In Example 9–6 we derive the equation for volumetric strain rate,

Write this as a word equation and discuss what happens to the volume of a fluid element as it moves around in a compressible fluid flow field (Fig. P9–25).

Fig. P9–25

Data from Example 6

Recall the volumetric strain rate, defined in Chap. 4. In Cartesian coordinates,

Show that volumetric strain rate is zero for incompressible flow. Discuss the physical interpretation of volumetric strain rate for incompressible and compressible flows.

Transcribed Image Text:

(1/V)(DV/Dt) = V.V.