Pub Date : 2020-04-02DOI: 10.1080/14733315.2019.1592333
D. Krawczyk, M. Zukowski
Abstract One of important parameters of a room microclimate is carbon dioxide level that could be predicted using models presented in literature. In buildings with high heat gains from people, like classrooms, conference rooms or gyms, during estimation of the CO2 concentration it is strongly recommended to take into account changes of indoor air temperature. The article presents a mathematical model of the phenomena of heat transport in a room that includes heat transfer between the analysed room and surroundings, air exchange within the confines of natural ventilation and infiltration, heat gains from people and solar gains. The numerical solution draws upon an analogy between the mathematical description of the non-stationary fields of temperature and electrical potentials. A simulation of the indoor temperature changes was applied to the carbon dioxide concentration model formulated by Krawczyk, Rodero, Gładyszewska-Fiedoruk and Gajewski and a T-CO2 model was developed. Presented methodology and delivered application allows to estimate CO2 level changes in rooms in significantly more precise way than setting temperature at constant level.
{"title":"Experimental verification of the CO2 and temperature model","authors":"D. Krawczyk, M. Zukowski","doi":"10.1080/14733315.2019.1592333","DOIUrl":"https://doi.org/10.1080/14733315.2019.1592333","url":null,"abstract":"Abstract One of important parameters of a room microclimate is carbon dioxide level that could be predicted using models presented in literature. In buildings with high heat gains from people, like classrooms, conference rooms or gyms, during estimation of the CO2 concentration it is strongly recommended to take into account changes of indoor air temperature. The article presents a mathematical model of the phenomena of heat transport in a room that includes heat transfer between the analysed room and surroundings, air exchange within the confines of natural ventilation and infiltration, heat gains from people and solar gains. The numerical solution draws upon an analogy between the mathematical description of the non-stationary fields of temperature and electrical potentials. A simulation of the indoor temperature changes was applied to the carbon dioxide concentration model formulated by Krawczyk, Rodero, Gładyszewska-Fiedoruk and Gajewski and a T-CO2 model was developed. Presented methodology and delivered application allows to estimate CO2 level changes in rooms in significantly more precise way than setting temperature at constant level.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"1 1","pages":"127 - 140"},"PeriodicalIF":1.5,"publicationDate":"2020-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89684053","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 : 2020-04-02DOI: 10.1080/14733315.2019.1579485
P. Martínez, P. Martínez, V. Soto, J. Rodriguez, L. Bujedo
Abstract Current ventilation airflow rates imposed by building regulations eventually force HVAC systems to remove high latent loads. Dedicated outdoor air systems (DOASs) equipped with a desiccant wheel, are an alternative to conventional refrigeration equipment for humidity control in buildings. This paper studies the operation of a DOAS intended to remove the ventilation air and space latent load in different Spanish climates during the summer season. The model developed in TRNSYS was validated with experimental data using the root mean standard error (RMSE). Maximum RMSE of 0.94 °C and 0.472 g/kg were obtained for the temperatures and humidity ratios of the process and regeneration airflows. The RMSE for the compressor power input was of 52.2 W. The results obtained with the developed model showed that the DOAS exhibited better performance in humid climates with moderate temperatures (Bilbao and Barcelona). It was also found that its application in dry climates (Madrid) was not appropriate, and that a high outdoor temperature lowered the DOAS efficiency when comparing cities with similar latent loads (Bilbao and Sevilla) or when comparing residential and commercial schedules.
