{{short description|British unit of dynamic viscosity}} {{Other uses|Reyn (disambiguation)}}
In fluid dynamics, the '''reyn''' is a British unit of dynamic viscosity, named in honour of Osbourne Reynolds, for whom the Reynolds number is also named.<ref>Juvinal, Robert C. & Marshek, Kurt M.; ''Fundamentals of machine component design''. 2nd ed., 1991, pp. 480, {{ISBN|0-471-62281-8}}</ref>
==Conversions== By definition, :1 reyn = 1 lb<sub>f</sub> s in<sup>−2</sup>. It follows that the relation between the reyn and the poise is approximately :1 reyn = 6.89476 × 10<sup>4</sup> P.
In SI units, viscosity is expressed in newton-seconds per square meter, or equivalently in pascal-seconds. The conversion factor between the two is approximately :1 reyn = 6894.76 Pa s.
==References== <references />
==External links== * [http://www.sizes.com/units/reyn.htm Reyn] History of the unit
Category:Fluid dynamics Category:Units of dynamic viscosity {{Unit-measurement-stub}} {{Fluiddynamics-stub}}