Experimental and Computational Multiphase Flow最新文献

{"title":"Spatial distributions of airborne transmission risk on commuter buses: Numerical case study using computational fluid and particle dynamics with computer-simulated persons.","authors":"Sung-Jun Yoo,&nbsp;Akira Kurokawa,&nbsp;Kazuhiko Matsunaga,&nbsp;Kazuhide Ito","doi":"10.1007/s42757-022-0146-6","DOIUrl":"10.1007/s42757-022-0146-6","url":null,"abstract":"<p><p>Commuter buses have a high passenger density relative to the interior cabin volume, and it is difficult to maintain a physical/social distance in terms of airborne transmission control. Therefore, it is important to quantitatively investigate the impact of ventilation and air-conditioning in the cabin on the airborne transmission risk for passengers. In this study, comprehensive coupled numerical simulations using computational fluid and particle dynamics (CFPD) and computer-simulated persons (CSPs) were performed to investigate the heterogeneous spatial distribution of the airborne transmission risk in a commuter bus environment under two types of layouts of the ventilation system and two types of passenger densities. Through a series of particle transmission analysis and infection risk assessment in this study, it was revealed that the layout of the supply inlet/exhaust outlet openings of a heating, ventilation, and air-conditioning (HVAC) system has a significant impact on the particle dispersion characteristics inside the bus cabin, and higher infection risks were observed near the single exhaust outlet in the case of higher passenger density. The integrated analysis of CFPD and CSPs in a commuter bus cabin revealed that the airborne transmission risk formed significant heterogeneous spatial distributions, and the changes in air-conditioning conditions had a certain impact on the risk.</p>","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 3","pages":"304-318"},"PeriodicalIF":6.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9912221/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9607641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A computational analysis on the impact of multilevel laryngotracheal stenosis on airflow and drug particle dynamics in the upper airway.","authors":"Raluca E Gosman,&nbsp;Ryan M Sicard,&nbsp;Seth M Cohen,&nbsp;Dennis O Frank-Ito","doi":"10.1007/s42757-022-0151-9","DOIUrl":"10.1007/s42757-022-0151-9","url":null,"abstract":"<p><p>Laryngotracheal stenosis (LTS) is a type of airway narrowing that is frequently caused by intubation-related trauma. LTS can occur at one or multiple locations in the larynx and/or trachea. This study characterizes airflow dynamics and drug delivery in patients with multilevel stenosis. Two subjects with multilevel stenosis (S1 = glottis + trachea, S2 = glottis + subglottis) and one normal subject were retrospectively selected. Computed tomography scans were used to create subject-specific upper airway models. Computational fluid dynamics modeling was used to simulate airflow at inhalation pressures of 10, 25, and 40 Pa, and orally inhaled drug transport with particle velocities of 1, 5, and 10 m/s, and particle size range of 100 nm-40 µm. Subjects had increased airflow velocity and resistance at stenosis with decreased cross-sectional area (CSA): S1 had the smallest CSA at trachea (0.23 cm²) and resistance = 0.3 Pa·s/mL; S2 had the smallest CSA at glottis (0.44 cm²), and resistance = 0.16 Pa·s/mL. S1 maximal stenotic deposition was 4.15% at trachea; S2 maximal deposition was 2.28% at glottis. Particles of 11-20 µm had the greatest deposition, 13.25% (S1-trachea) and 7.81% (S2-subglottis). Results showed differences in airway resistance and drug delivery between subjects with LTS. Less than 4.2% of orally inhaled particles deposited at stenosis. Particle sizes with most stenotic deposition were 11-20 µm and may not represent typical particle sizes emitted by current-use inhalers.</p>","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 3","pages":"235-246"},"PeriodicalIF":6.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10024600/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9612289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying strategies to minimize aerosol dispersion in dental clinics.","authors":"Shamudra Dey,&nbsp;Maryam Tunio,&nbsp;Louis C Boryc,&nbsp;Brian D Hodgson,&nbsp;Guilherme J M Garcia","doi":"10.1007/s42757-022-0157-3","DOIUrl":"10.1007/s42757-022-0157-3","url":null,"abstract":"<p><p>Many dental procedures are aerosol-generating and pose a risk for the spread of airborne diseases, including COVID-19. Several aerosol mitigation strategies are available to reduce aerosol dispersion in dental clinics, such as increasing room ventilation and using extra-oral suction devices and high-efficiency particulate air (HEPA) filtration units. However, many questions remain unanswered, including what the optimal device flow rate is and how long after a patient exits the room it is safe to start treatment of the next patient. This study used computational fluid dynamics (CFD) to quantify the effectiveness of room ventilation, an HEPA filtration unit, and two extra-oral suction devices to reduce aerosols in a dental clinic. Aerosol concentration was quantified as the particulate matter under 10 µm (PM₁₀) using the particle size distribution generated during dental drilling. The simulations considered a 15 min procedure followed by a 30 min resting period. The efficiency of aerosol mitigation strategies was quantified by the scrubbing time, defined as the amount of time required to remove 95% of the aerosol released during the dental procedure. When no aerosol mitigation strategy was applied, PM₁₀ reached 30 µg/m³ after 15 min of dental drilling, and then declined gradually to 0.2 µg/m³ at the end of the resting period. The scrubbing time decreased from 20 to 5 min when the room ventilation increased from 6.3 to 18 air changes per hour (ACH), and decreased from 10 to 1 min when the flow rate of the HEPA filtration unit increased from 8 to 20 ACH. The CFD simulations also predicted that the extra-oral suction devices would capture 100% of the particles emanating from the patient's mouth for device flow rates above 400 L/min. In summary, this study demonstrates that aerosol mitigation strategies can effectively reduce aerosol concentrations in dental clinics, which is expected to reduce the risk of spreading COVID-19 and other airborne diseases.