Related Experiment Video
Updated: Dec 8, 2025
07:17
Measurement of Dynamic Force Acted on Water Strider Leg Jumping Upward by the PVDF Film Sensor
Published on: August 3, 2018
6.3K
Hydrodynamics of a twisting slender swimmer
Gil Iosilevskii1, Alexander Rashkovsky1
1Faculty of Aerospace Engineering, Technion, Haifa 32000, Israel.
Royal Society Open Science
|September 24, 2020
Summary
Sea snakes use unique torsional waves for swimming, generating significant lift with minimal energy cost. This study reveals how these waves enhance hydrodynamic forces for efficient aquatic locomotion.
Area of Science:
- Biomechanics
- Fluid Dynamics
- Zoology
Background:
- Sea snakes exhibit unique anguilliform swimming with leading torsional waves.
- Understanding the hydrodynamic principles behind their propulsion is crucial.
Purpose of the Study:
- To investigate the effect of torsional waves on hydrodynamic forces in anguilliform swimmers.
- To analyze the generation of thrust and lift through wave combinations.
Main Methods:
- Analytical approach using slender body theory.
- Mathematical modeling of hydrodynamic forces and power requirements.
Main Results:
- Torsional waves and angle of attack generate both thrust and lift.
- Combinations of torsional and lateral waves produce lift equal in magnitude to thrust.
- Lift generation increases tail amplitude but has negligible energetic cost.
Conclusions:
- Torsional waves are key to efficient sea snake locomotion.
- The findings offer insights into bio-inspired propulsion systems.
- Sea snake swimming mechanics present a novel model for hydrodynamic force generation.
Related Concept Videos
01:04Hydrostatic Pressure Force on a Curved Surface
2.3K
Hydrostatic pressure on curved surfaces is a fundamental concept in fluid mechanics with broad applications in the civil engineering field. When fluid is in contact with a curved surface, as in a reservoir, dam, or storage tank, it exerts pressure that varies in magnitude and direction along the curved surface. To assess the total hydrostatic force exerted by the fluid on a curved structure, engineers typically isolate the fluid volume adjacent to the surface and analyze the forces acting on...
2.3K
01:11Buoyancy and Stability for Submerged and Floating Bodies
2.4K
In fluid mechanics, buoyancy and stability are key concepts for understanding the behavior of submerged and floating bodies. When a stationary body is fully or partially submerged in a fluid, the fluid exerts a force on the body known as the buoyant force. This force acts vertically upward through a point called the center of buoyancy, which is the center of the displaced fluid volume. According to Archimedes' principle, the magnitude of the buoyant force is equal to the weight of the fluid...
2.4K
01:30Bernoulli's Equation for Flow Along a Streamline
1.3K
Bernoulli's equation relates the energy conservation in a fluid moving along a streamline. The equation applies to incompressible and inviscid fluids under steady flow. For such a flow, Newton's second law is applied to a small fluid element, which experiences forces due to pressure differences, gravity, and velocity variations. The force balance leads to the following form of Bernoulli's equation:
1.3K
01:22Surface Tension of Fluid
992
Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies...
Surface tension varies...
992
01:15Thin-Walled Hollow Shafts
418
In analyzing a thin-walled hollow shaft subjected to torsional loading, a segment with width dx is isolated for examination. Despite its equilibrium state, this segment faces torsional shearing forces at its ends. These forces are quantitatively described by the product of the longitudinal shearing stress on the segment's minor surface and the area of this surface, leading to the concept of shear flow. This shear flow is consistent throughout the structure, indicating a uniform distribution of...
418
01:12Fluid Pressure over Curved Plate of Constant Width
1.8K
When a curved plate of constant width is submerged in a liquid, the pressure acting normal to the plate varies continuously both in magnitude and direction. Calculating the magnitude and location of the resultant force at a point is often challenging for such cases. One of the methods to determine the resultant force and its location involves separately calculating the horizontal and vertical components of the resultant force. This complex calculation can be simplified by representing the...
1.8K