Re → 0 — creeping flow, inertia absent

• A body with no lift, and a moment anyway — any Reynolds number — viscosity is absent, which is why the drag is zero · sphere-flow
• A drift made of two things that average to zero — steepness ak = 0.05, one fifth of a wavelength deep — second-order Stokes drift · what-a-parcel-remembers
• A drift made of two things that average to zero — steepness ak = 0.05, one fifth of a wavelength deep — second-order Stokes drift · what-a-parcel-remembers
• A drift made of two things that average to zero — steepness ak = 0.05 unless stated, one fifth of a wavelength deep — second-order Stokes drift · what-a-parcel-remembers
• A duct that forgets everything but one number — 2 mm above the wall in water — the kernel is exact, the Stokes layer · how-long-viscosity-remembers
• A force without the flow that makes it — creeping flow, Re → 0 — an unbounded fluid, so the tube wall is outside it · reciprocity · hero
• A force without the flow that makes it — creeping flow, Re → 0 — the average is exact for a quadratic ambient · reciprocity
• A force without the flow that makes it — creeping flow, Re → 0 — the theorem needs linearity and nothing else · reciprocity
• A force without the flow that makes it — creeping flow, Re → 0 — an unbounded fluid at rest at infinity · reciprocity
• A force without the flow that makes it — creeping flow, Re → 0 — an unbounded fluid, so the tube wall is outside it · reciprocity
• A force without the flow that makes it — creeping flow, Re → 0 — the average is exact for a quadratic ambient · reciprocity
• A force without the flow that makes it — creeping flow, Re → 0 — both fields satisfy μ∇²u = ∇p exactly · reciprocity
• A force without the flow that makes it — St = 0.3 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths
• A layer that is an integral of everything upstream — 100 μm particle in air, released at 1 m/s — Stokes drag with a history term · how-long-viscosity-remembers
• A particle is a low-pass filter — Stokes drag · which-memory-a-number-decides
• A particle is a low-pass filter — Stokes drag · which-memory-a-number-decides
• A particle is a low-pass filter — water droplets in air · which-memory-a-number-decides
• A particle is a low-pass filter — Stokes drag · which-memory-a-number-decides
• A particle is a low-pass filter — water droplets in air · which-memory-a-number-decides
• A particle is a low-pass filter — Stokes drag on the droplet — honest below about 30 µm at these speeds · particle-paths
• A swimmer that cannot go backwards — creeping flow, Re → 0 — the expansion is in kb, here 0.2 · moving-surface · hero
• A swimmer that cannot go backwards — creeping flow, Re → 0 — the expansion is in kb, here 0.2 · moving-surface
• A swimmer that cannot go backwards — creeping flow, Re → 0 — a spherical clean interface, no surfactant · moving-surface
• A swimmer that cannot go backwards — creeping flow, Re → 0 — air in water at 20 °C, clean interface assumed · moving-surface
• A swimmer that cannot go backwards — creeping flow, Re → 0 — the expansion is in kb, here 0.05 · moving-surface
• A velocity nobody has — creeping flow — the linear law holds below a pore Reynolds number of about ten · bed-flow · hero
• A velocity nobody has — creeping flow — the linear law holds below a pore Reynolds number of about ten · bed-flow
• A velocity nobody has — creeping flow — Darcy's law is a low-Reynolds statement · bed-flow
• A velocity nobody has — creeping flow — Poiseuille's law inside each tube · bed-flow
• A velocity nobody has — creeping flow — both sides are low-Reynolds results · bed-flow
• A velocity nobody has — creeping flow — Darcy's law is a low-Reynolds statement · bed-flow
• A velocity nobody has — creeping flow — the linear law holds below a pore Reynolds number of about ten · bed-flow
• A velocity nobody has — creeping flow — Poiseuille's law inside each tube · bed-flow
• A velocity nobody has — creeping flow — both sides are low-Reynolds results · bed-flow
• A viscosity made of particles — creeping flow, Re → 0 — rigid neutrally buoyant spheres, no Brownian motion · what-viscosity-is · hero
• A viscosity made of particles — creeping flow, Re → 0 — the ambient has been subtracted, so this is the addition · what-viscosity-is
• A viscosity made of particles — creeping flow, Re → 0 — the theorem needs linearity and nothing else · reciprocity
