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something about EHD ( electro-hydro dynamics )

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EHD is electro-hydro dynamics,i wanna know:In the 2D model, how to associate the electrostatic field with the space charge field, and set the volume force of the fluid to come from the electric field and the space charge at the same time


4 Replies Last Post 25.05.2021, 04:09 GMT-4
Robert Koslover Certified Consultant

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Posted: 4 years ago 21.05.2021, 21:12 GMT-4
Updated: 4 years ago 25.05.2021, 08:35 GMT-4

Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.

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Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.

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Posted: 4 years ago 25.05.2021, 04:03 GMT-4

Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.

>Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.


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Posted: 4 years ago 25.05.2021, 04:06 GMT-4

Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.

As shown in picture 7c3c5, this is the simulation result of others. The flow field shown by the ion wind model he made is only between the corona electrode and the collector.

>>Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all. As shown in picture 7c3c5, this is the simulation result of others. The flow field shown by the ion wind model he made is only between the corona electrode and the collector.

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Posted: 4 years ago 25.05.2021, 04:09 GMT-4

Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all.

The following pictures 1 and 2 show the model I made. I found that after adding the volume force, the entire watershed will have a velocity field. I don't know how to make his effect.

>Sounds like you'll want to use/combine the basic electrostatics module (es) with one of the fluid module applications (either laminar flow or not, depending on your fluid & physics regime). The electrostatics model already has charge density in its formulation. And in many of the fluid models, you can specify a volume force density, you can use that to couple the physics between the two. For that, I presume the simplest way is that you would specify the x and y components of the force density by entering the x and y components of the electric field (es.Ex and es.Ey) times the charge density, locally. This is a multiphysics problem. If you want more suggestions, I recommend that you describe your problem to the forum in much more detail and explain what level of assistance you need. If you already have a preliminary model and need help with some specifics, you might want to post that model to the forum and identify where you need specific help. There are many, many questions one could ask, after all. The following pictures 1 and 2 show the model I made. I found that after adding the volume force, the entire watershed will have a velocity field. I don't know how to make his effect.

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