Pub Date : 2022-06-02DOI: 10.1177/01436244221106342
Lufang Chen, Kai Zhang, Ge Song, Fei Li
Radiative cooling has been demonstrated as an effective way to reduce building energy consumption especially for the recently developed diurnal radiative cooling materials. The most convenient application of radiative cooling materials is configured as the cool roofs. However, cool roofs will produce cooling energy throughout the year which will lead to the increase of heating penalty in the heating season. This phenomenon will offset part of the cooling benefit from radiative cooling. The ventilated roofs are also commonly employed in buildings for achieving energy-saving by reducing the heat gain from the roof to the building. To reduce the influence of radiative cooling in the heating season, a radiative cooling-based ventilated roof (RCVR) is proposed in this study by integrating the ventilated roof with the radiative cooling-based cool roof. The process of the heat transfer through RCVR is analyzed, and the simplified heat transfer model is developed. And then the effect of RCVR configuration on the room temperature is discussed in detail through CFD simulation. Finally, the annual electricity consumption of the building with RCVR is derived using EnergyPlus. The results show that the annual comprehensive performance of RCVR is superior to the cool roof and original roof since the total annual electricity consumption of the building with RCVR can be decreased by 21.8% and 16.9% compared with that of cool roof and original roof. Practical application: A radiative cooling-based ventilated roof (RCVR) is proposed by integrating the ventilated roof with the radiative cooling-based cool roof. The results show that the annual comprehensive performance of RCVR is superior to the cool roof and original roof. This study can provide the guiding significance for the application of RCVR, in which the building energy consumption can be further decreased for the application of radiative cooling in buildings.
{"title":"Study on the cooling performance of a radiative cooling-based ventilated roof for its application in buildings","authors":"Lufang Chen, Kai Zhang, Ge Song, Fei Li","doi":"10.1177/01436244221106342","DOIUrl":"https://doi.org/10.1177/01436244221106342","url":null,"abstract":"Radiative cooling has been demonstrated as an effective way to reduce building energy consumption especially for the recently developed diurnal radiative cooling materials. The most convenient application of radiative cooling materials is configured as the cool roofs. However, cool roofs will produce cooling energy throughout the year which will lead to the increase of heating penalty in the heating season. This phenomenon will offset part of the cooling benefit from radiative cooling. The ventilated roofs are also commonly employed in buildings for achieving energy-saving by reducing the heat gain from the roof to the building. To reduce the influence of radiative cooling in the heating season, a radiative cooling-based ventilated roof (RCVR) is proposed in this study by integrating the ventilated roof with the radiative cooling-based cool roof. The process of the heat transfer through RCVR is analyzed, and the simplified heat transfer model is developed. And then the effect of RCVR configuration on the room temperature is discussed in detail through CFD simulation. Finally, the annual electricity consumption of the building with RCVR is derived using EnergyPlus. The results show that the annual comprehensive performance of RCVR is superior to the cool roof and original roof since the total annual electricity consumption of the building with RCVR can be decreased by 21.8% and 16.9% compared with that of cool roof and original roof. Practical application: A radiative cooling-based ventilated roof (RCVR) is proposed by integrating the ventilated roof with the radiative cooling-based cool roof. The results show that the annual comprehensive performance of RCVR is superior to the cool roof and original roof. This study can provide the guiding significance for the application of RCVR, in which the building energy consumption can be further decreased for the application of radiative cooling in buildings.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41622118","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 : 2022-05-16DOI: 10.1177/01436244221100362
Pouya Rikhtehgar, M. Haeri
In this paper, a reduced multiple-model predictive controller based on gap metric and stability margin is presented to control heating, ventilating, and air conditioning (HVAC) systems. To tackle the strong nonlinearity and large number of degrees of freedom in HVAC system, two approaches, called Reduced Order Model Bank-Multiple Model (ROMB-MM) and Multiple Model-Reduced Order Model (MM-ROM), are introduced. In the first approach, the order reduction is performed prior to multiple models selection and in the second one multiple models selection is implemented before the model order reduction. Furthermore, soft switching is employed to enhance the closed-loop performance as well as to gain optimal energy consumption. In order to evaluate the proposed approaches, a sliding mode controller is also simulated to compare the results in terms of energy and cost savings, transient and steady-state responses, and robustness against external disturbances and model uncertainties. Practical application: HVAC control systems are in charge of control indoor air temperature with energy optimization so that the thermal comfort is maintained. But how to model HVAC systems in each weather conditions is a significant challenge. A simpler and more accurate model will provide more efficient control of indoor air temperature. This paper suggests model order reduction and multiple model to select the simple linear model(s) in extreme weather conditions. The effectiveness of the proposed method can be implemented on nonlinear HVAC system.
