Pub Date : 2023-10-18DOI: 10.1080/23744731.2023.2266349
Alicia R. Urrutia, Stanislaw P. Stawicki, Charles N. Kimble, Kathryn C. Worrilow
Many facility acquired infection (FAI) causing pathogens are airborne and controlling them is critical to preventing illness. An advanced air purification technology (AAPT) was designed to inactivate the genetic material of pathogens and remediate volatile organic compounds (VOCs). This study explores the effect of the AAPT on critical metrics in multiple healthcare settings. The AAPT was installed in the heating, ventilation, and air conditioning (HVAC) ductwork of a hospital’s medical surgical floor (ACH-MSF), a second hospital’s post-anesthesia care unit (PACU), intensive care unit (ICU) and medical surgical (MS) unit, and in a senior living facility’s (SLF) memory support unit. In all installations, the control area(s) were protected only by high efficiency particulate air (HEPA) filtration. The measured airborne fungal levels, airborne and surface bacterial levels, and VOC levels decreased with installation of AAPT. The AAPT removed infectious airborne pathogens and reduced surface pathogens and VOCs. The ACH-MSF and SLF protected by the AAPT documented improved clinical and economic metrics including a 39.5% decrease in patient length of stay, 23% in cost savings improvement, and a 39.6% decrease in FAIs. The current findings support the hypothesis that indoor environmental quality impacts wellness and has potential applications to diverse indoor environments.
{"title":"The Clinical and Environmental Effects of an Advanced Air Purification Technology in Multiple Healthcare Settings","authors":"Alicia R. Urrutia, Stanislaw P. Stawicki, Charles N. Kimble, Kathryn C. Worrilow","doi":"10.1080/23744731.2023.2266349","DOIUrl":"https://doi.org/10.1080/23744731.2023.2266349","url":null,"abstract":"Many facility acquired infection (FAI) causing pathogens are airborne and controlling them is critical to preventing illness. An advanced air purification technology (AAPT) was designed to inactivate the genetic material of pathogens and remediate volatile organic compounds (VOCs). This study explores the effect of the AAPT on critical metrics in multiple healthcare settings. The AAPT was installed in the heating, ventilation, and air conditioning (HVAC) ductwork of a hospital’s medical surgical floor (ACH-MSF), a second hospital’s post-anesthesia care unit (PACU), intensive care unit (ICU) and medical surgical (MS) unit, and in a senior living facility’s (SLF) memory support unit. In all installations, the control area(s) were protected only by high efficiency particulate air (HEPA) filtration. The measured airborne fungal levels, airborne and surface bacterial levels, and VOC levels decreased with installation of AAPT. The AAPT removed infectious airborne pathogens and reduced surface pathogens and VOCs. The ACH-MSF and SLF protected by the AAPT documented improved clinical and economic metrics including a 39.5% decrease in patient length of stay, 23% in cost savings improvement, and a 39.6% decrease in FAIs. The current findings support the hypothesis that indoor environmental quality impacts wellness and has potential applications to diverse indoor environments.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135823705","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 : 2023-10-18DOI: 10.1080/23744731.2023.2261808
Karen Fenaughty, Danny S. Parker, Joshua Butzbaugh, Carlos Colon
AbstractHeat pump water heaters (HPWH) are a proven method of reducing water heating energy use over prevailing electric resistance systems (ERWH). Both technologies lend themselves to enhanced control for peak load reduction. Laboratory tests were conducted in Central Florida using the CTA-2045 standard to evaluate load shifting strategies with connected water heaters. Four HPWHs from three manufacturers, including two different tank volumes were tested alongside an ERWH in a garage-like environment. Tests aimed to shift energy use away from utility peak load periods to off-peak times when excess renewable energy resources are available. Two load-shifting strategies were shown effective, Shed and Critical Peak, with variation by manufacturer. Beyond draw volume, other factors influenced HPWH load shifting:Florida winter conditions, which increase the energy used per draw, provided the greatest challenges to complete load shift. Inlet water temperature had a large impact on the success of load reduction. Ground temperatures in which water pipes were buried largely determined inlet water temperatures.HPWH efficiency setting: Heat pump water heaters often default to a “hybrid” mode that may use some electric resistance heat to minimize risk of running out of hot water. Operational mode can impact load shifting