Article
Engineering, Marine
Jiadong Wang, Pengfei Liu, Christopher Chin, Guanghua He, Weijie Mo
Summary: The study conducted a three-dimensional computational analysis on the propulsive performance of auto-pitch wing-inground effect oscillating foil propulsors (APWIGs) and found that both aspect ratio and torsional spring stiffness have significant impacts on performance improvement. An optimal aspect ratio and spring stiffness were identified to achieve the highest efficiency for APWIGs. The study also revealed that a moderate aspect ratio and specific spring stiffness could lead to acceptable efficiency losses and improved hydrodynamics for these propulsors.
Article
Engineering, Ocean
Yongcheng Li, Ziying Pan, Nan Zhang
Summary: Transient numerical simulation using the Overlapping grid technique was conducted to investigate the ground wall effect on the propulsive performance of an oscillating wing. The simulation results revealed that the ground wall significantly impacts the fluid dynamics of the oscillating wing, and an increase in Re number facilitates the growth of thrust force and propulsive efficiency.
APPLIED OCEAN RESEARCH
(2021)
Article
Engineering, Marine
Weijie Mo, Guanghua He, Jiadong Wang, Zhigang Zhang, Yun Gao, Wei Zhang, Liang Sun, Hassan Ghassemi
Summary: This study focuses on investigating the wing-in-ground effect on power extraction performance using oscillating hydrofoils. The study found that the increase in positive pressure on the lower surface of the foil is the main reason for the improvement in power extraction efficiency. Through a parametric study, the optimal power extraction region was identified, and it was observed that the optimal region shifts to higher frequencies as the gap decreases. The simulation of a multi-hydrofoil system experiencing the wing-in-ground effect also showed a significant increase in power extraction efficiency for the middle hydrofoil.
Article
Acoustics
Liam Hanson, Hasan Kamliya Jawahar, Sh. S. Vemuri, Mahdi Azarpeyvand
Summary: The aerodynamic and aeroacoustic characteristics of a two-bladed propeller in ground effect were investigated through experiments in an anechoic chamber. The results showed a significant increase in thrust, torque, and power coefficients when the propeller operated in ground effect. A low-fidelity Blade Element Momentum Theory model was used to validate the aerodynamic results. The measurements of near-field and far-field spectra indicated additional tonal peaks and high-frequency broadband humps when the propeller operated in ground effect compared to an isolated configuration. The study has important practical implications for Urban Air Mobility (UAM), particularly in the design of landing pads and propellers for noise mitigation and aerodynamic performance.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Engineering, Aerospace
Jielong Cai, Sidaard Gunasekaran
Summary: The study extends the investigation of the fixed-pitch small-scale propeller in-ground effect to forward flight conditions with different incidence angles. Various experiments and visualization techniques reveal the presence of three distinct performance zones that depend on the advance ratio and ground distance. The occurrence of fountain and ground vortices at specific conditions affects the power and thrust required, with a decrease in ground effect at higher advance ratios. The development of a normalization method allows the collapse of in-ground-effect performance for different heights, advance ratios, and incidence angles in forward flight.
Article
Engineering, Mechanical
Guanghua He, Weijie Mo, Yun Gao, Jiadong Wang, Zhigang Zhang, Hao Yang, Weihao Mao
Summary: The performance of a semi-passive oscillating hydrofoil with pitching and heaving motion is numerically studied. An optimal set of parameters is identified, achieving a maximum efficiency of 39.90%. The study also highlights the significant impact of the wing-in-ground effect on power extraction.
JOURNAL OF FLUIDS AND STRUCTURES
(2022)
Article
Engineering, Aerospace
Yifei Zhang, Haixin Chen, Yufei Zhang
Summary: This study focuses on the aerodynamic performance of wing affected by propeller using actuator disc method and wing optimization. Results indicate that propeller slipstream and slipstream directions have significant impact on the optimization process, and powered-on optimization with slipstream can achieve better drag reduction results.
CHINESE JOURNAL OF AERONAUTICS
(2021)
Article
Thermodynamics
W. Jiang, Z. Y. Mei, F. Wu, A. Han, Y. H. Xie, D. M. Xie
Summary: The study focused on optimizing the performance of a shrouded oscillating-foil turbine, demonstrating an increase in energy extraction efficiency through adjustments to the geometry of the shroud and flow field. Ultimately, it was concluded that using a flat plate as the shroud is more cost-effective and attractive in engineering practices.
