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MAPDL convection load with variable film coefficient and bulk temperature

    • Francesco Miccoli
      Subscriber

      Hello everyone,

      I am trying to implement in Ansys MAPDL a convection load on a named selection (curve, axis-symmetrical problem). The convection I have is defined by a TEMP (surface temperature) and X (coordinate) variable film coefficient and an X varibale bulk temperature. So far I came up with:

      *dim,bartz,TABLE,50,61,X,TEMP
      *taxis,bartz(1),1,... (where ... represent all the value composing the X vector)
      *taxis,bartz(1),2,... (where ... represent all the value composing the TEMP vector)
      bartz(1,1) = ...
      ...
      bartz(1,61) = ...
      ...
      bartz(50,61)= ...
       
      *dim,bulk,TABLE,50,X
      *taxis,bulk(1),1,... (where ... represent all the value composing the X vector)
      bulk(1) = ...
      ...
      bulk(50) = ...
      SF,name_of_selection,conv,%bartz%,%bulk%
       
      but even though the simulation runs without errors the results I obtain do not make sense. What am I doing wrong?
      Thanks in advance, Francesco
       
    • Chandra Sekaran
      Ansys Employee

      One suggestion is to go into the postprocessor Post1, do SET command to bring in a result set at a particular time point. Then display / list the convection loads. This will show the actual values used at that time point. This will be good way to check if you got what you intended.

      • Francesco Miccoli
        Subscriber

        Thank you for the reply. Unfortunately the results still do not make sense.
        Consider that the defined film coefficient I defined (bartz) has a peak for a value of X of around 0.5 of the total lenght, the same goes for the bulk temperature (bulk). With this input data I would expect the peak temperature to be at around 0.5 of the lenght and drop significantly after that, but the result I get is very incosistent with this. For this reason I think there is some problem with the definition of either the loads or of the TABLEs.

    • Chandra Sekaran
      Ansys Employee

      Can you confirm that the listing of the boundary conditions at a time point in Post1, shows that the film coeff and bulk temperature are applied as per the table?

       

    • dlooman
      Ansys Employee

      It's definitely tricky to do.  It's helpful to cut and paste (or /input) your table array into the input window in the APDL gui and then examine it with Parameters (top toolbar): Array Parameters> Define/Edit...

      Here's input for a 4d array that worked.

      *dim,hc_vals,tab4,2,2,2,2,x,y,z,time
      *taxis,hc_vals(1),1,0,1
      *taxis,hc_vals(1),2,0,1
      *taxis,hc_vals(1),3,0,1
      *taxis,hc_vals(1),4,0,1
       
      ! Time 0 values
      hc_vals(1,1,1,1)=1,2
      hc_vals(1,2,1,1)=3,4
       
      hc_vals(1,1,2,1)=5,6
      hc_vals(1,2,2,1)=7,8
       
      ! Time 1 values
      hc_vals(1,1,1,2)=11,21
      hc_vals(1,2,1,2)=31,41
       
      hc_vals(1,1,2,2)=51,61
      hc_vals(1,2,2,2)=71,81
       
      *dim,tb_vals,tab4,2,2,2,2,x,y,z,time
      *taxis,tb_vals(1),1,0,1
      *taxis,tb_vals(1),2,0,1
      *taxis,tb_vals(1),3,0,1
      *taxis,tb_vals(1),4,0,1
       
      ! Time 0 values
      tb_vals(1,1,1,1)=10,200
      tb_vals(1,2,1,1)=30,400
       
      tb_vals(1,1,2,1)=50,60
      tb_vals(1,2,2,1)=70,80
       
      ! Time 1 values
      tb_vals(1,1,1,2)=110,210
      tb_vals(1,2,1,2)=310,410
       
      tb_vals(1,1,2,2)=510,610
      tb_vals(1,2,2,2)=710,810
       
      nsel,s,ext
      sf,all,conv,%hc_vals%,%tb_vals%
      nsel,all
      • Francesco Miccoli
        Subscriber

        Why when defining table values like in:
        hc_vals(1,1,1,1)=1,2
        do we put two values after the =? Is that something that I should do with a 2d table too?