potential. BackgroundHeat pump water heaters (HPWH) are a well demonstrated technology to significantly reduce electricity consumption for meeting household hot water needs. A variety of monitored projects around the U.S. have shown savings of 50-70%, reflected by operational coefficient of performance (COP), relative to conventional electric resistance storage water heaters (Colon et al. 2016; Shapiro and Puttagunta 2016; Willem, Lin, and Lekov 2017). Within the last decade, systems have shown even higher operational COPs from improved compressors and other design enhancements. (Willem, Lin, and Lekov 2017).Beyond the ability to save water heating electricity, HPWHs can also cut peak demand. Many large utility providers in the southeast already have demand response and load management programs (Butzbaugh and Winiarski 2020) and may find value in promoting grid-connected HPWHs capable of load shifting if demonstrated to provide superior load control. This can be thought of as the ability to not only control utility-coincident peak loads, but also to alter the water heating electrical demand profile in a significant manner (e.g., alter electric load profile shape to consume a greater amount of daytime utility scale renewable energy). Current HPWHs and some ERWHs available for purchase are compatible with CTA-2045-A protocol (ANSI/CTA 2018). This protocol has demonstrated electric demand flexibility in the Northwest to provide a utility the ability to control when an appliance draws power from the grid (Metzger et al. 2018). And Carew et al (2018) have detailed simulation studies of load shifting with HPWHs. Other related work evaluating HPWHs
热泵热水器(HPWH)是一种行之有效的方法，减少水加热能源的使用超过现行的电阻系统(ERWH)。这两种技术都可以增强对峰值负载降低的控制。使用CTA-2045标准在佛罗里达州中部进行了实验室测试，以评估连接热水器的负荷转移策略。来自三家制造商的四个hpwh，包括两个不同的油箱容量，与一个ERWH一起在类似车库的环境中进行了测试。测试的目的是将能源使用从公用事业高峰负荷时期转移到可再生能源过剩的非高峰时段。两种负载转移策略显示有效，棚和临界峰值，不同的制造商的变化。除了抽水量之外，其他因素也影响着HPWH的负荷转移:佛罗里达州的冬季条件增加了每次抽水量的能耗，为完成负荷转移提供了最大的挑战。进水温度对减载的成功与否有很大的影响。水管所在的地温很大程度上决定了进水温度。HPWH效率设置:热泵热水器通常默认为“混合”模式，可能会使用一些电阻热来最小化热水耗尽的风险。操作模式会影响负荷转移潜力。热泵热水器(HPWH)是一项已得到充分证明的技术，可显著减少电力消耗，以满足家庭热水需求。通过运行性能系数(COP)，美国各地的各种监测项目显示，与传统电阻储水式热水器相比，节省了50-70%的成本(Colon等人，2016;Shapiro and Puttagunta 2016;Willem, Lin, and Lekov 2017)。在过去的十年中，系统通过改进压缩机和其他设计增强，显示出更高的运行cop。(Willem, Lin, and Lekov 2017)。除了节约水、加热和电力的能力之外，HPWHs还可以减少高峰需求。东南部的许多大型公用事业供应商已经有了需求响应和负荷管理计划(Butzbaugh和Winiarski 2020)，如果证明能够提供卓越的负荷控制，可能会发现推广能够转移负荷的并网HPWHs的价值。这不仅可以被认为是控制公用事业同步峰值负荷的能力，而且还可以以显着的方式改变水加热电力需求剖面(例如，改变电力负荷剖面形状以消耗更多的白天公用事业规模可再生能源)。目前可购买的HPWHs和一些ERWHs与CTA-2045- a协议(ANSI/CTA 2018)兼容。该协议展示了西北地区电力需求的灵活性，为公用事业公司提供了控制设备何时从电网获取电力的能力(Metzger et al. 2018)。Carew等人(2018)对HPWHs的负载转移进行了详细的模拟研究。其他评估HPWHs的相关工作是围绕加州Title 24标准制定进行的(Hendron et al. 2020)。一项多户负荷转移HPWH研究完成了详细的建模，显示了更高的年千瓦时使用量(11-18%)，但在北加州气候的现场监测研究中，峰值能源平均减少了68% (Hoeschele和Haile 2022)。然而，这是第一次进行全面实验室测试的评估。CTA-2045协议标准化了通信模块和“智能”设备之间的硬件接口，以及电力供应商与连接设备通信时使用的语言。制造商根据工程参数和水箱内的水温概况来确定热水器如何响应控制命令，因此在协议的实施中可能存在差异。免责声明作为对作者和研究人员的服务，我们提供了这个版本的已接受的手稿(AM)。在最终出版版本记录(VoR)之前，将对该手稿进行编辑、排版和审查。在制作和印前，可能会发现可能影响内容的错误，所有适用于期刊的法律免责声明也与这些版本有关。注1在UEF测试程序中，HPWHs的测试条件为67.5°F(19.7°C)干球空气温度(+/- 2.5°F(1.4°C))和50%相对湿度(+/- 2)，进水温度为58°F(14.4°C)(+/- 2°F(1.1°C))。
{"title":"Detailed evaluation of electric demand load shifting potential of heat pump water heaters in a hot humid climate","authors":"Karen Fenaughty, Danny S. Parker, Joshua Butzbaugh, Carlos Colon","doi":"10.1080/23744731.2023.2261808","DOIUrl":"https://doi.org/10.1080/23744731.2023.2261808","url":null,"abstract":"AbstractHeat pump water heaters (HPWH) are a proven method of reducing water heating energy use over prevailing electric resistance systems (ERWH). Both technologies lend themselves to enhanced control for peak load reduction. Laboratory tests were conducted in Central Florida using the CTA-2045 standard to evaluate load shifting strategies with connected water heaters. Four HPWHs from three manufacturers, including two different tank volumes were tested alongside an ERWH in a garage-like environment. Tests aimed to shift energy use away from utility peak load periods to off-peak times when excess renewable energy resources are available. Two load-shifting strategies were shown effective, Shed and Critical Peak, with variation by manufacturer. Beyond draw volume, other factors influenced HPWH load shifting:Florida winter conditions, which increase the energy used per draw, provided the greatest challenges to complete load shift. Inlet water temperature had a large impact on the success of load reduction. Ground temperatures in which water pipes were buried largely determined inlet water temperatures.HPWH efficiency setting: Heat pump water heaters often default to a “hybrid” mode that may use some electric resistance heat to minimize risk of running out of hot water. Operational mode can impact