Hi Henk, On 03/04/12 01:52, Henk Fikkert wrote: > Hi John, > > thanks for your swift reply! > > The model development will at first aim at simulating the current > steam-cycle, and gradually include more detail on the equipment side. > I aim to model economizers, superheaters and radiative reactor > surfaces in deatail, but for the time being simple heaters, with just > a energy-rate will be ok. To understand and use ASCEND for this > purpose already is a big challenge for me.
OK this will be a great process to go through, some of these components are things that we haven't yet implemented, but I'd be keen to try to help out and expand our model library along the way. > > There will always be a minimal liquid load for the flash. Would it be > a problem if this weren't the case? I considered using the flash model > from the model library, but I also want to gain knowledge on what > ASCEND is about. As I plan to model the fire-side, the more chemical > part of our plant, this might be a future option. So we will assume that there is also some liquid available to be evaporated, and we will assume that the phases inside the flash are always in equilibrium, and for the moment, we will assume a single-component flash, with only water. > > I don't need the heat input, it's considered an adiabatic flash. I the > past I used ASPEN+, and sometimes used the flash model to include a > heatstream. Would this heat-stream be a problem? The flash is > operating at the turbine low-pressure side : ~0.1 bar. I don't know > the pressure drop conditions yet. We can start off without the heat input then add it later. I don't think it will be a problem. > > Another question : how could I use data from a DLL the best way. I do > have a chemical data DLL (HSC Chemistry) available, linked to a > thermo-chemical database. Is it hard to interface the functions (e.g. > H, S and Cp data , that's where the name originates from) with ASCEND?. You can see two examples of code that integrates thermo properties into ASCEND: http://freesteam.svn.sourceforge.net/viewvc/freesteam/trunk/ascend/freesteam_ascend.c?view=markup http://code.ascend4.org/viewvc/code/branches/fprops2/models/johnpye/fprops/asc_fprops.c?view=markup We haven't up to now done any integration with commercial thermo routines but it would be a good exercise to go through, and I'd be happy to try to help. Alternatively, if you know exactly what your need is then I can try to extend our current FPROPS efforts to include whatever it is. I have recently started work on adding support for 400+ species with the data given in Reid, Prausnitz & Poling, specifically with support for the Peng-Robinson EOS and 4-term cp0 polynomials. Cheers JP ------------------------------------------------------------------------------ Better than sec? Nothing is better than sec when it comes to monitoring Big Data applications. Try Boundary one-second resolution app monitoring today. Free. http://p.sf.net/sfu/Boundary-dev2dev _______________________________________________ Ascend-sim-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ascend-sim-users
