International Journal of Ventilation最新文献

{"title":"A comparative analysis of potential aerosol exposure in a wide-body aircraft cabin using tracer gas and fluorescent particles","authors":"Seif Mahmoud, James Bennett, Byron Jones, Mohammad Hosni","doi":"10.1080/14733315.2023.2290920","DOIUrl":"https://doi.org/10.1080/14733315.2023.2290920","url":null,"abstract":"We compare two aerosol surrogate tracers in aircraft cabins for breathing and coughing sources: tracer gas collected in the ACER Boeing 767 mock-up and fluorescent particles collected in an actual ...","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"96 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138691584","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}

{"title":"A theoretical calculation method for critical air velocity to prevent methane draft pressure-caused airflow reversion based on oscillation theory","authors":"Zeqi Wu, Kai Wang, Huaitao Song, Kun Wang, Lin Shao","doi":"10.1080/14733315.2023.2282336","DOIUrl":"https://doi.org/10.1080/14733315.2023.2282336","url":null,"abstract":"Methane draft pressure is a secondary disaster for mine ventilation following coal and gas outbursts, which poses a long-term threat to coal mining and workers’ safety. To study the law of methane ...","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"222 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138532473","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}

{"title":"Impacts of horizontal and vertical louvers on the natural cross-ventilation performance of a generic building","authors":"Reza Rahimi, Rahim Hassanzadeh","doi":"10.1080/14733315.2023.2273148","DOIUrl":"https://doi.org/10.1080/14733315.2023.2273148","url":null,"abstract":"AbstractWind-based natural cross-ventilation is defined as a process in which fresh air is injected into a building via a high-pressure windward window and exhausts into the atmosphere through a low-pressure leeward window. There are several parameters that affect the natural ventilation performance, which should be considered in detail to reach the maximum air quality inside the buildings. In the present study, the effects of horizontal and vertical louvers on the wind-driven natural cross-ventilation performance of a generic building are assessed using computational fluid dynamics. In this regard, horizontal and vertical louvers with installation louver angles of 15°, 30°, and 45° are compared with each other and corresponding non-louver cases. Computations are carried out for three different free-wind speeds of 1, 2, and 3 m/s to show the impact of the external conditions on the natural ventilation of louvered cases. The obtained results revealed that under a low free-wind speed of 1 m/s, the minimum age of air and maximum air exchange efficiency occur for vertical louvers with an installation angle of 15°, while at moderate and high free-wind speeds of 2 and 3 m/s, the horizontal louvers with an installation angle of 15° provide the best condition for a generic building. HighlightsEffects of horizontal and vertical louvers on the wind-driven cross-ventilation were studied.At a free-wind speed of 1 m/s, the minimum age of air and maximum air exchange efficiency occur for vertical louver with α = 15°.At UH = 2 and 3 m/s, horizontal louver with α = 15° provides the best condition for a generic building.Keywords: Age of airair exchange efficiencycross-ventilationnatural ventilation Data availability statementData sharing is not applicable to this article as no new data were created or analyzed in this study.Disclosure statementNo potential conflict of interest was reported by the authors.Additional informationNotes on contributorsReza RahimiReza Rahimi is a Ph.D. candidate in Mechanical Engineering at Urmia University of Technology. His research interests include heat and mass transfer and numerical simulation.Rahim HassanzadehRahim Hassanzadeh is an associate professor of Mechanical Engineering at Urmia University of Technology. Her research focuses on wind and solar energy equipment, heat exchangers, and HVAC systems.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"2021 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135635479","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}

