Pub Date : 2020-12-07DOI: 10.1080/14733315.2020.1853881
C. Su, ShiuanCheng Wang, YaoHan Chen, CheYi Wu
Abstract In some countries, test standards have been adopted which measure the effectiveness of smoke exhaust systems in clearing out heat and smoke produced separately. However, because these standards provide no quantitative provisions for dealing with the amount of visual smoke, there is an unclear correlation between the amount of smoke generated and the fire load. This paper applied the homogeneity concept of using a smoke collection box to examine the smoke generation rate of a smoke generator using CO2 as the driving gas. To avoid using the previous visual method of judging the rates, this research used measurement equipment to conduct a scientific analysis. Thus, the results were more objective. The equipment used included a Closed-Circuit Television (CCTV) Camera, a thermocouple, a traditional P-type smoke detector, a digital R-type smoke detector, and light attenuation measurement equipment. Under release pressures of 40, 60 and 80 psi, a 15% smoke density required smoke generation at 6.50, 8.42 and 10.46 m3/s, respectively. Achieving a homogeneous distribution of smoke within the space was accomplished. The data obtained in the test could be used not only to judge the efficiency of a smoke exhaust system but also provide adjustment information for a smoke exhaust system.
{"title":"Measurement of smoke generation rate using a full-scale hot smoke test for building smoke exhaust systems","authors":"C. Su, ShiuanCheng Wang, YaoHan Chen, CheYi Wu","doi":"10.1080/14733315.2020.1853881","DOIUrl":"https://doi.org/10.1080/14733315.2020.1853881","url":null,"abstract":"Abstract In some countries, test standards have been adopted which measure the effectiveness of smoke exhaust systems in clearing out heat and smoke produced separately. However, because these standards provide no quantitative provisions for dealing with the amount of visual smoke, there is an unclear correlation between the amount of smoke generated and the fire load. This paper applied the homogeneity concept of using a smoke collection box to examine the smoke generation rate of a smoke generator using CO2 as the driving gas. To avoid using the previous visual method of judging the rates, this research used measurement equipment to conduct a scientific analysis. Thus, the results were more objective. The equipment used included a Closed-Circuit Television (CCTV) Camera, a thermocouple, a traditional P-type smoke detector, a digital R-type smoke detector, and light attenuation measurement equipment. Under release pressures of 40, 60 and 80 psi, a 15% smoke density required smoke generation at 6.50, 8.42 and 10.46 m3/s, respectively. Achieving a homogeneous distribution of smoke within the space was accomplished. The data obtained in the test could be used not only to judge the efficiency of a smoke exhaust system but also provide adjustment information for a smoke exhaust system.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"26 1","pages":"105 - 121"},"PeriodicalIF":1.5,"publicationDate":"2020-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83738495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-11-18DOI: 10.1080/14733315.2020.1833518
A. D. Istiadji, P. Satwiko, Y. P. Suhodo, N. Sekarlangit, A. Prasetya, Israni Silvia
Abstract This paper reports on the development of an organic air cleaner (OAC), an interior architectural element that optimises plants’ CO2 absorption in nonventilated air-conditioned rooms. Sansevieria trifasciata, Dracaena sanderiana, Scindapsus aureus and Syngonium podophyllum were explored. Two methods were adopted: the plants’ CO2 uptake was measured, and the results were used for the computer simulation inputs. An OAC works automatically by exposing the plants to indoor or outdoor air when the plants are in, consecutively, CO2 absorbtion or emission phase. Computer simulations found that the most efficient placement for OACs to absorb CO2 is to put them far from ACs.
