Pub Date : 2014-06-06DOI: 10.1080/10789669.2014.929451
J. Wagner, M. Schäfer, A. Schlüter, Ludwig Harsch, J. Hesselbach, M. Rosano, Cheng-Xian Lin
Food and pharmaceutical refrigeration areas place significant demands on air temperature and air humidity control. This leads to high energy requirements on the HVAC system. In the majority of cases, the entire production hall is “over conditioned” with fresh air. However, very often the products are located in a small part of the overall production area (hall). From an energy efficiency and sustainability point of view, it makes sense to only air condition that area in which the products require refrigerated temperature control. One approach to reduce the refrigeration energy demand is to house the product in localized product cooling systems. In this study, localized product cooling systems are analyzed in order to identify the saving potentials associated with a localized HVAC refrigeration system. Experimental systems were built and evaluated. The simulation analysis highlighted that smaller localized refrigeration housing can reduce total energy demand by up to 65%.
{"title":"Reducing energy demand in production environment requiring refrigeration—A localized climatization approach","authors":"J. Wagner, M. Schäfer, A. Schlüter, Ludwig Harsch, J. Hesselbach, M. Rosano, Cheng-Xian Lin","doi":"10.1080/10789669.2014.929451","DOIUrl":"https://doi.org/10.1080/10789669.2014.929451","url":null,"abstract":"Food and pharmaceutical refrigeration areas place significant demands on air temperature and air humidity control. This leads to high energy requirements on the HVAC system. In the majority of cases, the entire production hall is “over conditioned” with fresh air. However, very often the products are located in a small part of the overall production area (hall). From an energy efficiency and sustainability point of view, it makes sense to only air condition that area in which the products require refrigerated temperature control. One approach to reduce the refrigeration energy demand is to house the product in localized product cooling systems. In this study, localized product cooling systems are analyzed in order to identify the saving potentials associated with a localized HVAC refrigeration system. Experimental systems were built and evaluated. The simulation analysis highlighted that smaller localized refrigeration housing can reduce total energy demand by up to 65%.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"59 1","pages":"628 - 642"},"PeriodicalIF":0.0,"publicationDate":"2014-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73027696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-06-04DOI: 10.1080/10789669.2014.917921
Junjun Hu, Oluwaseyi T. Ogunsola, Li Song, R. McPherson, Meijun Zhu, Y. Hong, Sheng Chen
The lack of standard procedures for filling climatic data has the potential to undermine design, monitoring, and control efforts aimed at climate-responsive building design, performance monitoring, and energy efficiency. This article addresses the challenge of long-term missing gaps in dry-bulb temperature data by examining three spatial methods, namely the inverse distance weighting (IDW) method, the spatial regression test (SRT) method, and the substitution with best match data (SSBM) method, as well as two temporal methods, namely the temporal regression test (TRT) method and the temporal substitution with best match data (TSBM) method. Using these methods, missing dry-bulb temperature data with long-term gaps, ranging from 1 to 60 days, are restored for use in building performance monitoring and analysis. Three one-year, hourly datasets were used to evaluate the performance of these approaches. Each method was applied to deal with artificial gaps which were generated randomly and represented different seasons of a year. In terms of the difference between estimated values and measured values, three evaluation indices, namely mean absolute error (MAE), root mean square error (RMSE), and standard error of bias (BIASSTD), were utilized. The comparison results show that spatial methods are better than temporal methods. The confidence level of the SRT method was further investigated by applying this method to existing data and missing data, and examining its performance. The results indicate that the uncertainty of the SRT method can be predicted and at least two neighboring stations are recommended when using it. This is the second part of the research results obtained through the ASHRAE 1413 research project (in press) with a focus on introducing gap-filling methods for long-term gaps in dry-bulb temperature.
