Dean Number

Dean number, abbreviated as De, a dimensionless number, used in momentum transfer for the flow in curved pipes and channels.  The equation and calculation is shown below.

 

Dean Number formula
\(\large{ De = \sqrt { \frac {d}{2 \; r}  } \; \frac {\rho \; v \; d}{ \mu }  = \sqrt { \frac  { d }  { 2 \; r }  } \;  Re  }\)
Symbol	English	Metric
\(\large{ De }\) = Dean number	\(\large{dimensionless}\)
\(\large{ \rho }\)  (Greek symbol rho) = density of fluid	\(\large{\frac{lbm}{ft^3}}\)	\(\large{\frac{kg}{m^3}}\)
\(\large{ d }\) = diameter	\(\large{in}\)	\(\large{mm}\)
\(\large{ \mu }\)  (Greek symbol mu) = dynamic viscosity	\(\large{\frac{lbf-sec}{ft^2}}\)	\(\large{ Pa-s }\)
\(\large{ r }\) = radius of curviture of the path of channel	\(\large{in}\)	\(\large{mm}\)
\(\large{ Re }\) = Reynolds number	\(\large{dimensionless}\)
\(\large{ v }\) = axial velocity scale	\(\large{\frac{ft}{sec}}\)	\(\large{\frac{m}{s}}\)

 

Dean number calculator