L. Courard","doi":"10.1080/17512549.2020.1858961","DOIUrl":"https://doi.org/10.1080/17512549.2020.1858961","url":null,"abstract":"ABSTRACT The use of recycled materials and porous aggregates such as rubber crumbs and volcanic gravel (pozzolana) for the drainage layer can lead to improving thermal behaviour of the green roofs. On the other hand, the thermal performances of green roofs can be affected by the thickness of substrate and drainage layer. Therefore, the main objective of this study was to adapt modelling characteristics for different thicknesses of substrate and drainage layers used under constant and variable temperatures and solar radiation: specific rubber crumbs and volcanic gravel behaviour has been modelled. The simultaneous heat and moisture transfers within the green roof were estimated as well. According to the results, the 9 cm substrate was recommended to be used for the green roofs, once the thickness of drainage layer was 4 cm. Moreover, the optimum thickness of pozzolana and rubber crumbs as drainage layer was 6 and 7 cm, respectively, once the thickness of the substrate was kept constant (5 cm). By increasing the thickness of substrate and drainage layers, the fluctuation of internal ceiling temperature in the green roof models with the presence of humidity decreased, but not as much as that in the green roof models without the presence of humidity.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"296 - 321"},"PeriodicalIF":2.0,"publicationDate":"2020-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1858961","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42531146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-11DOI: 10.1080/17512549.2020.1842802
Ljuboslav Boskic, Cory N. Brown, I. Mezić
ABSTRACT Current approaches to thermal control and energy management in residential and office buildings rely on complex or high-dimensional thermal models. We provide a means to extract features from in-office thermal-data sensors which avoid the use of standard models. We develop these data-driven methods through the use of Koopman operator theory. We validate our resulting algorithms via analysing thermal data from a single thermal zone space. The particular advantage of the method is that it associates the temporal characteristics of control mechanisms with the corresponding spatial zones of influence. The methodology enables identification of spatial heating and cooling control modes directly from the data.
{"title":"Koopman mode analysis on thermal data for building energy assessment","authors":"Ljuboslav Boskic, Cory N. Brown, I. Mezić","doi":"10.1080/17512549.2020.1842802","DOIUrl":"https://doi.org/10.1080/17512549.2020.1842802","url":null,"abstract":"ABSTRACT Current approaches to thermal control and energy management in residential and office buildings rely on complex or high-dimensional thermal models. We provide a means to extract features from in-office thermal-data sensors which avoid the use of standard models. We develop these data-driven methods through the use of Koopman operator theory. We validate our resulting algorithms via analysing thermal data from a single thermal zone space. The particular advantage of the method is that it associates the temporal characteristics of control mechanisms with the corresponding spatial zones of influence. The methodology enables identification of spatial heating and cooling control modes directly from the data.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"281 - 295"},"PeriodicalIF":2.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1842802","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48031758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-11DOI: 10.1080/17512549.2020.1844047
M. Alwetaishi
ABSTRACT Heritage buildings were built in a period when energy equipment for cooling and heating did not exist. This research focuses on the way in which we could benefit from such constructions to impact today's buildings and society. The investigation will consider a number of elements such as thermal mass, day-lighting and thermal comfort in comparison with a new simulated building which has the same design as the Heritage one. The research was conducted using the energy simulation tool TAS EDSL and on site measurement. In addition to that, an advanced thermal imaging camera was used in the study of physical characteristics of the building. The study revealed that applying methods of Heritage buildings to modern buildings, such as the use of thermal mass and natural ventilation, can have a considerable impact on energy consumption and thermal comfort for users. It can reduce indoor temperature up to 5°C. It was also found that the use of natural ventilation is linked to indoor thermal comfort. Large area of glazing is recommended to be used in such region when it is applied in the proper way.
