Some issues with Aspen for Coal
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In “Aspen for Coal”, I didn’t fully understand some parts of the mathematical model for the drying reaction of coal. The text states that “The Calculator block specifies the moisture content of the dried coal and calculates the corresponding conversion of coal to water”. In other words, is the moisture content of coal after it undergoes the drying reaction already known? Then what’s the point of establishing a mathematical model? Isn’t what we need the component data of the coal after drying? Moreover, the text mentions calculating the conversion factor conv for converting coal into water, but it isn’t shown in the results either? I’m quite confused about how to establish mathematical models; I would appreciate it if experienced teachers or friends could offer some guidance. Thank you~ Also, I’m not very familiar with some terms used in variable definition. For example, what does the \"variable\" column mean?
Variable means a variable (that is, a parameter that can change).
Various variables: Specific definitions can be found in the HELP section for detailed explanations
3# TOMMORROW Oh, thank you. What about the issue with the mathematical model? I mainly didn’t understand that part~
I think he has simplified the process of coal drying here by assuming that coal drying is a reaction of \"wet coal – dry coal + water\", with the stoichiometric coefficients being derived from the moisture data in the chemical analysis of coal. It’s more convenient to refer to the annotations for information on the various variables you mentioned.
I think the same way. The mathematical model he developed is meant to use wet coal to neutralize the moisture content in dry coal in order to calculate the conversion factor. I can’t remember the initial conditions clearly; the moisture content of dry coal is a known value, while I thought it was a value that needed to be calculated. But if the moisture content of the dry coal is known, why not simply enter 10 on the component properties page of DRY-REAC, instead of entering a temporary value of 1? Also, throughout the entire drying process, what we are concerned about is the flow rate of dry coal; is this flow rate value calculated using that mathematical model for conversion fractions? If not, then what is used as the basis for the calculation? 5# laipi*ao*n
“\"Why not simply enter 10 on the component properties page of DRY-REAC, and instead enter a temporary value of 1?\" I think it is done so that different types of coal can have their respective moisture content values automatically controlled through Fortran formulas; in other words, a model specific to each type of coal is used. “Is its flow value calculated using that mathematical model for converting fractions? I think so.