What happens if a negative pressure gradient is applied to a diffuser?

Click For Summary
A diffuser typically reduces fluid velocity by increasing the cross-sectional area, leading to an increase in static pressure according to Bernoulli's principle. Applying a negative pressure gradient by increasing inlet pressure over outlet pressure creates a paradox, as it forces flow through the diffuser. This action will continue until the output pressure adjusts to satisfy Bernoulli's equation. The discussion highlights the complexities of fluid dynamics and the implications of manipulating pressure gradients in diffusers. Understanding these principles is essential for addressing flow behavior in engineering applications.
ahog
Messages
4
Reaction score
1
A diffuser normally decreases the velocity by increasing the area. With assumption of an incrompressible flow, according to Bernoulli, the static pressure increases. What happens if one "forces" the flow through a diffuser by applying a bigger pressure on the inlet than on the outlet?
 
Engineering news on Phys.org
Welcome to PF.

You have hypothesised a paradoxical impossibility.
The flow will increase until the output pressure rises to the point where Bernoulli is satisfied.
 
  • Like
Likes russ_watters and ahog
Baluncore said:
Welcome to PF.

You have hypothesised a paradoxical impossibility.
The flow will increase until the output pressure rises to the point where Bernoulli is satisfied.
Thank you very much, i was really driving myself crazy...😂
 
Assume that a 100m long (probably irrelevant) train travelling at 30m/s, with a mass of 100.000 Kg passes next to a man/woman of 100 Kg standing still at 1 m away from the track. Since air is massively displaced by the train, creating like a small vacuum/low pressure area next to its surface, I reckon a certain pull may be applied to anything the train passes by, so in this case a person. My question is very simple: this pull can be quantified by a force. Is this force enough to pull the...

Similar threads

Replies
0
Views
1K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 45 ·
Replies
45
Views
5K
  • · Replies 31 ·
Replies
31
Views
4K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
1
Views
3K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 8 ·
Replies
8
Views
3K