load shifting potential. BackgroundHeat pump water heaters (HPWH) are a well demonstrated technology to significantly reduce electricity consumption for meeting household hot water needs. A variety of monitored projects around the U.S. have shown savings of 50-70%, reflected by operational coefficient of performance (COP), relative to conventional electric resistance storage water heaters (Colon et al. 2016; Shapiro and Puttagunta 2016; Willem, Lin, and Lekov 2017). Within the last decade, systems have shown even higher operational COPs from improved compressors and other design enhancements. (Willem, Lin, and Lekov 2017).Beyond the ability to save water heating electricity, HPWHs can also cut peak demand. Many large utility providers in the southeast already have demand response and load management programs (Butzbaugh and Winiarski 2020) and may find value in promoting grid-connected HPWHs capable of load shifting if demonstrated to provide superior load control. This can be thought of as the ability to not only control utility-coincident peak loads, but also to alter the water heating electrical demand profile in a significant manner (e.g., alter electric load profile shape to consume a greater amount of daytime utility scale renewable energy). Current HPWHs and some ERWHs available for purchase are compatible with CTA-2045-A protocol (ANSI/CTA 2018). This protocol has demonstrated electric demand flexibility in the Northwest to provide a utility the ability to control when an appliance draws power from the grid (Metzger et al. 2018). And Carew et al (2018) have detailed simulation studies of load shifting with HPWHs. Other related work evaluating HPWHs ","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135824018","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}
Abstract:Over the last decade, the global fight against climate change through electrification has led to an increase in research on building heating, ventilation, and air conditioning (HVAC) systems that utilize intelligent control algorithms to provide demand-side grid service while also maintaining the thermal comfort of building occupants. As the pivotal point between building electricity consumption and indoor thermal comfort, high-efficiency electrical vapor-compression heat pumps are at the center of these emerging studies, and various grid-interactive and occupant-comfort control algorithms have been developed for them. The impact of these algorithms on heat pump operation and performance when subjected to different weather conditions, building loads, and grid requests calls for investigation and verification via experimental testing with actual heat pumps integrated with real-time building and grid responses. This study introduces a Water-Source Heat Pump (WSHP) Hardware-in-The-Loop (HIL) Test Facility that is the first of its kind. This testbed utilizes a 2-ton variable speed water-to-air heat pump that is capable of interacting with a virtual environment currently comprised of an EnergyPlus (E+) building simulation, an agent-based occupant behavioral model, and a single U-tube ground-loop heat exchanger (GLHE) model. Detailed descriptions of the testbed’s physical design and operation, virtual environement, as well as their mutual communication is provided. An uncertainty analysis is also performed under manufacturer specified heating and cooling design conditions. This analysis shows that the total load across the WSHP’s demand side heat exchanger, i.e., the sum of its latent and sensible components, can be measured with a relative uncertainty of ± 10.4 % and ± 3.6 % in cooling and heating mode respectively. The WSHP’s coefficient of performance (COP) can be measured with relative uncertainties of ± 10.4 % in cooling mode, and ± 3.7% in heating mode. A preliminary 24-hour experimental demonstration is then performed utilizing the DOE prototype small commercial office building model in E+. The simulation takes place in Atlanta, GA on the date of 08/26/15 from 12:00 AM to 11:59 PM using TMY3 weather data. . The results from this demonstration show that over the course of this experiment the simulated outputs of zone dry-bulb temperature, zone humidity ratio, and WSHP inlet water temperature can be tracked by testbed emulators up to a root mean squared error (RMSE) of ± 0.27 °C, ± 0.376 g/kg, and ± 0.85 °C respectively. The WSHP’s dynamic behavioral characteristics and performance are also captured, and correspond well with the authors’ previous understanding of heat pump efficiency as a function of evaporator and condenser fluid inlet conditions respectively.Keywords: Water-Source Heat PumpHardware-in-the-LoopExperimentalDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copye
