12.7.1. Organization of an .rgp File

The following is a functional example of a .rgp file. Note that specific values may be different from those provided by third-party material property databases.

Figure 12.11: Schematic of the .rgp File Contents is a schematic representation of the .rgp file organization. The .rgp file is divided into HEADER and DATA sections. The first section begins with the line $$$$HEADER in the .rgp file, and contains all the parameter information for each material found in the DATA section of the .rgp file. The DATA section begins with the line $$$$DATA and contains parameter, superheat and saturation information for a given material. Within both of these major sections, all of the available materials are identified by an access key of the type $$$<component>, where <component> is the name of the material. This is also the name that you will see when selecting a material from CFX-Pre. The purpose of the HEADER section is to enable quick access to material information from CFX-Pre. Information on the order in which the property information is written to the .rgp file is available in Real Gas Property (RGP) File Contents.

Figure 12.11: Schematic of the .rgp File Contents

12.7.1.1. Detailed .rgp File Format

                 Type            Description
                 ----            -----------
$$$$HEADER
See NOTES 1 and 2
$$$$DATA
$$$<component>   character*8     (key into the .rgp file see NOTE 3)
   nn            integer         (this line is ignored in CFX)
$$PARAM                          See NOTE 4
   nn            integer         (number of parameters)
DESCRIPTION
aa               character*50    (description of the material)
NAME
aa               character*8     (material name, same as $$$<component>)
INDEX
aa               character*50    (index into clients RGDB program)
MODEL
   nn            integer         (level of property info available 1,2,or 3)
UNITS
   nn            integer         (unit system of 1,2,3,4 or 5)
PMIN_SUPERHEAT                   See NOTE  5
   rr            real
PMAX_SUPERHEAT
   rr            real
TMIN_SUPERHEAT
   rr            real
TMAX_SUPERHEAT
   rr            real
TMIN_SATURATION                  See NOTE 6
   rr            real
TMAX_SATURATION
   rr            real
SUPERCOOLING
   rr            real            (supercooling level in superheat tables)
P_CRITICAL
   rr            real
P_TRIPLE                         See NOTE 7
   rr            real
T_CRITICAL
   rr            real
T_TRIPLE
   rr            real
GAS_CONSTANT
rr               real
TABLE_1                          See NOTE 8
   nt np         integer
TABLE_2
   nt np         integer
TABLE_3
   nt np         integer
TABLE_4
   nt np         integer
TABLE_5
   nt np         integer
TABLE_6
   nt np         integer
TABLE_7
   nt np         integer
TABLE_8                          See NOTE 9
   nt np         integer
TABLE_9
   nt np         integer
SAT_TABLE
npsat nmaxp1 nmaxp2   integer
$$SUPER_TABLE
   nn            integer         (number of superheat tables, nn = 9)

(The following is repeated for each superheat table, currently at 9. This section relates to Figure 12.7: Representation of Superheat Tables Associated with a Material.)

$TABLE_nn
   nt np         integer         (size of superheat arrays, See NOTE 10)
write (iunit,*) (t(i),i=1,nt)              |all following real
write (iunit,*) (p(i),i=1,np)              |
write (iunit,*) ((phi(i,j),i=1,nt),j=1,np) |
write (iunit,*) (tsat(i),i=1,np)           |
write (iunit,*) (phisat(i),i=1,np)         |

(This section writes out the saturation information described by Figure 12.10: Representation of a Saturation Table Associated with a Given Material)

$$SAT_TABLE
npsat nmaxp1 nmaxp2          integer       (size of saturation arrays, see NOTE 11)
do j=1,nmaxp1                    |all following real
write(iunit,*) (prop1(i,j),i=1,npsat)      |
do k=1,2                         |
do j=1,nmaxp2                    |j=1 loop writes sat. liquid data
write(iunit,*) (prop2(i,j,k),i=1,npsat)    |j=2 loop writes sat. vapour data

Notes:

Information between $$$$HEADER and $$$$DATA is a "stripped down" version of all the property information following the $$$$DATA header. The $$$$DATA section of the .rgp file contains all of the property information relative to the material. This may become a very large file. The $$$$HEADER was added to the top of the .rgp file to enable rapid selection of materials. CFX-Pre reads in and lists this information for you during selection of a material.
The $$$$HEADER section contains everything that is in the $$$$DATA section for a given material except data following the $$SUPER_TABLE and $$SAT_TABLE headers.
$$$<component> must be an 8 character or less name identifying the material in the .rgp file. For example, for refrigerant , the key may read $$$R134A so that the material can be easily identified in the .rgp file.
The $$PARAM parameters may be listed in any order.
The parameters PMIN_SUPERHEAT, PMAX_SUPERHEAT, TMIN_SUPERHEAT, and TMAX_SUPERHEAT indicate the limits on the superheat tables. All superheat tables are built as functions of pressure and temperature because most users are able to estimate the pressure and temperature limits in their processes. Supercooling can be easily built into these tables if the equations of state enable it.
The parameters TMIN_SATURATION and TMAX_SATURATION indicate the limits for building the saturation tables. The limits should cover the range over which wetness is expected in the solution. The saturation properties should be written to the .rgp file, in equal increments of pressure, starting at TMIN_SATURATION and ending at TMAX_SATURATION.
The parameters P_TRIPLE, P_CRITICAL, T_TRIPLE and T_CRITICAL refer to the pressure and temperature triple and critical point values for the substance. The critical pressure and temperature must be supplied to the flow solver and, therefore, must be accurate. If they are not, then the table interpolation will not work correctly.
The GAS_CONSTANT for the pure fluid should be supplied and is required if the fluid is to be used in a multi-component fluid calculation.
The parameters TABLE_1, TABLE_2, TABLE_3, TABLE_4, TABLE_5, TABLE_6, TABLE_7, TABLE_8 and TABLE_9 refer to the size of the superheat tables for materials found in the $$SUPER_TABLE section. The parameter SAT_TABLE refers to the size of the saturation table for a material found in the $$SAT_TABLE section.
The superheat tables 8 and 9 contain information on molecular (dynamic) viscosity and thermal conductivity, respectively. Note that these tables are not required if they are set as constants or CEL expressions in CFX-Pre. This allows the omission of these tables in the .rgp file if superheat information for these transport properties (as functions of pressure and temperature) is unknown.
The order in which the superheat tables is written to the .rgp file is the same as the order shown in Real Gas Property (RGP) File Contents. For details, see Real Gas Property (RGP) File Contents.
The values for nmaxp1 and nmaxp2 are 4 and 9, respectively. The integer nmaxp1 refers to the number of single valued properties in the saturation tables, and nmaxp2 to the number of dual valued properties in the saturation tables. The order that the saturation tables are written to the .rgp file is the same as the order shown in the Real Gas Property (RGP) File Contents. For details, see Real Gas Property (RGP) File Contents. For the dual valued properties, the saturated liquid properties are written first (j=1) and the saturated vapor properties are written last (j=2) to the .rgp file.

