Related Experiment Video
Updated: Mar 13, 2026
09:17
Experimental Investigation of the Flow Structure over a Delta Wing Via Flow Visualization Methods
Published on: April 23, 2018
11.3K
Ground effect on the aerodynamics of three-dimensional hovering wings
1Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Block EA 07-08, Singapore 117575, Singapore.
Bioinspiration & Biomimetics
|October 26, 2016
Summary
Ground effect significantly influences hovering insect flight dynamics. Three-dimensional wings exhibit force enhancement, reduction, and recovery regimes, with effects less pronounced than 2D wings due to weaker wake capture.
Area of Science:
- Fluid dynamics
- Aerodynamics
- Bio-inspired engineering
Background:
- Understanding ground effect is crucial for analyzing insect flight and designing micro-aerial vehicles.
- Previous studies on two-dimensional (2D) wings identified distinct aerodynamic force regimes based on ground proximity.
Purpose of the Study:
- To investigate the ground effect on a pair of three-dimensional (3D) hovering wings.
- To analyze the influence of hovering kinematics, wing shapes, and Reynolds numbers (Re) on aerodynamic forces.
Main Methods:
- Combined experimental and numerical simulations.
- Investigation of various hovering kinematics, wing shapes, and Reynolds numbers (Re = 100 and 5000).
Main Results:
- Three ground effect regimes (force enhancement, reduction, recovery) were observed for 3D wings, similar to 2D wings but less significant.
- Leading edge vortex (LEV) remains attached on 3D wings irrespective of ground clearance.
- A 'fountain effect' induced by root vortices interacting with the ground may increase insect body lift.
Conclusions:
- Ground effect on 3D wings is less pronounced than on 2D wings due to weaker wake capture.
- Wing planform changes have minor effects on the overall ground effect trend.
- Reynolds number influences force magnitudes and vortex strengths but not the fundamental ground effect regimes.
Related Concept Videos
01:23Lift
630
Lift is a fundamental aerodynamic force that acts perpendicular to the direction of airflow. It plays a central role in achieving and sustaining flight and in stabilizing various vehicles. Lift primarily originates from pressure differences created across surfaces, such as an airfoil. A lower pressure region forms above the wing, while a higher pressure region forms below it, generating an upward force. This differential results from the shape and orientation of the airfoil, enabling the wing...
630
01:24Absolute Motion Analysis- General Plane Motion
657
Visualize a drone, with its propellers spinning rapidly, hovering mid-air. The fascinating movements and operations of this drone can be comprehended by applying the principle of general plane motion.
As the drone's propellers rotate, an upward force is generated that counteracts the force of gravity, enabling the drone to lift off from the ground. This initial movement of the drone is along a straight path, representing a form of translational motion. In this phase, every point on the...
As the drone's propellers rotate, an upward force is generated that counteracts the force of gravity, enabling the drone to lift off from the ground. This initial movement of the drone is along a straight path, representing a form of translational motion. In this phase, every point on the...
657
01:04Hydrostatic Pressure Force on a Plane Surface
2.3K
When a plane surface is submerged in a fluid, hydrostatic forces develop on the surface due to the fluid's pressure. For horizontal surfaces, the pressure exerted by the fluid is uniform because the depth remains constant. The resultant force is determined by the pressure at the given depth multiplied by the area of the surface, and it acts through the centroid of the surface. For vertical surfaces, the pressure varies with depth, increasing as the distance from the fluid's free surface...
2.3K
01:27Gauss's Law: Planar Symmetry
9.9K
A planar symmetry of charge density is obtained when charges are uniformly spread over a large flat surface. In planar symmetry, all points in a plane parallel to the plane of charge are identical with respect to the charges. Suppose the plane of the charge distribution is the xy-plane, and the electric field at a space point P with coordinates (x, y, z) is to be determined. Since the charge density is the same at all (x, y) - coordinates in the z = 0 plane, by symmetry, the electric field at P...
9.9K
01:26General External Flow Characteristics
580
The study of external flow is essential for creating structures and objects that interact efficiently and safely with moving fluids, such as air or water. When a body is immersed in a flowing fluid, it experiences two primary forces: drag, which opposes motion along the flow direction, and lift, which acts perpendicular to the flow. The shape, size, and orientation of the object influence these forces.Streamlined and Blunt Bodies in External FlowObjects in fluid flow are classified as...
580
01:15Determination of Pi Terms
664
The Buckingham Pi theorem is a valuable method in dimensional analysis, reducing complex relationships between variables into dimensionless terms. Relevant variables in analyzing the lift force on an airplane wing include lift force, air density, wing area, aircraft velocity, and air viscosity. Expressing each variable in terms of fundamental dimensions — mass, length, and time — provides a consistent foundation for constructing these dimensionless terms.
The theorem indicates that the...
The theorem indicates that the...
664