</p>","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 3","pages":"290-303"},"PeriodicalIF":6.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10042415/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9612287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Message from the Guest Editor of the 18th Multiphase Flow Conference Special Issue.","authors":"Dirk Lucas","doi":"10.1007/s42757-022-0154-6","DOIUrl":"10.1007/s42757-022-0154-6","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 4","pages":"331-332"},"PeriodicalIF":6.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10202046/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9545701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of transport, deposition, and resultant immune response of nasal spray vaccine droplets using a CFPD-HCD model in a 6-year-old upper airway geometry to potentially prevent COVID-19.","authors":"Hamideh Hayati, Yu Feng, Xiaole Chen, Emily Kolewe, Catherine Fromen","doi":"10.1007/s42757-022-0145-7","DOIUrl":"10.1007/s42757-022-0145-7","url":null,"abstract":"<p><p>This study focuses on the transport, deposition, and triggered immune response of intranasal vaccine droplets to the angiotensin-converting-enzyme-2-rich region, i.e., the olfactory region (OR), in the nasal cavity of a 6-year-old female to possibly prevent corona virus disease 19 (COVID-19). To investigate how administration strategy can influence nasal vaccine efficiency, a validated multi-scale model, i.e., computational fluid-particle dynamics (CFPD) and host-cell dynamics (HCD) model, was employed. Droplet deposition fraction, size change, residence time, and the area percentage of OR covered by the vaccine droplets, and triggered immune system response were predicted with different spray cone angles, initial droplet velocities, and compositions. Numerical results indicate that droplet initial velocity and composition have negligible influences on the vaccine delivery efficiency to OR. In contrast, the spray cone angle can significantly impact the vaccine delivery efficiency. The triggered immunity was not significantly influenced by the administration investigated in this study due to the low percentage of OR area covered by the droplets. To enhance the effectiveness of the intranasal vaccine to prevent COVID-19 infection, it is necessary to optimize the vaccine formulation and administration strategy so that the vaccine droplets can cover more epithelial cells in OR to minimize the number of available receptors for SARS-CoV-2.</p>","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 3","pages":"272-289"},"PeriodicalIF":4.2,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9851113/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9616664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Message from the Guest Editor of the SCONA 2022 Meeting Special Issue.","authors":"Kiao Inthavong","doi":"10.1007/s42757-022-0147-5","DOIUrl":"10.1007/s42757-022-0147-5","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 3","pages":"233-234"},"PeriodicalIF":4.2,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10250167/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9653344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modelling of free bubble growth with Interface Capturing Computational Fluid Dynamics","authors":"G. Giustini, R. Issa","doi":"10.1007/s42757-022-0139-5","DOIUrl":"https://doi.org/10.1007/s42757-022-0139-5","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 1","pages":"357 - 364"},"PeriodicalIF":6.5,"publicationDate":"2022-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41773439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 review of recent study on the characteristics and applications of pebble flows in nuclear engineering","authors":"N. Gui, Shengyao Jiang, Xingtuan Yang, J. Tu","doi":"10.1007/s42757-022-0140-z","DOIUrl":"https://doi.org/10.1007/s42757-022-0140-z","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"4 1","pages":"339 - 349"},"PeriodicalIF":6.5,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48594738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of the effect of nasopharynx airway obstruction on the transport and deposition of nanoparticles in nasal airways","authors":"Q. Sun, Jingliang Dong, Ya Zhang, L. Tian, J. Tu","doi":"10.1007/s42757-022-0143-9","DOIUrl":"https://doi.org/10.1007/s42757-022-0143-9","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"4 1","pages":"399 - 408"},"PeriodicalIF":6.5,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41377284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of two-group void fraction covariance correlations on interfacial drag predictions for two-fluid model calculations in large diameter pipes","authors":"Alexander Swearingen, Sean Drewry, J. Schlegel, T. Hibiki","doi":"10.1007/s42757-022-0138-6","DOIUrl":"https://doi.org/10.1007/s42757-022-0138-6","url":null,"abstract":"","PeriodicalId":53125,"journal":{"name":"Experimental and Computational Multiphase Flow","volume":"5 1","pages":"221-231"},"PeriodicalIF":6.5,"publicationDate":"2022-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45093695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}