{"title":"Restoration of missing dry-bulb temperature data with long-term gaps (up to 60 days) for use in building performance monitoring and analysis—Part II","authors":"Junjun Hu, Oluwaseyi T. Ogunsola, Li Song, R. McPherson, Meijun Zhu, Y. Hong, Sheng Chen","doi":"10.1080/10789669.2014.917921","DOIUrl":"https://doi.org/10.1080/10789669.2014.917921","url":null,"abstract":"The lack of standard procedures for filling climatic data has the potential to undermine design, monitoring, and control efforts aimed at climate-responsive building design, performance monitoring, and energy efficiency. This article addresses the challenge of long-term missing gaps in dry-bulb temperature data by examining three spatial methods, namely the inverse distance weighting (IDW) method, the spatial regression test (SRT) method, and the substitution with best match data (SSBM) method, as well as two temporal methods, namely the temporal regression test (TRT) method and the temporal substitution with best match data (TSBM) method. Using these methods, missing dry-bulb temperature data with long-term gaps, ranging from 1 to 60 days, are restored for use in building performance monitoring and analysis. Three one-year, hourly datasets were used to evaluate the performance of these approaches. Each method was applied to deal with artificial gaps which were generated randomly and represented different seasons of a year. In terms of the difference between estimated values and measured values, three evaluation indices, namely mean absolute error (MAE), root mean square error (RMSE), and standard error of bias (BIASSTD), were utilized. The comparison results show that spatial methods are better than temporal methods. The confidence level of the SRT method was further investigated by applying this method to existing data and missing data, and examining its performance. The results indicate that the uncertainty of the SRT method can be predicted and at least two neighboring stations are recommended when using it. This is the second part of the research results obtained through the ASHRAE 1413 research project (in press) with a focus on introducing gap-filling methods for long-term gaps in dry-bulb temperature.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"13 1","pages":"606 - 615"},"PeriodicalIF":0.0,"publicationDate":"2014-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76597091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-19DOI: 10.1080/10789669.2014.901713
E. Phillips
{"title":"Select Papers from the 7th International Conference on Cold Climate","authors":"E. Phillips","doi":"10.1080/10789669.2014.901713","DOIUrl":"https://doi.org/10.1080/10789669.2014.901713","url":null,"abstract":"","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"49 1","pages":"375 - 375"},"PeriodicalIF":0.0,"publicationDate":"2014-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86094064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-13DOI: 10.1080/10789669.2014.917934
H. Cheung, J. Braun
The market for variable-speed ductless heat pump (DHP) systems has grown in North America in recent years. However, the tools available for modeling their performance within building simulation programs have not kept pace. In general, simple empirical models are typically used for characterizing equipment performance for use in system simulation. However, unlike more conventional single-speed systems, DHPs have complicated control algorithms for managing electronic expansion valve opening, compressor speed, fan speed, and defrost operation. Very little work has been done in the development of empirical models that explain the impact of these characteristics on the performance of DHP systems. In this article, an empirical approach is introduced to model the heating and defrost performance of DHP systems under a wide range of conditions. The model incorporates separate relationships for performance associated with maximum, minimum, and intermediate (part-load) heating capacities. The defrost operation of the systems is also modeled empirically. The approach was tested on data from two DHP systems and the agreement is very good. The performance of the systems under different building loads was simulated and it is shown that the performance is highly dependent on the system control characteristics.
{"title":"Performance mapping for variable-speed ductless heat pump systems in heating and defrost operation","authors":"H. Cheung, J. Braun","doi":"10.1080/10789669.2014.917934","DOIUrl":"https://doi.org/10.1080/10789669.2014.917934","url":null,"abstract":"The market for variable-speed ductless heat pump (DHP) systems has grown in North America in recent years. However, the tools available for modeling their performance within building simulation programs have not kept pace. In general, simple empirical models are typically used for characterizing equipment performance for use in system simulation. However, unlike more conventional single-speed systems, DHPs have complicated control algorithms for managing electronic expansion valve opening, compressor speed, fan speed, and defrost operation. Very little work has been done in the development of empirical models that explain the impact of these characteristics on the performance of DHP systems. In this article, an empirical approach is introduced to model the heating and defrost performance of DHP systems under a wide range of conditions. The model incorporates separate relationships for performance associated with maximum, minimum, and intermediate (part-load) heating capacities. The defrost operation of the systems is also modeled empirically. The approach was tested on data from two DHP systems and the agreement is very good. The performance of the systems under different building loads was simulated and it is shown that the performance is highly dependent on the system control characteristics.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"1 1","pages":"545 - 558"},"PeriodicalIF":0.0,"publicationDate":"2014-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89142602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.887028
C. Craven, R. Garber-Slaght
Retrofitting walls with foam insulation is a common practice in residential construction to reduce heating demand; however, the implications of this practice for moisture control are less straightforward. Typically structures in cold climates have a polyethylene vapor retarder on the interior framing surface, therefore adding relatively water vapor impermeable exterior insulation greatly reduces the drying potential for the wall system. Furthermore, while condensation potential is reduced by the addition of exterior insulation, wood framing can be subject to a temperature and humidity regime more conducive to fungal growth relative to pre-retrofit conditions. To investigate the potential for exterior insulation retrofit strategies in subarctic climates to cause moisture accumulation in wood-framed structures, nine test wall sections were constructed using varying ratios of stud-fill and exterior insulation. The wall sections were tested in Fairbanks, Alaska, over two winters and were monitored for temperature, humidity, and wood moisture content. Test walls with less than two-thirds of the nominal wall R-value exterior to the framing performed poorly in terms of wood moisture content and relative humidity at the sheathing interior surface whether or not the test walls were equipped with vapor retarders. The findings are used to examine conventional moisture control frameworks.
