How is the discharge temperature calculated under thermal expansion conditions?
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This post was last edited by longkui1990 on 2018-8-10 at 16:58. I may not have expressed myself clearly before, so I’ve edited it again. For example, a tank is filled with p-xylene at 30°C and 20 barg. Now, the tank is gradually heated; we need to find the temperature at which the pressure inside the tank reaches 30 barg. Thank you O(∩_∩)O haha~
Saturation temperature at reduced pressure.
It’s just the liquid expanding; it hasn’t reached the point of vaporization yet
I wonder what the mass flow rate of xylene in your normal pipeline is? With the flow rate of 10,000 kg that I assumed, and after supplying 1 MW of heat, the operating temperature increased from 30°C to 205°C; however, the phase remained fully liquid. The discharge temperature during discharge can be taken as the operating temperature of 205°C℃ ； This is just a hypothesis of mine; under normal operating conditions, the heat capacity of xylene is 1.725 kJ/Kg·°C, and its latent heat of vaporization is 230 kJ/kg. You can calculate whether the medium will vaporize or partially vaporize after heat is applied. If a gas phase is formed, the corresponding discharge temperature at the discharge pressure can be calculated using the ideal gas law ；
I didn’t explain it clearly before; I’ve updated the post. Please take another look, thank you! O(∩_∩)O~
I didn’t explain it clearly before; I’ve updated the post. Please take another look, thank you! O(∩_∩)O
This is difficult to calculate, as it involves the thermal expansion of pipelines or equipment as well as that of the materials. Since pressure increases rapidly with rising temperature, it can be assumed that the temperature at the time of release is the temperature of the material, 30.
20barg p-xylene storage tanks are also very rare.
In reality, it is a pipe with valves at both ends; for simplicity’s sake, let’s assume that both ends have been cut off
This post was last edited by arpcd on 2018-8-13 at 09:54: https://bbs.hcbbs.com/thread-995357-1-1.html. You can refer to this post; the specific calculations are provided in the post on page 5. There is an issue with the way your question is phrased – the word \"closed\" is extremely important in this context. . . Even a temperature rise of just 1°C in a closed pipeline can result in an extremely high increase in pressure. . . . Be careful. .