{"title":"Analysis of a DOAS operation in different Spanish climates using an experimentally validated TRNSYS model","authors":"P. Martínez, P. Martínez, V. Soto, J. Rodriguez, L. Bujedo","doi":"10.1080/14733315.2019.1579485","DOIUrl":"https://doi.org/10.1080/14733315.2019.1579485","url":null,"abstract":"Abstract Current ventilation airflow rates imposed by building regulations eventually force HVAC systems to remove high latent loads. Dedicated outdoor air systems (DOASs) equipped with a desiccant wheel, are an alternative to conventional refrigeration equipment for humidity control in buildings. This paper studies the operation of a DOAS intended to remove the ventilation air and space latent load in different Spanish climates during the summer season. The model developed in TRNSYS was validated with experimental data using the root mean standard error (RMSE). Maximum RMSE of 0.94 °C and 0.472 g/kg were obtained for the temperatures and humidity ratios of the process and regeneration airflows. The RMSE for the compressor power input was of 52.2 W. The results obtained with the developed model showed that the DOAS exhibited better performance in humid climates with moderate temperatures (Bilbao and Barcelona). It was also found that its application in dry climates (Madrid) was not appropriate, and that a high outdoor temperature lowered the DOAS efficiency when comparing cities with similar latent loads (Bilbao and Sevilla) or when comparing residential and commercial schedules.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"1 1","pages":"111 - 97"},"PeriodicalIF":1.5,"publicationDate":"2020-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89759488","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 : 2020-04-02DOI: 10.1080/14733315.2018.1549308
J. Seifert, Lars Schinke, M. Beyer
Abstract Thermal comfort is a very important issue for the design of HVAC systems. The aspects of thermal comfort are also significant in the operation of the heating/cooling systems in rooms. Many investigations studied the stationary boundary conditions, while transient conditions were not in focus. Therefore, this paper describes measurements carried out in a climate room under transient conditions. After an introduction, the second part of this paper gives an overview about the experimental setup and the methodology of the dynamic investigations. The third part describes the main results of the analyzes. The fourth part includes a discussion of these results and the contribution to potential regulation systems and further investigations. As a result of these analysis, it can be stated, that the individual comfort temperature as set by the user is mostly (operative room temperature). With regard to the dynamic behavior, it must be concluded that most subjects accept a room temperature increase of without directly expressing a change request. When the operative temperature falls below the individual comfort temperature, the desire for an increase in the operative temperature is immediately expressed, even in the case of small deviations. The paper ends with a summary of the results.
{"title":"Analysis of transient thermal sensation for “overheating” and “subcooling” conditions in a room","authors":"J. Seifert, Lars Schinke, M. Beyer","doi":"10.1080/14733315.2018.1549308","DOIUrl":"https://doi.org/10.1080/14733315.2018.1549308","url":null,"abstract":"Abstract Thermal comfort is a very important issue for the design of HVAC systems. The aspects of thermal comfort are also significant in the operation of the heating/cooling systems in rooms. Many investigations studied the stationary boundary conditions, while transient conditions were not in focus. Therefore, this paper describes measurements carried out in a climate room under transient conditions. After an introduction, the second part of this paper gives an overview about the experimental setup and the methodology of the dynamic investigations. The third part describes the main results of the analyzes. The fourth part includes a discussion of these results and the contribution to potential regulation systems and further investigations. As a result of these analysis, it can be stated, that the individual comfort temperature as set by the user is mostly (operative room temperature). With regard to the dynamic behavior, it must be concluded that most subjects accept a room temperature increase of without directly expressing a change request. When the operative temperature falls below the individual comfort temperature, the desire for an increase in the operative temperature is immediately expressed, even in the case of small deviations. The paper ends with a summary of the results.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"45 1","pages":"85 - 96"},"PeriodicalIF":1.5,"publicationDate":"2020-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78716447","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 : 2020-04-02DOI: 10.1080/14733315.2019.1615219
Marieli Azoia Lukiantchuki, Alessandra Prata Shimomura, F. Marques da Silva, R. Caram
Abstract Sheds roof is a natural ventilation strategy that presents roof openings working as air collectors or extractors. A detailed review of the literature indicates a lack of research analyzing the impact of different sheds roof shapes and roof configurations on natural ventilation potential. This paper aim is to evaluate the impact of changes in distance and alignment between windcatcher and leeward sheds roof. The methodology was Computational Fluid Dynamic (CFD) simulation. Tests were performed in an atmospheric boundary layer wind tunnel on a 1:15 scale model to evaluate the accuracy of CFD simulation in different design configurations of sheds roof. The analysis showed that CFD simulations are generally in good agreement with the wind tunnel tests. The difference between the most of the monitored points in the two tools used had errors below 10%. Besides this, the results show that changes in alignment of the sheds and increasing the distance between them decrease and increase the internal airflow to the leeward and windward sheds roof, respectively. In the first case it is due to the reduction in the sheds openings area. In the second these changes turn the sheds more effective in the air capture.
