CVEN 3313 Chapter Notes - Chapter 7: Stokes Flow, Weber Number, Strouhal Number
Document Summary
Section 7. 04 some additional comments about dimensional analysis. Selection of variables it the most difficult step in applying dimensional analysis as said in the previous section. Typically, in fluid mechanics, the required number of reference dimensions is three, but in some problems, only one or two are required. Once a correct set of pi terms is obtained, any other set can be obtained by manipulation of the original set. Section 7. 06 common dimensionless groups in fluid mechanics. In section 7. 04 we learned that: the number of dimensional variables necessary to describe any problem in fluid mechanics is limited, the number of different dimensionless groups (pi terms) can be unlimited. If we consider compressible and incompressible flows, there are many geometric and dimensional variables that appear such as angles, surface tension, head loss, lift, drag, pressure, etc. A useful physical interpretation can be often given to dimensionless groups.