Pub Date : 2026-01-22DOI: 10.1146/annurev-fluid-100224-111138
Isabelle Cantat, Savinien Pertant, Christophe Raufaste, Emmanuelle Rio
Soap films and bubbles are inherently unstable systems that evolve over time. Their thickness is primarily governed by the competition between capillary and viscous forces. The presence of surfactants introduces Marangoni stresses, which limit interfacial extension and significantly increase film lifetime. While the bulk flow is typically well-described by a simple Poiseuille profile between the two interfaces, the interfacial dynamics can induce complex behaviors, even in the simple case of horizontal film drainage, which is used as a paradigmatic example in this review. The interfacial velocity is dictated by the thickness gradients and by the interfacial rheology, which, in many practical cases, reduces to the condition of an incompressible interface. This simplified framework allows for analytical predictions and scaling laws in axisymmetric flows. It is also consistent with the spontaneous symmetry breaking that may be observed in horizontal films—a phenomenon associated with the marginal regeneration process, which remains only partially understood. This review presents the most elementary theoretical frameworks capable of capturing the essential features of these flows and provides quantitative comparisons with available experimental data.
{"title":"Capillary Drainage in Horizontal Soap Films: Theoretical Review and Experimental Illustrations","authors":"Isabelle Cantat, Savinien Pertant, Christophe Raufaste, Emmanuelle Rio","doi":"10.1146/annurev-fluid-100224-111138","DOIUrl":"https://doi.org/10.1146/annurev-fluid-100224-111138","url":null,"abstract":"Soap films and bubbles are inherently unstable systems that evolve over time. Their thickness is primarily governed by the competition between capillary and viscous forces. The presence of surfactants introduces Marangoni stresses, which limit interfacial extension and significantly increase film lifetime. While the bulk flow is typically well-described by a simple Poiseuille profile between the two interfaces, the interfacial dynamics can induce complex behaviors, even in the simple case of horizontal film drainage, which is used as a paradigmatic example in this review. The interfacial velocity is dictated by the thickness gradients and by the interfacial rheology, which, in many practical cases, reduces to the condition of an incompressible interface. This simplified framework allows for analytical predictions and scaling laws in axisymmetric flows. It is also consistent with the spontaneous symmetry breaking that may be observed in horizontal films—a phenomenon associated with the marginal regeneration process, which remains only partially understood. This review presents the most elementary theoretical frameworks capable of capturing the essential features of these flows and provides quantitative comparisons with available experimental data.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"119 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146109705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2026-01-22DOI: 10.1146/annurev-fluid-112723-053105
Andrew W. Woods
Decarbonization of buildings is one of the main challenges for the energy transition. In particular, the provision of heating, cooling, and ventilation to maintain a comfortable and healthy interior environment can be very energy intensive. Three approaches to help with the decarbonization of buildings are ( a ) upgrading the building envelope, especially the insulation, to reduce heat flow to or from the exterior; ( b ) improving the efficiency of the heating or cooling system, including the design and operation of ventilation flows; and ( c ) decarbonization of the heating and cooling systems, typically through electrification using heat pumps, and possibly the development of heat networks and interseasonal heat storage. This review touches on different elements of these challenges, mainly those related to ventilation, exploring some of the complexities of the fluid mechanics involved.
{"title":"Fluid Mechanics for Green Buildings","authors":"Andrew W. Woods","doi":"10.1146/annurev-fluid-112723-053105","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112723-053105","url":null,"abstract":"Decarbonization of buildings is one of the main challenges for the energy transition. In particular, the provision of heating, cooling, and ventilation to maintain a comfortable and healthy interior environment can be very energy intensive. Three approaches to help with the decarbonization of buildings are ( <jats:italic>a</jats:italic> ) upgrading the building envelope, especially the insulation, to reduce heat flow to or from the exterior; ( <jats:italic>b</jats:italic> ) improving the efficiency of the heating or cooling system, including the design and operation of ventilation flows; and ( <jats:italic>c</jats:italic> ) decarbonization of the heating and cooling systems, typically through electrification using heat pumps, and possibly the development of heat networks and interseasonal heat storage. This review touches on different elements of these challenges, mainly those related to ventilation, exploring some of the complexities of the fluid mechanics involved.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"16 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2026-01-22DOI: 10.1146/annurev-fluid-112723-062216
Tirtha Banerjee
Characterizing the physical and dynamic meteorology of wildland fires has obvious socioeconomic importance and is necessary to develop not only firefighting but also mitigation strategies such as prescribed burns and effective fuel management practices such as forest thinning. However, despite significant progress over a century, there are shortcomings in our understanding of the physical processes governing wildland fire behavior. Although some research progress has been made in understanding how fires spread on grasslands, several aspects of fire behavior within the forest canopy environment are still not well-understood. This review is an attempt to organize the fluid mechanics of the mass, momentum, and energy transfer during wildland fire events through the lens of vegetation canopy turbulence. The structure, organization, and progress of the flame front and the buoyant plume through the canopy are shown to be intricately related to the coherent structures associated with fire–vegetation–atmosphere interaction, and potential future research directions are identified.
