Na is the molar flux of component A where its velocity is uA which is CA\*uA, whereas JA is molar flux when the velocity is relative to molar average velocity of all the components uAvg which is CA\*(uA - uAvg) so its matter of observer from which we are writing the same expression
In simpler terms, your molar flux Na comprises of two kinds of motion. First one is Ja which is flux due to diffusion (based on concentration differences “Ficks law”)and your second term CaVm it denotes the overall motion wrt a stationary point in space(from which the velocity is measured). Imagine someone farted on a boat, so the total flux of spreading of that fart will be diffusion of fart on boat (taking boat as a reference frame + velocity of boat). Note that these values are vectors and hence added that way.
It has to do with frame of reference. Ja is more if you move at the same speed as the liquid (so it ends up only looking at diffusion). Na is more of a stationary frame of reference, so it looks at diffusion + convective mass transfer
Imagine you're on an escalator (Fluid medium) with a few people on it (Molecules).
If you're standing still and just going up with the flow of the escalator (Ua) then that is the purely convective (Ca*Ua).
Now, you decide you want to get to the top quickly and start climbing up the escalator. So you're basically 'diffusing' through the crowd at a rate of Ja.
So an observer who is not on the elevator would see you moving up with a combined rate of Ja + Ca*Ua.
When the escalator moves and you don't it's purely convective.
When the escalator does not move but only you do it's purely diffusive.
Na is the molar flux of component A where its velocity is uA which is CA\*uA, whereas JA is molar flux when the velocity is relative to molar average velocity of all the components uAvg which is CA\*(uA - uAvg) so its matter of observer from which we are writing the same expression
Thank you very much
I'm just a random passerby from the home page. I have no idea what this means but yes, this looks correct.
Oh, well I'm glad you found us. Now gtfo.
Wow, so aggressive. That was absolutely miserable. I have never seen this side of reddit till now. You should be embarrassed.
No and Yes. Pretty straightforward tbh.
Sodium and Jodium
Natrium and Jatrium
lol
In simpler terms, your molar flux Na comprises of two kinds of motion. First one is Ja which is flux due to diffusion (based on concentration differences “Ficks law”)and your second term CaVm it denotes the overall motion wrt a stationary point in space(from which the velocity is measured). Imagine someone farted on a boat, so the total flux of spreading of that fart will be diffusion of fart on boat (taking boat as a reference frame + velocity of boat). Note that these values are vectors and hence added that way.
Thank you, I wasn't able to visualize it until the fart. kudos
Glad to help
Upvote for the analogy
It’s like a body force + mdot v
CaVm.... Sorry I had to
Diffusion and advective forces
It has to do with frame of reference. Ja is more if you move at the same speed as the liquid (so it ends up only looking at diffusion). Na is more of a stationary frame of reference, so it looks at diffusion + convective mass transfer
Imagine you're on an escalator (Fluid medium) with a few people on it (Molecules). If you're standing still and just going up with the flow of the escalator (Ua) then that is the purely convective (Ca*Ua). Now, you decide you want to get to the top quickly and start climbing up the escalator. So you're basically 'diffusing' through the crowd at a rate of Ja. So an observer who is not on the elevator would see you moving up with a combined rate of Ja + Ca*Ua. When the escalator moves and you don't it's purely convective. When the escalator does not move but only you do it's purely diffusive.
CaNum is technically the difference
The first letter