{"title":"Reduced multiple model predictive control of an heating, ventilating, and air conditioning system using gap metric and stability margin","authors":"Pouya Rikhtehgar, M. Haeri","doi":"10.1177/01436244221100362","DOIUrl":"https://doi.org/10.1177/01436244221100362","url":null,"abstract":"In this paper, a reduced multiple-model predictive controller based on gap metric and stability margin is presented to control heating, ventilating, and air conditioning (HVAC) systems. To tackle the strong nonlinearity and large number of degrees of freedom in HVAC system, two approaches, called Reduced Order Model Bank-Multiple Model (ROMB-MM) and Multiple Model-Reduced Order Model (MM-ROM), are introduced. In the first approach, the order reduction is performed prior to multiple models selection and in the second one multiple models selection is implemented before the model order reduction. Furthermore, soft switching is employed to enhance the closed-loop performance as well as to gain optimal energy consumption. In order to evaluate the proposed approaches, a sliding mode controller is also simulated to compare the results in terms of energy and cost savings, transient and steady-state responses, and robustness against external disturbances and model uncertainties. Practical application: HVAC control systems are in charge of control indoor air temperature with energy optimization so that the thermal comfort is maintained. But how to model HVAC systems in each weather conditions is a significant challenge. A simpler and more accurate model will provide more efficient control of indoor air temperature. This paper suggests model order reduction and multiple model to select the simple linear model(s) in extreme weather conditions. The effectiveness of the proposed method can be implemented on nonlinear HVAC system.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47155383","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 : 2022-05-14DOI: 10.1177/01436244221100599
Zhichao Jiao, K. Emura
In the common method of compiling outdoor design conditions by annual cumulative frequency of occurrence, the probability of simultaneous occurrence of the selected meteorological elements is not considered, which may lead to an overestimation of air-conditioning equipment capacity design. This paper aims at developing a novel approach for producing the outdoor design conditions, taking into consideration the dependency between the air temperature and global solar radiation, which have a strong influence on the HVAC capacity design. These two meteorological elements are analyzed for specific simultaneous occurrence probability based on the joint distribution. For this purpose, the copula approach which can describe the dependence between these two meteorological elements is used for modeling the joint distribution function. We investigated copula family selection for air temperature and global solar radiation at each hour of hourly weather data for 10 years from 2001 to 2010 in Osaka, Japan. The Joe-Frank copula has the best fitting results for the dependence between the air temperature and global solar radiation. According to the comparison of original exceeding probability and simultaneous occurrence probability, the results show that the design conditions based on the common method can significantly exceed that of the simultaneous occurrence probability method. Practical Application: Outdoor design conditions are used in the building design stage to estimate building performance and select the appropriate air conditioning equipment capacity. Excessive air-conditioning capacity may lead to a large amount of unnecessary energy wastage. Insufficient capacity may lead to not meeting the desired indoor environment conditions of utilization in extreme weather conditions, especially for large office buildings. Therefore, this paper provides a new approach to generate more realistic meteorological conditions for air-conditioning design to improve building energy efficiency.
