What is the difference between on and above?
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When simulating a tower, there is an option for where to place it: on the stage or above the stage. What is the difference between these two options? I appreciate your advice! ～
\"Above\" simply means above a certain object, at a higher position but without touching it; it does not imply being \"vertically above\" it. Example: The moon was above the trees in the east. At that time, the moon was already above the trees in the east. The antonym is below. Example: I saw the moon above the roof. I saw the moon moving above the roof. \"on\" means \"on top of...\", indicating mutual contact. Example: There’s a book on the desk. There is a book on the table. The antonym is beneath. For example: There’s a book on the desk. There is a book on the table.
\"On the stage\" refers to calculating the gas-liquid equilibrium starting from the feed tray, while \"above the stage\" means calculating it starting from the tray above the feed tray, which is one tray less than \"on the stage\".
Quite professional, I’ve learned something. Thank you
Thank you; I had only a vague understanding at first, but your explanation made it very clear.
“I disagree with the claim that there is one less element compared to on the stage; when considering the impact of feed flashing on calculations, various flashing conditions must also be taken into account, such as the gas-liquid load other than that from the feed. If the feed’s contribution is relatively small compared to other gas-liquid loads, then its impact on the results is also minimal； Furthermore, this option affects not only the calculation results but also the feed setting in special cases. This is a classic question that has been discussed before by HaiChuan as well. The links below lead to my discussions on other platforms with forum members; feel free to join in the discussion. http://bbs.hgbbs.net/viewthread.php?tid=106127&page=2#pid466643 http://bbs.hgbbs.net/viewthread.php?tid=98681&extra=&highlight=stage&page=1 This post was last edited by LTY on 2008-10-20 09:06]
I’ve gained a deeper understanding of this issue and have some insights; thank you!
The liquid portion enters above the feed tray and the vapor portion enters below it. :o The liquid portion is placed on the designated feed tray, while the vapor portion feeds the next higher tray in the column. I’m not quite sure how to understand these two sentences in PROII; could someone please translate them? Thank you. . . This post was last edited by realman1983 on 2008-10-22 at 14:07.]
Simply put, the first one is direct feeding. The second is flash feed. The difference is that after the first feed, the rising gas phase is cooled, causing disturbances at the feed inlet and affecting the plate efficiency. There is a throttle pressure-reducing valve before the second inlet; after entering the tower, adiabatic flashing occurs, with the gas phase going to the upper tray and the liquid phase going to the lower tray.
It seems like a question from a foreign language proficiency test. My understanding is that “above the feed tray” and “below the feed tray” refer to the fact that, on this tray, the liquid phase flows downward from the tray, while the gas phase moves upward beneath the tray. The second sentence refers to the upper tray; if the feed plate is numbered n, then the upper layer is numbered n-1, and the gas stream belongs to the n-1th tray. It’s not hard to understand, but it’s not easy to translate. Creating an example and comparing them separately will make things much clearer. This post was last edited by LTY on 2008-10-22 16:24]