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How to define perturbation in initial conditions?

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Hi, I'm remodeling a paper, and I need to define a perturbation in my initial conditions to validate my model with the results in paper. Paper has calculated the stationary form of the equation and then added a 1% perturbation in the sationary results and put the result in the initial condition for the time dependent model, I need to know how I can do this? Exact sentence of the paper: "The initial condition for the transient calculations is generated by applying a locally 1% random perturbation to the anion and cation concentration fields obtained from the steady calculation."


3 Replies Last Post 2018/03/29 8:44 GMT-4

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Posted: 6 years ago 2017/12/09 14:04 GMT-5

Dear Harry,

I recommend you to create two studies for the same model. The first will be the stationary one, and the second will be time-dependent with the initial conditions from the first. Simply define ICs in the second study by using 'withsol' operator and add the perturbation to it.

Dear Harry, I recommend you to create two studies for the same model. The first will be the stationary one, and the second will be time-dependent with the initial conditions from the first. Simply define ICs in the second study by using 'withsol' operator and add the perturbation to it.

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Posted: 6 years ago 2018/03/07 9:39 GMT-5

Hi, I have the same problem. How to I add the perturbation? The initial condition allows me to choose only from one of the solutions. Thank you

Hi, I have the same problem. How to I add the perturbation? The initial condition allows me to choose only from one of the solutions. Thank you

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Posted: 6 years ago 2018/03/29 8:44 GMT-4

Dear Harry,

I recommend you to create two studies for the same model. The first will be the stationary one, and the second will be time-dependent with the initial conditions from the first. Simply define ICs in the second study by using 'withsol' operator and add the perturbation to it.

Hello Dear Vasily I don't know how to use the so called 'withsol' operator, would you please give me an example? or any instruction on how to use it in IC?

>Dear Harry, > >I recommend you to create two studies for the same model. The first will be the stationary one, and the second will be time-dependent with the initial conditions from the first. Simply define ICs in the second study by using 'withsol' operator and add the perturbation to it. Hello Dear Vasily I don't know how to use the so called 'withsol' operator, would you please give me an example? or any instruction on how to use it in IC?

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