{"title":"Validation of simulated velocity distribution in isothermal mixing ventilation cases with particle streak tracking","authors":"Gerrid Brockmann, Anne Hartmann, Martin Kriegel","doi":"10.1080/14733315.2023.2263276","DOIUrl":"https://doi.org/10.1080/14733315.2023.2263276","url":null,"abstract":"AbstractThis is a validation study for the velocity distribution in mixing ventilation. Two different supply air diffusers a slot and a swirl diffuser form two different room airflows. For the swirl diffuser two different and for the slot diffuser five different exhaust positioning are tested numerically and experimentally. A comparison of the flow structure shows good agreement between simulation and experiment for six air changes per hour, but not for the lower air change rate of 1.5 per hour. The velocity deviations between experiment and simulation are higher for the swirl diffuser. These exist partly due to the experimental methodology, but also due to an overestimation of the supply air momentum. Thus, further sensitivity investigations are carried out for the swirl diffuser. The overestimation of the supply air momentum depends mainly on a geometric model error in the computational fluid dynamics simulation. A comparison of different turbulence models confirms the advantages of the RST elliptic blending turbulence model over the k-epsilon realizable model for the swirl diffuser case.HighlightsComparison between experimental and numerical velocity determinationFull-scale experimental data with PST-technologyTwo different supply air diffusers: slot and swirlValidation of different turbulence models including RSTCosine theorem-based method for comparison of the flow characteristicKeywords: Airflow characteristicairflow structureturbulence modelscomputational fluid dynamicsexperimental fluid dynamics Disclosure statementNo potential conflict of interest was reported by the authors.Data availability statementThe data that support the findings of this study are openly available in DepositOnce of the Technische Univeristät Berlin at https://doi.org/10.14279/depositonce-18189.Notes1 Trox GmbH, LVS/125/G1/P1-RAL9005-70%.2 Trox GmbH, VDW-Q-Z-V/500x24/P1-RAL9005-70%.3 Trox GmbH, VSD35-1-AK-M-L/600x98/C1/P1-RAL9005-70%.4 The photo is taken from a nonisothermal setup. The cylindrical heat dummies are not part of the isothermal measurements.5 Developed and manufactured by the Hermann-Rietschel-Institut, Technische Universität Berlin.6 CANON EOS 5D.7 National Institutes of Health.8 Dantec Dynamics, accuracy: ±2 % for 0–1 m s−1, ±5 % for 1–5 m s−1.9 Siemens Digital Industries Software.10 The subsequent aim of the research project is to evaluate the ventilation effectiveness, therefore, the age of the air is considered as a quality characteristic in the grid independency study.11 Python Software Foundation.12 Pillow is a PIL fork by Alex Clark and Contributors.Additional informationFundingThis work was funded by the German Federal Ministry for Economic Affairs and Climate Protection (BMWK) under the IGF funding code 20440 N. The authors assume responsibility for the content of this publication.Notes on contributorsGerrid BrockmannGerrid Brockmann is an engineering scientist at the Hermann-Rietschel-Institut of the Technische Universität Berlin and is worki","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135732326","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}

{"title":"Simulation of backflow during the dynamic containment of airlocks","authors":"Brahim Mohammedi, Athmane Gheziel, Nacim Mellel, M’hamed Salhi","doi":"10.1080/14733315.2023.2260668","DOIUrl":"https://doi.org/10.1080/14733315.2023.2260668","url":null,"abstract":"","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135925869","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}

{"title":"Experimental study on air extraction performance of novel rooftop natural ventilators","authors":"Kwan Ouyang, Tzeng-Yuan Chen, Weijun Mao","doi":"10.1080/14733315.2023.2251316","DOIUrl":"https://doi.org/10.1080/14733315.2023.2251316","url":null,"abstract":"","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"13 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75607056","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}

{"title":"Guest editorial: Ventilation challenges in a changing world - Selected papers from the 42nd AIVC Conference, 5–6 October 2022","authors":"A. Janssens, Maria Kapsalaki","doi":"10.1080/14733315.2023.2224685","DOIUrl":"https://doi.org/10.1080/14733315.2023.2224685","url":null,"abstract":"","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"4 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78361793","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}

{"title":"Evaluation of thermal resilience to overheating for an educational building in future heatwave scenarios","authors":"A. Sengupta, H. Breesch, D. Al Assaad, M. Steeman","doi":"10.1080/14733315.2023.2218424","DOIUrl":"https://doi.org/10.1080/14733315.2023.2218424","url":null,"abstract":"Airtight and highly insulated buildings are subjected to overheating risks, even in moderate climates, due to unforeseeable events like frequent heatwaves and power outages. Educational buildings share a major portion of building stocks and a large percentage of the energy is expended in maintaining thermal comfort in these buildings. Overheating risks in educational buildings can lead to heat-stress and negatively impact the health conditions and also cognitive performance of the occupants. In the light of increasing severity and longevity of heat waves in future climate scenarios, and associated power outages occurring during the heatwaves, measures to reduce overheating risk while limiting the cooling energy is gaining importance. Since the performance of existing buildings are not guaranteed during events like heatwaves, power outages, it is crucial for these buildings to be resilient to overheating. (Building) resilience is a method to deal with these uncertainties and is stated as “an ability of the building to withstand disruptions; and to maintain the capacity to adapt, learn and transform.” The focus of this paper is to evaluate thermal resilience for two test lecture equipped with low-energy cooling strategies like natural night ventilation (NNV) and indirect evaporative cooling (IEC) rooms, by dynamic Building Energy Simulations (BES). To assess the thermal resilience to overheating three different heatwaves (HW) files ( intense, severe, and longest) for 3 future scenarios (1) Historical (2010-2020), (2) mid-term (2041 -2060) and (3) long-term (2081-2100) and a 24h power outage (PO)scenario was simulated. Benchmarking was done with a base case- Typical Meteorological year(TMY) with no power outage. The heatwave files were developed adopting the methodology proposed by the 'Weather Data Task Force’ of International Energy Agency Energy in Buildings and Communities Programme (IEA EBC) Annex 80 “Resilient Cooling of Buildings”. This study shows, IEC has high to moderate recovery capacity in TMY period and low recovery capacity in HW period, for a power outage of 24 h. Recovery capacity is low during HW period, especially during an intense and longer HW period when outdoor temperature influences the cooling capacity of the IEC. The results also demonstrates the impact of the thermal mass on the resilience to overheating. Passive survivability assessment indicates, the lecture room with lighter thermal mass does not violate 30℃ threshold during a power outage in TMY period and additionally,. recovers faster (11% times faster) from peak temperature compared to lecture room with heavy thermal mass. There is a steep increase in unmet degree hours (occupied hours above24℃ threshold) during HW compared to TMY period. This paper gives a directive towards assessment of resilience to overheating and also points out the gap in the existing indicators to assess the resilience.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"120 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89230853","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}

