Pressure at the boundary between two gas phases which are originally sepearted

AI Thread Summary
Determining the pressure at the boundary between two gas phases, such as compressed carbon dioxide and the atmosphere, can be complex due to differing pressures calculated using the ideal gas equation for each phase. The pressure at the boundary is not simply the average of the two but must consider the specific conditions and interactions at that interface. Regarding Pascal's Law, it does not apply in the same way to flowing fluids, as pressure is not uniform in such cases. Instead, pressure variations occur due to factors like velocity and flow dynamics. Understanding these principles is crucial for accurate pressure assessments in fluid dynamics.
eemmann
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Hi. I have got two questions...

1. How can we determine the pressure at the boundary of two gas phases (say, compressed carbon dioxide released from a can and the atmosphere) which are originally separated? If we apply the ideal gas equation on each of these two phases, different pressures will be obtained, how do we determine the the value of the pressure at the boundary??

2. The Pascal's Law states that "pressure exerted anywhere in a confined liquid is transmitted equally and undiminished in all directions throughout the liquid". I am wondering if such principle(same pressure at a point in all directions) still holds if the fluid is flowing?

Thanks.
 
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eemmann said:
Hi. I have got two questions...

1. How can we determine the pressure at the boundary of two gas phases (say, compressed carbon dioxide released from a can and the atmosphere) which are originally separated? If we apply the ideal gas equation on each of these two phases, different pressures will be obtained, how do we determine the the value of the pressure at the boundary??

2. The Pascal's Law states that "pressure exerted anywhere in a confined liquid is transmitted equally and undiminished in all directions throughout the liquid". I am wondering if such principle(same pressure at a point in all directions) still holds if the fluid is flowing?

Thanks.
With regard to the first question, what is being asked is not clear.

With regard to the 2nd question: No. In a flowing fluid, the pressure is not uniform.
 
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