    • dlooman
      Ansys Employee

      My example is only a 2x2x2x2 table, so I can specify the whole column of (2) values after the equal sign.  You can specify up to 10 values after the equal sign.  

      • Francesco Miccoli
        Subscriber

        Thanks, well your code looks very similar to mine, I don't understand why it is not working then... maybe something to do with coordinates? If I say that the h values are a function of X, does the solver look at the X value of the name_selection with an absolute value (so the first element of named_selection is at X=0) or with a relative one?

    • Chandra Sekaran
      Ansys Employee

      The X value is interpreted to be in the coordinate system that you choose. The default is Global Cartesian system. So the solver will look at the X coordinate of every point in your named selection and interpolate to get the corresponding h value at that location.

       

      • Francesco Miccoli
        Subscriber

        Then why does the result of the simulation is indipendent on the values of X that I use? For example, this code:

        *dim,bartz,TABLE,4,3,X,TEMP
        *taxis,bartz(1),1,0.13,0.15,0.16,0.20
        *taxis,bartz(1),2,200,800,1400
        bartz(1,1) = 1000
        bartz(2,1) = 10000
        bartz(3,1) = 10000
        bartz(4,1) = 1000

        bartz(1,2) = 1000
        bartz(2,2) = 10000
        bartz(3,2) = 10000
        bartz(4,2) = 1000

        bartz(1,3) = 1000
        bartz(2,3) = 10000
        bartz(3,3) = 10000
        bartz(4,3) = 1000

        *dim,bulk,TABLE,4,X
        *taxis,bulk(1),1,0.13,0.15,0.16,0.20
        bulk(1) = 500
        bulk(2) = 3500
        bulk(3) = 3500
        bulk(4) = 500

        sf,nozzle_selection,conv,%bartz%,%bulk%

        produces the same exact results as this? (I am changing the X coordinate)

        *dim,bartz,TABLE,4,3,X,TEMP
        *taxis,bartz(1),1,0,0.02,0.03,0.05
        *taxis,bartz(1),2,200,800,1400
        bartz(1,1) = 1000
        bartz(2,1) = 10000
        bartz(3,1) = 10000
        bartz(4,1) = 1000

        bartz(1,2) = 1000
        bartz(2,2) = 10000
        bartz(3,2) = 10000
        bartz(4,2) = 1000

        bartz(1,3) = 1000
        bartz(2,3) = 10000
        bartz(3,3) = 10000
        bartz(4,3) = 1000

        *dim,bulk,TABLE,4,X
        *taxis,bulk(1),1,0,0.02,0.03,0.05
        bulk(1) = 500
        bulk(2) = 3500
        bulk(3) = 3500
        bulk(4) = 500

        sf,nozzle_selection,conv,%bartz%,%bulk%

        It seems like it is not understanding that X is the coordinate, otherwise why would the result be indipendet of the X value?

    • Francesco Miccoli
      Subscriber

      Also, I am setting the bulk temperature variable with X with a max value of 2500K. But then, whith no other heat generation or transfer, the surface temperature of the piece subject to the convection gets to 2700K, making it evident that there is an error somewhere

    • Chandra Sekaran
      Ansys Employee

      Hello Francesco, can you go to Post1 (example commands below) and see if the loads are being applied properly?

      /post1

      set,last   ! last time point

      cmsel,s,nozzle_selection    ! select the nodes of the nozzle

      nlist             ! list and make sure the X coordinates are in the range of 0.13 to 0.20

      sflist         ! based on time and X you should be see if the right values are being applied from the table.

      Right now I am not sure whether you are saying the load is not being applied correctly or if you are saying the load is being applied correctly but the results are wrong.