{"title":"Exterior insulation envelope retrofits in cold climates: Implications for moisture control","authors":"C. Craven, R. Garber-Slaght","doi":"10.1080/10789669.2014.887028","DOIUrl":"https://doi.org/10.1080/10789669.2014.887028","url":null,"abstract":"Retrofitting walls with foam insulation is a common practice in residential construction to reduce heating demand; however, the implications of this practice for moisture control are less straightforward. Typically structures in cold climates have a polyethylene vapor retarder on the interior framing surface, therefore adding relatively water vapor impermeable exterior insulation greatly reduces the drying potential for the wall system. Furthermore, while condensation potential is reduced by the addition of exterior insulation, wood framing can be subject to a temperature and humidity regime more conducive to fungal growth relative to pre-retrofit conditions. To investigate the potential for exterior insulation retrofit strategies in subarctic climates to cause moisture accumulation in wood-framed structures, nine test wall sections were constructed using varying ratios of stud-fill and exterior insulation. The wall sections were tested in Fairbanks, Alaska, over two winters and were monitored for temperature, humidity, and wood moisture content. Test walls with less than two-thirds of the nominal wall R-value exterior to the framing performed poorly in terms of wood moisture content and relative humidity at the sheathing interior surface whether or not the test walls were equipped with vapor retarders. The findings are used to examine conventional moisture control frameworks.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"63 1","pages":"384 - 394"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79468682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.884380
Shichao Liu, A. Novoselac
Indoor particulate contaminants can be generated in many ways, commonly from human activities, infiltration of HVAC systems, or resuspension from indoor surfaces. Most of these sources are transient and generate nonuniform particle distribution in the space. This study used experimental and numerical methods to investigate the dispersion of three different particle sizes (0.7, 2.5, and 7 μm) emitted from typical source positions. A test room and simplified thermal manikins were employed to mimic a realistic indoor environment, and experimental data were compared with particle modeling using the Lagrangian method coupled with Reynolds averaged Navier-Stokes (RANS) and large eddy simulation (LES) computational fluid dynamics (CFD) turbulence models. Particle dispersion was studied for two ventilation patterns: buoyancy-driven ventilation and well-mixed ventilation. The results provided a comparison of Lagrangian-RANS particle modeling, Lagrangian-LES particle modeling, and experimental data considering nonuniform temporal and spatial particle concentrations. Experimental and modeling results were evaluated with three different metrics: peak normalized concentration at various locations, peak-concentration occurrence time, and mean exposure defined as the averaged concentration in the occupant's breathing zone. The results show that Lagrangian-LES more accurately predicts concentration fluctuation during particle emission. Considering long-term exposure, however, both methods show similar results.
{"title":"Lagrangian particle modeling in the indoor environment: A comparison of RANS and LES turbulence methods (RP-1512)","authors":"Shichao Liu, A. Novoselac","doi":"10.1080/10789669.2014.884380","DOIUrl":"https://doi.org/10.1080/10789669.2014.884380","url":null,"abstract":"Indoor particulate contaminants can be generated in many ways, commonly from human activities, infiltration of HVAC systems, or resuspension from indoor surfaces. Most of these sources are transient and generate nonuniform particle distribution in the space. This study used experimental and numerical methods to investigate the dispersion of three different particle sizes (0.7, 2.5, and 7 μm) emitted from typical source positions. A test room and simplified thermal manikins were employed to mimic a realistic indoor environment, and experimental data were compared with particle modeling using the Lagrangian method coupled with Reynolds averaged Navier-Stokes (RANS) and large eddy simulation (LES) computational fluid dynamics (CFD) turbulence models. Particle dispersion was studied for two ventilation patterns: buoyancy-driven ventilation and well-mixed ventilation. The results provided a comparison of Lagrangian-RANS particle modeling, Lagrangian-LES particle modeling, and experimental data considering nonuniform temporal and spatial particle concentrations. Experimental and modeling results were evaluated with three different metrics: peak normalized concentration at various locations, peak-concentration occurrence time, and mean exposure defined as the averaged concentration in the occupant's breathing zone. The results show that Lagrangian-LES more accurately predicts concentration fluctuation during particle emission. Considering long-term exposure, however, both methods show similar results.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"5 1","pages":"480 - 495"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79949393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.888368
Derek Whitehead, A. Frisque
The current industry standard method for estimating tall building entryway infiltration rates in cold climates is found in ASHRAE Handbook—Fundamentals (2013). This method was developed in ASHRAE Research Project (RP) 763 (Yuill 1996). In the comparison of an example calculation provided in RP-763 (Yuill 1996) and reproduced in 2013 ASHRAE Handbook Fundamentals (2013) with simulation results for the same example using various building configurations, the multi-node airflow analysis tool simulations consistently calculated significantly lower flow rates than predicted by the RP-763 (Yuill 1996) method (Whitehead and Frisque 2012). Addressing the large over-prediction of infiltration rates resulting from the estimation method currently published in the ASHRAE Handbook—Fundamentals (2013), this article proposes a new method to estimate this infiltration rate. The main difference of this new method (which we refer to as limiting area method [LAM]) is that it takes into account the smallest openings in the flow path limiting airflow. Comparison of results using the LAM to those from the previous simulations show that it is much closer to the more detailed simulation calculations, with estimates ranging from 92% to 134% of simulation results for the building examples considered.