12.7.1.2. Example .rgp File

$$$$HEADER 
$$$R134A
1 
$$PARAM 
26 
DESCRIPTION
Refrigerant R134a from NIST 
NAME 
R134A
INDEX 
R134A
MODEL 
2 
UNITS 
1 
PMIN_SUPERHEAT 
55000.00000000000 
PMAX_SUPERHEAT 
400000.0000000000 
TMIN_SUPERHEAT 
240.0000000000000 
TMAX_SUPERHEAT 
400.0000000000000 
TMIN_SATURATION 
240.0000000000000 
TMAX_SATURATION 
350.0000000000000 
SUPERCOOLING 
0.0000000000000000E+00 
P_CRITICAL 
405928.0E+3   
P_TRIPLE 
0.0000000
T_CRITICAL 
374.21
T_TRIPLE 
169.85 
TABLE_1 
5 5 
TABLE_2 
5 5 
TABLE_3 
5 5
TABLE_4 
5 5 
TABLE_5 
5 5 
TABLE_6 
5 5 
TABLE_7 
5 5 
TABLE_8 
5 5 
TABLE_9 
5 5 
SAT_TABLE 
5 4 9 
$$$$DATA 
$$$R134A
1 
$$PARAM 
26 
DESCRIPTION 
 Refrigerant R134a from NIST 
NAME 
R134A 
INDEX 
R134A 
MODEL 
2 
UNITS 
1 
PMIN_SUPERHEAT 
55000.00000000000 
PMAX_SUPERHEAT 
400000.0000000000 
TMIN_SUPERHEAT 
240.0000000000000 
TMAX_SUPERHEAT 
400.0000000000000 
TMIN_SATURATION 
240.0000000000000 
TMAX_SATURATION 
350.0000000000000 
SUPERCOOLING 
0.0000000000000000E+00 
P_CRITICAL 
405928.0E+3   
P_TRIPLE 
0.00000000
T_CRITICAL 
374.21
T_TRIPLE 
169.85 
TABLE_1 
5 5 
TABLE_2 
5 5 
TABLE_3 
5 5 
TABLE_4 
5 5 
TABLE_5 
5 5 
TABLE_6 
5 5 
TABLE_7 
5 5 
TABLE_8 
5 5 
TABLE_9 
5 5 
SAT_TABLE 
5 4 9
$$SUPER_TABLE 
9 
$TABLE_1 
5 5 
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   380537.4694438053          411338.2663531548          444977.3409773413
   481319.1776109927          520216.5694145825          389653.7412125674
   409809.2455431806          443799.3654908382          480400.4939131565
   519497.1970340972          397134.4582379403          408220.8885809304
   442595.4896125616          479470.0507244235          518772.4705830857
   402478.8117714382          406565.3815292667          441363.8343756341
   478527.3570462614          518042.2612321422          406650.5418732642
   406650.5418732642          440102.2828142202          477571.8870479560
   517306.4350445317
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   376541.6333194062          389653.7412125674          397134.4582379403
   402478.8117714382          406650.5418732642
$TABLE_2
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   146.0231331684759          157.8078814382528          168.5506303571756
   178.5170722927099          187.8737728104760          147.0869026517344
   155.2427165817653          166.8523505651282          177.3642207508735
   187.0763724397798          147.8329014568262          152.5632728477825
   165.1148711540457          176.1977255190386          186.2743889887011
   147.9104560214784          149.7535601390501          163.3352394640403
   175.0170180126285          185.4677211216712          147.6607838596043
   147.6607838596043          161.5101241729302          173.8214905237701
   184.6562641923786
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   144.3034887320350          147.0869026517344          147.8329014568262
   147.9104560214784          147.6607838596043
$TABLE_3
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   0.3481914037990427         0.4095738848363432         0.4702915495291079
   0.5305832630019515         0.5905860753062941         0.1402248442644343
   0.1561641066947830         0.1807449135220719         0.2048688905909286
   0.2286916876895624         8.9273098371410883E-02     444320344302E-02
   0.1107157321741076         0.1261131151219874         0.1411960889105597
   6.5633087958005529E-02     6.7151770525718760E-02     7.9166190580894386E-02
   9.0648541948697259E-02     0.1018021936800781         5.1900452073168755E-02
   5.1900452073168755E-02     6.1203439903817498E-02     7.0470885355410795E-02
   7.9394150509035255E-02
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   0.3397008120139503         0.1402248442644343         8.9273098371410883E-02
   6.5633087958005529E-02     5.1900452073168755E-02
$TABLE_4
   5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   644.8541874954598          719.7151797641214          790.5095338665236
   857.2366695715677          919.8970271275263          674.7791960407488
   721.6690087704523          792.3443057727616          858.9628531024553
   921.5203908806476          698.8825060917976          723.6988581975571