{"title":"Can we learn from heritage buildings to achieve nearly zero energy building and thermal comfort? A case study in a hot climate","authors":"M. Alwetaishi","doi":"10.1080/17512549.2020.1844047","DOIUrl":"https://doi.org/10.1080/17512549.2020.1844047","url":null,"abstract":"ABSTRACT Heritage buildings were built in a period when energy equipment for cooling and heating did not exist. This research focuses on the way in which we could benefit from such constructions to impact today's buildings and society. The investigation will consider a number of elements such as thermal mass, day-lighting and thermal comfort in comparison with a new simulated building which has the same design as the Heritage one. The research was conducted using the energy simulation tool TAS EDSL and on site measurement. In addition to that, an advanced thermal imaging camera was used in the study of physical characteristics of the building. The study revealed that applying methods of Heritage buildings to modern buildings, such as the use of thermal mass and natural ventilation, can have a considerable impact on energy consumption and thermal comfort for users. It can reduce indoor temperature up to 5°C. It was also found that the use of natural ventilation is linked to indoor thermal comfort. Large area of glazing is recommended to be used in such region when it is applied in the proper way.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"214 - 230"},"PeriodicalIF":2.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1844047","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49511040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-23DOI: 10.1080/17512549.2020.1835712
A. Panagopoulos, Filippos Christianos, M. Katsigiannis, K. Mykoniatis, Marco Pritoni, Orestis P. Panagopoulos, Therese E. Peffer, G. Chalkiadakis, D. Culler, N. Jennings, T. Lipman
ABSTRACT Reliable, non-intrusive, short-term (of up to 12 h ahead) prediction of a building's energy demand is a critical component of intelligent energy management applications. A number of such approaches have been proposed over time, utilizing various statistical and, more recently, machine learning techniques, such as decision trees, neural networks and support vector machines. Importantly, all of these works barely outperform simple seasonal auto-regressive integrated moving average models, while their complexity is significantly higher. In this work, we propose a novel low-complexity non-intrusive approach that improves the predictive accuracy of the state-of-the-art by up to . The backbone of our approach is a K-nearest neighbours search method, that exploits the demand pattern of the most similar historical days, and incorporates appropriate time-series pre-processing and easing. In the context of this work, we evaluate our approach against state-of-the-art methods and provide insights on their performance.
{"title":"A low-complexity non-intrusive approach to predict the energy demand of buildings over short-term horizons","authors":"A. Panagopoulos, Filippos Christianos, M. Katsigiannis, K. Mykoniatis, Marco Pritoni, Orestis P. Panagopoulos, Therese E. Peffer, G. Chalkiadakis, D. Culler, N. Jennings, T. Lipman","doi":"10.1080/17512549.2020.1835712","DOIUrl":"https://doi.org/10.1080/17512549.2020.1835712","url":null,"abstract":"ABSTRACT Reliable, non-intrusive, short-term (of up to 12 h ahead) prediction of a building's energy demand is a critical component of intelligent energy management applications. A number of such approaches have been proposed over time, utilizing various statistical and, more recently, machine learning techniques, such as decision trees, neural networks and support vector machines. Importantly, all of these works barely outperform simple seasonal auto-regressive integrated moving average models, while their complexity is significantly higher. In this work, we propose a novel low-complexity non-intrusive approach that improves the predictive accuracy of the state-of-the-art by up to . The backbone of our approach is a K-nearest neighbours search method, that exploits the demand pattern of the most similar historical days, and incorporates appropriate time-series pre-processing and easing. In the context of this work, we evaluate our approach against state-of-the-art methods and provide insights on their performance.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"16 1","pages":"202 - 213"},"PeriodicalIF":2.0,"publicationDate":"2020-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2020.1835712","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43500129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1080/17512549.2019.1592706
Zhigang Zhang, Guanxiang Xie, T. Cao
ABSTRACT The wall implanted with heat pipes overcomes the contradiction between building energy efficiency and wall insulation by transferring the radiant heat from the sun to room during heating season and transferring the heat from room to outside during cooling season. This paper establishes the dynamic thermal transfer model of wall implanted with heat pipes (WIHP) in summer and simulates the dynamic heat transfer process. As revealed by the results, WIHP works 6.2 hours per day on average during the cold season. The rise in the average heat transfer from indoor to outdoor was measured to be 16.66 W/m2, and the surface temperature was found to drop by 2°C on average as compared to the conventional wall. In comparison, the new wall exhibited an improved capability in terms of heat dissipation, indicating that it was effective in lowering energy consumption and boosting indoor thermal comfort.