• A viscosity made of particles — creeping flow, Re → 0 — one rigid sphere in an unbounded straining field · what-viscosity-is
• A viscosity made of particles — creeping flow, Re → 0 — rigid neutrally buoyant spheres, no Brownian motion · what-viscosity-is
• A viscosity made of particles — creeping flow, Re → 0 — one rigid sphere in an unbounded straining field · what-viscosity-is
• A viscosity made of particles — creeping flow, Re → 0 — rigid neutrally buoyant spheres, no Brownian motion · what-viscosity-is
• A viscosity that depends on the question — creeping flow, Re → 0 — rigid neutrally buoyant spheres, no Brownian motion · what-viscosity-is
• A wall that is not quite there — creeping flow — Darcy's law is a low-Reynolds statement · bed-flow
• An oscillation with somewhere to go — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• An oscillation with somewhere to go — deep water, steepness 0.1 — the drift is second order and the field is first · mean-field
• An oscillation with somewhere to go — laminar — the layer is thinner than any turbulence it might sit under · oscillating-wall
• Everything about the start, except one vector — laminar — the layer is thinner than any turbulence it might sit under · oscillating-wall
• How long a fluid takes to forget it was not rotating — water — the exponent is the diffusion equation's, the Stokes layer · how-long-viscosity-remembers
• How small is small enough — a sphere, Re on the diameter; the expansion itself is asymptotic as Re → 0 · creeping-flow · hero
• How small is small enough — a sphere, Re on the diameter; the expansion itself is asymptotic as Re → 0 · creeping-flow
• How small is small enough — Re → 0, rooms from 4 to 1024 radii · creeping-flow
• How small is small enough — Re → 0, rooms from 4 to 1024 radii · creeping-flow
• The cheapest shape the walls allow — creeping flow — inertia is absent, and nothing outside the corner enters the answer · corner-eddy
• The drag that integrates a whole history — 100 μm at 2500 kg/m³ in air — Stokes regime, particle time constant 77 ms · how-long-viscosity-remembers · hero
• The drag that integrates a whole history — 100 μm at 2500 kg/m³ in air — Stokes regime, particle time constant 77 ms · how-long-viscosity-remembers
• The drag that integrates a whole history — 100 μm particle in air, released at 1 m/s — Stokes drag with a history term · how-long-viscosity-remembers
• The drag that integrates a whole history — 100 μm particle in air, released at 1 m/s — Stokes drag with a history term · how-long-viscosity-remembers
• The drag that integrates a whole history — 100 μm particle in air, beyond two particle time constants — Stokes drag with a history term · how-long-viscosity-remembers
• The drag that integrates a whole history — 100 μm particle in air — 1,200 steps over 0.4 s, Stokes drag with a history term · how-long-viscosity-remembers
• The drag that integrates a whole history — 100 μm at 2500 kg/m³ in air, released at 1 m/s · how-long-viscosity-remembers
• The drag that integrates a whole history — air, ν = 1.5e-5 m²/s — a 1 mm sphere, amplitude irrelevant · oscillating-wall
• The drift a closed box will not allow — the same wave in a closed channel · kinematic-exact · hero
• The drift a closed box will not allow — amplitude 0.1, wavenumber 1, depth 5 — a steepness of 0.1 · kinematic-exact
• The drift a closed box will not allow — twenty thousand depth points · kinematic-exact
• The drift a closed box will not allow — the same wave in a closed channel · kinematic-exact
• The drift in a wave that has none — deep water, steepness 0.1 — the drift is second order and the field is first · mean-field
• The drift in a wave that has none — deep water, steepness 0.05 — the drift is second order and the field is first · mean-field
• The drift in a wave that has none — laminar — the layer is thinner than any turbulence it might sit under · oscillating-wall
• The eddies nobody stirs — creeping flow — inertia is absent, and nothing outside the corner enters the answer · corner-eddy · hero
• The eddies nobody stirs — creeping flow — inertia is absent, and nothing outside the corner enters the answer · corner-eddy
• The eddies nobody stirs — creeping flow — the exponent is a property of the geometry alone · corner-eddy
• The eddies nobody stirs — creeping flow — the ratios are geometry and carry no velocity in them · corner-eddy
