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Avishek, There are a number of issues with the project that you sent. First, the absorption chiller that you specified has a 425 ton capacity while the collector has a 2m2 area. There is no pump in the hot water loop to set the flow rate so because the absorption chiller appears first in the component order, the flow rate in that loop is a constant 58000 kg/h. There is no weather data reading component attached to the solar collector. Second, the cooling water loop components (tower and pump) do not appear to be sized to match the absorption chiller. The pump's rated capacity is 1000 kg/h while the default cooling water flow rate for the chiller is 279000 kg/h. There is no weather data reading component attached to the cooling tower. Third, I am not clear on the intent of the chilled water loop. The chilled water from the absorption chiller is passing across the source side of a liquid to liquid heat exchanger (which would cool down the liquid on the other side of the heat exchanger). However, the other side of the heat exchanger is connected to the air coming out of an electrically fired unit heater. Air presumably cooled down by the heat exchanger is then returned to the unit heater but the heater control signal is set so that the unit heater is not allowed to turn off. Thermally I would guess that since there is no heat input into the air circulating through the unit heater and the absorption chiller is set to be constantly on the air is being driven to absolute zero, well beyond the range of applicability for the psychrometrics routine. When working with TRNSYS simulations it is vitally important to construct systems one component at a time. The procedure that I follow is to select an appropriate model from the library then open it and make certain that its parameters are set appropriately for the size of equipment that I intend to model. It is also important to click on the "more" button for the parameters and for the input initial (and constant) values so that I understand what information they are asking me to provide. Once I have a component in place, I connect its inputs and then use an online plotter to watch whatever outputs are appropriate (usually temperatures and flow rates). I often make a guess as to what I think I should see at the output of a component, then run the simulation and test whether I was right or wrong. Once I understand the output then I add another component. Inputs that are not connected stay constant throughout your simulation. I would recommend that you start by specifying only the absorption chiller in your system and send the temperature and flow rate of its three liquid streams to an online plotter. Set the chiller's control signal using a forcing function so that it is on or off only as a function of time. Once you understand the behavior of the model then you could add a solar collector with a constant flow rate and a weather file. However, do not yet connect the hot water output of the chiller to the input of the solar collector. Connect only the outlet of the solar collector to the input of the absorption chiller. Set a constant flow rate into the collector by specifying an input flow rate but do not connect the input. Change the size of the solar collector until it is providing you with the temperature and flow rate of water that is required by the absorption chiller that you selected. Regards, David On 2/3/2015 06:42, avishek ray wrote:
-- *************************** David BRADLEY Principal Thermal Energy Systems Specialists, LLC 22 North Carroll Street - suite 370 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 |