Related Experiment Video
Updated: Jul 3, 2026
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Intermittency and universality in fully developed inviscid and weakly compressible turbulent flows
Roberto Benzi1, Luca Biferale, Robert T Fisher
1Dip Fisica and INFN Università di Tor Vergata Via della Ricerca Scientifica 1, Rome, Italy.
Physical Review Letters
|July 23, 2008
Summary
High-resolution simulations show that slight compressibility in turbulence does not alter velocity field statistics. Density fields exhibit front-like structures without shock formation in these compressible turbulence studies.
Area of Science:
- Fluid Dynamics
- Computational Physics
- Turbulence Research
Background:
- Understanding turbulence is crucial in fluid dynamics.
- Compressible turbulence effects are not fully understood.
- Numerical simulations are key to studying complex turbulent flows.
Purpose of the Study:
- To investigate statistical properties of intermittency in compressible turbulence.
- To analyze velocity, density, and entropy fields.
- To compare findings with incompressible turbulence.
Main Methods:
- High-resolution numerical simulations of homogeneous and isotropic compressible turbulence.
- Analysis of statistical properties, focusing on intermittency.
- Calculation of average 3D Mach number (approximately 0.3).
Main Results:
- The velocity field's inertial range behavior is statistically similar to incompressible turbulence.
- Slight compressibility and different dissipation mechanisms do not significantly alter velocity statistics.
- Evidence of "front-like" structures observed in the density field, without shock generation.
Conclusions:
- Compressibility effects at Mach 0.3 do not significantly impact the statistical properties of the velocity field in the inertial range.
- Density fields in this regime exhibit unique structures distinct from purely incompressible flows.
- Further research is needed to explore shock formation in more compressible regimes.
Related Concept Videos
01:28Irrotational Flow
Irrotational flow is characterized by fluid motion where particles do not rotate around their axes, resulting in zero vorticity. For a flow to be irrotational, the curl of the velocity field must be zero. This imposes specific conditions on velocity gradients. For instance, to maintain zero rotation about the z-axis, the gradient condition:
01:07Laminar and Turbulent Flow
Fluid dynamics is the study of fluids in motion. Velocity vectors are often used to illustrate fluid motion in applications like meteorology. For example, wind—the fluid motion of air in the atmosphere—can be represented by vectors indicating the speed and direction of the wind at any given point on a map. Another method for representing fluid motion is a streamline. A streamline represents the path of a small volume of fluid as it flows. When the flow pattern changes with time, the streamlines...
01:24Turbulent Flow
Turbulent flow is characterized by unpredictable fluctuations in velocity and pressure, which result in a chaotic fluid movement distinct from the orderly patterns of laminar flow. While laminar flow is governed by smooth, parallel layers with minimal mixing, turbulent flow exhibits highly irregular, three-dimensional patterns. This behavior arises due to instabilities in the fluid's velocity profile, and amplifies as the flow velocity increases. Minor disturbances, known as turbulent spots,...
01:22Couette Flow
Couette flow represents the flow of fluid between two parallel plates, with one plate fixed and the other moving with a constant velocity. This configuration allows for a simplified analysis using the Navier-Stokes equations, which govern fluid motion under conditions of viscosity and incompressibility. For Couette flow, the assumptions include a steady, laminar, incompressible flow with a zero-pressure gradient in the flow direction. This flow type is beneficial for understanding shear-driven...
01:24General Characteristics of Pipe Flow II
When fluid enters a pipe, it first passes through the entrance region, where the velocity profile adjusts due to viscous effects. In this region, a boundary layer forms along the pipe walls and grows until it fully occupies the pipe's cross-section. Once the boundary layer merges, the flow becomes fully developed, with a steady velocity profile that remains consistent along the pipe's length.
The distance to reach a fully developed flow is called the entrance length and depends on the flow...
The distance to reach a fully developed flow is called the entrance length and depends on the flow...
01:28Euler's Equations of Motion
In fluid mechanics, shear stresses arise from viscosity, which represents a fluid's internal resistance to deformation. For low-viscosity fluids, like water, these stresses are minimal, simplifying flow analysis by allowing the fluid to be treated as inviscid, or frictionless. In an inviscid fluid, shear stresses are absent, leaving only normal stresses, which act perpendicularly to fluid elements. Notably, pressure — defined as the negative of the normal stress — remains uniform across...