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pyroknife
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If we're considering fluid flow over a plate and found that at one location the flow is turbulent. Is it always the case that there is also a transition and laminar region before that turbulent region on the plate?
SteamKing said:That is going to depend on the flow velocity or however you are calculating Reynold's number for the plate.
pyroknife said:Even if the flow velocity is gigantic, wouldn't there always be a laminar region, even if it is infinitesimally small?
Like for example let's say Velocity=speed of light.
Re=velocity*length/(kinematic viscosity)
Depending on what you classify the critical reynold's # as, you can always solve for a critical length (even if it's miniscule) and anything before that critical length is laminar flow.
Thanks.Chestermiller said:If the reynolds number is defined in terms of distance along the plate, then there will always be a critical length at which the transition occurs. You are working in terms of dimensionless parameters, which is a good thing to do. Incidentally, please stay away from velocities approaching the speed of light until you have had some experience with special relativity. Your results will certainly always apply at values of the dimensionless group v/c much less than unity, which includes all the situations you are likely to ever run into in practice.
Laminar flow is a type of fluid flow in which the particles of the fluid move in smooth, parallel layers with little to no mixing between them. It is characterized by low turbulence and is often described as a "streamlined" flow.
Transition flow is an intermediate type of flow that occurs between laminar and turbulent flow. It is characterized by a mix of smooth and chaotic movement of particles, and is often unstable and difficult to predict.
The transition from laminar to turbulent flow is influenced by factors such as the velocity of the fluid, the viscosity of the fluid, and the surface roughness of the boundary through which the fluid is flowing. Other factors such as temperature, pressure, and flow rate can also play a role.
Turbulent flow is a type of fluid flow in which the particles of the fluid move in an irregular, chaotic manner with high levels of mixing. It is characterized by fluctuations in velocity and pressure, and is often associated with high levels of energy dissipation and increased drag on objects in the flow.
The type of flow in a system can be predicted and controlled by using mathematical models and experimental data to analyze the factors that influence flow behavior. By understanding the properties of the fluid and the conditions within the system, we can make adjustments to control the flow and optimize it for a desired outcome.