TABLED1 data entry

Altair Forum User

Please help me on TABLED1 entries. I am not able to understand how to assign values in this table (help is not clear). If I want to assign random values can I do it or not. Say in Element flux I want to enter values as 

 

for time = 0 sec value is 4.2

for time = 4 sec value is 0

for time = 4.5 sec value is 4.2

for time = 8 sec value is 0

for time = 8.5 sec value is 4.2. and so on to say 16 sec or 24 sec or more. 

 

Can I input these types of random values to TABLED1 Card or not. 

Altair Forum User

Hi,

From Help:

 

Discontinuities may be specified between any two points except the two starting points or two end points.  For example, in Figure 1 discontinuities are allowed only between points x2 through x7.  Also, if y is evaluated at a discontinuity, the average value of y is used.  In Figure 1, the value of y at x = x3 is y = (y3+y4)/2.

3.

At least one continuation entry must be specified.

 

Can you make changes to your table as per the above and check if you can get results you desired?

Altair Forum User

Thanks for the reply sir. I have to apply a heat flux as (Need to apply this practically as per the problem statement) 

 

at time = 0 sec, Heat Flux = 4.2e6 W/m2

at time = 4 sec, Heat Flux = 0 W/m2

at time = 45 sec, Heat Flux = 0 W/m2

 

1. What I have entered in TABLED1 is

 

x1 = 0, y1 = 1 (Linear)

x2 = 4, y2 = 0 (Linear)

x3 = 45, y3 = 0 (Linear)

 

After I entered these I didn't get the right results.

 

2. And when I give values as below still didn't get the correct results:

 

x1 = 0, y1 = 4.2e6

x2 = 4, y2 = 0

x3 =45, y3 = 0

 

Maybe there is something else wrong in my model but I first want to conform this whether this is correct or not the above two tables which I input.

Please give your inputs

Altair Forum User

Hi,

 

can you make the following changes and check if you are able to get results?

 

x1=0  y1=4.2e6

x2=2  y2=4.2e6

x3=4  y3=2

x4=20  y4=0

x5= 40  y5=0

x6=45  y6=0

Altair Forum User

I have tried the above values it didnt work out sir. The values of temperature are in 9.99e5 ranges. May be something is terribly wrong in my problem but I have used the same procedure as given in tutorial OS-1090. Please suggest me something. Working on brake disc transient thermal behaviour. Boundary condition are ambient at 22 degree. Covection through disc surface. And heat flux on both discs. I can share model with you if you want.

Altair Forum User

Hi Shanky,

 

can you share your model?

 

Please use the dropbox link in my signature to share the model.

Altair Forum User

I have sent you the model files Sir. From- ishan.aggarwal1987@gmail.com

Altair Forum User

Thank you for sharing the files.

 

I will investigate and get back to you ASAP /emoticons/default_smile.png' alt=':)' srcset='/emoticons/smile@2x.png 2x' width='20' height='20'>

Altair Forum User

Hi....

if i want to do pretension for 1st 0-20 sec and next 20-100 sec for modal analysis then how i should define the table and  load step?

 

Please help in this regards.

 

thank you 

Altair Forum User

Hi Prajwal,

 

Could you please let me know what is the objective of such setup?

 

Modal analysis is not time dependent. 

Altair Forum User

Hi Sir,

I was simply trying different scenario..

 

can we control pretension in model?(like time dependent)

 

if I add time in pretension, Is that the model become Nonlinear?

Thank you

Altair Forum User

Hi,

 

Please check this tutorial:

RD-T: 3510 Cantilever Beam with Bolt Pretensioner

durukanbdilek

hello admins

I use materialss have frequency-dependent properties

I would like to enter E, G, netar data as .txt

but got error

can you help me

 

Rahul Rajan_21763

https://community.altair.com/community?id=community_question&sys_id=99464c761b2bd0908017dc61ec4bcb76

 

durukanbdilek

Mr @RAHUL

I have encountered TABLED1 entering error

'  Discontinuities are not allowed at TABLEM1 endpoints.'

Rahul Rajan_21763

As the error clearly indicates there are discontinuities in the table.I presume you have two different load values at the same time/frequency which is not allowed.

Please check the time data and filter it out to a valid input. If x is identical, you get an error. 

durukanbdilek

I work on frequency domain and I have not data on time domain

when data on convert to any plot I cannot see any discontinuities

on the other hand, I have only material datas for frequency dependent materials which you know

Rahul Rajan_21763

Can you share the Tablem1 end points?

durukanbdilek

at 1000 Hz 232E5 for E (young Modulus)

at 1000 Hz 2386233 for G (Shear Modulus)

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