XANSYS Message #: 38495

XANSYS Message: 38495 [Go back to message list]
[bookmark on del.icio.us]
No rating yet

Subject: Creep, Primary+Secondary
Author: Ian Stewart rabet@
Date: 2002-06-04 18:05:00

Hi, I am doing a creep analysis but I have faced a big problem! First, I have chosen Explicit Creep(told to do it this way). I have to do the creep analysis for the primary creep + secondary creep. In other words, my model, obeys a primary creep equation for the "Primary Creep Region", and following that, obeys a secondary creep equation for the "Secondary Creep Region". From my previous posts for help, I had found that I can apply both Primary and Secondary equations at once. I have entered Primary Creep Eq. with C6=1 and Secondary Creep Eq. with C12=1 this way: In /prep7: tb,creep,1 tbdata, 1, 1/2*6.83e-54, 6.2, -1/2, , , 1 tbdata,7, 9.9e-56, 6.2, 0, 0, 0, 1 Would you please tell me what's wrong with this definition? The results which I obtain with the above Creep Defenition (for the desired primary +secondary effect),are the same results which I get from JUST the Primary Creep! In other words, it seems to me that the second equation has no effect! Also, I have been told that if one specifies more than one type of creep (like in this case) ANSYS calculates the "Combined Effects". What if I have to do it this way: apply Primary Creep Eq from time=0 to time=steady state. Then, apply Secondary creep Eq from time=onset of the steady state up to time=onset of tertiary creep. I have to obtain when my model enters to the Tertiary Creep Region (for life estimation), but how? The Tertiary Creep is not important. But I have to know when it begins. Please help me. Ian Stewart Rabet research POBOX: 51390 Dubai, UAE Tel:+971-4-2226338 Fax:+971-4-2218898

Posts possibly associated with message #38495		Author	Date	Score
`38495`	`Creep, Primary+Secondary`	`Ian Stewart rabet@`	`2002/06/04`
`38527`	`Creep, Primary+Secondary`	`Ian Stewart rabet@`	`2002/06/05`
`38528`	`Re: Creep, Primary+Secondary`	`Fernand Thomassy`	`2002/06/05`	`-10`
`38530`	`Re: Creep, Primary+Secondary`	`Rick Fischer`	`2002/06/05`