Pub Date : 2024-04-09DOI: 10.1177/1420326x241244525
Hangming Zhang, Ling Zhang, Yue Zheng, Zhongbing Liu
Improving the thermal performance of windows is important for building energy efficiency. Filling windows with variable transparency shape-stabilized phase change materials (VTSS-PCM) improves the thermal inertia of windows while avoiding the leakage of PCM. In this paper, a new type of VTSS-PCM window was proposed, tested, simulated and optimized in hot summer and cold winter climate zone. A numerical model of the VTSS-PCM window was built, and the model was validated using experimental tests. On this basis, three key parameters of VTSS-PCM were investigated and optimized. Finally, the energy and economic performance of the optimized VTSS-PCM window were compared with a typical hollow glass window. The results showed that the total annual unfavourable heat transfer (TAHT) and the annual investment cost (AIC) of the VTSS-PCM window obtained from the optimization were 118.16 kWh/m2 and 8.53 CNY/m2, respectively. Compared with the hollow glass window, the VTSS-PCM window reduced the TAHT by 30.14% and the total annual cost by 28.39%. The VTSS-PCM window produced a better development potential in terms of energy performance and economic performance. This study provided a reference for the application of the VTSS-PCM window in hot summer and cold winter regions of China.
{"title":"Energy and economic performance optimization of a window with variable transparency shape-stabilized PCM in hot summer and cold winter climate zone","authors":"Hangming Zhang, Ling Zhang, Yue Zheng, Zhongbing Liu","doi":"10.1177/1420326x241244525","DOIUrl":"https://doi.org/10.1177/1420326x241244525","url":null,"abstract":"Improving the thermal performance of windows is important for building energy efficiency. Filling windows with variable transparency shape-stabilized phase change materials (VTSS-PCM) improves the thermal inertia of windows while avoiding the leakage of PCM. In this paper, a new type of VTSS-PCM window was proposed, tested, simulated and optimized in hot summer and cold winter climate zone. A numerical model of the VTSS-PCM window was built, and the model was validated using experimental tests. On this basis, three key parameters of VTSS-PCM were investigated and optimized. Finally, the energy and economic performance of the optimized VTSS-PCM window were compared with a typical hollow glass window. The results showed that the total annual unfavourable heat transfer (TAHT) and the annual investment cost (AIC) of the VTSS-PCM window obtained from the optimization were 118.16 kWh/m<jats:sup>2</jats:sup> and 8.53 CNY/m<jats:sup>2</jats:sup>, respectively. Compared with the hollow glass window, the VTSS-PCM window reduced the TAHT by 30.14% and the total annual cost by 28.39%. The VTSS-PCM window produced a better development potential in terms of energy performance and economic performance. This study provided a reference for the application of the VTSS-PCM window in hot summer and cold winter regions of China.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140585462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1177/1420326x241242728
Zihe Gao, Jiajun Cai, Lin Jiang, Rhoda Afriyie Mensah, Chuangang Fan
In high-altitude tunnels, due to the ambient pressure and density of air being different from those under normal pressure, the convection and heat radiation in tunnels are also different when fires occur. As a result, the smoke exhaust capacity varies under different pressures. This work aimed to numerically explore the impact of ambient pressure on the smoke exhaust efficiency at high-altitude shallow tunnels with natural ventilation by shaft. The numerical results demonstrated that the smoke exhaust capacity is enhanced with increasing ambient pressure. This is because of the increase in the air entrainment coefficient and air density, and it causes plug-holing more easily to occur under higher ambient pressures. Once the plug-holing has taken place, the fresh air can be directly exhausted through the shaft, which results in a poor smoke exhaust capacity. By accounting for the factors of the smoke layer thickness, ambient pressure, the exhausted smoke temperature and heat release rate, the Richardson number was introduced as the criterion for determining whether plug-holing occurs. As ambient pressure was increased, the critical Richardson number for plug-holing was observed to decrease, a finding supported by existing research.