{"title":"Performance Assessment of a Real Water Source Heat Pump within a Hardware-in-the-Loop (HIL) Testing Environment","authors":"Caleb Calfa, Zhiyao Yang, Yicheng Li, Zhelun Chen, Zheng O’Neill, Jin Wen","doi":"10.1080/23744731.2023.2261810","DOIUrl":"https://doi.org/10.1080/23744731.2023.2261810","url":null,"abstract":"Abstract:Over the last decade, the global fight against climate change through electrification has led to an increase in research on building heating, ventilation, and air conditioning (HVAC) systems that utilize intelligent control algorithms to provide demand-side grid service while also maintaining the thermal comfort of building occupants. As the pivotal point between building electricity consumption and indoor thermal comfort, high-efficiency electrical vapor-compression heat pumps are at the center of these emerging studies, and various grid-interactive and occupant-comfort control algorithms have been developed for them. The impact of these algorithms on heat pump operation and performance when subjected to different weather conditions, building loads, and grid requests calls for investigation and verification via experimental testing with actual heat pumps integrated with real-time building and grid responses. This study introduces a Water-Source Heat Pump (WSHP) Hardware-in-The-Loop (HIL) Test Facility that is the first of its kind. This testbed utilizes a 2-ton variable speed water-to-air heat pump that is capable of interacting with a virtual environment currently comprised of an EnergyPlus (E+) building simulation, an agent-based occupant behavioral model, and a single U-tube ground-loop heat exchanger (GLHE) model. Detailed descriptions of the testbed’s physical design and operation, virtual environement, as well as their mutual communication is provided. An uncertainty analysis is also performed under manufacturer specified heating and cooling design conditions. This analysis shows that the total load across the WSHP’s demand side heat exchanger, i.e., the sum of its latent and sensible components, can be measured with a relative uncertainty of ± 10.4 % and ± 3.6 % in cooling and heating mode respectively. The WSHP’s coefficient of performance (COP) can be measured with relative uncertainties of ± 10.4 % in cooling mode, and ± 3.7% in heating mode. A preliminary 24-hour experimental demonstration is then performed utilizing the DOE prototype small commercial office building model in E+. The simulation takes place in Atlanta, GA on the date of 08/26/15 from 12:00 AM to 11:59 PM using TMY3 weather data. . The results from this demonstration show that over the course of this experiment the simulated outputs of zone dry-bulb temperature, zone humidity ratio, and WSHP inlet water temperature can be tracked by testbed emulators up to a root mean squared error (RMSE) of ± 0.27 °C, ± 0.376 g/kg, and ± 0.85 °C respectively. The WSHP’s dynamic behavioral characteristics and performance are also captured, and correspond well with the authors’ previous understanding of heat pump efficiency as a function of evaporator and condenser fluid inlet conditions respectively.Keywords: Water-Source Heat PumpHardware-in-the-LoopExperimentalDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copye","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135896000","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 : 2023-09-29DOI: 10.1080/23744731.2023.2263324
Eliot Crowe, Yimin Chen, Hayden Reeve, David Yuill, Amir Ebrahimifakhar, Yuxuan Chen, Lucas Troup, Amanda Smith, Jessica Granderson
Commercial building HVAC systems experience many sensing, mechanical, and control-related faults that increase energy consumption and impact occupant comfort. Fault detection & diagnostics (FDD) software has been demonstrated to identify and help diagnose these types of faults. Several studies have demonstrated FDD energy savings potential, but there is limited empirical data characterizing the quantity and type of faults reported by FDD tools. This paper presents results of an FDD fault reporting study, employing multi-year monitoring data for over 60,000 pieces of HVAC equipment, covering over 90 fault types, and using new metrics that we developed to characterize fault prevalence. Study results offer an unprecedented accounting of the quantity of faults reported, the most commonly occurring faults, and fault persistence. We find that 21 air handling unit (AHU) faults were reported on 20% or more AHUs in our dataset, and 18 AHU faults persisted for more than 20% of the time period covered by the data. On any given day, 40% of AHUs and 30% of air terminal units saw a reported fault of some kind. Based on in-depth analysis of these results we provide recommendations for building operators, FDD software developers, and researchers to enable more efficient commercial building operation.
