Article
Mechanics
Suresh Behara, Venu Chandra, N. R. Prashanth
Summary: This study numerically investigates the three-dimensional transition in the wake of two tandem co-rotating cylinders. The results show that the rotation of the cylinders and the change of the streamwise gaps both affect the transition modes and the characteristics of the near-wake flow.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Bartosz Protas, Stefan G. Llewellyn Smith, Takashi Sakajo
Summary: In this study, the rotating and translating equilibria of open finite vortex sheets in two-dimensional potential flows were considered, and new results were obtained regarding their stability. The linear instability of these equilibria was shown, with different growth characteristics of unstable perturbations in time. Interestingly, the stability results were obtained entirely through analytical computations, and comparisons were made with existing results for unbounded, periodic, and circular vortex sheets.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Ming Zhao, Qin Zhang
Summary: In this study, the flow past a rotating step cylinder with a diameter ratio of 0.5 and a Reynolds number of 150 was investigated using three-dimensional numerical simulations. The results show that vortex shedding occurs for both cylinders at rotation rates of 0, 0.5, and 1, but is suppressed for the larger cylinder at rotation rates of 2 and 3, and fully suppressed for both cylinders at a rotation rate of 4. The suppression of vortex shedding for the larger cylinder or both cylinders has significant effects on the wake.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
D. I. Pullin, John E. Sader
Summary: The study focuses on the trailing-edge vortex produced by the start-up motion of a two-dimensional flat plate in an inviscid fluid. A vortex-sheet representation and power-law similarity solution are developed, leading to the discovery of three distinct start-up vortex-structure types. The properties of each type are detailed for special cases, with discussion on numerical and analytical solutions. In addition, singular and degenerate vortex behavior is discovered, and the transition between solution types is examined.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Mechanical
Abbishek Gururaj, Mahyar Moaven, Zu Puayen Tan, Brian Thurow, Vrishank Raghav
Summary: Flow evolution over helicopter rotors, wind turbine blades, and insect wings involves unique phenomena in the rotating frame of reference, which cannot be fully characterized by conventional 3D-PIV techniques. A new Rotating Three-Dimensional Velocimetry (R3DV) technique is proposed in this paper to address this gap and has been experimentally demonstrated to be feasible for investigating rotating flows.
EXPERIMENTS IN FLUIDS
(2021)
Article
Mechanics
G. Arranz, O. Flores, M. Garcia-Villalba
Summary: Numerical simulations are used to explore tandem configurations of two self-propelled flexible flappers with finite span. These configurations are characterized by their hydrodynamic performance and topology, with compact and regular configurations observed depending on the vertical offset H and phase shift φ. The upstream flapper's performance is similar to an isolated flapper, while the downstream flapper's performance is significantly affected by the wake of the leader vortex rings.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Paul Billant
Summary: Despite the belief that rotating flows should exhibit two-dimensional dynamics for rapid background rotation according to the Taylor-Proudman theorem, research has shown that two infinitely long counter-rotating vertical vortices are always unstable to three-dimensional perturbations, even with a large rotation rate. The dominant instability involves quasi-antisymmetric displacements of the two vortices, with a growth rate independent of rotation rate under certain conditions. Ultimately, this instability leads to a full three-dimensional breakdown of the vortex pair, indicating that the Taylor-Proudman theorem may only strictly hold in vertically bounded flows. The typical vertical scale in rapidly rotating unbounded flows is shown to scale with the horizontal scale and Rossby number, revealing self-similarity in the Navier-Stokes equations for Ro << 1 and suggesting the validity of reduced equations for any rapidly rotating unbounded flow.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Soumarup Bhattacharyya, Izhar Hussain Khan, Shivam Verma, Sanjay Kumar, Kamal Poddar
Summary: Experimental study on three-dimensional flow past a circular cylinder executing sinusoidal rotary oscillations reveals different wake modes and characteristics influenced by amplitude and forcing frequency, as observed through water tunnel experiments and flow visualization techniques.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Nikolas Olson Aksamit
Summary: We introduce a mapping method that quantifies and visualizes the full geometry of three-dimensional deformation in fluid flows using Cauchy-Green strain tensor eigenvalues. The mapping system visualizes the role of all three eigenvalues in a single plot, providing a comprehensive understanding of the fluid deformation. We also provide methods to visualize the degree of approximation of limiting deformation states and tools to quantify differences between flows based on the compositional geometry of invariant manifolds.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Thermodynamics
Ashish P. Pawar, Sandip Sarkar, Sandip K. Saha
Summary: This paper proposes a numerical model to study the transition to three-dimensionality and the evolution of vortices in the wake of a blunt-headed cylinder considering air as the working fluid in the range of Reynolds number (Re) 130-2000. An experimental setup is developed to validate the numerical model based on heat transfer characteristics. The study categorizes the flow into dynamically steady symmetric flow (50 <= Re <= 200), dynamically steady unsymmetric flow (220 <= Re <= 270), and unsteady flow (Re >= 280) based on the symmetry and time dependence characteristics. The phenomenon of vortex dislocation during the transition to three-dimensionality, characterized by intermittent low frequency pulsations, is investigated. The aerodynamic characteristics are studied by computing force coefficients and Strouhal number (St), while a brief overview of heat transfer characteristics is also provided. Dynamic mode decomposition (DMD) analysis is conducted to quantitatively determine the critical Re at which secondary instability occurs, providing a clear demarcation of the valid Reynolds number regime for the two-dimensional analysis of blunt-headed cylinder.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2023)
Article
Mechanics
A. Chandel, S. P. Das
Summary: Experimental investigations on the wake of a rotating and translating sphere near a plane wall at moderate Reynolds numbers show different vortex shedding behaviors and wake structures under varying conditions, such as transition from hairpin type to shear layer vortex shedding, Kelvin-Helmholtz instability, and breakdown of larger vortical structures into smaller scales due to strong interaction of vortex rings and boundary layer.