{"title":"The development of an organic air cleaner (OAC) to reduce CO2 level of air-conditioned rooms without fresh air supply","authors":"A. D. Istiadji, P. Satwiko, Y. P. Suhodo, N. Sekarlangit, A. Prasetya, Israni Silvia","doi":"10.1080/14733315.2020.1833518","DOIUrl":"https://doi.org/10.1080/14733315.2020.1833518","url":null,"abstract":"Abstract This paper reports on the development of an organic air cleaner (OAC), an interior architectural element that optimises plants’ CO2 absorption in nonventilated air-conditioned rooms. Sansevieria trifasciata, Dracaena sanderiana, Scindapsus aureus and Syngonium podophyllum were explored. Two methods were adopted: the plants’ CO2 uptake was measured, and the results were used for the computer simulation inputs. An OAC works automatically by exposing the plants to indoor or outdoor air when the plants are in, consecutively, CO2 absorbtion or emission phase. Computer simulations found that the most efficient placement for OACs to absorb CO2 is to put them far from ACs.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"9 1","pages":"195 - 212"},"PeriodicalIF":1.5,"publicationDate":"2020-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82055061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-11-03DOI: 10.1080/14733315.2020.1839243
Weixin Zhao, Sami Lestinen, S. Kilpeläinen, R. Kosonen
Abstract In this study, indoor air quality and thermal conditions were studied under laboratory conditions with the heat load that was located symmetrically or asymmetrically in the room. Diffuse ceiling ventilation (DCV) was adopted to provide cooling and outdoor air to the room. CO2 concentration, room air temperature and air speed were measured in the test chamber. This study gives insight of both thermal comfort and indoor air quality with different heat load levels and load distribution. The results show that the strength, distribution and the type of heat load have a significant influence on air distribution and thermal comfort. In all cases, the performance of the diffused ceiling ventilation was like fully mixed ventilation. The mean air temperature and speed increase with the heat load, as a result, also draught rate increases, which meant the heat load distribution has effect on local thermal discomfort.
{"title":"Comparison of the effects of symmetric and asymmetric heat load on indoor air quality and local thermal discomfort with diffuse ceiling ventilation","authors":"Weixin Zhao, Sami Lestinen, S. Kilpeläinen, R. Kosonen","doi":"10.1080/14733315.2020.1839243","DOIUrl":"https://doi.org/10.1080/14733315.2020.1839243","url":null,"abstract":"Abstract In this study, indoor air quality and thermal conditions were studied under laboratory conditions with the heat load that was located symmetrically or asymmetrically in the room. Diffuse ceiling ventilation (DCV) was adopted to provide cooling and outdoor air to the room. CO2 concentration, room air temperature and air speed were measured in the test chamber. This study gives insight of both thermal comfort and indoor air quality with different heat load levels and load distribution. The results show that the strength, distribution and the type of heat load have a significant influence on air distribution and thermal comfort. In all cases, the performance of the diffused ceiling ventilation was like fully mixed ventilation. The mean air temperature and speed increase with the heat load, as a result, also draught rate increases, which meant the heat load distribution has effect on local thermal discomfort.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"11 2","pages":"19 - 34"},"PeriodicalIF":1.5,"publicationDate":"2020-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/14733315.2020.1839243","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72417479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-10-01DOI: 10.1080/14733315.2019.1687178
Zhilei Wang, Xinxin Guo, Xuhai Pan, Li Zhu, Juan Yang, M. Hua, Juncheng Jiang
Abstract This study proposed a hybrid ventilation mode for underground subway depot with superstructures and described the construction of a calculation model for estimating the smoke-exhaust efficiency of ventilation systems in such buildings. The hybrid ventilation system consisted of natural ventilation, a flow deflector, and mechanical fans. The smoke-layer height, smoke temperature, gas-flow routes, and velocity distribution under the ceiling were recorded, and the smoke-exhaust efficiencies of the three ventilation modes were calculated and compared. The results revealed a lower ceiling temperature in hybrid ventilation than in mechanical ventilation or natural ventilation systems, with no smoke accumulation in the bottom layer or interlayer. Therefore, the thickness and stability of the smoke layer was determined to be more desirable in hybrid ventilation than in the other two ventilation systems. Gas-flow routes demonstrated that air from outside flowed in through the side window along the ceiling of the bottom layer to the exhaust fan. The dispersion of hot smoke was thus impeded, and smoke was entrained into the fan. The smoke-exhaust efficiencies of hybrid ventilation and mechanical ventilation systems were similar, and both were higher than that of natural ventilation.