{"title":"Investigation on the natural smoke exhaust performance by vertical shaft in tunnel fires under different ambient pressures","authors":"Zihe Gao, Jiajun Cai, Lin Jiang, Rhoda Afriyie Mensah, Chuangang Fan","doi":"10.1177/1420326x241242728","DOIUrl":"https://doi.org/10.1177/1420326x241242728","url":null,"abstract":"In high-altitude tunnels, due to the ambient pressure and density of air being different from those under normal pressure, the convection and heat radiation in tunnels are also different when fires occur. As a result, the smoke exhaust capacity varies under different pressures. This work aimed to numerically explore the impact of ambient pressure on the smoke exhaust efficiency at high-altitude shallow tunnels with natural ventilation by shaft. The numerical results demonstrated that the smoke exhaust capacity is enhanced with increasing ambient pressure. This is because of the increase in the air entrainment coefficient and air density, and it causes plug-holing more easily to occur under higher ambient pressures. Once the plug-holing has taken place, the fresh air can be directly exhausted through the shaft, which results in a poor smoke exhaust capacity. By accounting for the factors of the smoke layer thickness, ambient pressure, the exhausted smoke temperature and heat release rate, the Richardson number was introduced as the criterion for determining whether plug-holing occurs. As ambient pressure was increased, the critical Richardson number for plug-holing was observed to decrease, a finding supported by existing research.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140585511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-06DOI: 10.1177/1420326x241244724
Hüseyin Ögçe, Meltem Erdem Kaya
The relationship between urban heat island (UHI) and land use/land cover (LULC), and local climate zone (LCZ) is apparent and takes rising attention in the current literature. This study aimed to investigate the relationship between meteorological data collected from 30 stations between 2016 and 2022 and Istanbul’s LULCs and LCZs. Several notable findings were uncovered, providing light on the UHI phenomenon and its consequences for the city’s characteristics. The stations in urban areas (typology A) had higher temperatures than stations in rural/suburban (typology B) and forested landscape (typology C). Those yearly values were ∼1°C for monthly mean temperatures and ∼1.5°C for monthly minimum temperatures. Moreover, urban areas possessed +4 and +2 hot days (35°C and above) for typologies B and C, respectively. Another remarkable result was that stations situated close to water surfaces exhibited a lower tendency to exceed temperatures of 35°C. Furthermore, built-type LCZs wind velocity achieved a lower value than land cover type, and humidity in typology A was 5% and 10% less than the typologies B and C, respectively. Consequently, the southern part of Istanbul emerged as the most vulnerable location to the UHI phenomena, suffering greater temperatures.
城市热岛(UHI)与土地利用/土地覆盖(LULC)和当地气候区(LCZ)之间的关系显而易见,并在当前文献中日益受到关注。本研究旨在调查 2016 年至 2022 年期间从 30 个站点收集的气象数据与伊斯坦布尔 LULC 和 LCZ 之间的关系。研究发现了几个值得注意的问题,揭示了超高寒现象及其对城市特征的影响。城市地区(类型 A)的站点温度高于农村/郊区(类型 B)和森林景观(类型 C)的站点。月平均气温的年平均值为 1°C,月最低气温的年平均值为 1.5°C。此外,在类型 B 和类型 C 中,城市地区分别拥有 +4 和 +2 个高温日(35°C 及以上)。另一个值得注意的结果是,靠近水面的站点气温超过 35℃的趋势较低。此外,建筑类型低纬度区的风速值低于土地覆被类型,类型 A 的湿度分别比类型 B 和类型 C 低 5%和 10%。因此,伊斯坦布尔南部地区最容易受到 UHI 现象的影响,温度更高。
{"title":"Urban heat island phenomenon in Istanbul: A comprehensive analysis of land use/land cover and local climate zone effect","authors":"Hüseyin Ögçe, Meltem Erdem Kaya","doi":"10.1177/1420326x241244724","DOIUrl":"https://doi.org/10.1177/1420326x241244724","url":null,"abstract":"The relationship between urban heat island (UHI) and land use/land cover (LULC), and local climate zone (LCZ) is apparent and takes rising attention in the current literature. This study aimed to investigate the relationship between meteorological data collected from 30 stations between 2016 and 2022 and Istanbul’s LULCs and LCZs. Several notable findings were uncovered, providing light on the UHI phenomenon and its consequences for the city’s characteristics. The stations in urban areas (typology A) had higher temperatures than stations in rural/suburban (typology B) and forested landscape (typology C). Those yearly values were ∼1°C for monthly mean temperatures and ∼1.5°C for monthly minimum temperatures. Moreover, urban areas possessed +4 and +2 hot days (35°C and above) for typologies B and C, respectively. Another remarkable result was that stations situated close to water surfaces exhibited a lower tendency to exceed temperatures of 35°C. Furthermore, built-type LCZs wind velocity achieved a lower value than land cover type, and humidity in typology A was 5% and 10% less than the typologies B and C, respectively. Consequently, the southern part of Istanbul emerged as the most vulnerable location to the UHI phenomena, suffering greater temperatures.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140585871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-03DOI: 10.1177/1420326x241244459
Zambri Harun, Nevzat Akkurt, Yu King Khor, Ashraf A Abbas, Eslam Reda Lotfy
The garden-city model, characterised by sprawling urban expansion and extensive open spaces, features green and water surfaces alongside substantial road networks, large parking lots and unshaded lands. This diverse landscape contributes to uneven air temperature distribution within the city. Our study investigated urban heat island (UHI) patterns in various urban environments within Putrajaya, focusing on rural, business, residential and near-water areas. Atmospheric data were collected over a year. Putrajaya exhibits two distinct UHI patterns: cool-day-hot-night in residential zones and hot-noon-temperate-elsewhere in impermeable areas. Business areas display alternating patterns based on seasonal climatic conditions and anthropogenic factors. The efficacy of artificial water bodies as a UHI countermeasure in garden cities depends on the size of the water body and the nature of the surrounding land cover. Shaded and green areas exhibit UHI intensities limited to 3°C, while impermeable areas, regardless of proximity to water surfaces, experience UHI up to 6°C. Overall, the garden-city model tends to restrict UHI variations within −1 to 3°C compared to −2 to 4°C in nearby Kuala Lumpur.
