PROGRAMS for REFRIGERANT PROPERTY DATA

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1 ASEREPwin ASEREPfxl PROGRAMS for REFRIGERANT PROPERTY DATA REFLIBwin REFLIBfxl Rev

2 Page 2 Programs for Refrigerant Property Data 1 Introduction The Institute of Air Handling and Refrigeration Dresden (ILK) has been carrying out basic research into refrigerants for many years. One result of this work is a collection of powerful programs for calculation of the thermodynamic and transport properties of the various refrigerants. Especially for Windows applications, the specialists at ILK have developed a property data library "ASEREP" 1 and an interface module "REFLIB" 1, which are available in the form of DLLs (Dynamic Link Libraries). They can be integrated into application software and provide data on thermodynamic and transport properties for many important refrigerants. Additional special programs, so-called "add-ins", are similarly available to permit access to the property data libraries via MS EXCEL, also to users without programming knowledge. Operating systems: Windows XP/Vista/7/8 (32/64 bit). 2 The property data library "ASEREP" The property data library ASEREP provides precise property data for almost all currently significant refrigerants. It is upgraded regularly with the data of new refrigerants. The name ASEREP (ASERCOM REfrigerant Properties) is derived from the name of the Association of European Refrigeration Compressor Manufacturers - ASERCOM 2, which recommends the library as a standard program for property data calculations. ASEREP comprises a special software module ASEREP32.DLL/ ASEREP64.DLL, which contains the property data functions, and fluid files (*.ref) for numerous refrigerants. ASEREP supports the so-called ASERCOM Interface Definition for Refrigerant Properties Calculation. One particular advantage of the property data library is its high computing speed, which is revealed especially in the case of calculation-intensive programs. The ASEREP library is not a stand-alone program. However, it can be used for individual program developments. The resultant program structures are shown below as a diagram in Fig ILK Dresden, ASERCOM: Association of European Refrigeration Compressor Manufacturers

3 Page 3 Application User program Library ASEREP ASEREP32.DLL Fluid files R134a.ref R407C.ref... Rxyz.ref Fig. 1: Program structure for use of the ASEREP library (ASEREPwin) In order to be able to use the library, the user needs only information on the calling conventions of the functions imported from the DLL. 3 The module REFLIB REFLIB 1 (REFrigerant LIBraries) is an interface module in the form of a dynamic link library (REFLIB32.DLL/REFLIB64.DLL), which organises access to several external property data libraries (e.g. ASEREP 1 and CO2_LIB6 1 3 ). REFLIB ensures that the linked property data libraries are not activated until they are required (dynamic linking). The sole prerequisite is that the libraries must support the ASERCOM Interface Definition for Refrigerant Properties Calculation. The libraries can be linked and configured at run-time by means of a special dialog. The user decides which property data library is to be used for which refrigerant and which problem. In this way it is possible to combine the specific advantages of the individual property data libraries. REFLIB permits the creation of program structures similar to those shown in Fig. 2. Application Microsoft EXCEL Fig. 2: Interface REFLIB... Libraries ASEREP CO2_LIB Library... Program structure on the basis of REFLIB (REFLIBwin) 3 The standard configuration of REFLIB includes the libraries ASEREP and CO2_LIB!

4 Page 4 4 Add-ins for MS EXCEL Microsoft Excel offers facilities to import functions from DLLs. Such functions can be made available to the user in the form of so-called add-ins. The functions contained in the add-in are available in every EXCEL worksheet and are thus as simple to use as any other mathematical functions. ASEREP.xlam/.xla and REFLIB.xlam/.xla are two such EXCEL add-ins. As can be derived from their names, they permit access to the property data library ASEREP and the interface module REFLIB, respectively. They offer the user, via MS EXCEL, the full functionality of the connected property data libraries, without the need for special programming knowledge. Basic familiarity with the operations of MS EXCEL is already sufficient to be able to work efficiently with the property data libraries. The corresponding products ASEREPfxl and REFLIBfxl are available for MS EXCEL XP/ 2003/ 2007/ 2010/ 2013 (32/64 bit). 5 Property data functions ASEREP and REFLIB make available the following functions of thermodynamic and transport properties: 1. Bubble and dew point pressure: p = f(t) and p = f(t) 2. Bubble and dew point temperature: T = f(p) and T = f(p) 3. Specific liquid volume: v = f(t) 4. Pressure, vapour phase: p = f(v, T) 5. Specific volume, vapour phase: v = f(p, T) 6. Temperature, vapour phase: T = f(p, v), T = f(p, h) and T = f(p, s) 7. Specific enthalpy, liquid: h = f(t) 8. Specific enthalpy, vapour phase: h = f(v, T) and h = f(p, T) 9. Specific entropy, liquid: s = f(t) 10. Specific entropy, vapour phase: s = f(v, T) and s = f(p, T) 11. Specific heat capacity, liquid: c = f(t) 12. Spec. heat capacity, vapour phase (p=const.): c p = f(v, T) and c p = f(p, T) 13. Spec. heat capacity, vapour phase (v=const.): c v = f(v, T) and c v = f(p, T) 14. Isentropic exponent, vapour phase: = f(v, T) and = f(p, T) 15. Sound velocity, vapour phase: w = f(v, T) and w = f(p, T) 16. Heat conductivity, liquid: = f(t) 17. Heat conductivity, vapour phase: = f(p, T) 18. Dynamic viscosity, liquid: = f(t)

5 Page Dynamic viscosity, vapour phase: = f(p, T) 20. Surface tension: = f(t) 21. Characteristic Data (molar mass, critical temperature, critical pressure,...) 22. User defined refrigerant mixtures (dependent on the particular library) 6 Refrigerants The standard library ASEREP contains property data for the following refrigerants: 1. HFCs, FCs: R14, R23, R125, R134a, R152a, R227, R245fa, R227ea R404A, R407A, R407B, R407C, R407F, R410A, R417A, R422A, R422D, R427A, R507 (=R507A), R1234yf, 2. Hydrocarbons: R290 (propane), R600 (n-butane), R600a (isobutane), R1150 (ethene, ethylene), R1270 (propene, propylene) 3. HCFC, CFC 4 : R22, R123, R11, R12, R13, R13B1, R113, R114, R502, R Others: R717 (ammonia), R718 (water, simplified), RE170 (dimethyl ether), R723 5 (azeotrope R717+RE170) (other refrigerants on request) The refrigerants available in other libraries are to be taken from the corresponding documentation. Rev.: Address: Institut für Luft- und Kältetechnik ggmbh HB Kälte- und Wärmepumpentechnik Bertolt-Brecht-Allee 20 D Dresden +49-(0) : +49-(0) dietrich.vollmer@ilkdresden.de 4 The property data for CFC refrigerants are not covered by the ILK revision service. 5 Provisional refrigerant name

6 Page 6 Appendix: Current program versions Module Vers. Rev. Windows Comment 32bit 64bit ASEREPwin X X Revision of aserep32.dll ASEREPwin X New. For 64 bit applications. REFLIBwin X X Revision of reflib32.dll REFLIBwin X New. For 64 bit applications. ASEREPfxl_x X X For MS Excel 32 bit only. ASEREPfxl_x X New. For MS Excel 32/64 bit. REFLIBfxl_x X X For MS Excel 32 bit only. REFLIBfxl_x X New. For MS Excel 32/64 bit.

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