{"title":"Numerical simulation of hybrid ventilation for underground subway depot with superstructures","authors":"Zhilei Wang, Xinxin Guo, Xuhai Pan, Li Zhu, Juan Yang, M. Hua, Juncheng Jiang","doi":"10.1080/14733315.2019.1687178","DOIUrl":"https://doi.org/10.1080/14733315.2019.1687178","url":null,"abstract":"Abstract This study proposed a hybrid ventilation mode for underground subway depot with superstructures and described the construction of a calculation model for estimating the smoke-exhaust efficiency of ventilation systems in such buildings. The hybrid ventilation system consisted of natural ventilation, a flow deflector, and mechanical fans. The smoke-layer height, smoke temperature, gas-flow routes, and velocity distribution under the ceiling were recorded, and the smoke-exhaust efficiencies of the three ventilation modes were calculated and compared. The results revealed a lower ceiling temperature in hybrid ventilation than in mechanical ventilation or natural ventilation systems, with no smoke accumulation in the bottom layer or interlayer. Therefore, the thickness and stability of the smoke layer was determined to be more desirable in hybrid ventilation than in the other two ventilation systems. Gas-flow routes demonstrated that air from outside flowed in through the side window along the ceiling of the bottom layer to the exhaust fan. The dispersion of hot smoke was thus impeded, and smoke was entrained into the fan. The smoke-exhaust efficiencies of hybrid ventilation and mechanical ventilation systems were similar, and both were higher than that of natural ventilation.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"40 1","pages":"280 - 299"},"PeriodicalIF":1.5,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90375006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-10-01DOI: 10.1080/14733315.2019.1667558
N. Baker, G. Kelly, Paul D. O'Sullivan
Abstract The Grid Convergence Index () method requires at least three systematic mesh refinements, each requiring the numerical solution to be in the asymptotic range. When the observed order of accuracy differs from the formal order of accuracy, a lack of numerical precision exists which may result in erroneous conclusions. The aim of the work in this paper is to evaluate the effect the mesh resolution for structured hexahedral, unstructured hexahedral and tetrahedral mesh has on the observed order of accuracy and the accuracy of the numerical solution of the mean air flow velocity profile in indoor environments. The value was calculated based on the recommendation of the lower limit of the observed order of accuracy. For the structured hexahedral mesh, with successive grid refinements the observed order of accuracy converges close to the formal order of accuracy, while for the two other unstructured meshes it converges more gradually. The lowest value was obtained when the observed order of accuracy has reached its highest level of accuracy. In this study the turbulence model was adopted, and when the obtained numerical results were compared with another published numerical study, the comparison showed that the structured hexahedral mesh with turbulence model produced a similar result to that produced from unstructured hexahedral mesh using the turbulence model.
{"title":"A grid convergence index study of mesh style effect on the accuracy of the numerical results for an indoor airflow profile","authors":"N. Baker, G. Kelly, Paul D. O'Sullivan","doi":"10.1080/14733315.2019.1667558","DOIUrl":"https://doi.org/10.1080/14733315.2019.1667558","url":null,"abstract":"Abstract The Grid Convergence Index () method requires at least three systematic mesh refinements, each requiring the numerical solution to be in the asymptotic range. When the observed order of accuracy differs from the formal order of accuracy, a lack of numerical precision exists which may result in erroneous conclusions. The aim of the work in this paper is to evaluate the effect the mesh resolution for structured hexahedral, unstructured hexahedral and tetrahedral mesh has on the observed order of accuracy and the accuracy of the numerical solution of the mean air flow velocity profile in indoor environments. The value was calculated based on the recommendation of the lower limit of the observed order of accuracy. For the structured hexahedral mesh, with successive grid refinements the observed order of accuracy converges close to the formal order of accuracy, while for the two other unstructured meshes it converges more gradually. The lowest value was obtained when the observed order of accuracy has reached its highest level of accuracy. In this study the turbulence model was adopted, and when the obtained numerical results were compared with another published numerical study, the comparison showed that the structured hexahedral mesh with turbulence model produced a similar result to that produced from unstructured hexahedral mesh using the turbulence model.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"4 1","pages":"300 - 314"},"PeriodicalIF":1.5,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81315877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-10-01DOI: 10.1080/14733315.2019.1665784
Rania Elghamry, H. Hassan