{"title":"Urban heat island patterns in garden cities: Putrajaya as a case study","authors":"Zambri Harun, Nevzat Akkurt, Yu King Khor, Ashraf A Abbas, Eslam Reda Lotfy","doi":"10.1177/1420326x241244459","DOIUrl":"https://doi.org/10.1177/1420326x241244459","url":null,"abstract":"The garden-city model, characterised by sprawling urban expansion and extensive open spaces, features green and water surfaces alongside substantial road networks, large parking lots and unshaded lands. This diverse landscape contributes to uneven air temperature distribution within the city. Our study investigated urban heat island (UHI) patterns in various urban environments within Putrajaya, focusing on rural, business, residential and near-water areas. Atmospheric data were collected over a year. Putrajaya exhibits two distinct UHI patterns: cool-day-hot-night in residential zones and hot-noon-temperate-elsewhere in impermeable areas. Business areas display alternating patterns based on seasonal climatic conditions and anthropogenic factors. The efficacy of artificial water bodies as a UHI countermeasure in garden cities depends on the size of the water body and the nature of the surrounding land cover. Shaded and green areas exhibit UHI intensities limited to 3°C, while impermeable areas, regardless of proximity to water surfaces, experience UHI up to 6°C. Overall, the garden-city model tends to restrict UHI variations within −1 to 3°C compared to −2 to 4°C in nearby Kuala Lumpur.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140585460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-01DOI: 10.1177/1420326x241242192
Hui Li, Jianfeng Tang, Chuck Wah Francis Yu, Chunwen Xu
{"title":"Utilization of biogas technology to supply energy for urban buildings and rural households: Benefits and potential risks","authors":"Hui Li, Jianfeng Tang, Chuck Wah Francis Yu, Chunwen Xu","doi":"10.1177/1420326x241242192","DOIUrl":"https://doi.org/10.1177/1420326x241242192","url":null,"abstract":"","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140585657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-29DOI: 10.1177/1420326x241243003
Ahmet Dogan, Nurullah Kayaci, Hakan Demir
This study investigated the impact of two types of internal blinds on the indoor thermal environment of a highly glazed office room in Istanbul during summer. The research examined four configurations: (i) no blinds, (ii) roller blinds, (iii) layered roller blinds in night mode and (iv) layered roller blinds in day mode. Measurements of air velocity, average radiation temperature, air temperature and relative humidity were conducted to assess thermal comfort. The findings revealed that internal blinds significantly influence thermal comfort in radiantly cooled office spaces during summer. Without blinds, the indoor environment only met ISO 7730 comfort category C, with average predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) values of 0.6 and 12.5%, respectively. However, with internal blinds, comfort categories A and B were achieved, resulting in improved thermal comfort levels, with average PMV and PPD values ranging from 0.2 to 0.3 and 6% to 7.5%, respectively. Roller blinds, in particular, proved highly effective in enhancing thermal comfort and reducing mean radiant and indoor air temperatures in highly glazed radiant cooling offices. This demonstrated their energy-efficient potential for improving indoor thermal comfort.