{"title":"Joint probability distribution of air temperature and global solar radiation for outdoor design conditions based on copula approach","authors":"Zhichao Jiao, K. Emura","doi":"10.1177/01436244221100599","DOIUrl":"https://doi.org/10.1177/01436244221100599","url":null,"abstract":"In the common method of compiling outdoor design conditions by annual cumulative frequency of occurrence, the probability of simultaneous occurrence of the selected meteorological elements is not considered, which may lead to an overestimation of air-conditioning equipment capacity design. This paper aims at developing a novel approach for producing the outdoor design conditions, taking into consideration the dependency between the air temperature and global solar radiation, which have a strong influence on the HVAC capacity design. These two meteorological elements are analyzed for specific simultaneous occurrence probability based on the joint distribution. For this purpose, the copula approach which can describe the dependence between these two meteorological elements is used for modeling the joint distribution function. We investigated copula family selection for air temperature and global solar radiation at each hour of hourly weather data for 10 years from 2001 to 2010 in Osaka, Japan. The Joe-Frank copula has the best fitting results for the dependence between the air temperature and global solar radiation. According to the comparison of original exceeding probability and simultaneous occurrence probability, the results show that the design conditions based on the common method can significantly exceed that of the simultaneous occurrence probability method. Practical Application: Outdoor design conditions are used in the building design stage to estimate building performance and select the appropriate air conditioning equipment capacity. Excessive air-conditioning capacity may lead to a large amount of unnecessary energy wastage. Insufficient capacity may lead to not meeting the desired indoor environment conditions of utilization in extreme weather conditions, especially for large office buildings. Therefore, this paper provides a new approach to generate more realistic meteorological conditions for air-conditioning design to improve building energy efficiency.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44545253","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 : 2022-05-11DOI: 10.1177/01436244221099426
A. Werner-Juszczuk
For environmental and economic reasons, it is necessary to search for heating systems solutions that are efficient and provide thermal comfort at a low investment cost. In this study, the optimum gap between aluminium radiant sheets in lightweight floor heating is determined, ensuring high system efficiency and low material consumption. Numerical calculations were performed using the ANSYS. The structures analysed consist of thermal insulation covered with a 0.3 mm thick aluminium sheet, wood-like board and ceramic tiles or panels. The average surface temperature and the temperature amplitude are determined for the construction with no gap between the sheets and with gaps of 10, 20, 30 and 40 mm. Increasing the gap size results in a decrease in the surface temperature and heat flux and an increase in temperature amplitude. For a 10–20 mm gap, the decrease in temperature (<0.47 K), relative heat flux drop (<4.4%) and increase in surface temperature amplitude (<1K) can be considered negligible at a water temperature of 25–40°C, pipe spacing of 0.075–0.150 m and the thermal resistance of the layers above the pipes ≤0.118 m2K/W. A gap of 10–20 mm compared to no gap reduces aluminium consumption, which is environmentally friendly while ensuring high system efficiency.
