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Shock load due to high pressure gas flowing into container

  1. Jul 21, 2012 #1
    Hello, I am new here so I apologize in advance if my question is not formatted as it should.

    I have an application where a large pressurized vessel is releasing part of its contents (gaseous) into an "empty" container (air), much smaller, that is at atmospheric pressure. I need to know if the initial shock of the gas (nothing reactive) from the vessel flowing into the container would rip the container apart or rip it from the vessel, so I need to calculate the force (or an equation for the force) due to the high pressure air rushing in.

    The vessel contains a gas (nothing reactive) at 150 psi absolute pressure (135 psig).
    The container into which it releases said gas is at 15 psi absolute pressure (0 psig).
    The orifice size is a circle of radius 2.
    The shape of the container is as follows:
    Cone going from 2" radius to 3-3/8" radius (4" dia to 7.5" dia)​
    Cylinder at 3-3/8" radius (7.5" dia pipe)​
    Cone going from 3-3/8" radius to 2" radius​
    The total height, orifice to bottom of container, is roughly 11"
    The volume of the container is roughly 0.17 cu. ft.
    Assume acceleration due to gravity is negligible.
    Assume the pressure drop in the large vessel is negligible (V_vessel >> V_container)

    Where do I start? Volumetric flow, pressure differential equation (meteorological), etc.

    Let me know if you need the surface area of the bottom and bottom taper of the vessel, or its "normal surface area" in the direction of the flow.

  2. jcsd
  3. Jul 21, 2012 #2


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    Shock waves can be created by the flow of a gas at sonic velocity through a restriction in a pipe. But those shock waves are never so large that they need to be taken into account in any stress analysis of the parts. So when you have a vessel dumping a gas into a container and resulting in a sudden pressure rise of the container, there is no need to consider any additional stresses caused by the gas other than the resulting internal pressure. Just determine the worst case pressure rise in the container and calculate stresses as if they are static.
  4. Jul 30, 2012 #3
    Thanks! And sorry for the delay :)
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