Peclet Number

Péclet number, abbreviated as Pe, a dimensionless number, defined as a ratio of heat transport by convection to heat transport by conduction.

 

Peclet Number fromula

\(\large{ Pe =  \frac { v \; \rho \; C  \; l_c }{ k }      }\)

Where:

Units	English	Metric
\(\large{ Pe  }\) = Peclet number	\(\large{dimensionless}\)
\(\large{ l_c }\) = characteristic length	\(\large{ft}\)	\(\large{m}\)
\(\large{ \rho  }\)  (Greek symbol rho) = density	\(\large{\frac{lbm}{ft^3}}\)	\(\large{\frac{kg}{m^3}}\)
\(\large{ Q_{cond}  }\) = heat transfer by conduction	\(\large{\frac{Btu}{hr}}\)	\(\large{W}\)
\(\large{ Q_{conv}  }\) = heat transfer by convection	\(\large{\frac{Btu}{hr}}\)	\(\large{W}\)
\(\large{ C }\) = heat capacity	\(\large{\frac{Btu}{F}}\)	\(\large{\frac{kJ}{K}}\)
\(\large{ k }\) = thermal conductivity	\(\large{\frac{Btu-ft}{hr-ft^2-F}}\)	\(\large{\frac{W}{m-K}}\)
\(\large{ v  }\) = velocity	\(\large{\frac{ft}{sec}}\)	\(\large{\frac{m}{s}}\)

Solve For:

\(\large{ l_c =  \frac { Pe \; k }{ v \; \rho \; C }   }\)
\(\large{ \rho =  \frac { Pe \; k }{ v \; C \; l_c }   }\)
\(\large{ C =  \frac { Pe \; k }{ v \; \rho \; l_c }   }\)
\(\large{ k =  \frac { v \; \rho \; C \; l_c  }{ Pe }   }\)
\(\large{ v =  \frac { Pe \; k }{ \rho \; C \; l_c }   }\)