Article
Engineering, Multidisciplinary
Hadar Ben-Gida, Roi Gurka
Summary: This study investigates whether stationary leading-edge vortices (LEV) can form over nonlinear swept-back high-aspect-ratio (high-AR) wings inspired by the wing shape of the common swift. The results suggest that the common swift can generate stationary LEVs over its swept-back wings, potentially supporting up to 60% of its weight.
BIOINSPIRATION & BIOMIMETICS
(2022)
Article
Multidisciplinary Sciences
Rachel M. Starkweather, Svetlana V. Poroseva, David T. Hanson
Summary: This paper reveals the shape of the leading-edge cross section of a cicada's wing for the first time and analyzes its variability along the wing. It also identifies and quantifies similarities in characteristic dimensions of this shape in the wings of three different cicada species.
SCIENTIFIC REPORTS
(2021)
Article
Mechanics
Kevin J. Wabick, Kyle C. Johnson, Randall L. Berdon, Brian S. Thurow, James H. J. Buchholz
Summary: Plenoptic particle image velocimetry and surface pressure measurements were used to analyze the early development of leading-edge vortices (LEVs) created by a flat-plate wing rolling in a uniform flow. Different conditions were considered, including different advance coefficients and wing radii of gyration. The vorticity sources and sinks were quantified for a control region using a vorticity transport framework, revealing distinct patterns of vortex evolution and vorticity transport mechanisms. Changes in radius of gyration and advance ratio had significant effects on the vortex stability and transport processes.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Engineering, Aerospace
T. Dimopoulos, D. Paliaikos, V. Christou, P. Kaparos-Tsafos, P. Panagiotou
Summary: This study investigates a scaled-down Blended Wing Body (BWB) Unmanned Aerial Vehicle (UAV) model using a combination of experimental and computational methods. Experimental techniques such as surface oil flow visualization and Laser-Doppler Anemometry (LDA) are employed to examine the vortical structures and measure velocity and vorticity profiles. Computational fluid dynamics (CFD) analyses are conducted, comparing the results to the experimental measurements and highlighting important flow characteristics. The findings provide insights into vortical phenomena in and around BWB configurations and offer conclusions on the tradeoffs between accuracy and computational efficiency.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Hamed Khodabakhshian Naeini, Mahdi Nili-Ahmadabadi, Yoon Seong Park, Kyung Chun Kim
Summary: The experimental results demonstrate that the use of nature-inspired needle-shaped vortex generators (VGs) on a double-delta wing significantly improves the flow structure by increasing flow momentum, energizing near-surface flow, creating a more concentrated vortex system, and delaying vortex breakdown.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Computer Science, Interdisciplinary Applications
Kaan Yutuk, Alp Tikenogullari, Ismail H. Tuncer
Summary: This study investigates vortex dominated flows over a close-coupled canard-wing-body configuration at high angles of attack using the open-source flow solver SU2 in a parallel computing environment. Validation studies and comparisons with experimental and numerical studies show that SU2 accurately predicts vortex dynamics, breakdown, induced surface pressure distributions, and aerodynamic loads for canard-wing-body configurations at high angles of attack.
COMPUTERS & FLUIDS
(2021)
Article
Engineering, Aerospace
Sergen Tumse, Ilyas Karasu, Besir Sahin
Summary: The ground effect has a significant impact on the vortical flow characteristics of nonslender delta wings, leading to premature leading-edge vortex breakdown and complex disorganized flow structures.
JOURNAL OF AEROSPACE ENGINEERING
(2022)
Article
Engineering, Aerospace
Yue Wu, Changchuan Xie, Chao Yang
Summary: This paper presents a two-dimensional vortex method with an artificial boundary to address the flow separation problem during high-angle-of-attack flight. The method demonstrates good performance in simulating such flight conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Xuan Bai, Hao Zhan, Baigang Mi
Summary: Based on the bionic design of humpback whale fin, a passive flow control method using wavy leading edge structure was proposed to increase the flapping lift of straight symmetrical flapping wing. CFD numerical simulation was used to compare and analyze the aerodynamic performance and flow field characteristics of straight wing and wavy leading edge flapping wing with different parameters. The simulation results showed that the wavy leading edge structure changed the flow field and increased the lift by reducing the pressure on the upper surface during downward flapping.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Mechanical
Longfei Cong, Bin Teng, Lifen Chen, Wei Bai, Ruijia Jin, Biaosong Chen
Summary: The excellent aerodynamic performance of birds and bats during flying and propulsion has been studied by adopting a low aspect-ratio wing flapping in uniform flow. A bio-inspired flow controlling strategy based on active wing-chord adjustment has been proposed to achieve aerodynamic enhancement. The effects of stretching pattern and aspect ratio on the aerodynamic performance of the wing have been investigated. The results show that in-phase active controlling delays Leading Edge Vortex (LEV) detachment and enhances Trailing Edge Vortex (TEV), while out-phase wing-chord adjustment leads to flow separation and performance deterioration of the wing. The study also reveals that the aerodynamic performance of the flapping wing is susceptible to the stretching phase of wing-chord.