   794.2197800381258          860.7115954107751          923.1563593500967
   716.9720727393429          725.8148416296926          796.1389707941393
   862.4838781958006          924.8052629190319          731.8370306406068
   731.8370306406068          798.1052760769886          864.2807537481988
   926.4674455748727
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   634.2715599484291          674.7791960407488          698.8825060917976
   716.9720727393429          731.8370306406068
$TABLE_5
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   733.5432454120784          806.0266427729431          875.3572680256013
   941.1190584653727          1003.111496904734          773.6370689985604
   816.3711389524509          882.8108960718668          946.7561020285661
   1007.512627818587          807.0628915610768          827.9980795292242
   890.7840080089826          952.6232673331618          1012.020341520216
   834.4867573220491          841.2008081815245          899.3408892587429
   958.7368554939568          1016.639020749522          858.8621950799120
   858.8621950799120          908.5575294975291          965.1148207606369
   1021.373299533599
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   723.4007165554241          773.6370689985604          807.0628915610768
   834.4867573220491          858.8621950799120
$TABLE_6
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
  -154611.9428101669         -132557.4464307218         -115997.3804840207
  -103111.8528686964         -92801.69633261529         -959671.2544114459
  -873595.5996881851         -764854.3591592711         -680011.5179211511
  -612056.5815781737         -2374639.983863590         -2262401.182121443
  -1982996.713344134         -1763666.875581090         -1587621.548245155
  -4363498.860521937         -4291069.408039705         -3768294.493979145
  -3353439.511168068         -3019297.561697437         -6897297.389986640
  -6897297.389986640         -6117240.959939656         -5448329.203176694
  -4906781.742740840
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
  -158218.3298083634         -959671.2544114459         -2374639.983863590
  -4363498.860521937         -6897297.389986640
$TABLE_7
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   1786.030158361605          1904.585719752846          2016.779512855124
   2123.714780772325          2226.113661461630          1748.483241728080
   1823.905112007991          1937.275071424368          2044.975937996867
   2147.900948384664          1740.481415370240          1781.062492767768
   1895.721351626920          2004.229786438356          2107.697911720815
   1735.932309549977          1750.655644805153          1866.736275194941
   1976.098388594144          2080.127578672003          1732.877658407725
   1732.877658407725          1844.072019825660          1954.338672102516
   2058.947921108171
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   1769.188083636742          1748.483241728080          1740.481415370240
   1735.932309549977          1732.877658407725
$TABLE_8
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   9.4859076076546339E-06     1.1098072605476093E-05     1.2682727526284134E-05
   1.4225406873221409E-05     1.5718844908709814E-05     1.0113426130489583E-05
   1.1128384712488209E-05     1.2707428862857411E-05     1.4246015436604838E-05
   1.5736277818145713E-05     1.0622849104772714E-05     1.1161623164463395E-05
   1.2733802630234965E-05     1.4267707066828921E-05     1.5754472822231917E-05
   1.1006164112931968E-05     1.1198285735280963E-05     1.2761997824348757E-05
   1.4290540551654799E-05     1.5773456592676736E-05     1.1321670531250205E-05
   1.1321670531250205E-05     1.2792178337213511E-05     1.4314589371365448E-05
   1.5793272119540815E-05
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   9.2638729380455867E-06     1.0113426130489583E-05     1.0622849104772714E-05
   1.1006164112931968E-05     1.1321670531250205E-05
$TABLE_9
      5      5
   240.0000000000000          280.0000000000000          320.0000000000000
   360.0000000000000          400.0000000000000
   55000.00000000000          141250.0000000000          227500.0000000000