Abstract In this paper, the impact of window parameters (shape, design, sizes, position and orientation) on the building thermal comfort (temperature, relative humidity and discomfort period), energy consumption (lighting loads, heating and cooling loads and total energy consumption) and cost, and environment effect (CO2 emissions) is analysed under hot semi-arid climate conditions. This study considers the effective window design parameters; window to wall area ratio (WWR), position on the wall, and orientation. An experimental setup is used to validate the numerical solution of the mathematical model by Design-Builder software. Results show that window at north has the minimum interior temperature, discomfort hours, cooling load, CO2 emissions, total energy consumption and energy cost, and maximum lighting, relative humidity and heating load and contrarily the window at south. Window characteristics haven’t great effect on the relative humidity. Increasing WWR increases the cooling load, interior temperature, energy consumption and cost and decreases lighting and heating loads. Window shape ratio (2-1) and middle position represent the lowest in the energy consumption contrarily ratio (1-3) and down position. Controlling, studied window parameters reduces annual cooling load by about 30%, lighting power, CO2 emissions, annual energy consumption and energy cost by about 39%, 22%, 24% and 21%, respectively.
{"title":"Impact of window parameters on the building envelope on the thermal comfort, energy consumption and cost and environment","authors":"Rania Elghamry, H. Hassan","doi":"10.1080/14733315.2019.1665784","DOIUrl":"https://doi.org/10.1080/14733315.2019.1665784","url":null,"abstract":"Abstract In this paper, the impact of window parameters (shape, design, sizes, position and orientation) on the building thermal comfort (temperature, relative humidity and discomfort period), energy consumption (lighting loads, heating and cooling loads and total energy consumption) and cost, and environment effect (CO2 emissions) is analysed under hot semi-arid climate conditions. This study considers the effective window design parameters; window to wall area ratio (WWR), position on the wall, and orientation. An experimental setup is used to validate the numerical solution of the mathematical model by Design-Builder software. Results show that window at north has the minimum interior temperature, discomfort hours, cooling load, CO2 emissions, total energy consumption and energy cost, and maximum lighting, relative humidity and heating load and contrarily the window at south. Window characteristics haven’t great effect on the relative humidity. Increasing WWR increases the cooling load, interior temperature, energy consumption and cost and decreases lighting and heating loads. Window shape ratio (2-1) and middle position represent the lowest in the energy consumption contrarily ratio (1-3) and down position. Controlling, studied window parameters reduces annual cooling load by about 30%, lighting power, CO2 emissions, annual energy consumption and energy cost by about 39%, 22%, 24% and 21%, respectively.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"3 2","pages":"233 - 259"},"PeriodicalIF":1.5,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/14733315.2019.1665784","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72453924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-10-01DOI: 10.1080/14733315.2019.1665861
Sam Bonser, B. Hughes, J. Calautit
Abstract The present study provides an analysis of existing literature encompassing the wind and thermal analysis of football stadia, and how both can be manipulated through the modification of roof geometry. It introduces the potential for cooling strategies to create an internal environment capable of hosting elite-level international football in a hot climate. The motivation for the study stems from an absence of existing literature focussing on thermal flow in hot conditions for stadia and the requirement to investigate the hosting capabilities of Qatar for the 2022 FIFA World Cup. Stadium design plays a crucial role in determining the success of the tournament not only through the month-long event, but also with the legacy it leaves afterwards. To carry out the analysis, Computational Fluid Dynamics (CFD) simulations were conducted in an effort to produce internal conditions that satisfy official FIFA guidelines on optimal playing conditions in terms of wind and temperature distribution. These are ran on a model validated against existing literature to ensure accuracy, but considering the potential for error between model generations. The conclusions drawn suggest that a downward-pitched, large-radius retractable roof subsidised by the introduction of a mechanical system to create a cooling strategy reduces the external temperature down to 23 °C, with wind velocities not exceeding 4 m/s. Reinforced by results, these desired playing conditions can be achieved by closing the roof to precondition the stadium before an event, with the roof then retracted to ensure compliance with FIFA guidelines. The results from the present study can be a component in achieving a sustained positive legacy for the upcoming FIFA World Cup.
