Ventana software support forum

Hi everyone,

I am trying to model a gas station which has a delivery once a year (e.g. 20ML/year) and
consumption within the year (e.g 15ML/year). Since my delivery is discrete ( it only
occurs once a year), how I can mode it properly?
If I use "Pulse function", with time step equal to 0.25, at the end of the year, the
model consider delivery equal to 0.25*20=5ML, while in fact 20Ml has been delivered.

Many thanks in advance for your help.

If the time step for your model is in days, the following should work. Use the "ORDER NOW FLAG" to trigger the order.

Tony.


TIME BETWEEN ORDERS = 30
Units : Day

ORDER NOW FLAG = IF THEN ELSE ( Time Since Last Order
>= TIME BETWEEN ORDERS
, 1
, 0 )
Units : DMNL

RESET TIME SINCE LAST ORDER = order now flag
* Time Since Last Order
/ TIME STEP
Units : day/day

TIME SINCE LAST ORDER = INTEG ( TIME STEP / TIME STEP - reset time since last order , 0 )
Units : day