API 521 - Supercritical Fluid
API 521 - Supercritical Fluid
(OP)
API 521 Section 3.15.2.1.2 states that discharge areas for pressure relief on vessels containing "super-critical fluids, gases, or vapors" can be estimated using the equation provided. A) What is meant by super-critical? B) What sizing equation is used when the fluid is NOT super-critical? 3) Why doesn't the equation provided take into account any of the properties of the fluid? 4)The previous section states "the heat absorption equations listed in the following (?) are for..." Since there are no such equations in the following section, what is being referred to here?





RE: API 521 - Supercritical Fluid
RE: API 521 - Supercritical Fluid
In simple terms, its just a fancy way of saying a gas and keep people from saying the butane in the tank is a liquid be cause evryone knows butane is a liquid.....
RE: API 521 - Supercritical Fluid
Regards
RE: API 521 - Supercritical Fluid
RE: API 521 - Supercritical Fluid
Consider v<<vc and follow a constant spec vol process on a p-v diag as p decreases. Why won't liquid be the end point?
Regards
RE: API 521 - Supercritical Fluid
Here is my simple definition of a super criticle fluid. It has the molecular energy of gas, but it has physical properties of a liquid. So the molecules internal energy is very high and that is the worst case scenerio when trying to control the fluid.
The higher energy in gases is why we shy away from testing vessels with gases and use water instead.
RE: API 521 - Supercritical Fluid
Also, does anyone have any insights regarding the other questions?
RE: API 521 - Supercritical Fluid
Otherwise, I would try NIST
regards
RE: API 521 - Supercritical Fluid