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Tracking displacement on a thermal actuator after remove voltage source

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Hello,

I am new in comsol. Now, I am trying to simulate displacement of a thermal actuator under 5V. I am using the time-dependent modal. I can get results of stress, displacement, and temperature. However, I would like to konw how to study the displacement after I removed the 5V volatge source. For example, I want to apply 5V for 1s then turn it off. For a time-dependent study, I would like to know what will happen within 2s (0-1s, 5V; 1-2s, 0V). How to set this condition in comsol. My comsol model is attached.

Thanks,

Charlie



3 Replies Last Post Aug 20, 2018, 3:10 a.m. EDT

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Posted: 6 years ago Aug 17, 2018, 5:25 a.m. EDT

Hi,

I think you need to consider t variable which means time.

And, to consider the continuous electric potential, I think it is better to use Step function in Definitions > Functions.

I attached a sample model.

Thanks.

Hi, I think you need to consider **t** variable which means time. And, to consider the continuous electric potential, I think it is better to use Step function in Definitions > Functions. I attached a sample model. Thanks.


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Posted: 6 years ago Aug 17, 2018, 10:05 a.m. EDT

Hello Kim,

Thank you for your answer. I appricate your help. Now, I define a piecewise funtion to apply a time dependent voltage. However, when I set the electrical potential is pw1 (whichi is the piecewise function), I can not get the result since 'failed to evaluate variabe'. The time dependent study is set as range (0,0.2,2) unit is s. Please see the images in the attachment. How can I apply this piecewise function as a input voltage?

Best, Charlie

Hello Kim, Thank you for your answer. I appricate your help. Now, I define a piecewise funtion to apply a time dependent voltage. However, when I set the electrical potential is pw1 (whichi is the piecewise function), I can not get the result since 'failed to evaluate variabe'. The time dependent study is set as range (0,0.2,2) unit is s. Please see the images in the attachment. How can I apply this piecewise function as a input voltage? Best, Charlie


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Posted: 6 years ago Aug 20, 2018, 3:10 a.m. EDT

Hi,

How about use pw1(t[1/s])?

Thanks.

Kim

Hi, How about use pw1(t[1/s])? Thanks. Kim

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