{"title":"Influence of gap size between aluminium radiant sheets on the efficiency of lightweight floor heating","authors":"A. Werner-Juszczuk","doi":"10.1177/01436244221099426","DOIUrl":"https://doi.org/10.1177/01436244221099426","url":null,"abstract":"For environmental and economic reasons, it is necessary to search for heating systems solutions that are efficient and provide thermal comfort at a low investment cost. In this study, the optimum gap between aluminium radiant sheets in lightweight floor heating is determined, ensuring high system efficiency and low material consumption. Numerical calculations were performed using the ANSYS. The structures analysed consist of thermal insulation covered with a 0.3 mm thick aluminium sheet, wood-like board and ceramic tiles or panels. The average surface temperature and the temperature amplitude are determined for the construction with no gap between the sheets and with gaps of 10, 20, 30 and 40 mm. Increasing the gap size results in a decrease in the surface temperature and heat flux and an increase in temperature amplitude. For a 10–20 mm gap, the decrease in temperature (<0.47 K), relative heat flux drop (<4.4%) and increase in surface temperature amplitude (<1K) can be considered negligible at a water temperature of 25–40°C, pipe spacing of 0.075–0.150 m and the thermal resistance of the layers above the pipes ≤0.118 m2K/W. A gap of 10–20 mm compared to no gap reduces aluminium consumption, which is environmentally friendly while ensuring high system efficiency.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44626326","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 : 2022-05-08DOI: 10.1177/01436244221099482
Yan Wang, Elizabeth Cooper, F. Tahmasebi, Jonathon Taylor, S. Stamp, P. Symonds, E. Burman, D. Mumovic
Indoor exposure to PM2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) has a substantial negative impact on people’s health. However, indoor PM2.5 can be controlled through effective ventilation and filtration. This study aimed to develop a smart control framework that (1) combines a portable home air purifier (HAP) and window control system to reduce indoor PM2.5 concentrations whilst maintaining thermal comfort; (2) evaluates the associated health impacts and additional energy use. The proposed framework was demonstrated through a simulation-based case study of a low-energy apartment. The simulation results showed that joint control of HAP and window openings has great potential to not only maintain thermal comfort but also achieve effective PM2.5 removal which, consequently, can lead to considerable health benefits at a low additional energy cost. Compared to similar previous studies, the strength of the proposed control framework lies in combining window operations and HAPs in the same system and including both thermal comfort and indoor PM2.5 as the control targets. This work also introduces a novel concept of linking a building control system with a health impact assessment, an important and innovative step in the creation of holistic and responsive building controls. Practical application: This study proposes a novel control framework that jointly controls portable home air purifiers (HAPs) and windows to maintain thermal comfort and achieve effective PM2.5 removal. The simulation results suggest that such a hybrid control strategy can result in considerable health benefits at low additional energy costs.
{"title":"Improving indoor air quality and occupant health through smart control of windows and portable air purifiers in residential buildings","authors":"Yan Wang, Elizabeth Cooper, F. Tahmasebi, Jonathon Taylor, S. Stamp, P. Symonds, E. Burman, D. Mumovic","doi":"10.1177/01436244221099482","DOIUrl":"https://doi.org/10.1177/01436244221099482","url":null,"abstract":"Indoor exposure to PM2.5 (particulate matter with aerodynamic diameter less than 2.5 μm) has a substantial negative impact on people’s health. However, indoor PM2.5 can be controlled through effective ventilation and filtration. This study aimed to develop a smart control framework that (1) combines a portable home air purifier (HAP) and window control system to reduce indoor PM2.5 concentrations whilst maintaining thermal comfort; (2) evaluates the associated health impacts and additional energy use. The proposed framework was demonstrated through a simulation-based case study of a low-energy apartment. The simulation results showed that joint control of HAP and window openings has great potential to not only maintain thermal comfort but also achieve effective PM2.5 removal which, consequently, can lead to considerable health benefits at a low additional energy cost. Compared to similar previous studies, the strength of the proposed control framework lies in combining window operations and HAPs in the same system and including both thermal comfort and indoor PM2.5 as the control targets. This work also introduces a novel concept of linking a building control system with a health impact assessment, an important and innovative step in the creation of holistic and responsive building controls. Practical application: This study proposes a novel control framework that jointly controls portable home air purifiers (HAPs) and windows to maintain thermal comfort and achieve effective PM2.5 removal. The simulation results suggest that such a hybrid control strategy can result in considerable health benefits at low additional energy costs.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43548573","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 : 2022-05-07DOI: 10.1177/01436244221097312
Ahmad Askari, M. Mahdavinejad, M. Ansari
The performance of a ventilation system affects air quality, thermal comfort, and energy consumption in indoor environments. To evaluate the performance of displacement ventilation under various room configurations, steady Reynolds Averaged Navier–Stokes (RANS) Computational Fluid Dynamics (CFD) simulations were used. The CFD model was validated using measurements of a full-scale test room. The age of air concept was used to evaluate the ventilation performance regarding indoor air quality. The PD index was used to control the case studies for draft risk. Twelve cases with different configurations were systematically studied and compared with the reference case. The configurations included plan aspect ratio, exhaust opening position, inlet position and geometry, and internal heat gains. The results showed that the overall ventilation performance of a room is less sensitive to room configurations compared with local ventilation performance around the occupants. However, almost in all cases, the occupants were exposed to better-than-average air quality in most cases. The results also indicated that when internal heat gains are small, displacement ventilation should be used with caution. Practical application: Any HVAC system design is based on assumptions made for ventilation performance. Comprehensive knowledge of the influential factors is critical for an efficient design. Regarding the architecture and interior design, the architects are also involved in the ventilation systems since they have an axial role in decision making for room configuration, including but not limited to room geometry, the position of inlet and outlet air terminals, and heat/pollutant sources. Consequently, the impact of room configuration on ventilation performance is of practical importance in the architecture, engineering, and construction industry.
