BINARY OUTPUT FILES

[rrakos]

Hello,

I was wondering if anyone has written code to read in/write out the binary s01 (and other) files?

(I understand the structure of the file and yes I know I can output as ascii, I can do it with ascii but it is inefficient and my code writing skills are woeful)

Reason for request : I will retire before PTC to sort out node numbering and lack of signed vm stress.

Thanks

[skunks]

Hello Roland,

1. vibration analysis => analytical (example attached)

2. static analysis => fatigue advisor

regards

paul

[rrakos]

Hello Paul,

1. In case of a simple modal simulation, I have for the first mode 100 Hz for example. For this mode, I have a stress distribution - for undamped case, as far as I know. But what does this stress distribution mean exactly? How can I it reproduce? If I complate a vibration analyisis with 100 Hz - for undamped case - then I dont get same stress distribution. What is the reason? How can I reproduce the stress distribution same to the first mode of modal analysis?

2. OK so I have a modal analysis; 100 Hz at the first mode. It is evident for me that this structure can not be used on this frequency. But if the frequency is 30 Hz for exmaple, how can I calculate the limit cycle number (until breakage)? The max stress on 30 Hz is 50 MPa (for example). Now have I to use the pdf (sent by you) and see the cycle number on 50 MPa?

Please help me.

Thanks a lot

Roland

[skunks]

Hello Roland,

do You have a fatigue advisor license?

regards

paul

[rrakos]

Hello Paul,

No, I dont have it.

Can I estimate the lifetime without it?

Thanks

Roland

[skunks]

Hello Roland,

i think: unfortunately, no.

regards

paul

[rrakos]

Hello Paul,

ok, I understand.

At the moment, I have a simple dynamic freq.analysis, the settings is default:

I have a monitor point which shows the stress value in the function of frequency:

It can be seen that tha max stress is at the eigen freqency (~49Hz). But what does it mean this diagram for me? You tell me that it is not enough to evaluate lifetime. But what is the information which is useful for me from this result/diagram?

Thanks

Roland

[skunks]

info

regards

paul

[rrakos]

Hello Paul,

ohh, thanks a lot! I should begin my full vibration history with this document, but I didnt find similar one on internet.

Thanks a lot again

Roland

[rrakos]

Hello Paul,

ok, I studied the pdf is was very useful for me, thanks again.

So, I have a result. A simple body where the excitation apmlitude 1G, the frequency is 100Hz. At 100Hz the maximal stress is 150MPa. It does not reach the yield stress so based on it OK but the time of this excitation is 24 hours. For simualation of endurance test, I sould have fatigue advisor. Am I right?

At the moment, I dont have it. If I have a simple S-N curve for this material (including the fatique strength) than can I estimate the lifetime roughly?

Thanks

Roland

[skunks]

yes (roughly),

example attached:

regards

paul