{"title":"Estimating tall building infiltration at main entryway","authors":"Derek Whitehead, A. Frisque","doi":"10.1080/10789669.2014.888368","DOIUrl":"https://doi.org/10.1080/10789669.2014.888368","url":null,"abstract":"The current industry standard method for estimating tall building entryway infiltration rates in cold climates is found in ASHRAE Handbook—Fundamentals (2013). This method was developed in ASHRAE Research Project (RP) 763 (Yuill 1996). In the comparison of an example calculation provided in RP-763 (Yuill 1996) and reproduced in 2013 ASHRAE Handbook Fundamentals (2013) with simulation results for the same example using various building configurations, the multi-node airflow analysis tool simulations consistently calculated significantly lower flow rates than predicted by the RP-763 (Yuill 1996) method (Whitehead and Frisque 2012). Addressing the large over-prediction of infiltration rates resulting from the estimation method currently published in the ASHRAE Handbook—Fundamentals (2013), this article proposes a new method to estimate this infiltration rate. The main difference of this new method (which we refer to as limiting area method [LAM]) is that it takes into account the smallest openings in the flow path limiting airflow. Comparison of results using the LAM to those from the previous simulations show that it is much closer to the more detailed simulation calculations, with estimates ranging from 92% to 134% of simulation results for the building examples considered.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"10 1","pages":"395 - 403"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82042277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.882627
Song Li, Weixiong Wang, Qiang Liu, Xiaokuan Li
Blade passing frequency (BPF) noise is the dominating component of the flow induced noise of centrifugal fans. The numerical methods for BPF noise prediction, based on the computational aeroacoustics (CAA), have been published for decades. However, there are a couple of challenges for accurately predicting noise for industrial centrifugal fans. The first arises from the fact that the free field hypothesis, adopted in the numerical model, has not yet been carefully studied. The second challenge stems from the current criteria for which the prediction results are compared to the measurement data. Because the test conditions do not always satisfy the requirements of the numerical model, inaccurate predictions occasionally resulted. Therefore, since the prediction results may deviate largely from the test data, the applicability of these methods is severely limited.
{"title":"Validation of numerical prediction method of BPF noise for industrial centrifugal fans","authors":"Song Li, Weixiong Wang, Qiang Liu, Xiaokuan Li","doi":"10.1080/10789669.2014.882627","DOIUrl":"https://doi.org/10.1080/10789669.2014.882627","url":null,"abstract":"Blade passing frequency (BPF) noise is the dominating component of the flow induced noise of centrifugal fans. The numerical methods for BPF noise prediction, based on the computational aeroacoustics (CAA), have been published for decades. However, there are a couple of challenges for accurately predicting noise for industrial centrifugal fans. The first arises from the fact that the free field hypothesis, adopted in the numerical model, has not yet been carefully studied. The second challenge stems from the current criteria for which the prediction results are compared to the measurement data. Because the test conditions do not always satisfy the requirements of the numerical model, inaccurate predictions occasionally resulted. Therefore, since the prediction results may deviate largely from the test data, the applicability of these methods is severely limited.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"75 1","pages":"435 - 443"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80687349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.888367
H. Bagge, D. Johansson, Lotti Lindstrii
As requirements regarding energy efficiency are getting tougher, buildings in the arctic, as well as the rest of the world, need to be more energy efficient without compromising a good indoor climate. This article presents measured moisture supply and occupancy level in a Swedish arctic multi-family apartment block. Measurements were done over 1 year every 30 minutes in a building consisting of 51 apartments located in Kiruna, at latitude 67.9°. Averages and typical variations on different timescales, year and day, are presented for the different parameters, as well as correlations between the parameters; for example, moisture supply as a function of occupancy level. The results can be used when input data for simulations of energy use, moisture conditions and indoor climate are chosen, as well as a reference to compare measurements to during verifications. In energy efficient buildings, occupant behavior generally has an extensive impact on building performance, which means that the characteristics of behavior related parameters are important to be able to describe.
