Safety Injection System

The system typically includes [fig is si.cdw]:

A, supposed unlimited, supply A of cold, weakly borated water, with constant properties {p,h,b}a ≡{pa, ha, ba},

The SI pumps B which deliver a volumetric flow specified by interpolator wvis(sec) from a moment sec_is specified as Lstis/sec;
full flow is supposed to be reached after a delay dsec_is = Lstis/dsec.
Actually, sec_is will be set by the protection system.

A small tank B representing the pumps volume

A large tank C of cold moderated borated water

A small additional tank D with higher boron and higher temperature insuring high concentration boron dilution

A volume E (one for each loop) simulating the transport effect of the SI lines injecting a mass flow wyisl into the node iyisl, specified as loop_l / Lstll / iysil in input.dat, of loop l

For the sake of model simplification, the primary "global pressure" is extended to all the SI tanks. Thus the flow is forced to be the same in all SI lines.

If the influence of boron transport mode in the tanks and the injection lines is critical, it would be more appropriate modeling them as a simple Lagrangian stack.