Article
Engineering, Marine
Hao Yang, Guanghua He, Weihao Mao, Weijie Mo, Hassan Ghassemi
Summary: This study investigates the influence of blockage effect and ground effect on the energy-extraction performance of oscillating hydrofoils using a two-dimensional numerical model. The results show that the double-wall configuration greatly improves efficiency, and the drag coefficient correction can remedy the influence of ground effect.
Article
Engineering, Marine
D. B. S. Lopes, G. Vaz, J. A. C. Falcao de Campos, A. J. N. A. Sarmento
Summary: This study examines the potential for using an oscillating hydrofoil to extract energy from gravity waves and propel marine vehicles. It presents both a semi-analytical model and numerical simulations to model active oscillating wave thrusters. The semi-analytical model shows good agreement with published data, while the CFD simulations provide a comprehensive understanding of flow dynamics. These results suggest that the semi-analytical model is useful for preliminary design studies, and the CFD model delivers accurate results for complex cases.
Article
Mechanics
Chenguang Lai, Liangkui Tan, Yujie Zhu, Shengji Zhu, Shigeru Obayashi
Summary: This study numerically examines the aeroacoustic characteristics of a multi-directional wing under the wing-in-ground effect. The results show that different intensities of the wing-in-ground effect led to remarkable differences in the characteristic frequency of aerodynamic noise induced by the multi-directional wing.
Article
Engineering, Aerospace
Andre F. P. Ribeiro, Carlos Ferreira, Damiano Casalino
Summary: This study compares a filament-based free wake panel method to experimental and validated numerical data in order to simulate propeller slipstreams and their interaction with aircraft components. The results show that the free wake panel method is able to successfully capture the slipstream deformation and shearing, making it a useful tool for propeller-wing interaction in preliminary aircraft design.
AEROSPACE SCIENCE AND TECHNOLOGY
(2024)
Article
Physics, Fluids & Plasmas
Suyash Verma, Arman Hemmati
Summary: Numerical investigation was conducted on the propulsive performance and vortex synchronization of an oscillating foil in combined heaving and pitching motion at different reduced frequencies, phase offsets, and Reynolds numbers. The transition from drag to thrust dominance was observed at specific phase offsets and reduced frequencies, coinciding with transitions in near-wake modes. Changing phase offsets only affected the spatial configuration of vortex structures, while the number of vortices shed in one oscillation period remained constant. These findings suggest that wake topology transitions are not always reliable for understanding propulsive mechanisms in fish swimming or underwater propulsion systems.
Article
Remote Sensing
Mingzhi Cao, Kun Liu, Chunqiang Wang, Jingbo Wei, Zijie Qin
Summary: Distributed electric propulsion technology has great potential and advantages in the development of drones. This paper verifies the slipstream effect of a single propeller and optimizes the layout to improve the low-speed performance and increase the cruise duration of the UAV.
Article
Engineering, Marine
Mehmet Oguz Tasci, Sergen Tumse, Besir Sahin
Summary: This study qualitatively and quantitatively examined the vortical flow structures over a 70-deg-swept slender delta wing in ground effect. The results showed that the magnitude of leading-edge vortices decreased as the wing moved closer to the ground, while the inboard flow from the side leading-edge towards the central axis of the wing increased. The size of the leading-edge vortex core region also increased when the wing altitude was lowered towards the ground surface. These findings indicate that the wing aerodynamics is positively affected by its proximity to the ground.