这项研究调查了两种类型的内部百叶帘对伊斯坦布尔一间高玻璃办公室夏季室内热环境的影响。研究考察了四种配置:(i) 无百叶帘;(ii) 卷帘;(iii) 夜间模式下的分层卷帘;(iv) 白天模式下的分层卷帘。通过测量空气流速、平均辐射温度、空气温度和相对湿度来评估热舒适度。研究结果表明,内部百叶帘对夏季辐射冷却办公空间的热舒适度有显著影响。在没有百叶帘的情况下,室内环境仅符合 ISO 7730 舒适度 C 类标准,平均预测平均投票(PMV)和预测不满意百分比(PPD)值分别为 0.6 和 12.5%。然而,使用内部百叶帘后,舒适度达到了 A 级和 B 级,从而提高了热舒适度,平均 PMV 和 PPD 值分别为 0.2 至 0.3 和 6% 至 7.5%。在高玻璃辐射冷却办公室中,卷帘在提高热舒适度、降低平均辐射温度和室内空气温度方面尤其有效。这表明卷帘在改善室内热舒适度方面具有节能潜力。
{"title":"The effect of internal blinds on thermal comfort: An experimental analysis in an office room with radiant panels","authors":"Ahmet Dogan, Nurullah Kayaci, Hakan Demir","doi":"10.1177/1420326x241243003","DOIUrl":"https://doi.org/10.1177/1420326x241243003","url":null,"abstract":"This study investigated the impact of two types of internal blinds on the indoor thermal environment of a highly glazed office room in Istanbul during summer. The research examined four configurations: (i) no blinds, (ii) roller blinds, (iii) layered roller blinds in night mode and (iv) layered roller blinds in day mode. Measurements of air velocity, average radiation temperature, air temperature and relative humidity were conducted to assess thermal comfort. The findings revealed that internal blinds significantly influence thermal comfort in radiantly cooled office spaces during summer. Without blinds, the indoor environment only met ISO 7730 comfort category C, with average predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD) values of 0.6 and 12.5%, respectively. However, with internal blinds, comfort categories A and B were achieved, resulting in improved thermal comfort levels, with average PMV and PPD values ranging from 0.2 to 0.3 and 6% to 7.5%, respectively. Roller blinds, in particular, proved highly effective in enhancing thermal comfort and reducing mean radiant and indoor air temperatures in highly glazed radiant cooling offices. This demonstrated their energy-efficient potential for improving indoor thermal comfort.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140368088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-22DOI: 10.1177/1420326x241241530
María L de la Hoz-Torres, Antonio J Aguilar, María Dolores Martínez-Aires, Diego P Ruiz
The assessment of indoor environmental conditions of educational buildings is not only essential to ensure the correct performance of heating, cooling and ventilation systems but it is also fundamental to guarantee a suitable environment. This study aims to analyse the thermal comfort of students in teaching–learning spaces in university buildings with natural ventilation. A field measurement campaign and a questionnaire survey were carried out from September 2021 to June 2022 in educational buildings in southern Spain. The collected data were analysed and the neutral temperature in each season was obtained, based on the thermal sensation votes of 1966. The neutral temperatures found in this study were 23.5°C, 23.1°C, 23.3°C and 23.9°C, for autumn, winter, spring and summer, respectively. The ranges obtained for 90% acceptability in the winter season (21.1°C–25.1°C) provided lower temperature limits than the ranges obtained in the summer months (22.6°C–25.3°C). The highest values for clothing insulation were found in the autumn (0.90 clo) and winter (0.75 clo) seasons, compared to the spring (0.5 clo) and summer (0.4 clo) seasons. An adaptive thermal comfort model was applied. These findings could be used to improve thermal comfort and to optimise energy consumption according to the students’ actual thermal perception.
