3 replies to this topic

[Danish.Dynamo88]

When doing a mass balance on excel and adding in a recycle function excel produces a circular reference.

I tried a different approach using solver but it gave me a deficit of mass.

Any advice/ strategy would be immensely appreciated.

[Bobby Strain]

If you post your spreadsheet you might get better answers.

 

Bobby

[Francisco Angel]

Dear Danis.Dynamo88:

Your problem is like this:

 

Cell x = f ( Cell x)

 

Where f is a function, maybe in the form of a chain of cell dependencies, this is a circular reference. You can solve it using an auxiliary cell like this.

 

Cell x = f (Cell aux )

 

Cell aux must have the same value as x, for the problem to have the solution you are looking for. You can not link Cell x to Cell aux, because you would have a circular reference again. You have options like:

* Manually copying the value of Cell x to Cell aux in an iterative manner.

* Implement a script in VBA to copy the value of of Cell x to Cell aux, again in an iterative manner.

* Reformulate the problem to eliminate the circular reference, in this case you would be solving a slightly different problem, that may require to reformulate a portion of the sheet.

Best regards.

[Profe]

Hi Danish.

 

Attached I send send you an example for use the solver to iterate that I think you can use for recycle without use circular

 

Review it and try to apply this method. For instance use known mass for balance or fraction molar = 1 for objective and pressure or temperature for variable (changing value)

 

Good luck

Attached Files

•  Libro2.xlsx   338.65KB   112 downloads

Edited by Profe, 14 February 2017 - 08:06 AM.