{"title":"The Role of Canopy Turbulence in Wildland Fire Behavior","authors":"Tirtha Banerjee","doi":"10.1146/annurev-fluid-112723-062216","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112723-062216","url":null,"abstract":"Characterizing the physical and dynamic meteorology of wildland fires has obvious socioeconomic importance and is necessary to develop not only firefighting but also mitigation strategies such as prescribed burns and effective fuel management practices such as forest thinning. However, despite significant progress over a century, there are shortcomings in our understanding of the physical processes governing wildland fire behavior. Although some research progress has been made in understanding how fires spread on grasslands, several aspects of fire behavior within the forest canopy environment are still not well-understood. This review is an attempt to organize the fluid mechanics of the mass, momentum, and energy transfer during wildland fire events through the lens of vegetation canopy turbulence. The structure, organization, and progress of the flame front and the buoyant plume through the canopy are shown to be intricately related to the coherent structures associated with fire–vegetation–atmosphere interaction, and potential future research directions are identified.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"8 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2026-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146110156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-03DOI: 10.1146/annurev-fluid-112723-052727
Zhangli Peng, Annie Viallat, Yuan-Nan Young
The squeezing of blood cells and vesicles through narrow constrictions, such as splenic slits, pulmonary capillaries, vascular endothelial gaps, and microfluidic channels, is crucial in physiology and biotechnology, with fluid mechanics playing a central role. The diverse geometries of these constrictions, the associated flow conditions, and the unique mechanical properties of cells and vesicles create a rich subject in fluid mechanics emerging from nonlinear dynamics of fluid–structure interactions involving both lubrication and Marangoni flows. Advances in microfluidics, video microscopy, and computational modeling have enabled investigations into these complex processes. This review surveys the key features and approaches, recent prominent studies, and unresolved challenges related to these processes, offering insights for researchers across biomechanics, biomedical engineering, biological physics, hematology, physiology, and applied mathematics.
{"title":"Fluid Mechanics of Blood Cells and Vesicles Squeezing Through Narrow Constrictions","authors":"Zhangli Peng, Annie Viallat, Yuan-Nan Young","doi":"10.1146/annurev-fluid-112723-052727","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112723-052727","url":null,"abstract":"The squeezing of blood cells and vesicles through narrow constrictions, such as splenic slits, pulmonary capillaries, vascular endothelial gaps, and microfluidic channels, is crucial in physiology and biotechnology, with fluid mechanics playing a central role. The diverse geometries of these constrictions, the associated flow conditions, and the unique mechanical properties of cells and vesicles create a rich subject in fluid mechanics emerging from nonlinear dynamics of fluid–structure interactions involving both lubrication and Marangoni flows. Advances in microfluidics, video microscopy, and computational modeling have enabled investigations into these complex processes. This review surveys the key features and approaches, recent prominent studies, and unresolved challenges related to these processes, offering insights for researchers across biomechanics, biomedical engineering, biological physics, hematology, physiology, and applied mathematics.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"99 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145215609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-03DOI: 10.1146/annurev-fluid-100224-111013
Alban Sauret, Tyler R. Ray, Brett G. Compton
Direct-ink writing (DIW) has rapidly become a versatile 3D fabrication method due to its ability to deposit a wide range of complex fluids into customizable 3D geometries. This review highlights key fundamental fluid mechanics and soft matter challenges across the different stages of the DIW printing process. The rheology of fluids and suspensions governs the flow behavior through narrow nozzles, posing questions about extrudability, confined flow dynamics, and clogging mechanisms. Downstream, the formation and deposition of extruded filaments involve extensional flows and potential instabilities, while postdeposition dynamics introduces complexities related to yield stress and structural stability. These stages are inherently interdependent, as optimizing material composition without considering filament stability risks compromising the final structure. As DIW applications expand through advanced ink formulations, developing fundamental fluid mechanics frameworks is essential to replace trial-and-error approaches with predictive design methodologies to enable more precise control over and reliability of the printing process.