      • Francesco Miccoli
        Subscriber

        Thank you for the help with commands, it happears as if the film coefficient and bulk temperatures are not interpolated (note that I have used the APDL commands I sent in the reply before, but started the X vector from 0.13 instead of 0):

        ***** MAPDL RESULTS INTERPRETATION (POST1) *****

         *** NOTE ***                            CP =      26.344   TIME= 21:23:59
         Reading results into the database (SET command) will update the current 
         displacement and force boundary conditions in the database with the     
         values from the results file for that load set.  Note that any          
         subsequent solutions will use these values unless action is taken to    
         either SAVE the current values or not overwrite them (/EXIT,NOSAVE).    


         USE LAST SUBSTEP ON RESULT FILE  FOR LOAD CASE 0 

         SET COMMAND GOT LOAD STEP=     6  SUBSTEP=    51  CUMULATIVE ITERATION=   449
           TIME/FREQUENCY=  6.0000    
         TITLE= mk1--Transient Thermal (L5)                                             

         SELECT      COMPONENT NOZZLE_SELECTION                                                                                                                                                                                                                                                

         LIST ALL SELECTED NODES.   DSYS=      0

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     26.594

         mk1--Transient Thermal (L5)                                                   

         

            NODE        X             Y             Z           THXY     THYZ     THZX
                1  0.18635       0.27697E-001   0.0000          0.00     0.00     0.00
                2  0.13040       0.28297E-001   0.0000          0.00     0.00     0.00
                3  0.18540       0.27418E-001 -0.60031E-017     0.00     0.00     0.00
                4  0.18444       0.27129E-001 -0.57611E-017     0.00     0.00     0.00
                .... (omitted)
               50  0.14257       0.16494E-001  0.45903E-017     0.00     0.00     0.00

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     27.531

         mk1--Transient Thermal (L5)                                                   

         

            NODE        X             Y             Z           THXY     THYZ     THZX
               51  0.14178       0.17095E-001  0.46890E-017     0.00     0.00     0.00
               .... (omitted)
             1735  0.15704       0.14044E-001  0.17629E-017     0.00     0.00     0.00

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     28.703

         mk1--Transient Thermal (L5)                                                   

         

            NODE        X             Y             Z           THXY     THYZ     THZX
             1737  0.15620       0.13509E-001  0.20108E-017     0.00     0.00     0.00
             .... (omitted)
             1797  0.13145       0.27243E-001  0.56777E-017     0.00     0.00     0.00

         *** NOTE ***                            CP =      29.406   TIME= 21:23:59
         The surface loads listed are the current database values and are not    
         necessarily the values corresponding to the current results data set.   
         Tabular boundary conditions, however, do list values corresponding to   
         the current results set.                                                

         LIST NODAL SURFACE LOAD CONV FOR ALL SELECTED NODES

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     29.406

         mk1--Transient Thermal (L5)                                                   

         