   313750.0000000000          400000.0000000000
   8.7318132315962922E-03     1.2367010749671227E-02     1.5479028969457832E-02
   1.8065003454933646E-02     2.0123880410625419E-02     1.0144646731520802E-02
   1.2375365154798446E-02     1.5478277206731493E-02     1.8061024664563677E-02
   2.0119085407073307E-02     1.1241534315205219E-02     1.2399427073087721E-02
   1.5485543810413213E-02     1.8061449100116474E-02     2.0116675809444373E-02
   1.2033532782386015E-02     1.2438788590707257E-02     1.5500573740125312E-02
   1.8066241345977847E-02     2.0116840814255434E-02     1.2665788438301477E-02
   1.2665788438301477E-02     1.5523214978202122E-02     1.8075268343013946E-02
   2.0119597534766078E-02
   234.5147959861216          254.6474401194407          266.4385386783982
   275.1224493134379          282.1192618430768
   8.1928902502712009E-03     1.0144646731520802E-02     1.1241534315205219E-02
   1.2033532782386015E-02     1.2665788438301477E-02
$$SAT_TABLE
      5      4      9
   72429.02057212396          669962.0863334293          1267495.152094735
   1865028.217856040          2462561.283617346
   239.9999762675480          298.3735220799146          321.5184369582214
   337.4761886205648          349.9999999385916
   0.0000000000000000E+00     0.0000000000000000E+00     0.0000000000000000E+00
   0.0000000000000000E+00     0.0000000000000000E+00
   0.0000000000000000E+00     0.0000000000000000E+00     0.0000000000000000E+00
   0.0000000000000000E+00     0.0000000000000000E+00
   157792.0768617229          234423.4028017849          268281.8836128900
   293391.1384832433          314607.4539245256
   1226.028409346856          1411.621580596332          1538.623093445163
   1688.584812454093          1901.162632743923
   1394.714486693549          1204.132429873541          1105.717252974825
   1023.909256983076          947.2617335591748
   7.3133047353247582E-06     1.5554466347974513E-05     2.3546196865974526E-05
   3.4054173679783401E-05     4.9653987218547186E-05
   836.0313698668695          1119.425611702024          1226.996801517600
   1301.491841955899          1361.442808503099
   1087.583619605917          1180.740355522880          1205.127882782043
   1215.472691163284          1218.190684502114
   0.0000000000000000E+00     0.0000000000000000E+00     0.0000000000000000E+00
   0.0000000000000000E+00     0.0000000000000000E+00
   4.5254108276952397E-04     2.0762809729902491E-04     1.5172962190515123E-04
   1.1920087721741867E-04     9.5575862436921458E-05
   0.1106897637097442         8.1042418175005723E-02     6.9512380598733353E-02
   6.1769627812551062E-02     5.5819411652293066E-02
   380136.7395374610          415734.4668987678          426586.7644804174
   431942.8510520858          434298.6702392859
   736.4416185000921          926.5982109988553          1070.936300636404
   1242.721436965689          1480.769140200031
   3.808368423257648          32.02662176918217          61.85130414931603
   94.90868505077478          132.4954540908795
   5.4108323518481296E-05     5.6676277290207862E-05     6.5936536523112708E-05
   7.9426352920085037E-05     9.9732676665902821E-05
   1762.467546546392          1727.090336441192          1719.363218938642
   1712.044400273131          1703.417712356647
   645.2669936904850          767.7650176481674          824.1454305224304
   868.8335090051181          909.2881576124906
   145.2336985804320          145.9254060428890          140.3837459659026
   134.1949902861215          127.7833214614285
   9.4933329019507708E-06     1.2087890198389884E-05     1.3328835395482605E-05
   1.4417814786729988E-05     1.5601940814775012E-05
   8.7357640893468182E-03     1.4138793457254478E-02     1.6414352714865677E-02
   1.8434500108658915E-02     2.0797428027421110E-02

Note: If you want to use the conditions above, copy the text and paste it into a text editor, taking care to match the formatting exactly, and save it as a .rgp file. In CFX-Pre, create a new material that refers to this .rgp file. For details, see Table in the CFX-Pre User's Guide. Note that the above example, with only a 5x5 table, does not provide sufficient resolution to produce meaningful results.