FloWorks intermittent 2 vessels at berth does not unload parallel

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pc neo asked Dec 6, '19 Mischa Spelt answered Dec 6, '19

FloWorks intermittent 2 vessels at berth does not unload parallel

@Mischa SpeltIn this model the vessels are unload at a berth when OGV is present. The berth is setup to allow for maximum 2 unloading points. The model runs well initially where both vessels unload at the same time when present at berth. However, at time 217 it is seen that only 1 vessel is unload at 1 time, while the other vessel is simply "on hold" or so it seems. When eventually the vessel that seems to be "on hold" emptied and left, then new vessels that arrives will again unload at the same time.

This sympton is intermittent as it occurs again at time 593. :(

Please advise on what cause the issue and how to overcome it.

The version of FloWorks that I used is FloWorks 19.2.1 with a patch given in

https://answers.flexsim.com/questions/75319/install-1924-give-error-on-floworks.html?childToView=75327#answer-75327

Software Version:

FlexSim 19.2.4

FloWorks berth

· 1

pc neo commented · Dec 06, 2019 at 06:11 AM

Ops I forgot to attached the sample model.

sample-model-unload-abnormality.fsmHere is the sample model.

0 ·

sample-model-unload-abnormality.fsm (2.5 MiB)

Answer 1 · 2019-12-06T08:36:00Z

Mischa Spelt answered Dec 6, '19

Hi,

Two of your loading arms have a max.capacity of 1500, but ShipBargeDischArm1 only has a max. capacity of 750.

It's important to note that our solver will try to find a stable solution. So if ShipBargeDischArm1 is connected first it gets a flow of 750; then when the second loading arm connects as well, we'll try not to interrupt its flow and give them both a flow of 750.

However, when the second barge discharge arm connects first, the maximum allowed flow is 1500. Then when the other loading arm connects, no capacity remains and it will have to wait for the first one to finish.

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