Related Experiment Video
Updated: Jul 31, 2026
09:49
Visualizing Hyporheic Flow Through Bedforms Using Dye Experiments and Simulation
Published on: November 18, 2015
Hydrodynamics of an open vibrated granular system
J J Brey1, M J Ruiz-Montero, F Moreno
1Física Teórica, Universidad de Sevilla, Apartado de Correos 1065, 41080 Sevilla, Spain.
Summary
This study investigates fluidized granular systems using hydrodynamic and molecular dynamics simulations. Findings reveal unique density and temperature profiles, with a minimum temperature at high altitudes explained by boundary layer effects.
Area of Science:
- Physics
- Granular Materials Science
- Fluid Dynamics
Background:
- Fluidized granular systems are complex, exhibiting unique behaviors under gravity.
- Understanding their steady-state properties is crucial for various industrial and scientific applications.
- Previous models often simplified boundary conditions, potentially limiting accuracy.
Purpose of the Study:
- To investigate the steady-state properties of a fluidized granular system under gravity.
- To analyze density and temperature profiles in an open system.
- To explain the observed temperature minimum using hydrodynamic equations.
Main Methods:
- Employed a combination of hydrodynamic description and molecular dynamics simulations.
- Studied an open system to observe realistic boundary effects.
- Computed the energy dissipated through interparticle collisions.
Main Results:
- Observed a density profile with a maximum and a temperature profile with a minimum at high altitudes.
- The temperature was found to increase beyond the minimum at higher elevations.
- Hydrodynamic equations, incorporating a collisionless boundary layer, successfully explained the temperature minimum.
- Simulations showed good agreement with theoretical predictions.
Conclusions:
- The study successfully characterized the steady-state behavior of fluidized granular systems.
- The inclusion of a collisionless boundary layer is essential for accurately modeling temperature profiles.
- The findings provide a more refined understanding of granular flow dynamics and energy dissipation.
More Related Videos
Related Concept Videos
01:14Pressure of Fluids
There are many examples of pressure in fluids in everyday life, such as in relation to blood (high or low blood pressure) and in relation to weather (high- and low-pressure weather systems). A given force can have a significantly different effect, depending on the area over which the force is exerted. For instance, a force applied to an area of 1 mm2 has a pressure that is 100 times greater than the same force applied to an area of 1 cm2. That's why a sharp needle is able to poke through skin...
01:12Fluid Pressure over Curved Plate of Constant Width
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...
01:09Deriving the Speed of Sound in a Liquid
As with waves on a string, the speed of sound or a mechanical wave in a fluid depends on the fluid's elastic modulus and inertia. The two relevant physical quantities are the bulk modulus and the density of the material. Indeed, it turns out that the relationship between speed and the bulk modulus and density in fluids is the same as that between the speed and the Young's modulus and density in solids.
The speed of sound in fluids can be derived by considering a mechanical wave propagating...
The speed of sound in fluids can be derived by considering a mechanical wave propagating...
01:19Viscosity of Fluid
Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.
01:18Newtonian Fluid: Problem Solving
Newtonian fluids exhibit a constant viscosity, meaning their shear stress and shear strain rate are directly proportional. This property ensures a predictable and stable response to applied forces, maintaining a linear relationship between force and flow. Examples include water, air, and light oils, consistently demonstrating this proportional behavior regardless of external conditions.
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
01:11Pressure Variation in a Fluid at Rest
In a fluid at rest, the pressure at any point beneath the fluid surface depends solely on the depth, not on the container's shape or size. This principle, known as hydrostatic pressure, arises because, in stationary fluids, there is no acceleration, meaning the forces within the fluid balance out. Only vertical forces, caused by the weight of the fluid above, contribute to pressure changes with depth.
When measuring pressure at two different levels within the fluid, the difference in pressure...
When measuring pressure at two different levels within the fluid, the difference in pressure...