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Tried to comment on question, need 50 rep. (why??) I believe what you are referring to is viscosity in laminar flow. If I recall correctly, non-laminar flow is a precondition for turbulence, but I believe you can have viscosity which is not turbulent. Is this the direction you had in mind? EDIT: Fluid molecules far away from the object will feel ...

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Well, actually you are looking for a one-parameter group of diffeomorphisms (or isometries if referring to the boost vector field). This group is obtained by solving the differential equation $$\frac{dx}{ds}= X(x(s))\tag{1}$$ with a generic initial condition $z$ at $s=0$ in the manifold $M$ (Minkowski spacetime in your example). $X$ is your vector field on ...

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It completely depends on how the maximum flow rates are enforced. For one extreme, I could imagine a sensor that losslessly watches the flow and, if the max flow is exceeded, closes a valve to limit the flow. In that case, there'd be no difference between the two pipes up to the smaller pipe's 10LPM limit, so the flow would be equally split. On the other ...

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With hydrodynamics we normally find that at low shear rates the flow is limited by the viscosity of the liquid while at high shear rates it's limited by inertial forces and the viscosity doesn't matter. This is the case for flow in a pipe. At low flow rates the pressure drop $\Delta P$ is related to the flow rate $Q$ by the Hagen-Poiseuille equation:  ...

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In Newtonian physics, fluids, like anything else, obey conservation of momentum, or $F=ma$. The Bernoulli principle is just a re-statement of conservation of momentum. The only thing that can change a parcel of fluid's speed (i.e. accelerate it) is a force. One kind of force is a pressure gradient. Another kind of force is gravity. If the fluid is ...

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The flow rate is dependent on the pressure, and the pressure is dependent on the height of water above the hole. Over a short enough period of time, the change in water level can be ignored and the flow rate can be considered constant. At an infinitesimally short scale we get the concept of instantaneous flow, which again can be applied over a short time ...

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The hydraulic radius is half of the geometrical radius. This is odd, no? The hydraulic diameter (in general) is defined to be $4A/P$ ($A$ being cross-sectional area; $P$ being the wetted perimeter). The hydraulic radius (mostly in thermoacoustics) is defined to be $A/P$ (check out Swift's book). Subbing in, you get \$\frac{\pi r^2}{2 \pi r} = ...

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as an auto mechanic i have seen what i concluded is a "zone" of zero pressure without cavitation in the engine cooling system of many autos. no sciencey stuff just no good reason for a radiator or heater hose to have a soft spot that is lower in temperature than an inch away on either side of the anomalous. usually on the returnside to the water pump, the ...

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