Dear Ajinkya Pal

Please use the latest version of Matlab (V. 9.8)

Dear Ajinkya Pal,

Please increase the virtual memory of your PC or Laptop, to help you continue running the simulation and in the same time reduce the total time of analysis.

Hi Ajinkya Pal,

I recommend you to review data of optimization variables sent to hysys by Optimization Algorithm that you are using. Usually, Hysys crashes when wrong data is being used to fill hysys variables. For instance, sometimes wrong data (e.g. imaginary numbers) can be generated by optimization algorithms when wrong values of objective function are feeding the algorithm, how are you handling infeasible simulation results?. I mean, correct interconnecting data transfer between Algorithm and Hysys is a key step for better optimization performance.

Besides, I suggest you to use "try" & "catch" matlab statements to avoid a sudden stop of the optimization algorithm, think about this: try run hysys simulation with GA imported data, if an error is presented then catch and do the following - close or "kill" hysys procedure, reopen hysys simulation, do objective function value as "Penalty value" and GA can continue.

Also, I reccomend you follow the methology for optimization purposes described by Profesor Gade Pandu of National University of Singapore, same affilation of you, in his recent free paper:

https://www.mdpi.com/2227-9717/8/5/508/htm

Other reason for Hysys malfunction is feeding hysys variables with very long numbers, such as numbers with many decimals. Therefore I recommend you apply "Round(variable, #Decimals) Matlab function to feed shorter and more manageable numbers.

Finally, I recommend this NASGA II algorithm for optimization task: https://www.mathworks.com/matlabcentral/fileexchange/71609-real-coded-integer-handling-nsga-ii?s_tid=prof_contriblnk

I hope these tips are helpful.

Regards,

Andrés Abril