{"title":"Investigation of the impact of roof configurations on the wind and thermal environment in football stadiums in hot climates","authors":"Sam Bonser, B. Hughes, J. Calautit","doi":"10.1080/14733315.2019.1665861","DOIUrl":"https://doi.org/10.1080/14733315.2019.1665861","url":null,"abstract":"Abstract The present study provides an analysis of existing literature encompassing the wind and thermal analysis of football stadia, and how both can be manipulated through the modification of roof geometry. It introduces the potential for cooling strategies to create an internal environment capable of hosting elite-level international football in a hot climate. The motivation for the study stems from an absence of existing literature focussing on thermal flow in hot conditions for stadia and the requirement to investigate the hosting capabilities of Qatar for the 2022 FIFA World Cup. Stadium design plays a crucial role in determining the success of the tournament not only through the month-long event, but also with the legacy it leaves afterwards. To carry out the analysis, Computational Fluid Dynamics (CFD) simulations were conducted in an effort to produce internal conditions that satisfy official FIFA guidelines on optimal playing conditions in terms of wind and temperature distribution. These are ran on a model validated against existing literature to ensure accuracy, but considering the potential for error between model generations. The conclusions drawn suggest that a downward-pitched, large-radius retractable roof subsidised by the introduction of a mechanical system to create a cooling strategy reduces the external temperature down to 23 °C, with wind velocities not exceeding 4 m/s. Reinforced by results, these desired playing conditions can be achieved by closing the roof to precondition the stadium before an event, with the roof then retracted to ensure compliance with FIFA guidelines. The results from the present study can be a component in achieving a sustained positive legacy for the upcoming FIFA World Cup.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"23 1","pages":"260 - 279"},"PeriodicalIF":1.5,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79252342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-09-23DOI: 10.1080/14733315.2020.1823071
Y. E. Cetin, M. Avci, O. Aydin
Abstract In this study, effect of air change rate (air change per hour – ACH) on indoor particle dispersion and deposition in a ventilated room is investigated. A reduced-scale model is designed to conduct experiments. Numerical predictions are performed by using the commercial software ANSYS Fluent 16.0. Four different values of the air change rate (1.73, 2.88, 5.76 and 7.68) and five different values of the particle diameter (0.181, 2.188, 4.42, 8.89 and 17.8 μm) are considered. Constant particle flow rate and proportional particle flow rate with inlet velocity cases are examined comparatively. Results show that, except from some inconsistencies for the largest particle diameter due to the accumulation and outlet opening location, the contaminant level decreases with increasing air change rate for a constant value of the particle flow rate while an opposite trend is observed for the proportional particle flow rate case.
{"title":"Effect of air change rate on particle dispersion from inlet opening under varying particle source strengths","authors":"Y. E. Cetin, M. Avci, O. Aydin","doi":"10.1080/14733315.2020.1823071","DOIUrl":"https://doi.org/10.1080/14733315.2020.1823071","url":null,"abstract":"Abstract In this study, effect of air change rate (air change per hour – ACH) on indoor particle dispersion and deposition in a ventilated room is investigated. A reduced-scale model is designed to conduct experiments. Numerical predictions are performed by using the commercial software ANSYS Fluent 16.0. Four different values of the air change rate (1.73, 2.88, 5.76 and 7.68) and five different values of the particle diameter (0.181, 2.188, 4.42, 8.89 and 17.8 μm) are considered. Constant particle flow rate and proportional particle flow rate with inlet velocity cases are examined comparatively. Results show that, except from some inconsistencies for the largest particle diameter due to the accumulation and outlet opening location, the contaminant level decreases with increasing air change rate for a constant value of the particle flow rate while an opposite trend is observed for the proportional particle flow rate case.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"138 1","pages":"177 - 194"},"PeriodicalIF":1.5,"publicationDate":"2020-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85995633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-09-17DOI: 10.1080/14733315.2020.1812223
Hasna Abid, Z. Driss
Abstract In an indoor environment, many factors may affect the airflow characteristics and thermal comfort. Hence, a lot of research has been carried out in order to investigate the impact of these factors. The purpose of this study is to determine the effect of supply area, with maintaining the same supply airflow rate, on the airflow characteristics and the indoor thermal comfort for a ventilated box prototype occupied by a thermal manikin. Understanding the behavior of the airflow in a mechanical ventilated box occupied by a thermal manikin is the main objective of this paper. Hence, numerical simulations were carried out using the software ANSYS FLUENT 17.0. According to the obtained results, the inlet velocity has a direct effect on the velocity fields, the temperature, the static pressure and the turbulence characteristics. In addition, the numerical results affirmed that the supply area has a direct impact on indoor thermal comfort.