{"title":"Fluid Mechanics Challenges in Direct-Ink-Writing Additive Manufacturing","authors":"Alban Sauret, Tyler R. Ray, Brett G. Compton","doi":"10.1146/annurev-fluid-100224-111013","DOIUrl":"https://doi.org/10.1146/annurev-fluid-100224-111013","url":null,"abstract":"Direct-ink writing (DIW) has rapidly become a versatile 3D fabrication method due to its ability to deposit a wide range of complex fluids into customizable 3D geometries. This review highlights key fundamental fluid mechanics and soft matter challenges across the different stages of the DIW printing process. The rheology of fluids and suspensions governs the flow behavior through narrow nozzles, posing questions about extrudability, confined flow dynamics, and clogging mechanisms. Downstream, the formation and deposition of extruded filaments involve extensional flows and potential instabilities, while postdeposition dynamics introduces complexities related to yield stress and structural stability. These stages are inherently interdependent, as optimizing material composition without considering filament stability risks compromising the final structure. As DIW applications expand through advanced ink formulations, developing fundamental fluid mechanics frameworks is essential to replace trial-and-error approaches with predictive design methodologies to enable more precise control over and reliability of the printing process.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"7 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145215610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-03DOI: 10.1146/annurev-fluid-112723-051940
Tanguy Le Borgne, Joris Heyman
Porous media flows are generally viewed as inefficient mixers, where solutes may be dispersed yet poorly mixed, making mixing a critical limiting factor for a wide range of processes. The complexity and opacity of porous structures have long made these dynamics difficult to observe. With emerging experimental techniques, concepts and models of mixing in porous media are rapidly evolving. Recent advances link mixing dynamics to fluid deformation arising in flow through porous materials. Unlike diffusion and dispersion, which only dissipate chemical gradients, fluid shear and stretching amplify and sustain them. This review explores the role of fluid deformation in governing mixing, chemical reactions, and biological processes in porous media. We begin by highlighting key experimental observations that have improved our understanding of mixing in these systems. We then examine the fundamental concepts, models, and open questions surrounding fluid deformation and mixing in porous media, emphasizing their dependence on material structure, heterogeneity, dimensionality, and transient flow phenomena, as well as their interaction with chemical and biological processes.
{"title":"Fluid Deformation and Mixing in Porous Media as Drivers for Chemical and Biological Processes","authors":"Tanguy Le Borgne, Joris Heyman","doi":"10.1146/annurev-fluid-112723-051940","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112723-051940","url":null,"abstract":"Porous media flows are generally viewed as inefficient mixers, where solutes may be dispersed yet poorly mixed, making mixing a critical limiting factor for a wide range of processes. The complexity and opacity of porous structures have long made these dynamics difficult to observe. With emerging experimental techniques, concepts and models of mixing in porous media are rapidly evolving. Recent advances link mixing dynamics to fluid deformation arising in flow through porous materials. Unlike diffusion and dispersion, which only dissipate chemical gradients, fluid shear and stretching amplify and sustain them. This review explores the role of fluid deformation in governing mixing, chemical reactions, and biological processes in porous media. We begin by highlighting key experimental observations that have improved our understanding of mixing in these systems. We then examine the fundamental concepts, models, and open questions surrounding fluid deformation and mixing in porous media, emphasizing their dependence on material structure, heterogeneity, dimensionality, and transient flow phenomena, as well as their interaction with chemical and biological processes.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"28 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145215693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-02DOI: 10.1146/annurev-fluid-120423-012604
Michelle H. DiBenedetto
Microplastic pollution is now ubiquitous in marine environments, posing risks to ecosystem and human health. In order to assess and mitigate this threat, we require accurate prediction of microplastic fate and transport in the ocean. While progress has been made studying global-scale transport pathways, our models often fall short at smaller scales; processes such as vertical transport, horizontal dispersion, particle transformation, and boundary fluxes (e.g., at beaches and the air–sea interface) remain poorly understood. The difficulty lies in the physical features of plastic particles: namely, near-neutral buoyancy in seawater, finite size, and irregular shape. These complexities are compounded by the multiscale forcing from waves and turbulence near the ocean surface where microplastics tend to reside. This review synthesizes recent advances in the fluid dynamics of marine plastic transport, emphasizing the role of fluid–particle interactions in ocean flows and highlighting outstanding challenges.