{"title":"Wind tunnel and CFD analysis of wind-induced natural ventilation in sheds roof building: impact of alignment and distance between sheds","authors":"Marieli Azoia Lukiantchuki, Alessandra Prata Shimomura, F. Marques da Silva, R. Caram","doi":"10.1080/14733315.2019.1615219","DOIUrl":"https://doi.org/10.1080/14733315.2019.1615219","url":null,"abstract":"Abstract Sheds roof is a natural ventilation strategy that presents roof openings working as air collectors or extractors. A detailed review of the literature indicates a lack of research analyzing the impact of different sheds roof shapes and roof configurations on natural ventilation potential. This paper aim is to evaluate the impact of changes in distance and alignment between windcatcher and leeward sheds roof. The methodology was Computational Fluid Dynamic (CFD) simulation. Tests were performed in an atmospheric boundary layer wind tunnel on a 1:15 scale model to evaluate the accuracy of CFD simulation in different design configurations of sheds roof. The analysis showed that CFD simulations are generally in good agreement with the wind tunnel tests. The difference between the most of the monitored points in the two tools used had errors below 10%. Besides this, the results show that changes in alignment of the sheds and increasing the distance between them decrease and increase the internal airflow to the leeward and windward sheds roof, respectively. In the first case it is due to the reduction in the sheds openings area. In the second these changes turn the sheds more effective in the air capture.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"1 1","pages":"141 - 162"},"PeriodicalIF":1.5,"publicationDate":"2020-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77732418","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 : 2020-03-19DOI: 10.1080/14733315.2020.1732056
D. Zukowska, G. Rojas, E. Burman, G. Guyot, María del Carmen Bocanegra-Yáñez, J. Laverge, G. Cao, J. Kolarik
Abstract This paper reports the results of an interview survey conducted among different stakeholders involved in design, installation and operation of residential ventilation in seven European countries. In total 44 interviews were performed. The results provide a valuable snapshot of current practices and insights into potential barriers and challenges regarding installation of mechanical ventilation in low-energy residences to maintain high indoor air quality (IAQ). The results show that mechanical ventilation with heat recovery is becoming a common choice in new low energy residences in Europe. However, there are countries that apply airing or other types of ventilation such as mechanical exhaust or natural ventilation due to tradition, national legislation, climatic conditions and/or cost reasons. Demand-controlled ventilation (DCV) is often allowed or even recommended in standards, but rarely implemented in practice, except for exhaust-only humidity-based DCV in France and Belgium. The main barriers against mechanical ventilation seem to be high capital cost, space requirements and duct routing. The respondents commonly reported problems resulting from poor construction, lack of commissioning and/or maintenance. The main needs to be identified in the survey were more legislative pushes including more flexibility in legislation, a coordinated approach to energy efficiency and IAQ, and control mechanisms to ensure good implementation and operation.
{"title":"Ventilation in low energy residences – a survey on code requirements, implementation barriers and operational challenges from seven European countries","authors":"D. Zukowska, G. Rojas, E. Burman, G. Guyot, María del Carmen Bocanegra-Yáñez, J. Laverge, G. Cao, J. Kolarik","doi":"10.1080/14733315.2020.1732056","DOIUrl":"https://doi.org/10.1080/14733315.2020.1732056","url":null,"abstract":"Abstract This paper reports the results of an interview survey conducted among different stakeholders involved in design, installation and operation of residential ventilation in seven European countries. In total 44 interviews were performed. The results provide a valuable snapshot of current practices and insights into potential barriers and challenges regarding installation of mechanical ventilation in low-energy residences to maintain high indoor air quality (IAQ). The results show that mechanical ventilation with heat recovery is becoming a common choice in new low energy residences in Europe. However, there are countries that apply airing or other types of ventilation such as mechanical exhaust or natural ventilation due to tradition, national legislation, climatic conditions and/or cost reasons. Demand-controlled ventilation (DCV) is often allowed or even recommended in standards, but rarely implemented in practice, except for exhaust-only humidity-based DCV in France and Belgium. The main barriers against mechanical ventilation seem to be high capital cost, space requirements and duct routing. The respondents commonly reported problems resulting from poor construction, lack of commissioning and/or maintenance. The main needs to be identified in the survey were more legislative pushes including more flexibility in legislation, a coordinated approach to energy efficiency and IAQ, and control mechanisms to ensure good implementation and operation.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"1 1","pages":"83 - 102"},"PeriodicalIF":1.5,"publicationDate":"2020-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87558280","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 : 2020-01-26DOI: 10.1080/14733315.2019.1710059
Zahra Tavakolian, O. Abouali, M. Yaghoubi
Abstract In this study, smoke evacuation in two kinds of subway station platform models, namely: an island platform station and a two side platforms station is simulated in a three-dimensional configuration. FDS 6.1.1 (Fire Dynamic Simulator) software has been employed to perform numerical simulations. The results showed noticeable effects of platform architecture on the process of smoke evacuation and emission spreading. The location of the connecting stairs (station accesses) between floors in both types of subway stations, installing the walls around these stairs in island platform type, the presence or absence of fireproof and antismoke curtains in suitable areas in two side platforms type have significant impacts on the smoke spreading. At the end, after the comparison between smoke dispersion in these two types of subway's platform, different architecture corrections were suggested and evaluated. Overall, it is concluded that an island platform station is more challenging in smoke control point of view, because the openings at the ceiling of the platform (stairway path) provide a convenient space for smoke to escape to the upper floors. In summary station architecture and even the smallest architectural changes at a subway station can change the smoke dispersion in space.
