4.7 Article

Ground test and numerical investigation on aerodynamic performance of a quad tilt-rotor aircraft in ground and water effects

相关参考文献

注意:仅列出部分参考文献,下载原文获取全部文献信息。
Article Engineering, Aerospace

Numerical investigation on unsteady characteristics of ducted fans in ground effect

Yiwei Luo et al.

Summary: Ducted fans are widely used in UAV applications due to their high efficiency, low noise, and high safety. This study evaluates the influence of ground on the aerodynamic performance of ducted fans using sliding mesh technology and the Unsteady Reynolds Averaged Navier-Stokes method. The results show that the ground effect leads to a decrease in duct thrust, an increase in rotor thrust, and a decrease in total thrust. Small-scale stall cells with circumferential movements are observed in ground effect, which cause thrust fluctuations.

CHINESE JOURNAL OF AERONAUTICS (2023)

Article Engineering, Marine

Design and implementation of a gliding cross-domain vehicle

Yucheng Zou et al.

Summary: This paper analyzes the cross-domain process and proposes a novel CDV with two sets of hydrofoils and foldable airfoils to improve hydrodynamic and aerodynamic performance. The functions and mechanisms of the feature structures are investigated through theoretical modeling and numerical simulations. The hydrofoils enable rapid gliding and takeoff, as well as reducing impact during surface landing, while the foldable tandem airfoils contribute to flight stability and efficiency. A prototype with a control system is fabricated and experimented, confirming the feasibility and reliability of the design. The cross-domain method and structural design proposed in this paper provide valuable guidance for future development of novel CDVs.

OCEAN ENGINEERING (2023)

Article Engineering, Aerospace

Distinct Wing-in-Ground Effect of Airfoil in Proximity to Water Waves

Haolin Zhi et al.

Summary: The present study investigates the aerodynamic characteristics of a flying airfoil near water waves. Results suggest that for large ground clearance, the aerodynamic forces and flow structures are dominated by the passage shape between the airfoil and the water wave, which can be substituted by rigid wavy ground. However, for small ground clearance, the airfoil-induced airflow creates strong shear force on the wave, leading to water spray and distinct aerodynamic behavior.

AIAA JOURNAL (2022)

Review Engineering, Marine

Review of hybrid aerial underwater vehicle: Cross-domain mobility and transitions control

Zheng Zeng et al.

Summary: This paper provides a detailed literature review of hybrid aerial vehicles (HAUV) and their cross-domain mobility. It discusses the importance of the control system in ensuring smooth air-water transitions for HAUV and reviews recent developments in this area. The paper also highlights the challenges that need to be addressed in developing HAUV with persistent autonomy.

OCEAN ENGINEERING (2022)

Article Engineering, Aerospace

Numerical simulation of the quadcopter flow field in the vertical descent state

Junjie Wang et al.

Summary: This study investigates the flow fields of a quadcopter and a single rotor in vertical descending through CFD simulation and analyzes the variation laws of lift and power. The results show that the quadcopter and the single rotor enter the vortex ring state (VRS) similar to helicopters, but with differences in terms of descent speed, lift loss, and lift variation. It is recommended to limit the maximum speed of the quadcopter during vertical descending for flight safety.

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING (2022)

Article Engineering, Aerospace

Effect of Partial Ground and Partial Ceiling on Propeller Performance

Jielong Cai et al.

Summary: The experimental study examined the effects of finite extent flat obstacles behind and ahead of a propeller in hover. The results showed that the ground effect on thrust and power is significant for obstacles of the same diameter as the propeller, while it can be neglected for obstacles smaller than half of the propeller diameter. The thrust and power effects of circular and annular plates were found to be superimposable.

JOURNAL OF AIRCRAFT (2022)

Article Engineering, Marine

Vortical flow characteristics of a slender delta wing in ground effect

Mehmet Oguz Tasci et al.

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.