{"title":"Seasonal field study on thermal comfort in university classrooms in Mediterranean climate","authors":"María L de la Hoz-Torres, Antonio J Aguilar, María Dolores Martínez-Aires, Diego P Ruiz","doi":"10.1177/1420326x241241530","DOIUrl":"https://doi.org/10.1177/1420326x241241530","url":null,"abstract":"The assessment of indoor environmental conditions of educational buildings is not only essential to ensure the correct performance of heating, cooling and ventilation systems but it is also fundamental to guarantee a suitable environment. This study aims to analyse the thermal comfort of students in teaching–learning spaces in university buildings with natural ventilation. A field measurement campaign and a questionnaire survey were carried out from September 2021 to June 2022 in educational buildings in southern Spain. The collected data were analysed and the neutral temperature in each season was obtained, based on the thermal sensation votes of 1966. The neutral temperatures found in this study were 23.5°C, 23.1°C, 23.3°C and 23.9°C, for autumn, winter, spring and summer, respectively. The ranges obtained for 90% acceptability in the winter season (21.1°C–25.1°C) provided lower temperature limits than the ranges obtained in the summer months (22.6°C–25.3°C). The highest values for clothing insulation were found in the autumn (0.90 clo) and winter (0.75 clo) seasons, compared to the spring (0.5 clo) and summer (0.4 clo) seasons. An adaptive thermal comfort model was applied. These findings could be used to improve thermal comfort and to optimise energy consumption according to the students’ actual thermal perception.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140205296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-20DOI: 10.1177/1420326x241240107
Zhu Chang, Haiguo Yin, Yuekun Han, Linfeng Liang
The prevalence of small-scale structures, such as sentry buildings, has become widespread, with many of these buildings exposed to the outdoor environment and exhibiting suboptimal thermal insulation in their envelopes. Through a comprehensive study of outdoor disturbances, the most unfavourable envelope was identified. In light of this finding, we have designed static air layer sentry buildings (SAL-SB) and dynamic air layer sentry buildings (DAL-SB). The study conducted experiments and numerical simulations to evaluate the impact of air layer thickness, vent opening forms, and inlet velocities on the thermal insulation of sentry buildings. The results showed that both the SAL and DAL effectively improved thermal insulation, and a thickness of 25 cm has been found to offer the best thermal insulation. However, considering the balance between thermal insulation and cost-effectiveness, a thickness of 15 cm is recommended. Additionally, for DAL, an inlet velocity of 3 m/s is the threshold for switching the heat transfer direction on the roof. These findings provide novel insights into enhancing the thermal environment.
小型建筑(如哨所建筑)已成为一种普遍现象,其中许多建筑都暴露在室外环境中,其围护结构的隔热性能也不尽人意。通过对室外干扰的全面研究,我们确定了最不利的围护结构。根据这一发现,我们设计了静态空气层哨兵建筑(SAL-SB)和动态空气层哨兵建筑(DAL-SB)。研究通过实验和数值模拟,评估了空气层厚度、通风口开口形式和入口速度对哨兵建筑隔热性能的影响。结果表明,SAL 和 DAL 都能有效提高隔热性能,其中 25 厘米的厚度具有最佳隔热性能。不过,考虑到隔热性和成本效益之间的平衡,建议厚度为 15 厘米。此外,对于 DAL 来说,3 米/秒的入口速度是切换屋顶传热方向的临界值。这些发现为改善热环境提供了新的见解。
{"title":"Design and evaluation of thermal insulation of air layer for sentry building envelopes","authors":"Zhu Chang, Haiguo Yin, Yuekun Han, Linfeng Liang","doi":"10.1177/1420326x241240107","DOIUrl":"https://doi.org/10.1177/1420326x241240107","url":null,"abstract":"The prevalence of small-scale structures, such as sentry buildings, has become widespread, with many of these buildings exposed to the outdoor environment and exhibiting suboptimal thermal insulation in their envelopes. Through a comprehensive study of outdoor disturbances, the most unfavourable envelope was identified. In light of this finding, we have designed static air layer sentry buildings (SAL-SB) and dynamic air layer sentry buildings (DAL-SB). The study conducted experiments and numerical simulations to evaluate the impact of air layer thickness, vent opening forms, and inlet velocities on the thermal insulation of sentry buildings. The results showed that both the SAL and DAL effectively improved thermal insulation, and a thickness of 25 cm has been found to offer the best thermal insulation. However, considering the balance between thermal insulation and cost-effectiveness, a thickness of 15 cm is recommended. Additionally, for DAL, an inlet velocity of 3 m/s is the threshold for switching the heat transfer direction on the roof. These findings provide novel insights into enhancing the thermal environment.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140196301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-19DOI: 10.1177/1420326x241240112
Kun Han, Jiawei Zhuang, Li’an Zhang, Yongfa Diao
The high-temperature particles produced by air gouging processes are common pollutants in cleaning workshops, which could endanger workers’ health. In this research, a two-way coupled Eulerian-Lagrangian method based on discrete phase modelling (DPM) was used to investigate the transport characteristics of high-temperature particles generated from air gouging processes. The particle group in the movement was divided into core zone and boundary zone, and the kinetic mechanism of particles in different zones was analysed. The results show particles in the boundary zone are more susceptible to the vortex entrainment effect than particles in the core zone, and some particles could be moved from the vortex diffusion zone to the vortex recirculation zone. The smaller the particle size, the better the followability to the hot airflow. The slower the temperature decay of particles, the more significant the thermophoresis effect, which could enhance the diffusion behaviour of the small particles. By analysing the average residence time of particles in the breathing zone, the influence of different factors on the average vertical diffusion height [Formula: see text] of particles is summarized, and a nonlinear regression prediction model of [Formula: see text] is established. The results can contribute to health risk assessment and industrial ventilation design.
