Does Pressure Equalize in Double Wall Steel Tanks with a Leak?

  • Thread starter Thread starter tosh382
  • Start date Start date
  • Tags Tags
    Tank
Click For Summary

Discussion Overview

The discussion revolves around the behavior of pressure in a double wall steel tank system when the inner tank begins to leak. Participants explore the implications of pressure equalization between the inner and outer tanks, considering factors such as tank volumes and the nature of the leak. The scope includes theoretical reasoning and conceptual clarification regarding pressure dynamics in this specific tank configuration.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions whether the volume between the inner and outer tank shells is 600 gallons or if it includes the inner tank, suggesting that this distinction is crucial for understanding pressure dynamics.
  • Another participant proposes that if the inner tank leaks, the pressure in the inner tank will decrease while the outer tank's pressure will increase, eventually leading to equalization at a lower pressure in the inner tank and a higher pressure in the outer tank.
  • There is a suggestion that the leak could act as a throttle valve, potentially affecting the overall pressure in the system.
  • A participant introduces the concept of an isentropic process for an ideal gas, proposing a relationship between pressure and volume, although this is contingent on specific assumptions about the gas behavior.

Areas of Agreement / Disagreement

Participants express differing views on the specifics of pressure equalization and the effects of the leak, indicating that multiple competing perspectives remain without a consensus on the final outcome.

Contextual Notes

Participants note limitations in the problem's formulation, including ambiguities regarding the initial conditions and the definitions of the tank volumes, which may affect the analysis of pressure behavior.

tosh382
Messages
1
Reaction score
0
I have a double wall steel tank system, where the inner sealed tank is 300 gallons and the outer sealed tank is 600 gallons.

If the inner tank holds 68 psig and begins to leak and the pressure goes out into the outer tank also, is it still 68 psig? If not, is it directly proportional, such that the pressure would become 34 psig?
 
Engineering news on Phys.org
The problem is ill-posed.

Is the volume between the inner and outer tank shells 600 gal, or does the 600 gal enclosed by the outer tank also include the inner tank?

What is the initial pressure between inner and outer tanks?


All else the same, pressures equilibrate.
 
Also the leak might work as a throttle valve and therefore, the overall pressure might be less. But basically the problem is Tank A (68 psig, 300 galons) and Tank B (0 psig, 300 gallons) are separated by a partition. What would be the overall pressure after removal of the partition?

Is this the problem?
 
tosh382 said:
I have a double wall steel tank system, where the inner sealed tank is 300 gallons and the outer sealed tank is 600 gallons.

If the inner tank holds 68 psig and begins to leak and the pressure goes out into the outer tank also, is it still 68 psig? If not, is it directly proportional, such that the pressure would become 34 psig?

If you have one tank (with air in it I presume) with a volume of 300 gallons at 68 psig sitting inside another tank with a volume of 600 gallons and 0 psig and the inner tank leaks, the pressure in the inner tank will not stay the same. It will decrease while the outer tank increases. Eventually they will equalize and be at the same pressure (inner tank lower, outer tank higher, from original pressures).

If you assume it is an ideal gas that undergoes an isentropic process the relationship will be Pv^k = constant where k is the ratio of specific heats of the air (typically 1.4).

CS
 

Similar threads

Replies
50
Views
8K
  • · Replies 26 ·
Replies
26
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
Replies
4
Views
3K
  • · Replies 39 ·
2
Replies
39
Views
16K
  • · Replies 27 ·
Replies
27
Views
11K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 52 ·
2
Replies
52
Views
8K
  • · Replies 15 ·
Replies
15
Views
3K
  • · Replies 3 ·
Replies
3
Views
8K