OCEAN ENGINEERING (2022)

Article Engineering, Aerospace

Aerodynamic Interactions of Counter-Rotating Coaxial Rotors Hovering in Ground Effect

Lokesh Silwal et al.

Summary: This study on a counter-rotating coaxial rotor system found that performance increased monotonically with decreasing rotor height during in-ground effect hovering conditions, but individual rotor performance showed nonmonotonic behavior with varying rotor height.

JOURNAL OF AIRCRAFT (2022)

Article Engineering, Aerospace

Experimental and computational investigation on comparison of micro-scale open rotor and shrouded rotor hovering in ground effect

Han Han et al.

Summary: This study compares the aerodynamic performance and flowfield characteristics of OR and SR hovering in-ground effect through experimental measurements and CFD simulations. The results show that in ground effect flight, SR is more sensitive and provides more thrust than OR. Additionally, it is found that as ground distance decreases, back pressure increases more noticeably for SR, leading to a decrease in shroud thrust due to tip leakage flow and flow separation.

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART G-JOURNAL OF AEROSPACE ENGINEERING (2021)

Article Robotics

Quadrotor Drone Hovering in Ground Effect

Yasutada Tanabe et al.

Summary: The study simulated a variable-pitch-controlled quadrotor drone in the ground effect using a high-fidelity CFD solver and found that the power required for the quadrotors generating the same thrust decreases as the rotor height approaches the ground, increases briefly when the rotor height is close to the rotor radius, and then abruptly decreases again as the rotors further approach the ground. The outwash from the quadrotors varies depending on the relative direction to the quadrotor layout, with stronger outwash from the rotor gaps extending to a higher altitude compared to a single rotor configuration.

JOURNAL OF ROBOTICS AND MECHATRONICS (2021)

Article Engineering, Aerospace

Quasi-Steady In-Ground-Effect Model for Single and Multirotor Aerial Vehicles

Xiang He et al.

AIAA JOURNAL (2020)

Article Engineering, Aerospace

Numerical-experimental correlation of hovering rotor aerodynamics in ground effect

Claudio Pasquali et al.

AEROSPACE SCIENCE AND TECHNOLOGY (2020)

Article Engineering, Aerospace

Numerical investigation of the porpoising motion of a seaplane planing on water with high speeds

Xupeng Duan et al.

AEROSPACE SCIENCE AND TECHNOLOGY (2019)

Article Engineering, Aerospace

Vortex Approach for Downwash and Outwash of Tandem Rotors in Ground Effect

Jian Feng Tan et al.

JOURNAL OF AIRCRAFT (2018)

Article Engineering, Aerospace

Numerical Simulations and Measurements of the Helicopter Wake in Ground Effect

Masahiko Sugiura et al.

JOURNAL OF AIRCRAFT (2017)

Article Engineering, Biomedical

Dynamic model and ADRC of a novel water-air unmanned vehicle for water entry with in-ground effect

Duo Qi et al.

JOURNAL OF VIBROENGINEERING (2016)

Article Engineering, Aerospace

Numerical Study of Aerodynamics of a Wing-in-Ground-Effect Craft

Qiulin Qu et al.

JOURNAL OF AIRCRAFT (2014)

Article Engineering, Aerospace

Detailed Computational Investigation of a Hovering Microscale Rotor in Ground Effect

Vinod K. Lakshminarayan et al.

AIAA JOURNAL (2013)

Article Engineering, Multidisciplinary

Lifting line theory for wing-in-ground effect in proximity to a free surface

Z. Zong et al.

JOURNAL OF ENGINEERING MATHEMATICS (2012)

Article Mechanics

A subsonic lifting surface theory for wing-in-ground effect

H. Liang et al.

ACTA MECHANICA (2011)

Article Computer Science, Interdisciplinary Applications

Sliding, mesh algorithm for CFD analysis of helicopter rotor-fuselage aerodynamics

R. Steijl et al.

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS (2008)