{"title":"A numerical research on transient transport of high-temperature particles associated with air gouging process","authors":"Kun Han, Jiawei Zhuang, Li’an Zhang, Yongfa Diao","doi":"10.1177/1420326x241240112","DOIUrl":"https://doi.org/10.1177/1420326x241240112","url":null,"abstract":"The high-temperature particles produced by air gouging processes are common pollutants in cleaning workshops, which could endanger workers’ health. In this research, a two-way coupled Eulerian-Lagrangian method based on discrete phase modelling (DPM) was used to investigate the transport characteristics of high-temperature particles generated from air gouging processes. The particle group in the movement was divided into core zone and boundary zone, and the kinetic mechanism of particles in different zones was analysed. The results show particles in the boundary zone are more susceptible to the vortex entrainment effect than particles in the core zone, and some particles could be moved from the vortex diffusion zone to the vortex recirculation zone. The smaller the particle size, the better the followability to the hot airflow. The slower the temperature decay of particles, the more significant the thermophoresis effect, which could enhance the diffusion behaviour of the small particles. By analysing the average residence time of particles in the breathing zone, the influence of different factors on the average vertical diffusion height [Formula: see text] of particles is summarized, and a nonlinear regression prediction model of [Formula: see text] is established. The results can contribute to health risk assessment and industrial ventilation design.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140167310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-19DOI: 10.1177/1420326x241240438
Dawei Wang, Panxiu Wang, A. Ditta, Gang Chen
The external building walls are significant in mitigating adverse weather conditions. Current research on the thermal insulation of exterior walls often overlooks crucial factors such as human comfort, seasonal changes and environmental dynamics. This study introduced a performance evaluation approach for external walls that considered the human thermal zone, annual air temperature and solar radiation. Taking Nanjing City as a case study, the thermal insulation performance of five distinct types of building exterior walls was investigated. The findings highlight the impact of various insulated wall systems on thermal insulation. While different insulated walls exhibited significant variations in effectiveness during extreme weather episodes, these variations were minor over the course of the year. Analysis revealed a spectrum of performance for insulated exterior walls, ranging from excellent to poor: Outer Insulated Wall > Inside Insulated Wall = Sandwich Insulated Wall = Self-Insulated Wall > Mortar-Insulated Wall. The disparity in thermal insulation performance amongst four wall types was minimal, with the mortar-insulated wall demonstrating the lowest performance. The highest temperature recorded for the mortar-insulated wall surpassed 32.2°C over 68 days. This research contributes insights into the nuanced performance of various insulated walls, paving the way for decision-making in climate resilience strategies.
{"title":"Optimizing thermal insulation in building facades: An examination of human-environment dynamics in Nanjing city, Eastern Asia","authors":"Dawei Wang, Panxiu Wang, A. Ditta, Gang Chen","doi":"10.1177/1420326x241240438","DOIUrl":"https://doi.org/10.1177/1420326x241240438","url":null,"abstract":"The external building walls are significant in mitigating adverse weather conditions. Current research on the thermal insulation of exterior walls often overlooks crucial factors such as human comfort, seasonal changes and environmental dynamics. This study introduced a performance evaluation approach for external walls that considered the human thermal zone, annual air temperature and solar radiation. Taking Nanjing City as a case study, the thermal insulation performance of five distinct types of building exterior walls was investigated. The findings highlight the impact of various insulated wall systems on thermal insulation. While different insulated walls exhibited significant variations in effectiveness during extreme weather episodes, these variations were minor over the course of the year. Analysis revealed a spectrum of performance for insulated exterior walls, ranging from excellent to poor: Outer Insulated Wall > Inside Insulated Wall = Sandwich Insulated Wall = Self-Insulated Wall > Mortar-Insulated Wall. The disparity in thermal insulation performance amongst four wall types was minimal, with the mortar-insulated wall demonstrating the lowest performance. The highest temperature recorded for the mortar-insulated wall surpassed 32.2°C over 68 days. This research contributes insights into the nuanced performance of various insulated walls, paving the way for decision-making in climate resilience strategies.","PeriodicalId":13578,"journal":{"name":"Indoor and Built Environment","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140167241","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}