{"title":"The Fluid Mechanics of Ocean Microplastics","authors":"Michelle H. DiBenedetto","doi":"10.1146/annurev-fluid-120423-012604","DOIUrl":"https://doi.org/10.1146/annurev-fluid-120423-012604","url":null,"abstract":"Microplastic pollution is now ubiquitous in marine environments, posing risks to ecosystem and human health. In order to assess and mitigate this threat, we require accurate prediction of microplastic fate and transport in the ocean. While progress has been made studying global-scale transport pathways, our models often fall short at smaller scales; processes such as vertical transport, horizontal dispersion, particle transformation, and boundary fluxes (e.g., at beaches and the air–sea interface) remain poorly understood. The difficulty lies in the physical features of plastic particles: namely, near-neutral buoyancy in seawater, finite size, and irregular shape. These complexities are compounded by the multiscale forcing from waves and turbulence near the ocean surface where microplastics tend to reside. This review synthesizes recent advances in the fluid dynamics of marine plastic transport, emphasizing the role of fluid–particle interactions in ocean flows and highlighting outstanding challenges.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"37 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145209986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-02DOI: 10.1146/annurev-fluid-112723-053838
Michael Le Bars, Daphné Lemasquerier
Geophysical and astrophysical fluid dynamics (GAFD) is an interdisciplinary field. It encompasses a wide range of fluid systems, from planetary atmospheres and the oceans of Earth and icy moons to the interiors of telluric planets, giant planets, and stars. It also spans vast timescales and space scales. Despite this diversity, GAFD is built on common challenges in fundamental fluid mechanics, requiring a multi-approach strategy that integrates theory, simulations, and experiments to explain observations. This review highlights the role of laboratory experiments in GAFD. We first emphasize recent advances in experimental design, methods, and metrology, including large-scale facilities as well as innovative and analog setups. We then focus on two areas where experiments have driven recent breakthroughs: rotating turbulence and flows involving multiphase and phase-change processes. Finally, we discuss emerging challenges and the potential of outreach experiments to stimulate interest in fluid mechanics among students and the public.
{"title":"Laboratory Experiments in Geophysical and Astrophysical Fluid Dynamics","authors":"Michael Le Bars, Daphné Lemasquerier","doi":"10.1146/annurev-fluid-112723-053838","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112723-053838","url":null,"abstract":"Geophysical and astrophysical fluid dynamics (GAFD) is an interdisciplinary field. It encompasses a wide range of fluid systems, from planetary atmospheres and the oceans of Earth and icy moons to the interiors of telluric planets, giant planets, and stars. It also spans vast timescales and space scales. Despite this diversity, GAFD is built on common challenges in fundamental fluid mechanics, requiring a multi-approach strategy that integrates theory, simulations, and experiments to explain observations. This review highlights the role of laboratory experiments in GAFD. We first emphasize recent advances in experimental design, methods, and metrology, including large-scale facilities as well as innovative and analog setups. We then focus on two areas where experiments have driven recent breakthroughs: rotating turbulence and flows involving multiphase and phase-change processes. Finally, we discuss emerging challenges and the potential of outreach experiments to stimulate interest in fluid mechanics among students and the public.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"74 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145209974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-02DOI: 10.1146/annurev-fluid-100224-110920
Manikandan Mathur, Jithendra Raju Nadimpalli, Eric A. D’Asaro
Internal waves, generated by wind and tides, are ubiquitous in the ocean. Their dissipation and the resulting vertical mixing play an important role in setting the ocean circulation, stratification, and energetics. Ocean models usually parameterize many or all of these effects. The current generation of parameterizations often relies on assumptions of uniform or slowly varying stratification profiles. Here, we review the growing theoretical, modeling, and observational evidence that vertical nonuniformity in the stratification profile can significantly modify the assumed wave dynamics. Linear scattering, wave–wave interactions, and solitary-like internal wave generation in idealized nonuniform stratification profiles are discussed. The nonuniform features in oceanic vertical stratification profiles are characterized, followed by a discussion of the validity of the slowly varying stratification assumption for such profiles. A concerted effort is made to synthesize research in both fluid dynamics and oceanography.
