Or maybe it’s __Mekanizmalar__ – as in upper-left & lower-right corners.

Actually, it says in the lower-left corner … but it’s so tiny I can’t read it for certain.

Showing how the speed of the flow of gas increases with distance along the nozzle _all the way_ along it – both where it’s _con_-vergent & where it’s _di_-vergent. Subsonic flow has increasing speed with narrowing, & supersonic with widening; flow is exactly sonic at the throat: the flow, by its very nature in such a nozzle, ‘adjusts itself’ to bring this about.

It’s a pretty ‘robust’ effect, aswell. In the elementary theory of this it’s assumed that the flow has negligible component perpendicular to the axis of the nozzle, ie that the narrowing & widening are extremely gradual; but in-practice it’s really not particularly necessary for that to be so … which is very fortunate for the construction of real ones of these … although by reason of it the precise particular values of pressure & velocity distribution with length probably depart somewhat from those calculated from the elementary theory.

I’ve never actually seen, though, a full theory of de Laval nozzle that takes normal-to-axis component of velocity into account, & I wonder whether anyone knows aught of that. I would imagine such a theory would be _a lot_ more complicated … & for departures from the results of the elementary theory that might not even be allthat large.

Unknown to whom it’s attributable.

Or maybe it’s __Mekanizmalar__ – as in upper-left & lower-right corners.

Actually, it says in the lower-left corner … but it’s so tiny I can’t read it for certain.

Showing how the speed of the flow of gas increases with distance along the nozzle _all the way_ along it – both where it’s _con_-vergent & where it’s _di_-vergent. Subsonic flow has increasing speed with narrowing, & supersonic with widening; flow is exactly sonic at the throat: the flow, by its very nature in such a nozzle, ‘adjusts itself’ to bring this about.

It’s a pretty ‘robust’ effect, aswell. In the elementary theory of this it’s assumed that the flow has negligible component perpendicular to the axis of the nozzle, ie that the narrowing & widening are extremely gradual; but in-practice it’s really not particularly necessary for that to be so … which is very fortunate for the construction of real ones of these … although by reason of it the precise particular values of pressure & velocity distribution with length probably depart somewhat from those calculated from the elementary theory.

I’ve never actually seen, though, a full theory of de Laval nozzle that takes normal-to-axis component of velocity into account, & I wonder whether anyone knows aught of that. I would imagine such a theory would be _a lot_ more complicated … & for departures from the results of the elementary theory that might not even be allthat large.

That’s a well hidden “watermark”. Right at the choke-point.