{"title":"Air leakage detection in building façades by combining lock-in thermography with blower excitation","authors":"Benedikt Kölsch, J. Pernpeintner, Björn Schiricke, E. Lüpfert","doi":"10.1080/14733315.2023.2198791","DOIUrl":"https://doi.org/10.1080/14733315.2023.2198791","url":null,"abstract":"Abstract Air leakage in building envelopes is responsible for a large portion of the building’s heating and cooling requirements. Therefore, fast and reliable detection of leaks is crucial for improving energy efficiency. This paper presents a new approach to determining air leakages in a building’s envelope from the outside, combining lock-in thermography and thermal excitation by a blower door system. The blower creates a periodic overpressure within the building, inducing periodic temperature variations of the surfaces near the leaks on the outside surface, the façade. With the temperature variations excited at a known frequency, Fourier transforms of the time-series of the thermal images at the excitation frequency result in amplitude and phase images highlighting the areas affected by leaks. Periodic excitation and detection by an IR camera is known as lock-in thermography and is widely used to characterise semiconductor devices and in non-destructive testing. Excitation is usually achieved by optical, electrical, or mechanical energy input. For this work, measurements of outside façades have been performed with three excitation cycles of a period of 40 s at a 75 Pa pressure difference, leading to a total measurement time of only 2 min. Measurements have been performed with air temperature differences of 5 to 7 K at highly variable conditions of irradiance, wind, and cloud cover. The measurements show higher detection quality and less impact from changing ambient conditions than the state-of-the-art differential infrared thermography measurements. With the method highlighting the variations in the amplitude image only at the excitation frequency, variations caused by environmental effects are filtered out. A temperature difference as low as a few Kelvin is therefore sufficient, and large façades can be examined from the outside. This amplitude image is already clearer than an image created with differential thermography. A further reduction of unwanted artefacts in the image is demonstrated using phase-weighing of the amplitude by scalar product.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"16 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73289641","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}

{"title":"The effect of airflow guiding components on effective ventilation rates in single-sided ventilation applications","authors":"Nima Najafi Ziarani, M. Cook, Paul D. O'Sullivan","doi":"10.1080/14733315.2023.2198793","DOIUrl":"https://doi.org/10.1080/14733315.2023.2198793","url":null,"abstract":"Abstract Wind-driven single-sided ventilation (SSV) is present in many existing buildings across Europe, and with new near-zero energy building (NZEB) regulations for the refurbishment of the existing building stock, its attractiveness as a noninvasive, low-energy solution is set to continue. As a strategy, however, in addition to its air change rate capacity, the distribution of fresh air is an important evaluation criterion for its performance. Airflow guiding components located in the external opening that enhance the effectiveness of the wind-driven flow in ventilating the occupied zone could improve the quality of indoor environments. To our knowledge, the literature is sparse on the practical implications for ventilation when adopting guiding components such as louvres, an increasingly popular approach. In the present study, the performance of wind-dominant SSV was simulated using RNG and RSM CFD models, with and without louvres at three building orientations, for example, windward, parallel and leeward. The purpose of this study was to investigate whether louvres installed in the opening would improve both the effective ventilation rate and the penetration depth of the flow into the indoor space. The performance of SSV was evaluated using the age of air and interpreting the secondary air circulation inside the room affected by louvres. As a result of these investigations, a newly configured airflow guiding component was designed and compared to the other cases. Results show louvres can play a crucial role in controlling the secondary air circulation inside the room, and they could either improve or worsen the performance of SSV in terms of air-exchange efficiency. It was shown that in most cases, if louvres were the cause of incremental changes in turbulent intensity within the indoor space, then they are effective as an air-exchange efficiency improvement strategy.","PeriodicalId":55613,"journal":{"name":"International Journal of Ventilation","volume":"38 1","pages":""},"PeriodicalIF":1.5,"publicationDate":"2023-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89334956","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}