Species Transport model

sbkashif · August 19, 2015, 09:33

As stated in the literature, in species transport model mixture formulation where components are mixed at molecular level and velocity and temperature are the same for all components.

Given the case for non-reactive mixture and the simulations I carried out, the mass fraction data is available for different components at various axial locations inside a cylinderical channel.

However, I intend to know how the species transport model can be used to know the extent of mixing.

Secondly, since there is no reaction, what is the factor that is causing the mass fraction change.

Karu_p · September 4, 2015, 08:24

Hello sbkashif,

Did u able to solve the problem. If so, please help me. I am also facing the same problem.

sbkashif · September 4, 2015, 10:48

Not exactly sure whether the approach is right but will share my thoughts.

The species model gives the mass fraction data. Say Species A has m.f. x and Species B has mf. y at the inlet.

The mass fraction data is reported at all locations till the outlet.

This data can be used to analyse the extent of mixing. If both the species has a mass fraction of 0.5 each, this is the ideal case.

Karu_p · September 4, 2015, 11:04

Thanks for the early reply.

I will make myself clear. I want to simulate a T micro-mixer with two different liquids entering at the two opposite ends and get mixed in the micro channel by diffusion. Do u have any idea how it is done.

For now, I am using only species transport model but I cannot not visualize if mixing taking place or not.

Please do reply. I really need it.

sbkashif · September 4, 2015, 11:21

Are you getting mass fractions?

As I said, the mass fraction of both the species as 0.5 at a location would signify ideal mixing at that location. The extent of variation from that fraction can be accounted for lesser mixing.

Pathlines may also give an idea.

Given your problem, I think you would also have to use multiphase model as well.

August 19, 2015, 09:33	Species Transport model	#1
sbkashif New Member Join Date: Jul 2015 Posts: 10 Rep Power: 11	As stated in the literature, in species transport model mixture formulation where components are mixed at molecular level and velocity and temperature are the same for all components. Given the case for non-reactive mixture and the simulations I carried out, the mass fraction data is available for different components at various axial locations inside a cylinderical channel. However, I intend to know how the species transport model can be used to know the extent of mixing. Secondly, since there is no reaction, what is the factor that is causing the mass fraction change.

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September 4, 2015, 08:24		#2
Karu_p New Member Join Date: Aug 2015 Posts: 5 Rep Power: 11	Hello sbkashif, Did u able to solve the problem. If so, please help me. I am also facing the same problem.

September 4, 2015, 10:48		#3
sbkashif New Member Join Date: Jul 2015 Posts: 10 Rep Power: 11	Not exactly sure whether the approach is right but will share my thoughts. The species model gives the mass fraction data. Say Species A has m.f. x and Species B has mf. y at the inlet. The mass fraction data is reported at all locations till the outlet. This data can be used to analyse the extent of mixing. If both the species has a mass fraction of 0.5 each, this is the ideal case.

September 4, 2015, 11:04		#4
Karu_p New Member Join Date: Aug 2015 Posts: 5 Rep Power: 11	Thanks for the early reply. I will make myself clear. I want to simulate a T micro-mixer with two different liquids entering at the two opposite ends and get mixed in the micro channel by diffusion. Do u have any idea how it is done. For now, I am using only species transport model but I cannot not visualize if mixing taking place or not. Please do reply. I really need it.

September 4, 2015, 11:21		#5
sbkashif New Member Join Date: Jul 2015 Posts: 10 Rep Power: 11	Are you getting mass fractions? As I said, the mass fraction of both the species as 0.5 at a location would signify ideal mixing at that location. The extent of variation from that fraction can be accounted for lesser mixing. Pathlines may also give an idea. Given your problem, I think you would also have to use multiphase model as well.