- #1
niketas
- 5
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Hello all!
This is a great site, congratulations!
I think I need help for proceeding with my reaction engineering project.
Now the problem is this: I have a packed bed reactor whose dynamic modelling I am supposed to complete. At t = 0, there is still air in the reactor with no net flow (Initial condition). When t > 0, I let air flow into the reactor with some initial velocity, which will, at certain intervals, will be increased (Time-dependent boundary condition; will be fixed after a certain while though). The unreacting flow in the reactor will reach steady state. Then I will let the reactive mixture into the reactor. This second stage I have no problem dealing with, i.e., reactive flow.
I am concerned with the initial unreacting flow. Since my fluid dynamics background is not strong, I needed your consultance. When the forced flow meets the still air residing in the reactor, what kind of modelling can I use? Can it be classified as a Riemann problem that moves downstream the reactor until there happens to be a moving chunk fluid at the lower end (downstream)?
Any other modelling difficulties, singularities that can arise when the moving fluid "bounces" into the stationary fluid? Shocks, instabilities?
Normally when I work with reactive flow, I do not take into account gravitational forces, that is, whether the reactor is horizontal or vertical. I suppose gravity comes into play in the unreacting flow case.
I would be grateful upon your suggestion of what model I should use, numerical method that needs to employed and any kind of tips.
If this is not the forum the thread should have been started, please feel free to move it to the appropriate forum.
Thank you for taking your time.
Best regards...
Niketas Konstantinidis
National Technical University
School of Chemical Engineering
Athens, Greece
This is a great site, congratulations!
I think I need help for proceeding with my reaction engineering project.
Now the problem is this: I have a packed bed reactor whose dynamic modelling I am supposed to complete. At t = 0, there is still air in the reactor with no net flow (Initial condition). When t > 0, I let air flow into the reactor with some initial velocity, which will, at certain intervals, will be increased (Time-dependent boundary condition; will be fixed after a certain while though). The unreacting flow in the reactor will reach steady state. Then I will let the reactive mixture into the reactor. This second stage I have no problem dealing with, i.e., reactive flow.
I am concerned with the initial unreacting flow. Since my fluid dynamics background is not strong, I needed your consultance. When the forced flow meets the still air residing in the reactor, what kind of modelling can I use? Can it be classified as a Riemann problem that moves downstream the reactor until there happens to be a moving chunk fluid at the lower end (downstream)?
Any other modelling difficulties, singularities that can arise when the moving fluid "bounces" into the stationary fluid? Shocks, instabilities?
Normally when I work with reactive flow, I do not take into account gravitational forces, that is, whether the reactor is horizontal or vertical. I suppose gravity comes into play in the unreacting flow case.
I would be grateful upon your suggestion of what model I should use, numerical method that needs to employed and any kind of tips.
If this is not the forum the thread should have been started, please feel free to move it to the appropriate forum.
Thank you for taking your time.
Best regards...
Niketas Konstantinidis
National Technical University
School of Chemical Engineering
Athens, Greece