JOURNAL OF FLUIDS AND STRUCTURES
(2023)
Article
Engineering, Multidisciplinary
Tanner Saussaman, Asif Nafi, David Charland, Hadar Ben-Gida, Roi Gurka
Summary: This study investigates the effects of leading-edge serrations on the flow dynamics over an owl wing model. The results show that the serrations modify the boundary layer differently at different angles of attack. At low angles, the serrations enhance turbulence activity, while at 20 degrees angle of attack, they suppress turbulence and reduce aerodynamic noise scattering.
BIOINSPIRATION & BIOMIMETICS
(2023)
Article
Engineering, Marine
Jing Li, Chunbao Liu, Xiaoying Li
Summary: This study quantitatively and qualitatively examines the effects of wavy leading-edge protuberances on a Clark-y three-dimensional hydrofoil. The results demonstrate that protuberances acting as vortex generators significantly enhance the momentum transfer of streamwise vortices and improve the hydrodynamics of the hydrofoil. Understanding the effects of leading-edge protuberances on flow control is essential for new hydrofoils or propeller designs.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Mechanical
Mohammad-Reza Pendar, Jose Carlos Pascoa
Summary: The present study investigates the use of wavy leading-edge (WLE) airfoils in combination with curved multidielectric barrier discharge (DBD) plasma actuators as hybrid passive and active flow control mechanisms. The impact of these mechanisms on the flow field is analyzed, including the frequency and noise signals, acoustic effect, vortical structure, aerodynamic forces, velocity variation, and spanwise flow. Two specific DBD plasma actuators are designed and a large eddy simulation (LES) turbulence model is used. The study also employs continuous wavelet transform (CWT) and fast Fourier transform (FFT) methods to analyze the plasma flow spectral content. The results demonstrate that using DBD plasma actuators with WLE airfoils leads to reduced flow separation, faster turbulent transition, and improved efficiency and noise reduction under low Reynolds number conditions.
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Aerospace
Chengen Yuan, Dongli Ma, Yuhong Jia, Muqing Yang, Liang Zhang
Summary: This paper studies the characteristics of Pitch-Break for Lambda wing and identifies the initial airflow separation position of the outer wing as the main cause for generating nonlinear moment. The airflow separation position is generally affected by leading edge vortex and trailing edge spanwise airflow. Two conclusions are obtained from the analysis of key parameters. To solve the aerodynamic problem of Pitch-Break, the paper proposes the use of an all moving wingtip (AMT) as an auxiliary aileron, which shows minor fluctuations during the Pitch-Break zone compared to conventional aileron. The results demonstrate the engineering feasibility of the all moving wingtip auxiliary aileron and highlight the defect of conventional aileron pitch control at high angles of attack.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Muthukumar Muthuramalingam, Edward Talboys, Hermann Wagner, Christoph Bruecker
Summary: This study presents a novel mechanism for laminar flow control on straight and backward swept wings, inspired by owl feathers. By designing a comb-like device based on owl feather barbs and conducting experiments and numerical studies, the researchers found that this device creates a flow turning effect in the boundary layer to counteract cross-flow, ultimately delaying transition. The observed effect is expected to contribute to a more silent flight in owl flight.
