I am using Modelica to model the concentrations in a series of liquid tanks as multiple object is immersed through these tanks sequentially. An object "picks up" and drops off liquid as it proceeds Thus, these concentrations change constantly as many cycles of objects are processed through these tanks. I use an array to store the values of the different concentrations at these various tanks. Each tank is either a reagent tank or a rinse tank.

One aspect of the project that I am interested in is reversing the direction of the process, as the tanks are of 'palindrome' nature and can go forward and backwards. I tried implementing this in the code by reversing the concentration arrays, but I get the following error:

"[2] 12:33:08 Translation Notification
It was not possible to check the given initialization system for consistency symbolically, because the relevant equations are part of an algebraic loop. This is not supported yet."

I believe this has to do with Modelica not being able to handle sudden timed event changes in the equations. Is there a way to circumvent this issue? Would it be best to have two separate programs in which the second one takes in the concentration values from the first program, and uses those as initial conditions for the program that does the reverse direction?

Any help is appreciated! Thank you!