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Frequency response analysis - settings

Hello, I am writing to ask how correctly set FRA analysis?
I've made an example with simple plate:
1.Modal analysis:
<?xml version="1.0" encoding="UTF-8"?>

2. FRA analysis:
- frequency function like that (just for example)

image.png.0f8e3b00a4e3658efbc8321a9d10d116.png

- base excitation - acceleration
image.png.ec7a5064b37f5dd08613eeb64c490c56.png

3. Result:
image.png.261c58457f002543c48f33be68a15843.png

Result isn't the same as in modal analysis as I supposed to. I expected peak values in 26Hz, 116Hz, 169Hz where resonace will occur.

Somewhere I made a mistake, can anyone help me?

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GirishM

Hi Mateusz,

Can you confirm if you are using 2019.2 version of SimSolid?

Mateusz L

Hi Girish,
yes, I am using 2019.2.0 version.

GirishM

Please try the latest 2019.2.1 release. We fixed a bug related to FRF.

AlessioMM

Hello, I have quite the same problem, using Base excitation (Simsolid latest release 2019.4.1).

Just considering a simple input (constant acceleration 1m/sec^2) I can't obtain the same results between FEM analysis and Simsolid. Simsolid seems to convert and use the input acceleration in the wrong way respect to traditional FEM.

Frequency-function.JPG.24fb1b50d43931444ea8fc5b5f7e5423.JPG Base-Excitation.JPG.6aa7cb9795e2b74f51a2658f67bab7f6.JPG

Does anyone have already check the right correlation between Simsolid and FEM results in frf acceleration vs freq analysis (Base excitation)?

Koushik Chandrashekhar_21806

Hi,

As shown in the picture below, did you link your dynamic analysis to the conducted modal analysis? and gave proper frequency span?

<?xml version="1.0" encoding="UTF-8"?>