Stephan, I am not aware of an existing ORC model for TRNSYS. The one time that we needed to model one, we took a simplified overall efficiency approach. The cycle efficiency depended on some time dependent variables but we did not model the actual components of the cycle. About a year ago, a client approached us about writing a component-based cycle model but the project didn't proceed. As I think you have discovered, most (if not all) of the power producing components available use steam as the working fluid. They call various steam properties routines internally. It would not be all that difficult to change the models to call a property routine for some other working fluid. The real complication comes in writing or obtaining the property routine for that other fluid. The routine would have to be able to return all of the state properties (density, temperature, pressure, enthalpy, entropy, quality, etc.) based on knowing any two of those properties. Some years ago, there was a TRNSYS component written to transfer information between TRNSYS and a software tool called REFPROP (http://www.nist.gov/srd/nist23.cfm) which can return refrigerant properties of quite a few different fluids. Reviving that Type might be the simplest way to proceed. Kind regards, David On 2/2/2012 07:03, stephanlangbsc@aol.de 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 |