{"title":"Empirical Analysis of the Prevalence of HVAC Faults in Commercial Buildings","authors":"Eliot Crowe, Yimin Chen, Hayden Reeve, David Yuill, Amir Ebrahimifakhar, Yuxuan Chen, Lucas Troup, Amanda Smith, Jessica Granderson","doi":"10.1080/23744731.2023.2263324","DOIUrl":"https://doi.org/10.1080/23744731.2023.2263324","url":null,"abstract":"Commercial building HVAC systems experience many sensing, mechanical, and control-related faults that increase energy consumption and impact occupant comfort. Fault detection & diagnostics (FDD) software has been demonstrated to identify and help diagnose these types of faults. Several studies have demonstrated FDD energy savings potential, but there is limited empirical data characterizing the quantity and type of faults reported by FDD tools. This paper presents results of an FDD fault reporting study, employing multi-year monitoring data for over 60,000 pieces of HVAC equipment, covering over 90 fault types, and using new metrics that we developed to characterize fault prevalence. Study results offer an unprecedented accounting of the quantity of faults reported, the most commonly occurring faults, and fault persistence. We find that 21 air handling unit (AHU) faults were reported on 20% or more AHUs in our dataset, and 18 AHU faults persisted for more than 20% of the time period covered by the data. On any given day, 40% of AHUs and 30% of air terminal units saw a reported fault of some kind. Based on in-depth analysis of these results we provide recommendations for building operators, FDD software developers, and researchers to enable more efficient commercial building operation.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135246733","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 : 2023-09-27DOI: 10.1080/23744731.2023.2261807
Kevin Autelitano, Michele Bolognini, Enrico de Angelis, Lorenzo Fagiano, Marco Scaioni
AbstractThe adoption of Unmanned Aerial Vehicles for energy efficiency assessment is a promising technique. Although there are some interesting ideas to automate the process, most of the operations are still done manually. An integrated methodology is presented to identify maintenance needs from both RGB and IR images collected with a commercial drone. The real building selected as case study is reconstructed in a 3D environment through Structure from Motion, while the infrared information is integrated and properly scaled on it to obtain a 3D point cloud model that provides, for each point: (i) information about its position in the space (ii) external surface temperature measured during data gathering phase. The point cloud is then segmented into the different sides of the envelope to identify each part of the façade and compared with a model that reconstructs the expected conditions of the building. This procedure enables the development of an automated pipeline to identify defects and failures in a building envelope and to suggest corrective actionsDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.
摘要采用无人机进行能源效率评估是一项很有前途的技术。尽管有一些有趣的想法可以实现流程自动化，但大多数操作仍然是手动完成的。提出了一种综合方法，从商用无人机收集的RGB和IR图像中识别维护需求。选取作为案例研究的真实建筑，通过Structure from Motion在三维环境中进行重建，同时对红外信息进行整合和适当缩放，得到三维点云模型，该模型为每个点提供:(i)其在空间中的位置信息(ii)数据采集阶段测量的外表面温度。然后将点云分割到围护结构的不同侧面，以识别立面的每个部分，并与重建建筑物预期条件的模型进行比较。此程序使开发自动化管道能够识别建筑围护结构中的缺陷和故障，并建议纠正措施。免责声明作为对作者和研究人员的服务，我们提供此版本的已接受手稿(AM)。在最终出版版本记录(VoR)之前，将对该手稿进行编辑、排版和审查。在制作和印前，可能会发现可能影响内容的错误，所有适用于期刊的法律免责声明也与这些版本有关。
{"title":"On the Use of Vision-based Drone Application to Building Digitalization, Diagnostics and Energy Efficiency Assessment <sup>*</sup>","authors":"Kevin Autelitano, Michele Bolognini, Enrico de Angelis, Lorenzo Fagiano, Marco Scaioni","doi":"10.1080/23744731.2023.2261807","DOIUrl":"https://doi.org/10.1080/23744731.2023.2261807","url":null,"abstract":"AbstractThe adoption of Unmanned Aerial Vehicles for energy efficiency assessment is a promising technique. Although there are some interesting ideas to automate the process, most of the operations are still done manually. An integrated methodology is presented to identify maintenance needs from both RGB and IR images collected with a commercial drone. The real building selected as case study is reconstructed in a 3D environment through Structure from Motion, while the infrared information is integrated and properly scaled on it to obtain a 3D point cloud model that provides, for each point: (i) information about its position in the space (ii) external surface temperature measured during data gathering phase. The point cloud is then segmented into the different sides of the envelope to identify each part of the façade and compared with a model that reconstructs the expected conditions of the building. This procedure enables the development of an automated pipeline to identify defects and failures in a building envelope and to suggest corrective actionsDisclaimerAs a service to authors and researchers we are providing this version of an accepted manuscript (AM). Copyediting, typesetting, and review of the resulting proofs will be undertaken on this manuscript before final publication of the Version of Record (VoR). During production and pre-press, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal relate to these versions also.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135535478","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 : 2023-09-01DOI: 10.1080/23744731.2023.2253084
Yuande Dai, Ziyu Wang, Jiahuan Wu, Chao Xu
The understanding of two-phase flow and heat transfer characteristics of refrigerants in tubes is important for guiding the design and optimization of heat exchangers. Based on the volume of fluid (VOF) multiphase model, this paper established a numerical model of R1234ze(E)/R152a (mass ratio of 0.4/0.6) flow boiling heat transfer in a horizontal smooth copper tube with an inner diameter of 6 mm and a length of 900 mm. The distribution of vapor volume fraction is obtained, and the influence of mass flux, heat flux, saturation temperature, and vapor quality on heat transfer coefficient (HTC) are studied. Bubble flow, plug flow, stratified flow, and wavy flow can be observed during the whole process and the fluid temperature increases along the tube. Local and time-averaged heat transfer coefficients and temperature distribution along the axial direction were studied. And the results indicate that the HTC decreases first and then increases with the augmentation of mass flux while increasing with the rise of heat flux. In addition, the HTC rises along with saturation temperature and decreases along with vapor quality. The largest related standard deviation between the simulation value and the testing data is 6.31%. Thus, the numerical simulation has a high level of accuracy.
