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Alexandros, 1. Type 107 and Type680 use a normalized catalog data which has limited values for Inlet Hot Water Temperature (from 108.89 (C) to 116.11 (C)), Entering Cooling Water Temperature (from 26.667 (C) to 32.222 (C)), Chilled Water Set point (from 5.556 (C)to 10.000 (C)). Ιf we use values outside this range, do we get wrong results?possibly. As it mentions in the documentation the components can interpolate within the data range given but they cannot extrapolate beyond the range. You'll get a notice as to how much of the time the components called the data files outside the range. If it happens rarely then I would not worry about the consequences. If it is happening all the time then the system needs to be better controlled or alternative data (with a wider range) is needed. 2. Τhe energy is discharged into the cooling water stream. If we want energy rejection to be done in the air, can we achieve it by changing the value of cp?I would not recommend doing so. Since the COP of the device is looked up from a data file, the effectiveness of the rejection heat exchanger is built-in to the performance data file. If the data comes from a machine that rejects energy to a water stream then the effectiveness built into the COP is that of a brine to water heat exchanger. A brine to air heat exchanger would presumably have a different effectiveness and therefore a different COP. In most applications that I have seen the cooling water stream goes to a cooling tower where the energy us then rejected to the air. If you have a device that rejects directly to air I would try very hard to get its performance data and then yes, change the Cp of the rejection stream. If you have a device that rejects to a water stream and then to a cooling tower I would model it as such. 3. Which working pair ( LiBr-H2O, H2O-NH3 ) is it used in the data file? Ηow can we study the effect of the concentration in the chilled power?I do not recall what brine was used in the example machine. If I had to guess, I would say that it was LiBr-H2O. You cannot examine the effect of the brine concentration on performance because performance is read from a data file. If you have more than one data file (one for a high concentration and one for a lower concentration) then you could examine such a modification in the context of the system. 4. The single effect hot water fired absorption chiller is used to solve energy balances between hot water, cooling water, chilled water, auxiliary electrical power. A more detailed analysis is it possible?No, not really because this is a catalog data lookup table model. You'd need to find (or write) a first principals model of the device if you want to do a more detailed analysis. kind regards, David -- *************************** David BRADLEY Principal Thermal Energy Systems Specialists, LLC 3 North Pinckney Street - suite 202 Madison, WI 53703 USA P:+1.608.274.2577 F:+1.608.278.1475 d.bradley@tess-inc.com http://www.tess-inc.com http://www.trnsys.com |