{"title":"Dynamic heat transfer analysis of the wall implanted with heat pipes in summer","authors":"Zhigang Zhang, Guanxiang Xie, T. Cao","doi":"10.1080/17512549.2019.1592706","DOIUrl":"https://doi.org/10.1080/17512549.2019.1592706","url":null,"abstract":"ABSTRACT The wall implanted with heat pipes overcomes the contradiction between building energy efficiency and wall insulation by transferring the radiant heat from the sun to room during heating season and transferring the heat from room to outside during cooling season. This paper establishes the dynamic thermal transfer model of wall implanted with heat pipes (WIHP) in summer and simulates the dynamic heat transfer process. As revealed by the results, WIHP works 6.2 hours per day on average during the cold season. The rise in the average heat transfer from indoor to outdoor was measured to be 16.66 W/m2, and the surface temperature was found to drop by 2°C on average as compared to the conventional wall. In comparison, the new wall exhibited an improved capability in terms of heat dissipation, indicating that it was effective in lowering energy consumption and boosting indoor thermal comfort.","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"14 1","pages":"403 - 423"},"PeriodicalIF":2.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2019.1592706","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45815731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1080/17512549.2019.1622154
L. Phan, Cheng-Xian Lin
ABSTRACT In the design of large-scale data centres, CFD is used widely but very time-consuming with intensive computational resource requirement. When it comes to near real-time thermal control or optimizing multiple design parameters of data centres, this method becomes impractical. In this paper, response surface methodology (RSM) based on radial basis function (RBF) is used to significantly reduce the running time while maintaining a good accuracy. In the first application, by using 5%, 10%, and 20% of the original CFD data, the temperature profiles of the three corresponding cases are reconstructed based on RSM. Three reconstructed temperature profiles are then compared to the full temperature profile of a data centre model. The method shows good agreement with the CFD simulation result, especially for the case of 20% utilization of the original CFD data points. In the later application, RSM is used for generating a large set of generations during a two-objective optimization process which uses the genetic algorithm as its main engine. With three investigated design parameters including mass flow inlet, inlet temperature, and server heat load, the goal is to minimize both the temperature difference and the maximum temperature inside the data centre. The outcome shows a desirable range of design input parameters for a data centre. Highlights Response surface model is trained using high fidelity CFD simulation data Radial basis function is found to show superior advantages in constructing response surface Rapid thermal profile reconstruction for data centre using response surface method is illustrated CFD-based response surface method for data centre optimization process is investigated
{"title":"CFD-based response surface methodology for rapid thermal simulation and optimal design of data centers","authors":"L. Phan, Cheng-Xian Lin","doi":"10.1080/17512549.2019.1622154","DOIUrl":"https://doi.org/10.1080/17512549.2019.1622154","url":null,"abstract":"ABSTRACT In the design of large-scale data centres, CFD is used widely but very time-consuming with intensive computational resource requirement. When it comes to near real-time thermal control or optimizing multiple design parameters of data centres, this method becomes impractical. In this paper, response surface methodology (RSM) based on radial basis function (RBF) is used to significantly reduce the running time while maintaining a good accuracy. In the first application, by using 5%, 10%, and 20% of the original CFD data, the temperature profiles of the three corresponding cases are reconstructed based on RSM. Three reconstructed temperature profiles are then compared to the full temperature profile of a data centre model. The method shows good agreement with the CFD simulation result, especially for the case of 20% utilization of the original CFD data points. In the later application, RSM is used for generating a large set of generations during a two-objective optimization process which uses the genetic algorithm as its main engine. With three investigated design parameters including mass flow inlet, inlet temperature, and server heat load, the goal is to minimize both the temperature difference and the maximum temperature inside the data centre. The outcome shows a desirable range of design input parameters for a data centre. Highlights Response surface model is trained using high fidelity CFD simulation data Radial basis function is found to show superior advantages in constructing response surface Rapid thermal profile reconstruction for data centre using response surface method is illustrated CFD-based response surface method for data centre optimization process is investigated","PeriodicalId":46184,"journal":{"name":"Advances in Building Energy Research","volume":"14 1","pages":"471 - 493"},"PeriodicalIF":2.0,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/17512549.2019.1622154","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47932892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1080/17512549.2019.1607776
Chong Wang, S. Yoo, Kazuhide Ito
ABSTRACT The prediction of the physiological response of the human body to the thermal environment is essential for healthy and comfortable indoor environmental design; hence, various rational thermoregulation models for estimating skin surface temperature have been developed based on the physics of heat and mass transfer between the human body and indoor environment, and on cybernetic models of the thermoregulatory system. Most of these models calculate the respiratory heat loss through the function of the pulmonary ventilation as well as the difference in water content between expiratory and inspiratory air, which describes a steady respiration process with a constant flow rate and fixed values of inspired/expired vapour pressure. In this study, a coupling numerical model combined with a thermoregulation model and a computer simulated person (CSP) with respiratory tract model that can be integrated with computational fluid dynamics has been developed. The coupling thermoregulation model used here are the multi-node model proposed by Stolwijk et al. and two-node model of Gagge, respectively. Based on this CSP with the thermoregulation model, a coupling analysis method combining the thermoregulation model and the model of dynamic heat and mass transfer/exchange in the respiratory tract is developed. This is followed by a discussion of the skin surface temperature predictions of the proposed model compared with those of the model using the traditional respiratory heat loss calculation method.
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