{"title":"Numerical Simulation on Flow Boiling Heat Transfer of R1234ze(E)/R152a in a Horizontal Smooth Tube","authors":"Yuande Dai, Ziyu Wang, Jiahuan Wu, Chao Xu","doi":"10.1080/23744731.2023.2253084","DOIUrl":"https://doi.org/10.1080/23744731.2023.2253084","url":null,"abstract":"The understanding of two-phase flow and heat transfer characteristics of refrigerants in tubes is important for guiding the design and optimization of heat exchangers. Based on the volume of fluid (VOF) multiphase model, this paper established a numerical model of R1234ze(E)/R152a (mass ratio of 0.4/0.6) flow boiling heat transfer in a horizontal smooth copper tube with an inner diameter of 6 mm and a length of 900 mm. The distribution of vapor volume fraction is obtained, and the influence of mass flux, heat flux, saturation temperature, and vapor quality on heat transfer coefficient (HTC) are studied. Bubble flow, plug flow, stratified flow, and wavy flow can be observed during the whole process and the fluid temperature increases along the tube. Local and time-averaged heat transfer coefficients and temperature distribution along the axial direction were studied. And the results indicate that the HTC decreases first and then increases with the augmentation of mass flux while increasing with the rise of heat flux. In addition, the HTC rises along with saturation temperature and decreases along with vapor quality. The largest related standard deviation between the simulation value and the testing data is 6.31%. Thus, the numerical simulation has a high level of accuracy.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49315173","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 : 2023-08-31DOI: 10.1080/23744731.2023.2253087
D. Villa, J. Quiroz
Renewable microgrids are sustainable, resilient solutions to mitigate and adapt to climate change. Making electric loads nearly 100% available (i.e., power remains on) during outages increases cost. Near 100% availability is required when human life or high-cost assets are involved, but availability can be reduced for less consequential loads leading to lower costs. This study analyses costs for photo-voltaic and lithium-ion battery microgrids with availability ranging from 0–99%. We develop a methodology to analyse three Puerto Rican coastal communities. We consider power outage effects for hurricanes, earthquakes, and everyday outages. The results show cost versus availability from 0–99%. There is 27–31% cost reduction at 80% availability in comparison to 99% availability. A regression model of microgrid availability versus three ratios: 1) the annual generation to demand ratio, 2) storage to interruption energy ratio, and 3) peak storage to load ratio produced a coefficient of determination of 0.99949 with 70% of the data used for training and 30% for testing. The results can therefore be extended to other coastal Puerto Rican communities of varying sizes that have ratios within the ranges analysed in this study. This can empower decision makers to rapidly analyse designs that have availabilities well below 100%.
