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Lokesh February 13, 2008 15:39

Spraying Urea solution in SCR

Can anybody help me regarding Spraying Urea in Catalyst. I putted all the parameters but unable to put injector in SCR Can you suggest how to put injector, because error says that I have not placed any injector.

Do we need to create injector in geometry itself or we can choose it after meshing. I want to put injector at different places in side the pipe. I know the other parameters of injector.


From Lokesh

Andrea February 14, 2008 19:36

Re: Spraying Urea solution in SCR
you can put your injector where you want, just specify what type of numerical procedure you want to use (lagrangian I suppose). Then with the Star-Gui in Lagrangian Multiphase->Droplet Control you can specify if you are simulating a spray injection with atomization or a explicit defined parcel inj.
You don't need to model all the injector geometry: you must define a csys for your injector and place that csys where you want to put the orifice of your injector, in your model. Then in Star Gui->Spray Injection and Atomization (if you choose this option) you must use the csys that you have just defined above.
Hope that help!

Lokesh February 15, 2008 15:29

Re: Spraying Urea solution in SCR
Hi Andrea

I got you, but could you please suggest me how to use csys I used the command says enter ic(1). mesh> then what to do with that

Thanks a lot

From Lokesh

pullaiah g February 16, 2008 02:04

Re: Spraying Urea solution in SCR
Hi Lokesh,

csys is available at the left-bottom corner of PROSTAR mail window, that will display all co-ordinate systems available in your model. there you can define your own location for coordinate system(ie point where you want to inject)as local co-orinate system. and directly specify this co-ordinate system number in defining parameters for injector in Lagrangian multiphase in star-guide. I am also working o similar problem, I want your help in this regard, can u please help in getting properties of urea and HNCO. And can you tell me if you have any data regarding urea decomposition and hydrolysis. thank you.

Andrea February 17, 2008 07:59

Re: Spraying Urea solution in SCR
Using the csys command it's simple:
you can use the GUI Panel on the left of the screen or the text command as (for example) loca,23,cyli,1,0.023,-0.6,0,0,106 where I define the csys23 as local, cylindrical, etc.(you can find info about that command in the help box).
For spray injection the liquid is injected following the z-axis of the csys you want to use, so keep it in mind when you define your coord. system.
For pullaiah, sorry but I have no info about Urea and HNCO...I think that you need to look at some special chem site or archive.

Lokesh February 20, 2008 12:08

Re: Spraying Urea solution in SCR
Hi thanks for help

I am also searching for that. My source is tech papers. If I am able to find them I will post you as soon as possible



Lokesh February 28, 2008 17:43

Re: Spraying Urea solution in SCR

check this paper 2004-01-1944 SAE paper for urea solution properties.

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