Unfortunately, there are insufficient experimental data reported in the literature to verify or confirm any of these expressions. Thus, for lack of any other information, Eq. (11-49) is recommended, because it is based on the most detailed analysis. This can be extended beyond the Stokes flow region by incorporating Eq. (11-49) into the equivalent Dallavalle equation,

which can be used to solve the ''unknown velocity'' and ''unknown diameter'' problems as previously discussed. However in this case rearrangement of the dimensionless variables CD and NRe BP into an alternative set of dimensionless groups in which the unknown is in only one group is not possible owing to the form of NRe ;BP. Thus the procedure would be to equate Eqs. (11-50) and (11-11) and solve the resulting equation directly by iteration for the unknown V or d (as the case requires).

0 0

Post a comment