{"title":"Reducing Microgrid Availability to Reduce Costs for Coastal Puerto Rican Communities","authors":"D. Villa, J. Quiroz","doi":"10.1080/23744731.2023.2253087","DOIUrl":"https://doi.org/10.1080/23744731.2023.2253087","url":null,"abstract":"Renewable microgrids are sustainable, resilient solutions to mitigate and adapt to climate change. Making electric loads nearly 100% available (i.e., power remains on) during outages increases cost. Near 100% availability is required when human life or high-cost assets are involved, but availability can be reduced for less consequential loads leading to lower costs. This study analyses costs for photo-voltaic and lithium-ion battery microgrids with availability ranging from 0–99%. We develop a methodology to analyse three Puerto Rican coastal communities. We consider power outage effects for hurricanes, earthquakes, and everyday outages. The results show cost versus availability from 0–99%. There is 27–31% cost reduction at 80% availability in comparison to 99% availability. A regression model of microgrid availability versus three ratios: 1) the annual generation to demand ratio, 2) storage to interruption energy ratio, and 3) peak storage to load ratio produced a coefficient of determination of 0.99949 with 70% of the data used for training and 30% for testing. The results can therefore be extended to other coastal Puerto Rican communities of varying sizes that have ratios within the ranges analysed in this study. This can empower decision makers to rapidly analyse designs that have availabilities well below 100%.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43926115","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 : 2023-08-30DOI: 10.1080/23744731.2023.2247938
Christian Rosdahl, B. Bernhardsson, Bryan A. Eisenhower
The performance of HVAC equipment, including chillers, is continuing to be pushed to theoretical limits, which impacts the necessity for advanced control logic to operate them efficiently and robustly. At the same time, their architectures are becoming more complex; many systems have multiple compressors, expansion devices, evaporators, circuits, or other elements that challenge control design and resulting performance. In order to maintain respectful controlled speed of response, stability, and robustness, controllers are becoming more complex, including the move from thermostatic control, to proportional integrator (PI), and to multiple-input multiple-output (MIMO) controllers. Model-based control design works well for their synthesis, while having accurate models for numerous product variants is unrealistic, often leading to very conservative designs. To address this, we propose and demonstrate a learning-based control tuner that supports the design of MIMO decoupling PI controllers using online information to adapt controller coefficients from an initial guess during commissioning or operation. The approach is tested on a physics-based model of a water-cooled screw chiller. The method is able to find a controller that performs better than a nominal controller (two single PI controllers) in terms of decreasing deviations from the operating point during disturbances while still following reference changes.
{"title":"Model-Free MIMO Control Tuning of a Chiller Process Using Reinforcement Learning","authors":"Christian Rosdahl, B. Bernhardsson, Bryan A. Eisenhower","doi":"10.1080/23744731.2023.2247938","DOIUrl":"https://doi.org/10.1080/23744731.2023.2247938","url":null,"abstract":"The performance of HVAC equipment, including chillers, is continuing to be pushed to theoretical limits, which impacts the necessity for advanced control logic to operate them efficiently and robustly. At the same time, their architectures are becoming more complex; many systems have multiple compressors, expansion devices, evaporators, circuits, or other elements that challenge control design and resulting performance. In order to maintain respectful controlled speed of response, stability, and robustness, controllers are becoming more complex, including the move from thermostatic control, to proportional integrator (PI), and to multiple-input multiple-output (MIMO) controllers. Model-based control design works well for their synthesis, while having accurate models for numerous product variants is unrealistic, often leading to very conservative designs. To address this, we propose and demonstrate a learning-based control tuner that supports the design of MIMO decoupling PI controllers using online information to adapt controller coefficients from an initial guess during commissioning or operation. The approach is tested on a physics-based model of a water-cooled screw chiller. The method is able to find a controller that performs better than a nominal controller (two single PI controllers) in terms of decreasing deviations from the operating point during disturbances while still following reference changes.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45019010","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 : 2023-08-29DOI: 10.1080/23744731.2023.2253085
S. Kujak, Morgan Leehey
This paper examines the findings of highly accelerated life tests (HALT), conducted according to ASHRAE Standard 97 sealed glass tube methodology for R-123 like, R-134a like and R-410A/R-404A like lower global warming potential (GWP) alternatives. Additionally, possible chemical breakdown pathways are reviewed for the new haloolefin refrigerants. Note, compositions for the following blends are shown as percent by weight. For R-123 like refrigerants, R-1336mzz(Z), R-1336mzz(E), R-514A (74.7% R-1336mzz(Z)/25.3% R-1130(E)), R-1233zd(E), and R-1224yd(Z) were examined with and without lubricants. R-1233zd(E) and R-1224yd(Z) were evaluated with mineral oil and the rest were evaluated with polyalkylene glycol (PAG), polyolester (POE) and polyvinyl ether (PVE) lubricants. For R-134a like refrigerants, R-1234ze(E), R-450A (42% R-134a/58% R-1234ze(E)), R-515B (91.1% R-1234ze(E)/8.9% R-227ea), R-1234yf, R-513A (56% R-1234yf/44% R-134a), and R-516A (77.5% R-1234yf/8.5% R-134a/14.0% R-152a) were examined with and without PAG, POE, and PVE lubricants. For R-410A/R-404A like, R-454B (68.9% R-32/31.1% R-1234yf), R-454C (21.5% R-32/78.5% R-1234yf), R-455A (3.0% R-744/21.5% R-32/75.5% R-1234yf), and R-468A (3.5% R-1132a/21.5% R-32/75.0% R-1234yf) were also examined with PAG, POE and PVE lubricants. R-466A (49% R-32/11.5% R-125/39.5% CF3I) was part of this study but will not be covered since it does not contain a haloolefin component.