{"title":"3D simulations of smoke exhaust system in two types of subway station platforms","authors":"Zahra Tavakolian, O. Abouali, M. Yaghoubi","doi":"10.1080/14733315.2019.1710059","DOIUrl":"https://doi.org/10.1080/14733315.2019.1710059","url":null,"abstract":"Abstract In this study, smoke evacuation in two kinds of subway station platform models, namely: an island platform station and a two side platforms station is simulated in a three-dimensional configuration. FDS 6.1.1 (Fire Dynamic Simulator) software has been employed to perform numerical simulations. The results showed noticeable effects of platform architecture on the process of smoke evacuation and emission spreading. The location of the connecting stairs (station accesses) between floors in both types of subway stations, installing the walls around these stairs in island platform type, the presence or absence of fireproof and antismoke curtains in suitable areas in two side platforms type have significant impacts on the smoke spreading. At the end, after the comparison between smoke dispersion in these two types of subway's platform, different architecture corrections were suggested and evaluated. Overall, it is concluded that an island platform station is more challenging in smoke control point of view, because the openings at the ceiling of the platform (stairway path) provide a convenient space for smoke to escape to the upper floors. In summary station architecture and even the smallest architectural changes at a subway station can change the smoke dispersion in space.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"35 1","pages":"65 - 81"},"PeriodicalIF":1.5,"publicationDate":"2020-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81406461","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 : 2020-01-16DOI: 10.1080/14733315.2019.1704539
Jianjie Cheng, Xiaoyi Niu, Rui Zhang, Xidong Zhu, Song Lu, Bin Zhou, Xianting Li
Abstract With the wide application of electronic surgical equipment, the generation of surgical smoke is inevitable. Surgical smoke will not only obstruct the operator's visibility, but also release toxic and harmful substances into the air, which will make the operator a headache and cause inflammation of the eyes and mucous membranes. In order to evaluate whether the existing operating room ventilation system can give priority to control the diffusion of surgical smoke, it is necessary to understand the generation, release, transmission and elimination performance of surgical smoke. This paper studied the rule of the influence of surgical smoke in different areas of the operating room through experiments, and verified by the three-area heterogeneous model. At a static state, the cleanliness level of the operating area and the surrounding area is ISO4 and ISO6. When there is staff activity, the operating room is in a dynamic state, and the operating area and the surrounding area are ISO7. When there is surgical smoke, the cleanliness level of the operating area is reduced to ISO8, and the surrounding area has little influence. This indicates that personnel activities and surgical smoke in the operating room have a great impact on the operating room environment.