         ELEMENT  LKEY     FACE NODES       FILM COEFFICIENT      TBULK
             350     2           1            1000.00000      500.000000    
                                 3            1000.00000      500.000000    
             351     2           3            1000.00000      500.000000    
                                 4            1000.00000      500.000000    
             352     2           4            1000.00000      500.000000    
                                 5            1000.00000      500.000000    
             353     2           5            1000.00000      500.000000    
                                 6            1000.00000      500.000000    
             354     2           6            1000.00000      500.000000    
                                 7            1000.00000      500.000000    
             355     2           7            1000.00000      500.000000    
                                 8            1000.00000      500.000000    
             356     2           8            1000.00000      500.000000    
                                 9            1000.00000      500.000000    
             357     2           9            1000.00000      500.000000    
                                10            1000.00000      500.000000    
             358     2          10            1000.00000      500.000000    
                                11            1000.00000      500.000000    
             359     2          11            1000.00000      500.000000    
                                12            1000.00000      500.000000    
             360     2          12            1000.00000      500.000000    
                                13            1000.00000      500.000000    
             361     2          13            1000.00000      500.000000    
                                14            1000.00000      500.000000    
             362     2          14            1000.00000      500.000000    
                                15            1000.00000      500.000000    
             363     2          15            1000.00000      500.000000    
                                16            1000.00000      500.000000    
             364     2          16            1000.00000      500.000000    
                                17            1000.00000      500.000000    
             365     2          17            1000.00000      500.000000    
                                18            1000.00000      500.000000    
             366     2          18            1000.00000      500.000000    
                                19            1000.00000      500.000000    
             367     2          19            1000.00000      500.000000    
                                20            1000.00000      500.000000    
             368     2          20            1000.00000      500.000000    
                                21            1000.00000      500.000000    
             369     2          21            1000.00000      500.000000    
                                22            1000.00000      500.000000    
             370     2          22            1000.00000      500.000000    
                                23            1000.00000      500.000000    
             371     2          23            1000.00000      500.000000    
                                24            1000.00000      500.000000    
             372     2          24            1000.00000      500.000000    
                                25            1000.00000      500.000000    
             373     2          25            1000.00000      500.000000    
                                26            1000.00000      500.000000    
             374     2          26            1000.00000      500.000000    
                                27            1000.00000      500.000000    

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     29.406

         mk1--Transient Thermal (L5)                                                   

         


         ELEMENT  LKEY     FACE NODES       FILM COEFFICIENT      TBULK
             375     2          27            1000.00000      500.000000    
                                28            1000.00000      500.000000    
             376     2          28            1000.00000      500.000000    
                                29            1000.00000      500.000000    
             377     2          29            1000.00000      500.000000    
                                30            1000.00000      500.000000    
             378     2          30            1000.00000      500.000000    
                                31            1000.00000      500.000000    
             379     2          31            1000.00000      500.000000    
                                32            1000.00000      500.000000    
             380     2          32            1000.00000      500.000000    
                                33            1000.00000      500.000000    
             381     2          33            1000.00000      500.000000    
                                34            1000.00000      500.000000    
             382     2          34            1000.00000      500.000000    
                                35            1000.00000      500.000000    
             383     2          35            1000.00000      500.000000    
                                36            1000.00000      500.000000    
             384     2          36            1000.00000      500.000000    
                                37            1000.00000      500.000000    
             385     2          37            1000.00000      500.000000    
                                38            1000.00000      500.000000    
             386     2          38            1000.00000      500.000000    
                                39            1000.00000      500.000000    
             387     2          39            1000.00000      500.000000    
                                40            1000.00000      500.000000    
             388     2          40            1000.00000      500.000000    
                                41            1000.00000      500.000000    
             389     2          41            1000.00000      500.000000    
                                42            1000.00000      500.000000    
             390     2          42            1000.00000      500.000000    
                                43            1000.00000      500.000000    
             391     2          43            1000.00000      500.000000    
                                44            1000.00000      500.000000    
             392     2          44            1000.00000      500.000000    
                                45            1000.00000      500.000000    
             393     2          45            1000.00000      500.000000    
                                46            1000.00000      500.000000    
             394     2          46            1000.00000      500.000000    
                                47            1000.00000      500.000000    
             395     2          47            1000.00000      500.000000    
                                48            1000.00000      500.000000    
             396     2          48            1000.00000      500.000000    
                                49            1000.00000      500.000000    
             397     2          49            1000.00000      500.000000    
                                50            1000.00000      500.000000    
             398     2          50            1000.00000      500.000000    
                                51            1000.00000      500.000000    
             399     2          51            1000.00000      500.000000    
                                52            1000.00000      500.000000    

         *** MAPDL - ENGINEERING ANALYSIS SYSTEM  RELEASE 2023 R2          23.2     ***
         Ansys Mechanical Enterprise Academic Research     
         01148981  VERSION=WINDOWS x64   21:23:59  MAR 11, 2024 CP=     29.641

         mk1--Transient Thermal (L5)                                                   