{"title":"Measured indoor hygrothermal conditions and occupancy levels in an arctic Swedish multi-family building","authors":"H. Bagge, D. Johansson, Lotti Lindstrii","doi":"10.1080/10789669.2014.888367","DOIUrl":"https://doi.org/10.1080/10789669.2014.888367","url":null,"abstract":"As requirements regarding energy efficiency are getting tougher, buildings in the arctic, as well as the rest of the world, need to be more energy efficient without compromising a good indoor climate. This article presents measured moisture supply and occupancy level in a Swedish arctic multi-family apartment block. Measurements were done over 1 year every 30 minutes in a building consisting of 51 apartments located in Kiruna, at latitude 67.9°. Averages and typical variations on different timescales, year and day, are presented for the different parameters, as well as correlations between the parameters; for example, moisture supply as a function of occupancy level. The results can be used when input data for simulations of energy use, moisture conditions and indoor climate are chosen, as well as a reference to compare measurements to during verifications. In energy efficient buildings, occupant behavior generally has an extensive impact on building performance, which means that the characteristics of behavior related parameters are important to be able to describe.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"6 1","pages":"376 - 383"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79190186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-05-09DOI: 10.1080/10789669.2014.882677
Zhuyang Han, W. Weng, Quanyi Huang
This article investigates the aerodynamic effects of human movement by experiment and numerical simulations. In the experiment, a life-size thermal manikin, a double-track orbit, and a trolley were used to realize human movement, and the velocity distribution of the induced airflow was measured. In the numerical simulations, dynamic meshing was used to simulate the human movement. The aerodynamic effects and flow fields under moving speeds of 0.5, 0.75, 1.0, 1.25, and 1.5 m/s were studied. The same timing relationship and tendency of the instantaneous velocity can be found between the measured and computed results, although the computed peak values are smaller than the measured ones. Apparent recirculation zones and vortices can be seen in the wake behind the human body in numerical simulations. The streamwise velocity profile and the structure of the wake depend on the profile of the human body and the moving speed. At each location, the nondimensional relative velocities of different moving speeds are substantially the same. The aerodynamic effects of human movements depend on the moving speed, moving distance, and spatial location. These results can be a good help for the studies on pollutant dispersion, control of air quality, and infectious diseases in indoor environment.
{"title":"Numerical and experimental investigation on the dynamic airflow of human movement in a full-scale cabin","authors":"Zhuyang Han, W. Weng, Quanyi Huang","doi":"10.1080/10789669.2014.882677","DOIUrl":"https://doi.org/10.1080/10789669.2014.882677","url":null,"abstract":"This article investigates the aerodynamic effects of human movement by experiment and numerical simulations. In the experiment, a life-size thermal manikin, a double-track orbit, and a trolley were used to realize human movement, and the velocity distribution of the induced airflow was measured. In the numerical simulations, dynamic meshing was used to simulate the human movement. The aerodynamic effects and flow fields under moving speeds of 0.5, 0.75, 1.0, 1.25, and 1.5 m/s were studied. The same timing relationship and tendency of the instantaneous velocity can be found between the measured and computed results, although the computed peak values are smaller than the measured ones. Apparent recirculation zones and vortices can be seen in the wake behind the human body in numerical simulations. The streamwise velocity profile and the structure of the wake depend on the profile of the human body and the moving speed. At each location, the nondimensional relative velocities of different moving speeds are substantially the same. The aerodynamic effects of human movements depend on the moving speed, moving distance, and spatial location. These results can be a good help for the studies on pollutant dispersion, control of air quality, and infectious diseases in indoor environment.","PeriodicalId":13238,"journal":{"name":"HVAC&R Research","volume":"28 1","pages":"444 - 457"},"PeriodicalIF":0.0,"publicationDate":"2014-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89371622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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：