• The eddies nobody stirs — creeping flow — inertia is absent, and nothing outside the corner enters the answer · corner-eddy
• The eddies nobody stirs — creeping flow — the comparison is of boundary conditions, not of regimes · corner-eddy
• The eddies nobody stirs — creeping flow — inertia is absent, and nothing outside the corner enters the answer · corner-eddy
• The exact theory, drawn by viscosity — gap Reynolds number 4.0e+1, reduced 1.6e+0 · ideal-cylinder · hero
• The exact theory, drawn by viscosity — gap Reynolds number 4.0e+1, reduced 1.6e+0 · ideal-cylinder
• The exact theory, drawn by viscosity — the profile the depth average is an average of · ideal-cylinder
• The flow with no solution — a unit cylinder inside a boundary at R · viscous-limit
• The flow with no solution — R/a from ten to 10¹² · viscous-limit
• The flow with no solution — a unit cylinder inside a boundary at R · viscous-limit
• The flow with no solution — a circular cylinder at low Reynolds number · viscous-limit
• The groups are not the only groups — Reynolds numbers from 0.05 to 10⁴ — holds before any experiment · constraint-and-freedom
• The layer that stops at a depth — f = 1 Hz, ν = 0.000001 m²/s · laminar, no mean flow · oscillating-wall
• The mean is not the flow — deep water, steepness 0.1 — the drift is second order and the field is first · mean-field
• The outlet is the inlet, a while ago — creeping flow — the linear law holds below a pore Reynolds number of about ten · bed-flow
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field · hero
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The pump that is better the more it squeezes — creeping flow: long wavelength, no inertia, a sinusoidal wave on a symmetric two-dimensional channel · velocity-field
• The surface that moves with the flow — creeping flow, Re → 0 — a spherical clean interface, no surfactant · moving-surface · hero
• The surface that moves with the flow — creeping flow, Re → 0 — a clean interface, viscosity ratio 0.5 · moving-surface
• The surface that moves with the flow — creeping flow, Re → 0 — a spherical clean interface, no surfactant · moving-surface
• The surface that moves with the flow — creeping flow, Re → 0 — a clean interface with no surfactant on it · moving-surface
• The surface that moves with the flow — creeping flow, Re → 0 — air in water at 20 °C, clean interface assumed · moving-surface
• The surface that moves with the flow — creeping flow, Re → 0 — a clean interface with no surfactant on it · moving-surface
• The surface that moves with the flow — creeping flow, Re → 0 — rigid neutrally buoyant spheres, no Brownian motion · what-viscosity-is
• The surface that moves with the flow — creeping flow, Re → 0 — a clean interface, viscosity ratio 0.02 · moving-surface
• The theory that solves everything — gap Reynolds number 4.0e+1, reduced 1.6e+0 · ideal-cylinder
• The theory with no memory in it — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• The three that never converge — Reynolds numbers from 0.1 to 10⁻²⁰, creeping flow past a cylinder · regime-exact
• The tracer that is not one — Stokes drag, small particle Reynolds number, no history term — stated, not solved · particle-paths · hero
• The tracer that is not one — Stokes drag, small particle Reynolds number, no history term — stated, not solved · particle-paths
• The tracer that is not one — Stokes drag on the droplet — honest below about 30 µm at these speeds · particle-paths
• The tracer that is not one — Stokes drag, small relaxation time, a steady swirling flow — no history term · particle-paths
• The tracer that is not one — any Reynolds number for the flow; the particle drag is Stokesian by assumption · particle-paths
• The tracer that is not one — St = 1 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths
• The tracer that is not one — any Reynolds number for the flow; Stokes drag on the particle · particle-paths
• The wall that shakes — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall · hero
• The wall that shakes — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• The wall that shakes — f = 100 Hz, ν = 0.000015 m²/s · laminar by construction, no mean flow · oscillating-wall
• The wall that shakes — laminar — the layer is thinner than any turbulence it might sit under · oscillating-wall
• The wall that shakes — f = 1000 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• The wall that shakes — f = 100 Hz · laminar; no mean flow, so nothing here is a boundary layer · oscillating-wall