         


         ELEMENT  LKEY     FACE NODES       FILM COEFFICIENT      TBULK
             400     2          52            1000.00000      500.000000    
                                53            1000.00000      500.000000    
             401     2          53            1000.00000      500.000000    
                                54            1000.00000      500.000000    
             402     2          54            1000.00000      500.000000    
                                55            1000.00000      500.000000    
             403     2          55            1000.00000      500.000000    
                                56            1000.00000      500.000000    
             404     2          56            1000.00000      500.000000    
                                57            1000.00000      500.000000    
             405     2          57            1000.00000      500.000000    
                                58            1000.00000      500.000000    
             406     2          58            1000.00000      500.000000    
                                59            1000.00000      500.000000    
             407     2          59            1000.00000      500.000000    
                                60            1000.00000      500.000000    
             408     2          60            1000.00000      500.000000    
                                61            1000.00000      500.000000    
             409     2          61            1000.00000      500.000000    
                                62            1000.00000      500.000000    
             410     2          62            1000.00000      500.000000    
                                63            1000.00000      500.000000    
             411     2          63            1000.00000      500.000000    
                                64            1000.00000      500.000000    
             412     2          64            1000.00000      500.000000    
                                65            1000.00000      500.000000    
             413     2          65            1000.00000      500.000000    
                                66            1000.00000      500.000000    
             414     3          66            1000.00000      500.000000    
                                 2            1000.00000      500.000000    

         Set Encoding of XML File to:ISO-8859-1

         Set Output of XML File to:
             PARM,     ,     ,     ,     ,     ,     ,     ,     ,     ,     ,     ,
                 ,     ,     ,     ,     ,     ,     ,

         DATABASE WRITTEN ON FILE  parm.xml                                                                                                                                                                                                                                                            

         EXIT THE MAPDL POST1 DATABASE PROCESSOR

         

    • Chandra Sekaran
      Ansys Employee

      Hi Francesco,

      I think the *dim command below is not right. 

      *dim,bartz,TABLE,4,3,X,TEMP

      It should be

      *dim,bartz,table,4,3,1,x,temp  ! Must give the K dimension. You can leave it as blank (default to 1).

      Similarly the other array should be 

      *dim,bulk,TABLE,50,,,X

       

      *DIM, Par, Type, IMAX, JMAX, KMAX, Var1, Var2, Var3, CSYSID

      • Francesco Miccoli
        Subscriber

        I can now see that something has changed, using:

        *dim,bartz,TABLE,50,61,1,X,TEMP
        *taxis,bartz(1),1,0.13,0.130976,0.131951,0.132927,0.133902,0.134878,...,0.185
        *taxis,bartz(1),2,0,50,100,150,200,250,300,350,400,450,...,3000

        and 

        *dim,bulk,TABLE,50,1,1,X
        *taxis,bulk(1),1,0.13,0.130976,0.131951,0.132927,0.133902,0.134878,...,0.185

