How to restrain yourself when doing aspen?
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I have used pro/ii before, but now I am learning aspen plus. I feel that there is a big difference between the two. Aspen seems to be difficult to converge.
Mainly the setting of the initial value and the setting of the iteration range, learning* Aspen feels that it is more difficult to converge when doing absorption, and the initial value requirements are relatively high, but other things feel fine, haha
What you said upstairs is correct, haha, but you can also set up the simultaneous equation method (EO), which is more suitable for solving problems involving optimization and circular logistics, and can accelerate convergence.
Could you please give me a detailed introduction on the 3rd floor?
If you want to understand this problem, you need to have a deep understanding of the algorithm. I can only give some simple explanations. Maybe the explanations are not correct. I hope experts can correct me! Some of the better algorithms, such as simultaneous correction method, homotopy iteration, etc., are very good in terms of calculation speed, but one problem that cannot be solved is the initial value problem, which often makes the initial value inaccurate and leads to non-convergence. If the convergence error is gradually reduced, the number of iterations can be increased to achieve convergence, but this is often not the case. There are currently two methods to solve this problem.: 1) Change the initial value. This requires chemical engineering knowledge, and you need to accurately estimate various initial values 2) Change the algorithm. Choose a specific algorithm for each model to achieve optimal convergence. The above two points are only theoretical. I have written a small information that can be used as a reference to guide the setting of the initial value. http://bbs.hcbbs.com/thread-430336-1-1.html You've made a fool of yourself and long for extra points! It’s almost time to enter third grade!
Convergence is related to many factors. I think the principles of pro and aspen are the same. As long as you have the right basics, you will be fine. If it doesn’t converge, just look at where the problem lies and then slowly adjust it!
As long as your parameters are set correctly, aspen is easier to converge than PROII. It only takes one run to converge or find the error and correct it. However, PROII requires multiple runs to know whether it can converge.
I think you need to read books on optimization design. After you have a certain understanding of different convergence speeds and condition requirements, you can just choose the corresponding algorithm in ASPEN or PROII. Otherwise, you can only try randomly, and the final result may not be correct. good luck~~
Thank you all experts. I have just started to learn. I installed the program just two days ago. What I am doing is a simulation of chemical absorption. It seems that I need to work on it. It seems to be very advanced.