• The wall that shakes — air, ν = 1.5e-5 m²/s — a 1 mm sphere, amplitude irrelevant · oscillating-wall
• The wall the fluid is listening to — 2 mm above the wall in water — the kernel is exact, the Stokes layer · how-long-viscosity-remembers · hero
• The wall the fluid is listening to — 2 mm above the wall in water — the kernel is exact, the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — 2 mm above the wall in water — the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — 2 mm above the wall in water — the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — water — the exponent is the diffusion equation's, the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — water; the oscillating case at one radian a second — the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — 2 mm above the wall in water unless stated — the Stokes layer · how-long-viscosity-remembers
• The wall the fluid is listening to — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• The wall the fluid is listening to — 100 μm particle in air, beyond two particle time constants — Stokes drag with a history term · how-long-viscosity-remembers
• The world with no inertia — Re → 0, rooms from 4 to 1024 radii · creeping-flow
• The world with no inertia — a sphere, Re on the diameter; the expansion itself is asymptotic as Re → 0 · creeping-flow
• Three dimensions are kinder — any Reynolds number — viscosity is absent, which is why the drag is zero · sphere-flow · hero
• Three dimensions are kinder — any Reynolds number — viscosity is absent, which is why the drag is zero · sphere-flow
• Three dimensions are kinder — any Reynolds number — the argument is topological and carries no velocity · sphere-flow
• Twice as slippery along as across — flat menisci that carry no stress · extra-condition
• Twice as slippery along as across — Stokes flow; velocities in units of shear rate × period · extra-condition
• Twice as slippery along as across — Stokes flow; 240 modes, heights in periods · extra-condition
• Twice as slippery along as across — Stokes flow over flat stripes; any period · extra-condition
• Twice as slippery along as across — Stokes flow — first-order in mode count, extrapolated · extra-condition
• Two rings leapfrog only if they start alike — core 0.06, core volume conserved; coaxial thin-cored filaments, Γ equal, exact mutual field; inviscid · vortex-ring
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — a 1 mm sphere, amplitude irrelevant · oscillating-wall · hero
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — the layer is √(2ν/ω) thick throughout · oscillating-wall
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — a 1 mm sphere, amplitude irrelevant · oscillating-wall
• What a fluid takes out of a swing — f = 100 Hz, ν = 0.000015 m²/s · laminar, no mean flow · oscillating-wall
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — spheres standing in for real shapes · oscillating-wall
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — the layer is √(2ν/ω) thick throughout · oscillating-wall
• What a fluid takes out of a swing — f = 100 Hz, ν = 0.000015 m²/s · laminar by construction, no mean flow · oscillating-wall
• What a fluid takes out of a swing — air, ν = 1.5e-5 m²/s — a 1 mm sphere, amplitude irrelevant · oscillating-wall
• Whether the droplet turns — St = 1 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths · hero
• Whether the droplet turns — St = 1 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths
• Whether the droplet turns — any Reynolds number for the flow; the particle drag is Stokesian by assumption · particle-paths
• Whether the droplet turns — any Reynolds number for the flow; Stokes drag on the particle · particle-paths
• Whether the droplet turns — St = 0.08 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths
• Whether the droplet turns — St = 4 · any Reynolds number for the flow; the particle drag is Stokesian · particle-paths
• Whether the droplet turns — Stokes drag on the droplet — honest below about 30 µm at these speeds · particle-paths
• Whether the droplet turns — Stokes drag, small relaxation time, a steady swirling flow — no history term · particle-paths
• Whether the droplet turns — Re → 0, rooms from 4 to 1024 radii · creeping-flow

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