        I get the following result

        ELEMENT LKEY FACE NODES FILM COEFFICIENT TBULK
        350 2 1 8217.95590 2663.39620
        3 8217.95590 2663.39620
        351 2 3 8217.95590 2663.39620
        4 8217.95590 2663.39620
        352 2 4 8217.95590 2663.39620
        5 8217.95590 2663.39620
        353 2 5 8217.95590 2663.39620
        6 8217.95590 2663.39620
        354 2 6 8217.95590 2663.39620
        7 8217.95590 2663.39620
        355 2 7 8217.95590 2663.39620
        8 8217.95590 2663.39620
        356 2 8 8217.95590 2663.39620
        9 8217.95590 2663.39620
        357 2 9 8217.95590 2663.39620
        10 8217.95590 2663.39620
        358 2 10 8217.95590 2663.39620
        11 8217.95590 2663.39620
        359 2 11 8217.95590 2663.39620
        12 8217.95590 2663.39620
        360 2 12 8217.95590 2663.39620
        13 8217.95590 2663.39620
        361 2 13 8217.95590 2663.39620
        14 8217.95590 2663.39620
        362 2 14 8217.95590 2663.39620
        15 8217.95590 2663.39620
        363 2 15 8217.95590 2663.39620
        16 8217.95590 2663.39620
        364 2 16 8217.95590 2663.39620
        17 8217.95590 2663.39620
        365 2 17 8217.95590 2663.39620
        18 8217.95590 2663.39620
        366 2 18 8217.95590 2663.39620
        19 8217.95590 2663.39620
        367 2 19 8217.95590 2663.39620
        20 8217.95590 2663.39620
        368 2 20 8217.95590 2663.39620
        21 8217.95590 2663.39620
        369 2 21 8217.95590 2663.39620
        22 8217.95590 2663.39620
        370 2 22 8217.95590 2663.39620
        23 8217.95590 2663.39620
        371 2 23 8217.95590 2663.39620
        24 8217.95590 2663.39620
        372 2 24 8217.95590 2663.39620
        25 8217.95590 2663.39620
        373 2 25 8217.95590 2663.39620
        26 8217.95590 2663.39620
        374 2 26 8217.95590 2663.39620
        27 8217.95590 2663.39620

        *** MAPDL - ENGINEERING ANALYSIS SYSTEM RELEASE 2023 R2 23.2 ***
        Ansys Mechanical Enterprise Academic Research
        01148981 VERSION=WINDOWS x64 09:14:44 MAR 12, 2024 CP= 60.531

        mk1--Transient Thermal (L5)




        ELEMENT LKEY FACE NODES FILM COEFFICIENT TBULK
        375 2 27 8217.95590 2663.39620
        28 8217.95590 2663.39620
        376 2 28 8217.95590 2663.39620
        29 8217.95590 2663.39620
        377 2 29 8217.95590 2663.39620
        30 8217.95590 2663.39620
        378 2 30 8217.95590 2663.39620
        31 8217.95590 2663.39620
        379 2 31 8217.95590 2663.39620
        32 8217.95590 2663.39620
        380 2 32 8217.95590 2663.39620
        33 8217.95590 2663.39620
        381 2 33 8217.95590 2663.39620
        34 8217.95590 2663.39620
        382 2 34 8217.95590 2663.39620
        35 8217.95590 2663.39620
        383 2 35 8217.95590 2663.39620
        36 8217.95590 2663.39620
        384 2 36 8217.95590 2663.39620
        37 8217.95590 2663.39620
        385 2 37 8217.95590 2663.39620
        38 8217.95590 2663.39620
        386 2 38 8217.95590 2663.39620
        39 8217.95590 2663.39620
        387 2 39 8217.95590 2663.39620
        40 8217.95590 2663.39620
        388 2 40 8217.95590 2663.39620
        41 8217.95590 2663.39620
        389 2 41 8217.95590 2663.39620
        42 8217.95590 2663.39620
        390 2 42 8217.95590 2663.39620
        43 8217.95590 2663.39620
        391 2 43 8217.95590 2663.39620
        44 8217.95590 2663.39620
        392 2 44 8217.95590 2663.39620
        45 8217.95590 2663.39620
        393 2 45 8217.95590 2663.39620
        46 8217.95590 2663.39620
        394 2 46 8217.95590 2663.39620
        47 8217.95590 2663.39620
        395 2 47 8217.95590 2663.39620
        48 8217.95590 2663.39620
        396 2 48 8217.95590 2663.39620
        49 8217.95590 2663.39620
        397 2 49 8217.95590 2663.39620
        50 8217.95590 2663.39620
        398 2 50 8217.95590 2663.39620
        51 8217.95590 2663.39620
        399 2 51 8217.95590 2663.39620
        52 8217.95590 2663.39620

