Regarding dynamic parameters
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When entering the kinetic parameters for powerlaw behavior, the pre-exponential factor needs to be converted in terms of units. For example, if the value given in the literature is in mol/(kgcat*h), Aspen will not accept this unit (in most reactors). I would like to know what the default unit for reaction rate in Aspen is: mol/(m3*s), or is it determined by the user’s own setting? Last time I saw a document that seemed to lean more towards the former; let’s discuss it. . .
It seems it’s in the ASPEN Chinese manual... Take a look; be sure not to get the units for the reaction order wrong. One of my professor’s graduate students made that mistake, and as a result all his work was in vain.
It seems that the parameter explanations in the manual are not detailed enough, especially for LHHV
I recently encountered a problem similar to the one mentioned by the original poster; I’m hoping experts can help solve it~~!
Depending on the standards you use and the unit basis for the duration, it is recommended that the original poster take a look at that translated 10.0 Chinese Aspen tutorial, which provides detailed explanations in relation to specified chemicals and reactions.
I have studied this issue; citing a translated version of an English literature source, Aspen requires the unit of kmols^(-1) m^(-3). I have carried out calculations myself and indeed it is the case. But when doing so, please note: depending on how the rate is expressed, if it is in terms of mole fraction, then K uses the same unit as mentioned above. For other quantities such as concentration or partial pressure, the rate expressions will also use the aforementioned units! !
I have studied this issue; citing a translated version of an English literature source, Aspen requires the unit of kmols^(-1) m^(-3). I have carried out calculations myself and indeed it is the case. But when doing so, please note: depending on how the rate is expressed, if it is in terms of mole fraction, then K uses the same unit as mentioned above. For other quantities such as concentration or partial pressure, the rate expressions will also use the aforementioned units! !
There are several types of concentration bases: Molarity, kmol/m3; Molality, mol/kg water; Partial pressure, Pa; Mass Concentration, kg/m3; Mole fraction, —; Mass fraction, —
The k unit is related to the rate basis: 1. Revc(vol) is in units of kmol per cubic meter per second, namely kmol/(m^3*s); 2. Cat(wt) is in units of kmol per kilogram per second, namely kmol/(kg*s)
You can check the help files; it’s explained very clearly there