{"title":"Internal Waves in a Nonuniformly Stratified Ocean","authors":"Manikandan Mathur, Jithendra Raju Nadimpalli, Eric A. D’Asaro","doi":"10.1146/annurev-fluid-100224-110920","DOIUrl":"https://doi.org/10.1146/annurev-fluid-100224-110920","url":null,"abstract":"Internal waves, generated by wind and tides, are ubiquitous in the ocean. Their dissipation and the resulting vertical mixing play an important role in setting the ocean circulation, stratification, and energetics. Ocean models usually parameterize many or all of these effects. The current generation of parameterizations often relies on assumptions of uniform or slowly varying stratification profiles. Here, we review the growing theoretical, modeling, and observational evidence that vertical nonuniformity in the stratification profile can significantly modify the assumed wave dynamics. Linear scattering, wave–wave interactions, and solitary-like internal wave generation in idealized nonuniform stratification profiles are discussed. The nonuniform features in oceanic vertical stratification profiles are characterized, followed by a discussion of the validity of the slowly varying stratification assumption for such profiles. A concerted effort is made to synthesize research in both fluid dynamics and oceanography.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"121 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145209973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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 : 2025-10-01DOI: 10.1146/annurev-fluid-112823-104356
Michele Guala, Jiarong Hong
The objective of this contribution is to review more than 80 years of experimental measurements of the settling of snow particles and surrogates in natural and laboratory settings and suggest viable directions for future research. Under the broad category of frozen hydrometeors, snow particles are characterized by a variety of shapes and inertial properties that we broadly refer to as snow morphology attributes and depend on the micrometeorology of the air column, including temperature, relative humidity, wind speed, and turbulence. The uncertainty in the prediction of snow settling velocity is partly due to the significant variability in snow crystal shape, density, and drag properties, as well as the modulating effect of ambient turbulence, which has been observed to affect particle orientation and falling style and enhance or reduce the terminal velocity, as compared to quiescent flow conditions. Because of the complexity of finite-size, nonspherical particles’ interaction with turbulent flows at high Reynolds numbers, we stress the need for simultaneous flow and snow morphology measurements in the field and we review past and current experimental techniques and methodologies.
{"title":"Snow Settling in Atmospheric Turbulence","authors":"Michele Guala, Jiarong Hong","doi":"10.1146/annurev-fluid-112823-104356","DOIUrl":"https://doi.org/10.1146/annurev-fluid-112823-104356","url":null,"abstract":"The objective of this contribution is to review more than 80 years of experimental measurements of the settling of snow particles and surrogates in natural and laboratory settings and suggest viable directions for future research. Under the broad category of frozen hydrometeors, snow particles are characterized by a variety of shapes and inertial properties that we broadly refer to as snow morphology attributes and depend on the micrometeorology of the air column, including temperature, relative humidity, wind speed, and turbulence. The uncertainty in the prediction of snow settling velocity is partly due to the significant variability in snow crystal shape, density, and drag properties, as well as the modulating effect of ambient turbulence, which has been observed to affect particle orientation and falling style and enhance or reduce the terminal velocity, as compared to quiescent flow conditions. Because of the complexity of finite-size, nonspherical particles’ interaction with turbulent flows at high Reynolds numbers, we stress the need for simultaneous flow and snow morphology measurements in the field and we review past and current experimental techniques and methodologies.","PeriodicalId":50754,"journal":{"name":"Annual Review of Fluid Mechanics","volume":"114 1","pages":""},"PeriodicalIF":27.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145203430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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：