{"title":"Investigation of displacement ventilation performance under various room configurations using computational fluid dynamics simulation","authors":"Ahmad Askari, M. Mahdavinejad, M. Ansari","doi":"10.1177/01436244221097312","DOIUrl":"https://doi.org/10.1177/01436244221097312","url":null,"abstract":"The performance of a ventilation system affects air quality, thermal comfort, and energy consumption in indoor environments. To evaluate the performance of displacement ventilation under various room configurations, steady Reynolds Averaged Navier–Stokes (RANS) Computational Fluid Dynamics (CFD) simulations were used. The CFD model was validated using measurements of a full-scale test room. The age of air concept was used to evaluate the ventilation performance regarding indoor air quality. The PD index was used to control the case studies for draft risk. Twelve cases with different configurations were systematically studied and compared with the reference case. The configurations included plan aspect ratio, exhaust opening position, inlet position and geometry, and internal heat gains. The results showed that the overall ventilation performance of a room is less sensitive to room configurations compared with local ventilation performance around the occupants. However, almost in all cases, the occupants were exposed to better-than-average air quality in most cases. The results also indicated that when internal heat gains are small, displacement ventilation should be used with caution. Practical application: Any HVAC system design is based on assumptions made for ventilation performance. Comprehensive knowledge of the influential factors is critical for an efficient design. Regarding the architecture and interior design, the architects are also involved in the ventilation systems since they have an axial role in decision making for room configuration, including but not limited to room geometry, the position of inlet and outlet air terminals, and heat/pollutant sources. Consequently, the impact of room configuration on ventilation performance is of practical importance in the architecture, engineering, and construction industry.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45744215","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 : 2022-05-04DOI: 10.1177/01436244221095195
A. So, L. Al-Sharif, Ricky C. Chan
Recent studies have revealed that the dominant traffic pattern of a modern high-rise building is much more complicated than the conventional up-peak model, i.e. incoming traffic only, upon which the popular formula of round trip time (RTT) calculation is based. RTT calculation is still recommended by ISO 8100:32:2020 and CIBSE Guide D: 2020 to precede any computer simulation. Nowadays, the concern is more on the lunch peak with a mixture of incoming, outgoing and interfloor traffic patterns. Moreover, the independent one-passenger arrival model should be replaced by the more practical batch arrival model, in particular during lunch-time peak. This article first summarizes what were previously published on the universal RTT evaluation for mixed traffic conditions, highlights the main arguments, updates and supplements some previously introduced formulae such as that related to coincidental stops, uses more symmetrical and easily manipulated graphics, and, second in particular, brings in the concept of batch arrivals of any desirable probability distribution, where the conventional independent one-passenger arrival up-peak model now becomes a special case. A step-by-step presentation is adopted for convenient application of this universal calculation approach by designers and the detailed verification of the whole process by Monte Carlo simulation is also included. Practical applications: Round trip time calculation is still recommended the first step of traffic design by the industry but it should reasonably include the consideration of mixed traffic patterns, versus a pure incoming (i.e. up-peak) approach in the past. Such universal RTT calculation was described in several articles previously, but with some missing details. Here, the whole process is summarized, updated and presented in a more graphical way for convenient use by designers. Furthermore, the more contemporarily practical batch passenger arrival mode is included in this universal RTT model as an extension to the methodology so that what are discussed in this article include incoming, outgoing, interfloor traffic patterns with batch arrival consideration. It is hoped that this article could provide a comprehensive universal RTT methodology that can eventually be popularly applied globally by designers and consultants.