BIOINSPIRATION & BIOMIMETICS
(2021)
Article
Engineering, Mechanical
Huang Chen, Yuanchao Li, David Tan, Joseph Katz
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2017)
Article
Engineering, Mechanical
Huang Chen, Yuanchao Li, Subhra Shankha Koley, Nick Doeller, Joseph Katz
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2017)
Article
Engineering, Mechanical
Yuanchao Li, Huang Chen, Joseph Katz
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2017)
Article
Engineering, Mechanical
Huang Chen, Yuanchao Li, Joseph Katz
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2019)
Article
Engineering, Mechanical
Yuanchao Li, Huang Chen, David Tan, Joseph Katz
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2019)
Article
Engineering, Mechanical
Huang Chen, Nick Doeller, Yuanchao Li, Joseph Katz
JOURNAL OF FLUIDS ENGINEERING-TRANSACTIONS OF THE ASME
(2020)
Article
Engineering, Mechanical
Huang Chen, Yuanchao Li, Subhra Shankha Koley, Joseph Katz
Summary: The study focused on the turbulence characteristics in the tip region of an axial turbomachine, revealing that axial casing grooves lead to a more complex flow structure and significant turbulence anisotropy, with notable variations in the distribution of Reynolds stresses.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Mechanical
Subhra Shankha Koley, Huang Chen, Ayush Saraswat, Joseph Katz
Summary: This experimental study investigates the interactions of axial casing grooves with flow in an axial turbomachine. Different types of grooves have varying effects on machine performance, with U grooves reducing stall flowrate but degrading efficiency, and S grooves improving stall flowrate without efficiency degradation. Stereo-PIV measurements provide insights into the mechanisms involved in these interactions.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2021)
Article
Engineering, Biomedical
Martin L. Tomov, Lilanni Perez, Liqun Ning, Huang Chen, Bowen Jing, Andrew Mingee, Sahar Ibrahim, Andrea S. Theus, Gabriella Kabboul, Katherine Do, Sai Raviteja Bhamidipati, Jordan Fischbach, Kevin McCoy, Byron A. Zambrano, Jianyi Zhang, Reza Avazmohammadi, Athanasios Mantalaris, Brooks D. Lindsey, David Frakes, Lakshmi Prasad Dasi, Vahid Serpooshan, Holly Bauser-Heaton
Summary: This research uses an in vitro model to simulate vascular anastomosis in pulmonary arteries and aid in surgical planning to reduce vascular restenosis. By utilizing bioprinting technology to reconstruct intervascular connections within bifurcated pulmonary arteries, the study found that vascular geometry and flow hemodynamics significantly affect endothelial cell viability, proliferation, alignment, microcapillary formation, and metabolic profiles.
ADVANCED HEALTHCARE MATERIALS
(2021)
Article
Engineering, Mechanical
Subhra Shankha Koley, Ayush Saraswat, Huang Chen, Joseph Katz
Summary: This study investigates the impact of axial casing groove geometry on turbulent kinetic energy and Reynolds stresses near the rotor tip. Different groove shapes are used to decouple the effects of entraining the tip leakage vortex and causing periodic changes to the incidence angle. The results provide valuable insights for turbulence modeling, highlighting the different mechanisms involved and explaining the observed distribution trends.
JOURNAL OF TURBOMACHINERY-TRANSACTIONS OF THE ASME
(2022)
Article
Engineering, Biomedical
Huang Chen, Breandan Yeats, Kevin Swamy, Milad Samaee, Sri Krishna Sivakumar, Fateme Esmailie, Atefeh Razavi, Pradeep Yadav, Vinod H. Thourani, Venkateshwar Polsani, Lakshmi Prasad Dasi
Summary: This method utilizes known device geometry and image registration-based reconstruction method to accurately recover the geometries of stent and leaflet from CT images. It has low geometric error, requires minimal human inputs, and is robust. It enables finite element analysis and reasonable estimation of stress distribution.
ANNALS OF BIOMEDICAL ENGINEERING
(2022)
Article
Engineering, Biomedical
Huang Chen, Lakshmi Prasad Dasi
Summary: The performance of a transcatheter aortic valve (TAV) can be evaluated by analyzing the flow field downstream of the valve using time-resolved 3D particle tracking velocimetry. This experimental study provides a comprehensive 3D measurement of the flow field downstream of an Edwards SAPIEN 3 using the Shake-the-Box algorithm. The results show the importance of considering the flow downstream of the valve to evaluate the risk of leaflet thrombosis.
ANNALS OF BIOMEDICAL ENGINEERING
(2023)
Article
Engineering, Biomedical
Jae Hyun Kim, Vahid Sadri, Huang Chen, Sanchita Bhat, Keshav Kohli, Raj Makkar, Vasilis C. Babaliaros, Rahul P. Sharma, Ajit P. Yoganathan
Summary: The study investigated the influence of patient-specific aortic geometry on the flow dynamics around Transcatheter Aortic Valve (TAV). Through in vitro experiments, it was found that the curvature of the ascending aorta had a positive correlation with the flow circulation and a negative correlation with the particle washout time. This suggests that the distinct vortical flow patterns in the ascending aorta contribute to reducing the risk of flow stagnation and improving washout time.
ANNALS OF BIOMEDICAL ENGINEERING
(2023)
Proceedings Paper
Engineering, Mechanical
Huang Chen, Primoi Dresar, Bryan Lynch, Paarth Sharma, Christopher Williams, Joseph Katz
PROCEEDINGS OF THE ASME/JSME/KSME JOINT FLUIDS ENGINEERING CONFERENCE, 2019, VOL 3B
(2019)
Article
Engineering, Marine
Yuanchao Li, Huang Chen, Joseph Katz
JOURNAL OF SHIP RESEARCH
(2019)