{"title":"Experimental study on influence of personnel activity and surgical smoke on indoor environment inside clean operating room","authors":"Jianjie Cheng, Xiaoyi Niu, Rui Zhang, Xidong Zhu, Song Lu, Bin Zhou, Xianting Li","doi":"10.1080/14733315.2019.1704539","DOIUrl":"https://doi.org/10.1080/14733315.2019.1704539","url":null,"abstract":"Abstract With the wide application of electronic surgical equipment, the generation of surgical smoke is inevitable. Surgical smoke will not only obstruct the operator's visibility, but also release toxic and harmful substances into the air, which will make the operator a headache and cause inflammation of the eyes and mucous membranes. In order to evaluate whether the existing operating room ventilation system can give priority to control the diffusion of surgical smoke, it is necessary to understand the generation, release, transmission and elimination performance of surgical smoke. This paper studied the rule of the influence of surgical smoke in different areas of the operating room through experiments, and verified by the three-area heterogeneous model. At a static state, the cleanliness level of the operating area and the surrounding area is ISO4 and ISO6. When there is staff activity, the operating room is in a dynamic state, and the operating area and the surrounding area are ISO7. When there is surgical smoke, the cleanliness level of the operating area is reduced to ISO8, and the surrounding area has little influence. This indicates that personnel activities and surgical smoke in the operating room have a great impact on the operating room environment.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"6 1","pages":"50 - 64"},"PeriodicalIF":1.5,"publicationDate":"2020-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79617966","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 : 2020-01-02DOI: 10.1080/14733315.2018.1544730
Yan Tong, Kai Lin, Q. Hu, X. Niu, Jun-huan Peng, D. Huo, Wenjie Yan
Abstract Large space buildings often have high HVAC energy consumption, and the thermal pressure ventilation can be utilized to reduce the using of chiller. Temperatures were tested on two naturally ventilated large spaces, and it increased linearly towards the ceiling with its gradients α being in range of 0.1–0.4 °C/m. The traditional stack effect model is modified by introducing thermal stratification. For three hot and humid cities in China, the acceptable indoor air temperatures are discussed and determined based on its monthly outdoor air temperatures. Investigations are done to find out parameters’ influences on the indoor thermal environment. It is known that both the dimensionless neutral plane height Hn/H and the volumetric flow rate per unit floor area l are not sensitive to outdoor climate, but decrease with increasing of the lower-upper opening area ratio Rab; the occupied air temperature tn increases with the increase of Rab or q but with the decrease of α or H; under case of 0.2 °C/m and 150 W/m2, Nanjing has the maximum scopes of available upper opening areas in transition season to achieve natural ventilation cooling potential. Such results would be useful in design and management of upper openings for large spaces.
{"title":"Field measurements on thermal stratification and cooling potential of natural ventilation for large space buildings","authors":"Yan Tong, Kai Lin, Q. Hu, X. Niu, Jun-huan Peng, D. Huo, Wenjie Yan","doi":"10.1080/14733315.2018.1544730","DOIUrl":"https://doi.org/10.1080/14733315.2018.1544730","url":null,"abstract":"Abstract Large space buildings often have high HVAC energy consumption, and the thermal pressure ventilation can be utilized to reduce the using of chiller. Temperatures were tested on two naturally ventilated large spaces, and it increased linearly towards the ceiling with its gradients α being in range of 0.1–0.4 °C/m. The traditional stack effect model is modified by introducing thermal stratification. For three hot and humid cities in China, the acceptable indoor air temperatures are discussed and determined based on its monthly outdoor air temperatures. Investigations are done to find out parameters’ influences on the indoor thermal environment. It is known that both the dimensionless neutral plane height Hn/H and the volumetric flow rate per unit floor area l are not sensitive to outdoor climate, but decrease with increasing of the lower-upper opening area ratio Rab; the occupied air temperature tn increases with the increase of Rab or q but with the decrease of α or H; under case of 0.2 °C/m and 150 W/m2, Nanjing has the maximum scopes of available upper opening areas in transition season to achieve natural ventilation cooling potential. Such results would be useful in design and management of upper openings for large spaces.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"30 1","pages":"49 - 62"},"PeriodicalIF":1.5,"publicationDate":"2020-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82173633","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 : 2020-01-02DOI: 10.1080/14733315.2018.1549305
Ya-Qiong Wang, Shuoshuo Xu, Rui Ren, Shuangzhuo Zhang, Z. Ren
Abstract To solve the imbalanced problem of wind pressure between left tunnel and right tunnel in the large-slopping tunnel, the complementary ventilation system is proposed, and the design theory and calculation method are also discussed. Results from a experiment carried out in a model tunnel (1:10) with complementary ventilation are presented and applied to the Dabieshan tunnel. It is found that the twin-tube complementary ventilation system can bridge two tunnels and exchange air between tunnels to ensure adequate air quality. The fresh air in the downhill tunnel can be transfer into the uphill tunnel to dilute air in the uphill tunnel. Field measurements were performed in the Dabieshan tunnel on wind speed, CO concentration, and VI (visibility index) concentration. Measurement results also indicate that the twin-tube complementary ventilation system can meet the ventilation requirements for tunnels. Compared with traditional ventilation systems, the complementary ventilation can be used to ensure adequate air quality in tunnels by eliminating the ventilation shaft in uphill tunnel and saving initial investments and operation costs.
