Related Experiment Video
Updated: Jun 9, 2025
10:03
Uncoupling Coriolis Force and Rotating Buoyancy Effects on Full-Field Heat Transfer Properties of a Rotating Channel
Published on: October 5, 2018
8.2K
Canard explosions in turbulent thermo-fluid systems
Ramesh S Bhavi1,2, Sivakumar Sudarsanan1,2, Manikandan Raghunathan1,2
1Department of Aerospace Engineering, Indian Institute of Technology Madras, Chennai, Tamil Nadu 600036, India.
Chaos (Woodbury, N.Y.)
|October 21, 2024
Summary
Researchers discovered a novel "canard explosion" in turbulent reactive flows, showing a continuous transition with bursting oscillations. This phenomenon differs from abrupt jumps, offering new insights into thermo-fluid system dynamics.
Area of Science:
- Fluid Dynamics
- Thermodynamics
- Nonlinear Dynamics
Background:
- Thermo-fluid systems can exhibit catastrophic transitions to high-amplitude oscillations.
- Conventional transitions are abrupt jumps in fluctuation amplitude.
- Turbulent reactive flows present complex dynamic behaviors.
Purpose of the Study:
- To experimentally discover and characterize a novel transition mechanism in turbulent reactive flow systems.
- To investigate the phenomenon of canard explosion and its associated dynamics.
- To develop a phenomenological model explaining the observed canard explosion.
Main Methods:
- Experimental investigation of a turbulent reactive flow system.
- Analysis of fluctuation amplitudes and temperature variations.
- Development and application of a phenomenological model for thermoacoustic systems.
Main Results:
- Observed a continuous bifurcation, termed canard explosion, with a rapid amplitude rise.
- Identified a bursting state with high-amplitude oscillations interspersed with low-amplitude ones.
- Correlated slower time-scale temperature fluctuations with the burst amplitude envelope.
Conclusions:
- The canard explosion represents a unique transition pathway in turbulent reactive flows.
- The bursting behavior is distinct from conventional intermittency and exhibits larger amplitude bursts.
- A phenomenological model explains the canard explosion via slow-fast dynamics at the bifurcation regime.
Related Concept Videos
01:07Laminar and Turbulent Flow
8.4K
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...
8.4K
01:24Turbulent Flow
146
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...
146
01:16Energy Conservation and Bernoulli's Equation
8.6K
Applying the conservation of energy principle or the work-energy theorem to an incompressible, inviscid fluid in laminar, steady, irrotational flow leads to Bernoulli's equation. It states that the sum of the fluid pressure, potential, and kinetic energy per unit volume is constant along a streamline.
All the terms in the equation have the dimension of energy per unit volume. The kinetic energy per unit volume is called the kinetic energy density, and the potential energy per unit volume is...
All the terms in the equation have the dimension of energy per unit volume. The kinetic energy per unit volume is called the kinetic energy density, and the potential energy per unit volume is...
8.6K
01:22Couette Flow
214
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...
214
01:18Newtonian Fluid: Problem Solving
199
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...
199
01:10Poiseuille's Law and Reynolds Number
6.4K
Any fluid in a horizontal tube can flow due to pressure differences—fluid flows from high to low pressure. The flow rate (Q) is the ratio of pressure difference and resistance through a horizontal tube. The greater the pressure difference, the higher the flow rate. The flow resistance is expressed as:
6.4K