Article
Engineering, Industrial
Mashrura Musharraf, Jennifer Smith, Faisal Khan, Brian Veitch
RELIABILITY ENGINEERING & SYSTEM SAFETY
(2020)
Review
Engineering, Marine
P. Kujala, F. Goerlandt, B. Way, D. Smith, M. Yang, F. Khan, B. Veitch
Article
Engineering, Marine
Randy Billard, Jennifer Smith, Brian Veitch
JOURNAL OF NAVIGATION
(2020)
Article
Computer Science, Cybernetics
Rifat Biswas, Brian Veitch, Sarah D. Power
INTERNATIONAL JOURNAL OF HUMAN-COMPUTER INTERACTION
(2020)
Article
Computer Science, Information Systems
Syed Nasir Danial, Jennifer Smith, Faisal Khan, Brian Veitch
HUMAN-CENTRIC COMPUTING AND INFORMATION SCIENCES
(2019)
Article
Engineering, Industrial
V. Salehi, B. Veitch, M. Musharraf
APPLIED ERGONOMICS
(2020)
Article
Engineering, Chemical
V. Salehi, B. Veitch
JOURNAL OF LOSS PREVENTION IN THE PROCESS INDUSTRIES
(2020)
Article
Environmental Sciences
Zaman Sajid, Faisal Khan, Brian Veitch
MARINE POLLUTION BULLETIN
(2020)
Article
Chemistry, Multidisciplinary
Thomas Browne, Rocky Taylor, Brian Veitch, Pentti Kujala, Faisal Khan, Doug Smith
APPLIED SCIENCES-BASEL
(2020)
Article
Environmental Sciences
Faisal Fahd, Brian Veitch, Faisal Khan
MARINE POLLUTION BULLETIN
(2020)
Article
Engineering, Civil
Doug Smith, Brian Veitch, Faisal Khan, Rocky Taylor
ASCE-ASME JOURNAL OF RISK AND UNCERTAINTY IN ENGINEERING SYSTEMS PART A-CIVIL ENGINEERING
(2020)
Article
Engineering, Marine
Yiyi Xu, Jun Zhao, Shuai Sun, Pengfei Liu
Summary: This study examines the effect of vibration and oscillation on the energy generation performance of horizontal axis tidal turbines using an instrumented testing apparatus. The results show that reducing overall oscillation improves the power coefficient and reduces drag. These findings indicate that reducing vibration is effective and necessary for tidal turbine apparatus.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Marine
Arash Honaryar, Mehdi Iranmanesh, Pengfei Liu, Amir Honaryar
Summary: The welding mechanics of large-scale complex-shaped structures is often overlooked or presumed due to its complexity and time consumption. However, this study presents a time-saving global thermo-mechanical model for a curved outside corner joint, which combines shell and solid finite elements to analyze the deformation and residual stress of an aluminum Autonomous Underwater Vehicle. A suitable polynomial mathematical function is used to control the movement of the welding heat source along the joint. The global shell/3D TEP FEM greatly reduces computational time while accurately predicting the temperature, distortion, and residual stress distributions. The study shows a significant difference in longitudinal residual stress between global and local models. The optimal outcomes are utilized in the production of the AUV, resulting in a reduction in residual stress and welding speed.
Article
Energy & Fuels
Gabriela Grasu, Pengfei Liu
Summary: Floating Offshore Wind has the potential to provide an effective solution for the increasing energy demand of coastal communities around the world if the specific risks associated with this novel technology are understood and evaluated.
Article
Transportation
Randy Billard, Mashrura Musharraf, Brian Veitch, Jennifer Smith
WMU JOURNAL OF MARITIME AFFAIRS
(2020)
Article
Engineering, Ocean
Canjun Yang, Dingze Wu, Puzhe Zhou, Shuyang Ma, Rui Zhou, Xin Zhang, Yang Zhang, Qingchao Xia, Zeliang Wu
Summary: The Argo Global Ocean Observing Network is the preeminent ocean observation network worldwide, but its buoys fail to complete long-term observations in designated sea areas due to their lack of lateral movement. To solve this problem, a portable underwater profiler (PUP) that combines buoy and underwater glider functionalities was developed. The PUP is lightweight, allows for rapid deployment, and enables continuous observation.
APPLIED OCEAN RESEARCH
(2024)
Article
Engineering, Ocean
Knut Andreas Kvale, Bernt Leira, Ole Oiseth
Summary: As future floating bridges become longer, the chance of encountering significant inhomogeneous wave conditions increases. This paper presents an approach to model these conditions using generalized harmonic decomposition and applies it to a conceptual floating bridge model in Norway. The paper focuses on frequency-domain simulation and highlights the importance of considering the coherency in swell sea conditions.
APPLIED OCEAN RESEARCH
(2024)