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BCs assigned to side branches

Posted: Fri Aug 07, 2020 6:18 am
by masihbln
hello SV team . thanks for developing such powerful platform.
I have a model constructed from CT image, the model has few branches ,along with main arteries.
we know from papers that minor branches hardly affect hemodynamic status even if they are included in model.
my question concerns values which should be assigned to these minor branches.
my outlet BC for main branches are RCR and selected from inf of papers. but here is lack of inf. regarding the BC of minor side branches.
Threrefore, what kind and what value for BC , do you recommend for these few (4) minor side branches, in order to minimize the effects they have on flow field . (as if they are not included in model)
best regards,

Re: BCs assigned to side branches

Posted: Fri Aug 07, 2020 12:53 pm
by wgyang
I think you may use RCR for the side branches as you did for the main branches. Do you know how much flow streaming to those side branches relative to the main branches. If so, you can adjust resistance values to achieve target flow splits. Otherwise, one often assumes that the flow to each outlet is proportional to A^x, where A is the outlet area and x is usually 1 or some other values. Thus, resistance can be determined. Similarly, capacitance can be assigned in a similar way relating the capacitance to the vessel size. This estimation gives you rough values for BCs. You can make adjustments based on these values.

Re: BCs assigned to side branches

Posted: Sat Aug 08, 2020 12:35 pm
by masihbln
thanks for your helpful answer.
yes, you point to Murray's law. doesn't it make problems that the outlet BC type executed ( RCR and resistance) aren't identical?

Re: BCs assigned to side branches

Posted: Sat Aug 08, 2020 6:39 pm
by wgyang
I think you can use RCR for all outlets and determine the total resistance (Rp+Rd) using Murray's law like rules.