Temperature Dependence
Water (H₂O)
Dynamic Viscosity (μ)
Absolute viscosity representing water's internal resistance to flow. Decreases significantly with temperature. Critical for pump sizing, pipe flow calculations, and Reynolds number.
Primary Unit
Pa · s (Pascal-seconds)
Alt Unit
mPa · s (millipascal-seconds)
Temperature-Dependent Viscosity
1 atm Pressure| Temp ( °C) | Viscosity (Pa · s (Pascal-seconds)) | Viscosity (mPa · s (millipascal-seconds)) | Notes |
|---|---|---|---|
| 0 | 0.001792 | 1.792 | Freezing point |
| 10 | 0.001307 | 1.307 | |
| 20 | 0.001002 | 1.002 | Standard reference (20 °C) |
| 25 | 0.000890 | 0.890 | Room temperature |
| 30 | 0.000798 | 0.798 | |
| 40 | 0.000653 | 0.653 | |
| 50 | 0.000547 | 0.547 | |
| 60 | 0.000467 | 0.467 | |
| 80 | 0.000355 | 0.355 | |
| 100 | 0.000282 | 0.282 | Boiling point (1 atm) |
Related Equations
Reynolds Number
Re = ρvL / μ = vL / ν
Kinematic Relation
ν = μ / ρ
Temperature Dependence
Water (H₂O)
Kinematic Viscosity (ν)
Ratio of dynamic viscosity to density (ν = μ/ρ). Used in fluid flow analysis, especially for Reynolds number and hydraulic calculations. Units in Stokes or centiStokes.
Primary Unit
m2/s
Alt Unit
cSt (centiStokes)
Temperature-Dependent Viscosity
1 atm Pressure| Temp ( °C) | Viscosity (m2/s) | Viscosity (cSt (centiStokes)) | Notes |
|---|---|---|---|
| 0 | 0.000001787 | 1.787 | Freezing point |
| 10 | 0.000001307 | 1.307 | |
| 20 | 0.000001004 | 1.004 | Standard reference (20 °C) |
| 25 | 0.000000893 | 0.893 | Room temperature |
| 30 | 0.000000801 | 0.801 | |
| 40 | 0.000000658 | 0.658 | |
| 50 | 0.000000553 | 0.553 | |
| 60 | 0.000000474 | 0.474 | |
| 80 | 0.000000364 | 0.364 | |
| 100 | 0.000000294 | 0.294 | Boiling point (1 atm) |
Related Equations
Reynolds Number
Re = ρvL / μ = vL / ν
Kinematic Relation
ν = μ / ρ
Temperature Dependence
Air (Dry)
Dynamic Viscosity (μ)
Absolute viscosity of dry air at atmospheric pressure. Unlike liquids, gas viscosity increases with temperature due to increased molecular momentum transfer.
Primary Unit
Pa · s (Pascal-seconds)
Alt Unit
μPa · s (micropascal-seconds)
Temperature-Dependent Viscosity
1 atm Pressure| Temp ( °C) | Viscosity (Pa · s (Pascal-seconds)) | Viscosity (μPa · s (micropascal-seconds)) | Notes |
|---|---|---|---|
| -20 | 0.0000163 | 16.3 | Cold conditions |
| 0 | 0.0000172 | 17.2 | Freezing point of water |
| 20 | 0.0000182 | 18.2 | Standard reference (20 °C) |
| 25 | 0.0000185 | 18.5 | Room temperature |
| 40 | 0.0000191 | 19.1 | |
| 60 | 0.0000200 | 20.0 | |
| 80 | 0.0000209 | 20.9 | |
| 100 | 0.0000218 | 21.8 | |
| 200 | 0.0000257 | 25.7 | High temperature |
| 400 | 0.0000326 | 32.6 | Very high temperature |
Related Equations
Reynolds Number
Re = ρvL / μ = vL / ν
Kinematic Relation
ν = μ / ρ
Temperature Dependence
Air (Dry)
Kinematic Viscosity (ν)
Kinematic viscosity of air, accounting for density changes with temperature. Essential for aerodynamics, HVAC duct design, and boundary layer calculations.
Primary Unit
m2/s
Alt Unit
cSt (centiStokes)
Temperature-Dependent Viscosity
1 atm Pressure| Temp ( °C) | Viscosity (m2/s) | Viscosity (cSt (centiStokes)) | Notes |
|---|---|---|---|
| -20 | 0.0000116 | 11.6 | Cold conditions |
| 0 | 0.0000133 | 13.3 | Freezing point of water |
| 20 | 0.0000151 | 15.1 | Standard reference (20 °C) |
| 25 | 0.0000156 | 15.6 | Room temperature |
| 40 | 0.0000170 | 17.0 | |
| 60 | 0.0000189 | 18.9 | |
| 80 | 0.0000209 | 20.9 | |
| 100 | 0.0000231 | 23.1 | |
| 200 | 0.0000346 | 34.6 | High temperature |
| 400 | 0.0000623 | 62.3 | Very high temperature |
Related Equations
Reynolds Number
Re = ρvL / μ = vL / ν
Kinematic Relation
ν = μ / ρ