{"title":"Universal elevator round trip time calculation for general traffic conditions with extension to batch arrivals","authors":"A. So, L. Al-Sharif, Ricky C. Chan","doi":"10.1177/01436244221095195","DOIUrl":"https://doi.org/10.1177/01436244221095195","url":null,"abstract":"Recent studies have revealed that the dominant traffic pattern of a modern high-rise building is much more complicated than the conventional up-peak model, i.e. incoming traffic only, upon which the popular formula of round trip time (RTT) calculation is based. RTT calculation is still recommended by ISO 8100:32:2020 and CIBSE Guide D: 2020 to precede any computer simulation. Nowadays, the concern is more on the lunch peak with a mixture of incoming, outgoing and interfloor traffic patterns. Moreover, the independent one-passenger arrival model should be replaced by the more practical batch arrival model, in particular during lunch-time peak. This article first summarizes what were previously published on the universal RTT evaluation for mixed traffic conditions, highlights the main arguments, updates and supplements some previously introduced formulae such as that related to coincidental stops, uses more symmetrical and easily manipulated graphics, and, second in particular, brings in the concept of batch arrivals of any desirable probability distribution, where the conventional independent one-passenger arrival up-peak model now becomes a special case. A step-by-step presentation is adopted for convenient application of this universal calculation approach by designers and the detailed verification of the whole process by Monte Carlo simulation is also included. Practical applications: Round trip time calculation is still recommended the first step of traffic design by the industry but it should reasonably include the consideration of mixed traffic patterns, versus a pure incoming (i.e. up-peak) approach in the past. Such universal RTT calculation was described in several articles previously, but with some missing details. Here, the whole process is summarized, updated and presented in a more graphical way for convenient use by designers. Furthermore, the more contemporarily practical batch passenger arrival mode is included in this universal RTT model as an extension to the methodology so that what are discussed in this article include incoming, outgoing, interfloor traffic patterns with batch arrival consideration. It is hoped that this article could provide a comprehensive universal RTT methodology that can eventually be popularly applied globally by designers and consultants.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46849337","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 : 2022-05-01DOI: 10.1177/01436244221098335
of using vision-based systems in indoor environments, such as fast detection, propagation tracking, informing fi re fi ghters and combining detection with an HVAC system to allow controlled ventilation to aid in the decay of the fi re. The initial results presented here show the practicality of such an approach that could potentially be integrated with fi re fi ghting systems for various building spaces and environments. Project GreenSCIES, is a detailed design study to develop a Smart, Local Energy System (SLES) for a large community in the London Borough of Islington. Our consortium have developed an innovative SLES concept, centred around a fi fth generation district heating and cooling network. The GS ambient loop systems have negligible losses and much greater ef fi ciencies than traditional district heat networks. As recognised by the UK Government ’ s Heat and Buildings Strategy, ambient loop systems should be considered where large-scale neighbourhood regeneration occurs. The proposed SLES concept applied to wider urban areas could deliver signi fi cant carbon emission savings in the UK. This work investigates the cooling potential behind a practical project that involves recovering waste heat from the LU network. As electri fi cation leads to an increased deployment of heat pump and district heating systems, waste heat could become a valuable resource for maximising energy ef fi ciency, even more so when additional cooling bene fi ts can be achieved. This paper aims to explore the impacts of cooling on railway tunnels, emphasising how secondary bene fi ts, which are many times overlooked, could be critical to making waste heat recovery economically feasible, maximising its potential as a key technology for decarbonising heat. These research results can be used as a reference for selection of the installation position of the outdoor unit and blade angle of the louvre in the practical engineering application when single and double outdoor units are installed in a recess, which is of great signi fi cance in improving the EER of air conditioners and saving energy. Good understanding of occupant comfort is necessary to reduce building energy consumption without compromising comfort. This article explores the use of ASHRAE Comfort Database II for determining occupant comfort in MM buildings in temperate oceanic climates and the limitations faced therein. A practical and publicly accessible database developed based on the recommendations from this study will improve thermal comfort models and enable better prediction of occupant comfort while improving energy ef fi ciency substantially.