Article
Mechanics
Hongyi Jiang
Summary: The study investigates the three-dimensional wake transition for flow past a diamond cylinder at different Reynolds numbers, revealing variations in wake characteristics such as mode swapping between modes A and B, as well as the gradual disorganization of mode B. It is found that there are major differences in wake properties between a diamond and a circular cylinder, with the decomposition of flow properties aiding in the understanding of these differences. The complex interactions between streamwise and spanwise vortices, as well as the wake transition and base-flow transition, are identified as factors that excite mode B and suppress the subharmonic mode.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Yuji Hattori, Makoto Hirota
Summary: The linear stability of the two-dimensional Taylor-Green vortices in rotating stratified fluids is investigated. Five types of instability are observed, and the conditions and growth rates for each instability are obtained. Realizability of an instability is introduced to predict the existence of unstable modes. The presence of stratification and rotation affects the dominant instability and the mode structures.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Thermodynamics
Xu Zhang, Wenwu Zhou, Chuangxin He, Xin Wen, Di Peng, Yingzheng Liu
Summary: This paper comprehensively investigates the flow and mixing behaviors of a sand dune-inspired jet in crossflow (JICF) using particle image velocimetry (PIV) measurements and delayed detached-eddy simulations (DDES). The results show that the sand dune structure has a significant impact on the flow features and vortex structures, and the mixing strength of the sand dune-inspired JICF is relatively weak.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Marine
Jiabin Liu, Anxin Guo, Hui Li
Summary: This study experimentally investigated the three-dimensional features of wind wave surface in a laboratory and obtained the dispersion law of wind waves. The Dynamic Mode Decomposition (DMD) was used to analyze the wave surface structure. The study provides important insights into the characteristics of wind waves.
Article
Engineering, Biomedical
Jinglin Huang, Morteza Gharib
Summary: This study introduces the use of thermal heating to improve drug mixing in the treatment of AMD, with a focus on the importance of heating location and the effectiveness of heating pads in enhancing drug delivery to the macula. The results presented in this study could potentially lead to the development of a more effective strategy for intravitreal injection and improve patient care quality.
ANNALS OF BIOMEDICAL ENGINEERING
(2021)
Article
Mechanics
Cecilia Huertas-Cerdeira, Andres Goza, John E. Sader, Tim Colonius, Morteza Gharib
Summary: The dynamics of a cantilever plate at non-zero angles exhibit four distinct regimes, including small and large amplitude flapping motions, with different physical mechanisms at play. The plate enters the deflected regime at a lower flow speed with increasing angle of attack, causing the flapping motion to disappear for angles greater than approximately 28 degrees. Additionally, plates with reduced aspect ratios lack a clear distinction between flapping regimes at angles above 8 degrees.
JOURNAL OF FLUID MECHANICS
(2021)
Review
Food Science & Technology
Seyed Mohammad Taghi Gharibzahedi, Brennan Smith
Summary: High pressure treatment can significantly improve the functionality and bioactivity of legume proteins, reduce anti-nutritional factors, and allergenicity. HP-assisted enzymatic hydrolysis can also greatly reduce the stability of legume proteins while enhancing the production of bioactive peptides.
TRENDS IN FOOD SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Applied
Farinaz Golbargi, Seyed Mohammad Taghi Gharibzahedi, Alaleh Zoghi, Mehrdad Mohammadi, Reza Hashemifesharaki
Summary: In this study, the effects of water to solids ratio, power, and irradiation time in microwave-assisted extraction of polysaccharides from melon peels were optimized, with the maximum extraction yield achieved under specific conditions. The purified PMP mainly consisted of D-galacturonic acid, arabinose, glucose, and galactose, showing dose-dependent antiradical and antioxidant behavior. Additionally, PMP exhibited increased foam capacity and emulsifying activity at certain concentrations.
CARBOHYDRATE POLYMERS
(2021)
Review
Food Science & Technology
Seyed Mohammad Taghi Gharibzahedi, Brennan Smith
Summary: Encapsulation is a promising process to protect bioactive compounds, with LPs as efficient carriers. LPs can be used to design innovative delivery systems for improving bioaccessibility and survivability of bioactive materials.
COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY
(2021)
Article
Peripheral Vascular Disease
Leroy L. Cooper, Jian Rong, Niema M. Pahlevan, Derek G. Rinderknecht, Emelia J. Benjamin, Naomi M. Hamburg, Ramachandran S. Vasan, Martin G. Larson, Morteza Gharib, Gary F. Mitchell
Summary: Novel intrinsic frequencies may serve as valuable markers of heart failure risk in the community, with higher omega(1) and Delta omega being associated with increased risk of cardiovascular events and heart failure, while lower omega(2) is associated with reduced risk.
Article
Food Science & Technology
Cansu Ekin Gumus, Seyed Mohammad Taghi Gharibzahedi
Summary: Enriched yogurt products containing omega-3 fatty acids can improve health and reduce the risk of infectious diseases, with encapsulation techniques and fortification processes proving effective in enhancing product quality and nutritional value.
TRENDS IN FOOD SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Mechanical
Marcel Veismann, Christopher Dougherty, Jason Rabinovitch, Amelia Quon, Morteza Gharib
Summary: The study conducted extensive flight dynamics testing on the Ingenuity Mars Helicopter system at NASA's Jet Propulsion Laboratory, and discovered the operating characteristics of fans in low-density environments. A full-scale facility with 441 individually controlled fan units was constructed for aerodynamic testing based on these findings, with the conclusion that commercial fans can operate in a low-density environment at higher RPM but with reduced flow rates.
EXPERIMENTS IN FLUIDS
(2021)
Article
Food Science & Technology
Mehrdad Mohammadi, Nasim Khorshidian, Seyed Mohammad Taghi Gharibzahedi
Summary: The addition of B. persicum essential oil has a significant impact on the oxidation rate and overall sensory acceptability of Iranian animal oil (IAO) during storage, leading to an increase in overall sensory acceptability. B. persicum essential oil contains more bioactive compounds and higher levels of total flavonoids, phenolics, carotenoids, and chlorophyll compared to the other two oils.
JOURNAL OF FOOD QUALITY
(2021)
Article
Computer Science, Information Systems
Mohammed Gharib, Fatemeh Afghah, Elizabeth Serena Bentley
Summary: Cooperative ad-hoc UAV networks have become the primary solution for situations where a communication infrastructure is not feasible. This paper proposes a load-balanced optimized predictive and adaptive routing (LB-OPAR), an SDN-based routing solution that significantly improves network performance.
Article
Computer Science, Hardware & Architecture
Mohammed Gharib, MohammadAmin Fazli
Summary: In this paper, an N-anonymity algorithm is proposed to provide effective anonymity service for data owners, while prohibiting the cloud storage provider from knowing which users are storing the same data. Additionally, an ID-based key management algorithm is proposed as the cornerstone of the secure cloud storage system.
JOURNAL OF SUPERCOMPUTING
(2023)
Article
Computer Science, Information Systems
Mohammed Gharib, Ali Owfi, Fatemeh Afghah, Elizabeth Serena Bentley
Summary: In this article, we propose a Blockchain-based solution called BlocKP to increase the resistance of the network against the node capture attack. BlocKP improves the throughput and flow completion time compared to baseline schemes, while also providing up to 60% improvement in the resistance against the node capture attack.
IEEE INTERNET OF THINGS JOURNAL
(2023)
Proceedings Paper
Computer Science, Information Systems
Mohammed Gharib, Shashidhar Nandadapu, Fatemeh Afghah
Summary: UAVs play an essential role in military and civilian applications, requiring a reliable network for communication and data transfer. LTE networks are considered suitable for UAV communication in rural areas, with higher elevation improving signal quality and faster speeds slightly degrading communication performance.
2021 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS WORKSHOPS (ICC WORKSHOPS)
(2021)
Proceedings Paper
Computer Science, Interdisciplinary Applications
Mohammed Algharib, Fatemeh Afghah
Summary: Cooperative ad hoc UAV networks require essential security services, with cryptography playing a key role. However, the absence of infrastructure in these networks makes conventional key management systems infeasible. This paper proposes a key management algorithm inspired by key pre-distribution, utilizing dynamic UAV movement in 3D space to provide key updates and optimize encryption-decryption steps.
2021 IEEE 22ND INTERNATIONAL SYMPOSIUM ON A WORLD OF WIRELESS, MOBILE AND MULTIMEDIA NETWORKS (WOWMOM 2021)
(2021)
Proceedings Paper
Computer Science, Theory & Methods
Mohammed Gharib, Fatemeh Afghah, Elizabeth Serena Bentley
Summary: The paper proposes an optimized predictive and adaptive routing protocol OPAR for cooperative UAV networks, using linear programming to maximize network performance. It effectively addresses the performance degradation issue of traditional routing protocols in the challenging environment of UAV networks.
IEEE CONFERENCE ON COMPUTER COMMUNICATIONS WORKSHOPS (IEEE INFOCOM WKSHPS 2021)
(2021)