All Questions
Tagged with terminology fluid-dynamics
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Name of Equation $Q = \Delta P / R$
A very fundamental equation in understanding fluid flow is $Q = \Delta P / R$. When the flow is through a cylindrical pipe of constant radius, $R=8\eta L/\pi r^4$ can be substituted to give Poiseuille'...
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Dust solutions in general relativity
What is the precise definition of a dust solution in general relativity?
If the Einstein tensor of a metric has only the first diagonal term non-zero, it that sufficient for that solution to be called ...
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Can someone explain 'virtual mass' in fluids in simple words (for a dummy/high schooler)?
so I recently came across the term 'virtual mass' and when I looked up more about it, it just gave me some stuff about fluid mechanics that I dont understand properly. My understanding of virtual mass ...
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What does “eddy” mean in turbulence?
a newbie in turbulence study, very confused about the concept of eddy, I feel the word "eddy" having two meanings in fluid-mechanics maybe more and i'm not sure if i understand correctly.
a ...
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Closure conditions in the form of equation of state
While reading the book "Riemann solvers and numerical methods for fluid dynamics" By E. Toro, the very first paragraph is:
"In this chapter, we present the governing equations for the ...
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What are the different conceptualizations/definitions for what a "the state of matter" is?
My understanding:
So, the classic four states of matter are solid, liquid, gaseous and plasma. My understanding is that they differ along the same axis; the cohesion of their constituent parts. This ...
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What is the hydrodynamic limit exactly and why is it called that?
Hydrodynamics is one of those words which are used everywhere in the literature, but I can not seem to find a clear definition! My idea (which could be wrong) is it is a continuum limit of a theory ...
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Why are non-Newtonian fluids called non-Newtonian when they follow Newton’s third law?
To my understanding, Newton’s third law states that for every action there is an equal and opposite reaction. Therefor if I punch the non-Newtonian fluid harder, there will be a harder reaction force ...
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Name of the Rayleigh–Taylor demonstrator toy
There is a common physics "toy" consisting of two liquids sealed into the space between two sheets of plexiglass. When turned upside down, it demonstrates the Rayleigh–Taylor instability.
I ...
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Explanation of some physical terms related to hydodynamic limit to a non-physicist & Integrable system
I'm a mathematician, and I'm reading an article and am struggling with some of the terminology
related to physics.
[...] This equation is formally obtained from the hydrodynamic limit of the
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What is meant by "inertial forces", in contrast to the "resultant force"?
For example, in the Wikipedia page on Reynolds number it is said:
The Reynolds number is the ratio of inertial forces to viscous forces within a fluid..
In explanations of the Reynolds number, it is ...
- 903
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Fokker--Planck equation - naming a vector field
A Fokker Planck equation for the prob. density $\rho$ may be written in the form of a continuity equation
$$\frac{\partial \rho(x,t)}{\partial t} = - \nabla \cdot \left[ g(x,t) \rho(x,t) \right].$$
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How does one draw and notate a pressure gradient vector arrow?
How does one draw and notate a pressure gradient vector arrow?
In the figure below I drew two options that came to mind: Arrow (1) and associated notation Eqn (1), and Arrow (2) and associated ...
- 1,395
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Name for pouring water oscillations?
When you pour a container of water but then it starts to push against itself and then starts pouring in pulses, what is that phenomena called and is there a way to get rid of it?
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Is there a name of the reactionary force to the pressure drag due to flow separation?
To help me clarify my title's question, let me quote the text from Fundamentals of Aerodynamics, 5th Ed., by Anderson:
P872,
“the aerodynamic drag on a vehicle is the sum of drag due to the
...
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