{"title":"Practical applications","authors":"","doi":"10.1177/01436244221098335","DOIUrl":"https://doi.org/10.1177/01436244221098335","url":null,"abstract":"of using vision-based systems in indoor environments, such as fast detection, propagation tracking, informing fi re fi ghters and combining detection with an HVAC system to allow controlled ventilation to aid in the decay of the fi re. The initial results presented here show the practicality of such an approach that could potentially be integrated with fi re fi ghting systems for various building spaces and environments. Project GreenSCIES, is a detailed design study to develop a Smart, Local Energy System (SLES) for a large community in the London Borough of Islington. Our consortium have developed an innovative SLES concept, centred around a fi fth generation district heating and cooling network. The GS ambient loop systems have negligible losses and much greater ef fi ciencies than traditional district heat networks. As recognised by the UK Government ’ s Heat and Buildings Strategy, ambient loop systems should be considered where large-scale neighbourhood regeneration occurs. The proposed SLES concept applied to wider urban areas could deliver signi fi cant carbon emission savings in the UK. This work investigates the cooling potential behind a practical project that involves recovering waste heat from the LU network. As electri fi cation leads to an increased deployment of heat pump and district heating systems, waste heat could become a valuable resource for maximising energy ef fi ciency, even more so when additional cooling bene fi ts can be achieved. This paper aims to explore the impacts of cooling on railway tunnels, emphasising how secondary bene fi ts, which are many times overlooked, could be critical to making waste heat recovery economically feasible, maximising its potential as a key technology for decarbonising heat. These research results can be used as a reference for selection of the installation position of the outdoor unit and blade angle of the louvre in the practical engineering application when single and double outdoor units are installed in a recess, which is of great signi fi cance in improving the EER of air conditioners and saving energy. Good understanding of occupant comfort is necessary to reduce building energy consumption without compromising comfort. This article explores the use of ASHRAE Comfort Database II for determining occupant comfort in MM buildings in temperate oceanic climates and the limitations faced therein. A practical and publicly accessible database developed based on the recommendations from this study will improve thermal comfort models and enable better prediction of occupant comfort while improving energy ef fi ciency substantially.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44112857","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 : 2022-04-24DOI: 10.1177/01436244221090586
Marco Tomé, P. Beirão, L. Roseiro, Frederico Santos
All around the world, modern elevators transport safely and comfortably millions of passengers and freight each day. Since modern elevators emerged at the beginning of the 19th century, several advances have risen in this transportation system. Among them, safety conditions were significantly improved. Therefore, modern elevators must be equipped with safety protection systems to assure safety conditions and avoid accidents. An overspeed governor is one of the components of such a safety system. It acts as a stopping mechanism when the elevator car reaches an excessive velocity, known as tripping speed. When the tripping speed is reached, the overspeed governor is mechanically locked and halts the rope, thus stopping the elevator car. This paper describes the development of a new measuring system able to measure the trigger velocity of an overspeed governor with the help of a graphical interface available on a mobile electronic device (smartphone or tablet). Practical application: A new overspeed governor velocity measuring system uses a mobile electronic device for non-contact velocity measurement. This new process may replace the inaccurate measuring system currently employed by maintenance technicians, thus increasing its reliability. The main objective consists of rigorously testing the operation of overspeed governors. The developed system guarantees the automatic execution of the test under several anomalous operating situations, thus allowing the user to have real-time access to the test data obtained through a graphical interface available on a mobile electronic device.
