How to calculate the change in gas pressure inside a closed container with temperature?
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In a sealed container, nitrogen is filled to a certain pressure P1; at this point the temperature is T1. Over time, the temperature of the gas inside the container changes to T2. How can the actual pressure P2 inside this sealed container be calculated? Please do not mention the formula PV=nRT; everyone knows that. What I want to calculate is a real pure gas. How can I model this using Aspen?
Either dynamic simulation can be used, or sensitivity analysis.
This post was last edited by arpcd on 2015-9-2 00:44. Aspen is a steady-state simulation software; tools like VMGSim are the more suitable options. But it seems like the original poster is too rigid. For Aspen, such problems should not be difficult to solve with a bit of thinking: set two streams with the same flow rate, for example 1 kmol/h or 1 Nm3/h. Set the initial conditions for the first stream (P1, T1), and set the temperature for the second stream (T2); assign an initial value to the pressure, then continuously change this P2 value until it is equal to the volumetric flow rate of the first stream. You can also use a controller for this purpose. . . I’m not familiar with Aspen, but I’m a bit more familiar with PROⅡ; the principle is the same in either case – it’s about turning a steady-state condition into a stable one. The key is to use one’s brain a lot. . .