A stereo PIV system for measuring the velocity vector in complex gas flows

Stepanov, E. Yu.; Maslov, V. P.; Zakharov, D. L.

doi:10.1007/s11018-009-9318-z

Cited by 31 publications

(4 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Non-contact optical methods are of special note here. These include particle image velocimetry (PIV) [5,6], particle tracking velocimetry (PTV) [7,8], stereo particle image Velocimetry (Stereo PIV) [9,10], interferometric particle imaging (IPI) [11,12] and shadow photography (SP) [13,14]. A major objective of analyzing the gas-vapor-droplet flows [15][16][17][18] is to monitor the component composition, as well as the concentration of droplets, particles, bubbles, vapors, and other components and elements under different heat exchange conditions.…”

Section: Introductionmentioning

confidence: 99%

Interaction of Liquid Droplets in Gas and Vapor Flows

et al. 2019

View full text Add to dashboard Cite

We investigated the conditions, characteristics, and outcomes of liquid droplet interaction in the gas medium using video frame processing. The frequency of different droplet collision outcomes and their characteristics were determined. Four interaction regimes were identified: bounce, separation, coalescence, and disruption. Collision regime maps were drawn up using the Weber, Reynolds, Ohnesorge, Laplace, and capillary numbers, as well as dimensionless linear and angular parameters of interaction. Significant differences were established between interaction maps under ideal conditions (two droplets colliding without a possible impact of the neighboring ones) and collision of droplets as aerosol elements. It was shown that the Weber number could not be the only criterion for changing the collision mode, and sizes and concentration of droplets in aerosols influence collision modes. It was established that collisions of droplets in a gaseous medium could lead to an increase in the liquid surface area by 1.5–5 times. Such a large-scale change in the surface area of the liquid significantly intensifies heat transfer and phase transformations in energy systems.

show abstract

Section: Introductionmentioning

confidence: 99%

Interaction of Liquid Droplets in Gas and Vapor Flows

et al. 2019

View full text Add to dashboard Cite

show abstract

“…However, the dynamic change of flow field and detailed wing folding/deforming of flying creatures are not easy to be recorded due to the limitations of the current experimental observation equipment. Therefore, as shown in figure 23(E), an enhanced experimental testing platform with a stereoscopic PIV system [173] and motion recording system should be established. This platform can precisely capture the kinematic and aerodynamic parameters of the FDWs to reveal the maneuver techniques and wing control mechanisms of flying animals.…”

Section: Experimental Observation and Data Collection Methodsmentioning

confidence: 99%

Bio-inspired flapping wing robots with foldable or deformable wings: a review

Zhang¹,

Zhao

2022

Bioinspir. Biomim.

View full text Add to dashboard Cite

Traditional flapping-wing robots (FWRs) obtain lift and thrust by relying on the passive deformation of their wings which cannot actively fold or deform. In contrast, flying creatures such as birds, bats, and insects can maneuver agilely through active folding or deforming their wings. Researchers have developed many bio-inspired foldable or deformable wings (FDWs) imitating the wings of flying creatures. The foldable wings refer to the wings like the creatures’ wings that can fold in an orderly manner close to their bodies. Such wings have scattered feathers or distinct creases that can be stacked and folded to reduce the body envelope, which in nature is beneficial for these animals to prevent wing damage and ensure agility in crossing bushes. The deformable wings refer to the active deformation of the wings using active driving mechanisms and the passive deformation under the aerodynamic force, which functionally imitates the excellent hydrodynamic performance of the deformable body and wings of the creatures. However, the shape and external profile changes of deformable wings tend to be much smaller than that of folding wings. FDWs enable the FWRs to improve flight degree of flexibility, maneuverability, and efficiency and reduce flight energy consumption. However, FDWs still need to be studied, and a comprehensive review of the state-of-the-art progress of FDWs in FWR design is lacking. This paper analyzes the wing folding and deformation mechanisms of the creatures and reviews the latest progress of FWRs with FDWs. Furthermore, we summarize the current limitations and propose future directions in FDW design, which could help researchers to develop better FWRs for safe maneuvering in obstacle-dense environments.

show abstract

“…In some other cases, one is interested in the internal dynamics of the droplet and especially in the movement of the possible particulate components. For such purpose, particle tracking-based approaches, that is, particle image velocimetry, , can be used but are limited to situations where the colloidal droplet is dilute (transparent) and the suspended particles are sufficiently large. Some implementations have been improved to construct, for instance, both the particles’ velocity and concentration fields, by using particles of different sizes that can fluoresce in different channels. , The tracking resolution can be further enhanced using variants of dark field microscopy .…”

Section: Introductionmentioning

confidence: 99%

Continuous Optical Measurement of Internal Dynamics in Drying Colloidal Droplets

Guzmán-Sepúlveda

Dogariu

2021

J. Phys. Chem. B

View full text Add to dashboard Cite

Accessing the colloidal dynamics non-invasively and continuously during the phase transition of a colloidal system is challenging but critical. Here, we demonstrate the use of spatiotemporal coherence-gated light scattering for studying the internal dynamics of drying colloidal droplets. The continuously acquired signal originates from a picoliter-sized volume located at the droplet−substrate interface. The measurement is non-contact, non-invasive, and label free and permits real-time observations of both optical and mechanical changes in the measurement volume. Additionally, some macroscopic descriptors of the drying process can be constructed from the microscopic measurement, providing ample information of the process. Implemented with an endoscopic-like probe, this system can be easily incorporated into the existing drop profiling instruments, which is potential for the full characterization of dynamic colloidal droplets.

show abstract

A stereo PIV system for measuring the velocity vector in complex gas flows

Cited by 31 publications

References 1 publication

Interaction of Liquid Droplets in Gas and Vapor Flows

Interaction of Liquid Droplets in Gas and Vapor Flows

Bio-inspired flapping wing robots with foldable or deformable wings: a review

Continuous Optical Measurement of Internal Dynamics in Drying Colloidal Droplets

Contact Info

Product

Resources

About