        *** MAPDL - ENGINEERING ANALYSIS SYSTEM RELEASE 2023 R2 23.2 ***
        Ansys Mechanical Enterprise Academic Research
        01148981 VERSION=WINDOWS x64 09:14:44 MAR 12, 2024 CP= 61.000

        mk1--Transient Thermal (L5)




        ELEMENT LKEY FACE NODES FILM COEFFICIENT TBULK
        400 2 52 8217.95590 2663.39620
        53 8217.95590 2663.39620
        401 2 53 8217.95590 2663.39620
        54 8217.95590 2663.39620
        402 2 54 8217.95590 2663.39620
        55 8217.95590 2663.39620
        403 2 55 8217.95590 2663.39620
        56 7781.48389 2666.04635
        404 2 56 7781.48389 2666.04635
        57 7313.97781 2668.72042
        405 2 57 7313.97781 2668.72042
        58 6883.48184 2670.97915
        406 2 58 6883.48184 2670.97915
        59 6498.70836 2672.78417
        407 2 59 6498.70836 2672.78417
        60 6146.30347 2674.31048
        408 2 60 6146.30347 2674.31048
        61 5818.84277 2675.63454
        409 2 61 5818.84277 2675.63454
        62 5515.72008 2676.77244
        410 2 62 5515.72008 2676.77244
        63 5243.28918 2677.69982
        411 2 63 5243.28918 2677.69982
        64 4988.25853 2678.52000
        412 2 64 4988.25853 2678.52000
        65 4749.60914 2679.24255
        413 2 65 4749.60914 2679.24255
        66 4529.84968 2679.85958
        414 3 66 4529.84968 2679.85958
        2 4328.79584 2680.38574

        Still there are some nodes that are not correctly interpolated, but I can't figure out why some are and some are not!

      • Francesco Miccoli
        Subscriber

        Do you have any idea why it could be interpolating on some nodes only?

    • dlooman
      Ansys Employee

      Hard to say.  Is it the film coefficient or tbulk that isn't interpolated?  Did you check your table input in the APLD gui?

      • Francesco Miccoli
        Subscriber

        Both are not interpolated for most nodes, for some nodes (see previous comment) they are though, even if ALL the nodes are in the X and TEMP range of the table...
        Regarding the APDL gui I am having issues importing the data (if not element by element). The values of the table though are generated on matlab and their plot is correct.

    • dlooman
      Ansys Employee

      The APDL gui would tell you that you APDL input is correct.  All you need to do is cut and paste the commands that create the tables into the input window.  You don't need to have any model active.

      • Francesco Miccoli
        Subscriber

        I did that, pasted the whole command and got only this:

        so I guess the commands are right, but I still have the issue that some nodes are interpolated and some not

    • dlooman
      Ansys Employee

      I didn't want you to include any of the other commands in the cut and paste.  Just the table definition.  After cutting and pasting them in you need to pick on Parameters in the top tool bar and then Array Parameters > from the drop down menu.  Then Define/Edit.  You should see you array name in a list that you can pick on.

      • Francesco Miccoli
        Subscriber

        This is it. I don't understand why there are values e-31...

    • dlooman
      Ansys Employee

      That means there is something wrong with your *taxis commands.

      • Francesco Miccoli
        Subscriber

        from the commands "guide" : 
        *TAXIS, ParmLoc, nAxis, Val1, Val2, Val3, Val4, Val5, Val6, Val7, Val8, Val9, Val10

        for my command I used: 

        *dim,bartz,TABLE,50,61,1,X,TEMP

        *taxis,bartz(1),1,0.107,0.108088,0.109176,...

        *taxis,bartz(1),2,0,50,100,150,200,...

        the only place I could see an issue is the bartz(1) part, but I wouldn't know how to correct it

    • dlooman
      Ansys Employee

      You can only input 10 values at a time.  How did you enter all 50 or 61 values?

Viewing 13 reply threads
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