{"title":"Computational study and experimental validation on the effect of inlet hole surface on airflow characteristics and thermal comfort in a box occupied by a thermal manikin","authors":"Hasna Abid, Z. Driss","doi":"10.1080/14733315.2020.1812223","DOIUrl":"https://doi.org/10.1080/14733315.2020.1812223","url":null,"abstract":"Abstract In an indoor environment, many factors may affect the airflow characteristics and thermal comfort. Hence, a lot of research has been carried out in order to investigate the impact of these factors. The purpose of this study is to determine the effect of supply area, with maintaining the same supply airflow rate, on the airflow characteristics and the indoor thermal comfort for a ventilated box prototype occupied by a thermal manikin. Understanding the behavior of the airflow in a mechanical ventilated box occupied by a thermal manikin is the main objective of this paper. Hence, numerical simulations were carried out using the software ANSYS FLUENT 17.0. According to the obtained results, the inlet velocity has a direct effect on the velocity fields, the temperature, the static pressure and the turbulence characteristics. In addition, the numerical results affirmed that the supply area has a direct impact on indoor thermal comfort.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"23 1","pages":"140 - 156"},"PeriodicalIF":1.5,"publicationDate":"2020-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80543639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 : 2020-09-15DOI: 10.1080/14733315.2020.1817284
Jipeng Wang, Yan Wang, Fan Wu, Peihong Wu, Juncheng Jiang
Abstract The fire protection design in a large-scale interchange station is always a great challenge. In this paper, a series of numerical simulations were conducted to investigate the performance of emergency ventilation modes for three potential multisource fire scenarios. The parameters that influence passengers’ evacuation were analyzed. The results demonstrated that unreasonable co-operation ventilation mode enhances the smoke propagation in other lines. The interaction of ventilation modes in different lines must be considered in practice. When the multisource fires occur on the same floor of both lines, the most effective scheme is to adopt the same ventilation mode in each line. When the multisource fires occur on different floors of both lines, it is difficult to maintain a balance of the exhaust capability in each line. The optimal ventilation modes were finally proposed for three fire scenarios based on the smoke discharge capability in the whole station.
{"title":"Study on emergency ventilation mode for multisource fires in a typical interchange subway station","authors":"Jipeng Wang, Yan Wang, Fan Wu, Peihong Wu, Juncheng Jiang","doi":"10.1080/14733315.2020.1817284","DOIUrl":"https://doi.org/10.1080/14733315.2020.1817284","url":null,"abstract":"Abstract The fire protection design in a large-scale interchange station is always a great challenge. In this paper, a series of numerical simulations were conducted to investigate the performance of emergency ventilation modes for three potential multisource fire scenarios. The parameters that influence passengers’ evacuation were analyzed. The results demonstrated that unreasonable co-operation ventilation mode enhances the smoke propagation in other lines. The interaction of ventilation modes in different lines must be considered in practice. When the multisource fires occur on the same floor of both lines, the most effective scheme is to adopt the same ventilation mode in each line. When the multisource fires occur on different floors of both lines, it is difficult to maintain a balance of the exhaust capability in each line. The optimal ventilation modes were finally proposed for three fire scenarios based on the smoke discharge capability in the whole station.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"42 1","pages":"157 - 176"},"PeriodicalIF":1.5,"publicationDate":"2020-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85676289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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