{"title":"Application of the twin-tube complementary ventilation system in large-slopping road tunnels in China","authors":"Ya-Qiong Wang, Shuoshuo Xu, Rui Ren, Shuangzhuo Zhang, Z. Ren","doi":"10.1080/14733315.2018.1549305","DOIUrl":"https://doi.org/10.1080/14733315.2018.1549305","url":null,"abstract":"Abstract To solve the imbalanced problem of wind pressure between left tunnel and right tunnel in the large-slopping tunnel, the complementary ventilation system is proposed, and the design theory and calculation method are also discussed. Results from a experiment carried out in a model tunnel (1:10) with complementary ventilation are presented and applied to the Dabieshan tunnel. It is found that the twin-tube complementary ventilation system can bridge two tunnels and exchange air between tunnels to ensure adequate air quality. The fresh air in the downhill tunnel can be transfer into the uphill tunnel to dilute air in the uphill tunnel. Field measurements were performed in the Dabieshan tunnel on wind speed, CO concentration, and VI (visibility index) concentration. Measurement results also indicate that the twin-tube complementary ventilation system can meet the ventilation requirements for tunnels. Compared with traditional ventilation systems, the complementary ventilation can be used to ensure adequate air quality in tunnels by eliminating the ventilation shaft in uphill tunnel and saving initial investments and operation costs.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"28 1","pages":"63 - 82"},"PeriodicalIF":1.5,"publicationDate":"2020-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85259205","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 : 2020-01-02DOI: 10.1080/14733315.2018.1524196
Mohsen M. Barsim, M. Bassily, H. El-Batsh, Yaser A. Rihan, M. M. Sherif
Abstract This study investigates the measurements data attained in Murcia Atrium fire tests (Gutiérrez-Montes, Sanmiguel-Rojas, Viedma, & Rein) using general CFD code, CFX-16.2 ( CFX-16.2, ANSYS, Inc.). Experiments were executed by burning heptane as a fuel for three different fires capacities, (1.32, 2.28 and 2.34 MW). Historically, CFX was validated with experimental data for compartment fires including natural ventilation only. In this paper validation was performed for developing fires during transient period in a large space, including the effect of combined natural and forced ventilation. Two different combustion models i.e. Non-combustion model and Eddy Dissipation Model (EDM) were used to represent the combustion of heptane. Four different approaches were employed to determine the predicted dynamic behavior of the smoke height and to evaluate the accuracy of CFX predictions. The results display CFX predictions have a reasonable concord with the experimental data. Therefore, CFX can be a valid tool for performance-based engineering to evaluate the smoke systems required for complex enclosed structures.
{"title":"Numerical simulation of an experimental atrium fires in combined natural and forced ventilation by CFD","authors":"Mohsen M. Barsim, M. Bassily, H. El-Batsh, Yaser A. Rihan, M. M. Sherif","doi":"10.1080/14733315.2018.1524196","DOIUrl":"https://doi.org/10.1080/14733315.2018.1524196","url":null,"abstract":"Abstract This study investigates the measurements data attained in Murcia Atrium fire tests (Gutiérrez-Montes, Sanmiguel-Rojas, Viedma, & Rein) using general CFD code, CFX-16.2 ( CFX-16.2, ANSYS, Inc.). Experiments were executed by burning heptane as a fuel for three different fires capacities, (1.32, 2.28 and 2.34 MW). Historically, CFX was validated with experimental data for compartment fires including natural ventilation only. In this paper validation was performed for developing fires during transient period in a large space, including the effect of combined natural and forced ventilation. Two different combustion models i.e. Non-combustion model and Eddy Dissipation Model (EDM) were used to represent the combustion of heptane. Four different approaches were employed to determine the predicted dynamic behavior of the smoke height and to evaluate the accuracy of CFX predictions. The results display CFX predictions have a reasonable concord with the experimental data. Therefore, CFX can be a valid tool for performance-based engineering to evaluate the smoke systems required for complex enclosed structures.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"12 1","pages":"1 - 24"},"PeriodicalIF":1.5,"publicationDate":"2020-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81498931","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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