{"title":"Automatic velocity measurement system applied to elevator overspeed governors","authors":"Marco Tomé, P. Beirão, L. Roseiro, Frederico Santos","doi":"10.1177/01436244221090586","DOIUrl":"https://doi.org/10.1177/01436244221090586","url":null,"abstract":"All around the world, modern elevators transport safely and comfortably millions of passengers and freight each day. Since modern elevators emerged at the beginning of the 19th century, several advances have risen in this transportation system. Among them, safety conditions were significantly improved. Therefore, modern elevators must be equipped with safety protection systems to assure safety conditions and avoid accidents. An overspeed governor is one of the components of such a safety system. It acts as a stopping mechanism when the elevator car reaches an excessive velocity, known as tripping speed. When the tripping speed is reached, the overspeed governor is mechanically locked and halts the rope, thus stopping the elevator car. This paper describes the development of a new measuring system able to measure the trigger velocity of an overspeed governor with the help of a graphical interface available on a mobile electronic device (smartphone or tablet). Practical application: A new overspeed governor velocity measuring system uses a mobile electronic device for non-contact velocity measurement. This new process may replace the inaccurate measuring system currently employed by maintenance technicians, thus increasing its reliability. The main objective consists of rigorously testing the operation of overspeed governors. The developed system guarantees the automatic execution of the test under several anomalous operating situations, thus allowing the user to have real-time access to the test data obtained through a graphical interface available on a mobile electronic device.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44371113","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 : 2022-04-21DOI: 10.1177/01436244221085916
Rohit D Mangalekar, K. Gumaste
Stochastic models for estimating residential water demand use high-resolution field data consuming large costs and significant time. An attempt for the accurate estimation of water demand may result in its complex analytical model due to numerous factors affecting the water use event. Moreover, as the water supply system is always subjected to variations in demand, the accuracy of water demand estimation in its design can be side-lined. The water demand in residential buildings is mainly governed by the users’ characteristics and their daily schedule. In this view, the use of Fuzzy Logic can be advantageous to model the uncertainty in water demands. The presented study attempts to provide a methodology to estimate urban indoor residential water demand with the help of user-based end-use models in the absence of field data and generate various possible water demand patterns of fixtures. Usergroups were created for assuming spatial variations in water demand. Fuzzy Logic was used to develop the end-use models using data on urban users’ characteristics, their diurnal activities, and water use habits to estimate the demand characteristics of fixtures. The model may also facilitate the computation of pipe sizing in building water supply systems.
{"title":"User-based fuzzy end-use modeling of indoor urban residential water demand","authors":"Rohit D Mangalekar, K. Gumaste","doi":"10.1177/01436244221085916","DOIUrl":"https://doi.org/10.1177/01436244221085916","url":null,"abstract":"Stochastic models for estimating residential water demand use high-resolution field data consuming large costs and significant time. An attempt for the accurate estimation of water demand may result in its complex analytical model due to numerous factors affecting the water use event. Moreover, as the water supply system is always subjected to variations in demand, the accuracy of water demand estimation in its design can be side-lined. The water demand in residential buildings is mainly governed by the users’ characteristics and their daily schedule. In this view, the use of Fuzzy Logic can be advantageous to model the uncertainty in water demands. The presented study attempts to provide a methodology to estimate urban indoor residential water demand with the help of user-based end-use models in the absence of field data and generate various possible water demand patterns of fixtures. Usergroups were created for assuming spatial variations in water demand. Fuzzy Logic was used to develop the end-use models using data on urban users’ characteristics, their diurnal activities, and water use habits to estimate the demand characteristics of fixtures. The model may also facilitate the computation of pipe sizing in building water supply systems.","PeriodicalId":50724,"journal":{"name":"Building Services Engineering Research & Technology","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2022-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43169111","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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