I don't know how much I can help but it seems we may be interested in the same subject but from a different aspect. I'm currently looking to model the effects of liquid holdup in low rate gas production wells and the consequent ability to choke wells. Current thinking is to use the Turner et Al equations to model the critical velocity at which liquid load-up occurs and the well starts to kill itself. The equations are only moderately useful (and not particularly accurate at very low rates) in that the real issue is that most operators don't want to choke the well. They normally want to flow or not flow - i.e. shut-in. What is really needed is a model that will indicate if the well will come back on it's own or will require lifting. That's my point of interest.
As you rightly point out. The issue relates to the well's ability to offload the already accumulated water in the well. If you assume that the well is balanced against it's THP then when the well is opened, provided it has THP, it should offload. However, in low rate wells, the ability of the reservoir to deliver gas at sufficient rate to overcome the weight of the existing fluid in the wellbore is the main issue. Primarily, I think, you will need to model the skin (pressure drop which the well has to overcome before it will flow).
If interested to discuss further - email at moscow01@hotmail.com





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