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Dielectrophoresis

Posted 12 mar 2013, 04:08 GMT-4 Low-Frequency Electromagnetics, Charged Particle Tracing, Fluid & Heat, Microfluidics, Particle Tracing for Fluid Flow Version 4.4 3 Replies

Kah Khim Khoo
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Hi there. I tried to observe the particle movement effect through the "particle tracing for fluid module". However, the result of particle trajectories didn't show up any particle movement. Please help. Thanks
3 Replies Last Post 29 set 2014, 04:45 GMT-4
Navid Engineer
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Posted: 1 decade ago 3 apr 2013, 10:40 GMT-4
Hi,

maybe time steps are too large.

Try with small time steps

Navid
Hi, maybe time steps are too large. Try with small time steps Navid
Chang-Ho Han
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Posted: 1 decade ago 14 lug 2013, 04:23 GMT-4
Hi,
I'm also simulating similar case with yours^^

First I used 'Laminar Flow module' with stationary solver (GMRES),
As there are non-symmetric matrices in convective term of N-S equation, GMRES is effective.
Then I added two modules, 'Electrostatics' and 'Electric Current' module.
As Vdc+Vac = V1+V2cos(wt+phi) like this, Electrostatics module for DC, and Electric Current for AC.
And solve both moduleswith frequency domain solver (BiCGStab)
Because of AC, complex expressions are contained, so this solver will be useful.
Although some warning message will be appeared when solving Electrostatics module with frequency domain, there will be no problem.
Then, add 'Particle Tracing for Fluid Flow' module, and add two 'Dielectrophoretic force' setting.
One for DC (electric field(es/ccn)), and the other for AC (electric field(ec/ccn)).
And solve particle trajectories or time-dependent solver.
You can couple models successfully.

Note that it's some method by my personal experience, so if you have better idea, you don't need to follow these steps.

Good luck to your work^^
CH2
Hi, I'm also simulating similar case with yours^^ First I used 'Laminar Flow module' with stationary solver (GMRES), As there are non-symmetric matrices in convective term of N-S equation, GMRES is effective. Then I added two modules, 'Electrostatics' and 'Electric Current' module. As Vdc+Vac = V1+V2cos(wt+phi) like this, Electrostatics module for DC, and Electric Current for AC. And solve both moduleswith frequency domain solver (BiCGStab) Because of AC, complex expressions are contained, so this solver will be useful. Although some warning message will be appeared when solving Electrostatics module with frequency domain, there will be no problem. Then, add 'Particle Tracing for Fluid Flow' module, and add two 'Dielectrophoretic force' setting. One for DC (electric field(es/ccn)), and the other for AC (electric field(ec/ccn)). And solve particle trajectories or time-dependent solver. You can couple models successfully. Note that it's some method by my personal experience, so if you have better idea, you don't need to follow these steps. Good luck to your work^^ CH2
shom
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Posted: 1 decade ago 29 set 2014, 04:45 GMT-4
I have a question regarding the solver while solving the dielectrophoresis:

I have amodel with microchannel witha fluid (water) and four electrodes for focusing the particle in the channel (i applied a 10Vpp AC field @ 2Hz), then i introduce the particle tracing with drag force and dielectrophoresis force.
so i consider a model ; where i have laminar flow, electric current and particle tracing(dielectrophoresis)
study steps:
study 1 : step 1--> stationary laminar flow
step 2--> time dependent flow (electric current)
study 2: step 1: time depenednt particle tracing
intial value dependent on study 1

also
study 1 : step 1--> stationary laminar flow

study 2: step 1--> time dependent flow (electric current)
step 2 --> time depenednt particle tracing
intial value dependent on study 1

also
Study 3: step1 --> stationary laminar flow
step 2 --> time dependent (electric current)
step 3--> time dependent particle tracing

I have no dielectrophoresis effect on the particle in the micro channel, they have the normal flow.



I have a question regarding the solver while solving the dielectrophoresis: I have amodel with microchannel witha fluid (water) and four electrodes for focusing the particle in the channel (i applied a 10Vpp AC field @ 2Hz), then i introduce the particle tracing with drag force and dielectrophoresis force. so i consider a model ; where i have laminar flow, electric current and particle tracing(dielectrophoresis) study steps: study 1 : step 1--> stationary laminar flow step 2--> time dependent flow (electric current) study 2: step 1: time depenednt particle tracing intial value dependent on study 1 also study 1 : step 1--> stationary laminar flow study 2: step 1--> time dependent flow (electric current) step 2 --> time depenednt particle tracing intial value dependent on study 1 also Study 3: step1 --> stationary laminar flow step 2 --> time dependent (electric current) step 3--> time dependent particle tracing I have no dielectrophoresis effect on the particle in the micro channel, they have the normal flow.

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