Flow past a cylinder at Re 40
A real fluid past a circular cylinder. At low Reynolds number the flow closes up behind the body much as the ideal theory says; as it rises the flow separates and a region of reversed flow appears behind, which is where drag comes from.
25 essays call
viscous-cylinder. The drawing above is what it returns with no arguments at all; every
call below passes it something, because a placement that passes nothing draws whichever member
of the family the generator happens to default to rather than the one its essay argues about.
It is also the blast radius. Changing viscous-cylinder changes every figure listed here
at once, and on this site it may change what they assert as well as what they show —
which is what has to be rebuilt and looked at before the change is believed.
Where it is called
What each of these essays asks for instead of the defaults is on the regime index, which reads the parameters back out of the finished figures rather than out of the placements.
- One number decides which physics applies Regimes and numbers
- Streamlines are not the paths particles take Flows and fields
- The theory that solves everything Ideal flow
- Everything happens in a layer you cannot see Viscosity
- Mass has nowhere to go Flows and fields
- The exact theory says nothing has any drag Ideal flow
- The Reynolds number, and the length in it Regimes and numbers
- When the flow lets go Viscosity
- Where Bernoulli's equation applies What is taught wrongly
- The two theories, side by side Viscosity
- The lift curve, and why it is a straight line Circulation and lift
- How thick is thin Viscosity
- Steady does not mean nothing is happening Flows and fields
- What a photograph of a flow shows What is taught wrongly
- Spin is not the same as going round Flows and fields
- The model that cannot be matched Regimes and numbers
- How much uphill a layer can take Viscosity
- The world with no inertia Regimes and numbers
- Circulation is vorticity, added up Flows and fields
- Three numbers left of a fluid Transition and turbulence
- How many things a flow must be told Flows and fields
- The street this site cannot draw Transition and turbulence
- The air a wing does not carry What is taught wrongly
- Turbulent some of the time Transition and turbulence
- A wake that keeps the drag and forgets the body Transition and turbulence