- #1

- 51

- 3

- TL;DR Summary
- viscous dissipation of mechanical energy into internal energy

imagine two flat plates, the upper one moving with speed v in the +z direction, the lower one is stationary

is the upper plate inserting work (per unit time) on the fluid system or the system exerting work on the plate?

or both? why they don't cancel each other e.g if the fluid is receiving work from the upper plate then its internal energy is increasing, but if the fluid exerts work too then the works cancel (?)

is the upper plate inserting work (per unit time) on the fluid system or the system exerting work on the plate?

or both? why they don't cancel each other e.g if the fluid is receiving work from the upper plate then its internal energy is increasing, but if the fluid exerts work too then the works cancel (?)