reyn
Dynamic viscosityexact by definition
The reyn is the pound-force second per square inch, exactly 6894.757293168361 Pa·s. It is the viscosity unit of American bearing and lubrication engineering, and the Sommerfeld number as classically written expects it.
Watch out: The reyn is enormous. Real lubricants are in the microreyn range, so a raw reyn figure for an oil is around 10⁻⁶ and almost always written as μreyn instead. An SAE 30 oil runs a few microreyns hot and around ten cold.
| 1 | 6,894.7573 |
Where the unit came from
Named for Osborne Reynolds, who derived the equation of hydrodynamic lubrication in 1886 and gave his name to rather more than one quantity.
One reyn in every dynamic viscosity unit
| 6,894,760,000 | micropascal second (μPa·s) | |
| 68,947,600 | millipoise (mP) | |
| 16,679,000 | pound per foot hour (lb/(ft·h)) | |
| 6,894,760 | millipascal second (mPa·s) | |
| 6,894,760 | centipoise (cP) | |
| 1,000,000 | microreyn (μreyn) | |
| 68,947.6 | poise (P) | |
| 6,894.76 | pascal second (Pa·s) | |
| 4,633.06 | pound per foot second (lb/(ft·s)) | |
| 144 | pound-force second per square foot (lbf·s/ft²) | |
| 6.89476 | kilopascal second (kPa·s) | |
| 1 | reyn (reyn)this unit |
Solvers that use dynamic viscosity