{"title":"Chemical Stability Investigation of Haloolefin Refrigerants and Their Blends with Lubricants","authors":"S. Kujak, Morgan Leehey","doi":"10.1080/23744731.2023.2253085","DOIUrl":"https://doi.org/10.1080/23744731.2023.2253085","url":null,"abstract":"This paper examines the findings of highly accelerated life tests (HALT), conducted according to ASHRAE Standard 97 sealed glass tube methodology for R-123 like, R-134a like and R-410A/R-404A like lower global warming potential (GWP) alternatives. Additionally, possible chemical breakdown pathways are reviewed for the new haloolefin refrigerants. Note, compositions for the following blends are shown as percent by weight. For R-123 like refrigerants, R-1336mzz(Z), R-1336mzz(E), R-514A (74.7% R-1336mzz(Z)/25.3% R-1130(E)), R-1233zd(E), and R-1224yd(Z) were examined with and without lubricants. R-1233zd(E) and R-1224yd(Z) were evaluated with mineral oil and the rest were evaluated with polyalkylene glycol (PAG), polyolester (POE) and polyvinyl ether (PVE) lubricants. For R-134a like refrigerants, R-1234ze(E), R-450A (42% R-134a/58% R-1234ze(E)), R-515B (91.1% R-1234ze(E)/8.9% R-227ea), R-1234yf, R-513A (56% R-1234yf/44% R-134a), and R-516A (77.5% R-1234yf/8.5% R-134a/14.0% R-152a) were examined with and without PAG, POE, and PVE lubricants. For R-410A/R-404A like, R-454B (68.9% R-32/31.1% R-1234yf), R-454C (21.5% R-32/78.5% R-1234yf), R-455A (3.0% R-744/21.5% R-32/75.5% R-1234yf), and R-468A (3.5% R-1132a/21.5% R-32/75.0% R-1234yf) were also examined with PAG, POE and PVE lubricants. R-466A (49% R-32/11.5% R-125/39.5% CF3I) was part of this study but will not be covered since it does not contain a haloolefin component.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43631629","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 : 2023-08-29DOI: 10.1080/23744731.2023.2253089
Mahsa Salimi, L. De Nardo, V. Carvelli
Thermal energy storage (TES) based on phase change materials (PCM) is an effective strategy to reduce energy consumption in buildings. The efficient implementation of TES in building through PCMs, requires modification of their thermal performance, appropriate design and evaluation of their thermal and economic efficiency. One major challenge in the application of PCMs is the selection of high-performance and environmental-friendly supporting materials to overcome the most critical drawback of PCMs (solid-to-liquid transition and resulting leakage). This review focuses on expanded clay (EC) lightweight aggregate (LWA), as one of the promising supporting materials for development of form-stabilized PCM (FSPCM) in the lightweight concrete (LWC) industry. The large specific surface area and porous structure of expanded clay can maintain considerable amount of PCM. In addition, mechanical properties and compatibility with various PCMs make EC a suitable carrier. A detailed review of available researches is presented to elucidate the properties of PCMs embedded in EC for thermally efficient cement-based concrete. Various combinations of EC with the most used PCMs, thermal and mechanical properties of matrices containing PCM-EC, strategies to improve the efficiency of PCM performance, and finally the impact of PCM-EC based concretes on the thermal comfort of buildings are critically summarized.
{"title":"Phase change materials embedded in expanded clay aggregates to develop energy storage concrete: a review","authors":"Mahsa Salimi, L. De Nardo, V. Carvelli","doi":"10.1080/23744731.2023.2253089","DOIUrl":"https://doi.org/10.1080/23744731.2023.2253089","url":null,"abstract":"Thermal energy storage (TES) based on phase change materials (PCM) is an effective strategy to reduce energy consumption in buildings. The efficient implementation of TES in building through PCMs, requires modification of their thermal performance, appropriate design and evaluation of their thermal and economic efficiency. One major challenge in the application of PCMs is the selection of high-performance and environmental-friendly supporting materials to overcome the most critical drawback of PCMs (solid-to-liquid transition and resulting leakage). This review focuses on expanded clay (EC) lightweight aggregate (LWA), as one of the promising supporting materials for development of form-stabilized PCM (FSPCM) in the lightweight concrete (LWC) industry. The large specific surface area and porous structure of expanded clay can maintain considerable amount of PCM. In addition, mechanical properties and compatibility with various PCMs make EC a suitable carrier. A detailed review of available researches is presented to elucidate the properties of PCMs embedded in EC for thermally efficient cement-based concrete. Various combinations of EC with the most used PCMs, thermal and mechanical properties of matrices containing PCM-EC, strategies to improve the efficiency of PCM performance, and finally the impact of PCM-EC based concretes on the thermal comfort of buildings are critically summarized.","PeriodicalId":21556,"journal":{"name":"Science and Technology for the Built Environment","volume":" ","pages":""},"PeriodicalIF":1.9,"publicationDate":"2023-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46133587","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：