Problems with lids when running cosmoflowork

[Cad64]

Hehe, now i got enought post already

 

Yes, and I have deleted all of those meaningless posts you put up in order get your 10 posts. Please do not spam the forum just to increase your post count.

 

If you want to add images to your posts, see here: http://www.cadtutor.net/forum/showthread.php?t=8863

[shift1313]

Unfortunately I think you have a lot of work ahead of you.

 

I know you said this is a project. What are you trying to get from the flow analysis? Cosmos is going to be limited to 50 traces. I think in an object this size it would not show you very much without scaling the model way down.

 

Some of your issues are with the relations between parts. It looks like you are using the constraints to drive how these things are positioned rather than mating geometry. For instance it looks like you have a few joints that are line-line rather than faces touching. When working in software like this you have to put some work into how your parts will be assembled together.

 

What i would do in your case is make the top one piece, bottom one piece, sides, then your roofing.

[kirayat]

Yes, and I have deleted all of those meaningless posts you put up in order get your 10 posts. Please do not spam the forum just to increase your post count.

 

If you want to add images to your posts, see here: http://www.cadtutor.net/forum/showthread.php?t=8863

 

 

 

Sorry about that, i will concern more about the rule.

[kirayat]

Ya i have to admit that my assembly part not really good, i also gt try few times to reassemble it but the result come out still the same. Especially the roof part because it is curly so i only can use plane or line to match it. Cannot match by using line to line? Can you help me assembly it? If cannot then sure my part got problems and have to redraw the part.

[kirayat]

Pls is it anyone can pls help me? i redraw and reassemble my part till wanna blow off... Want to smash my head on to the wall there...

[shift1313]

well i dont see a way to assemble the parts you have to make them usable for a flow analysis without redrawing or editing at least a few of them.

 

You will have to give me a bit more information. What are you trying to show with this project? What are you hoping to get from the flow analysis?

 

The way your drawing is setup the actual roofing part will do nothing for you. the air will enter through the bottom and exit through the top.

 

Here is an image of what the fluid volume shows you assuming your geometry is okay. I drew a quick representation of the shape. Mine was drawn as an assembly With the top all 1 piece, the bottom 1 piece and then the sides.

[kirayat]

First need to thank for your helping because at college there i really can't find anyone that expert in cosmos flowork. Actually I need the result of static pressure and volume flow rate. About my project is to generate electricity using the heat that trap inside the zinc roof. The heat will flow out from the upper outlet that will spin the blade and then from the mechanical energy from the blade will spin the turbine then generate electricity.

[shift1313]

No problem, im glad i can help. Last year i started playing around with cosmos and there really wasnt any help out there so i know what you are going through.

 

Well in SW you need to input these things. For the inlet you have the option of defining the inlet pressure, Volume flow rate or mass flow rate(you can give a temp with these). Your outlet boundary condition depends on the inlet. If you selected pressure for your inlet, you can select Pressure or Volume Flow Rate for your outlet. If you say put 20psi inlet pressure, you need to define your outlet as a lower pressure.

 

If you define your inlet as Volume Flow rate, you can only define the outlet as a pressure. Same thing with mass flow rate. What you will get out of this is a velocity.

 

You can see from the second image above that flow is really relative. The drawing i have is very small compared to your drawing. Mine is like 4.5" x 3" base. On a larger scale those flow traces will show you even less. The Cosmos Xpress isnt really suited for this.

 

Are you trying to apply heat to the roofing and see how the flow changes? Is there anything else you are looking for? If you are simply looking pressures and flow rates I would think this could be done mathematically based on volumes and the size of your inlet/outlet.

[kirayat]

Yup, i'm looking for pressure and flow rates that you mention. Yaya, i trying to apply heat on the zinc roof. Really feel glad that you can teach because need to hand in this project soon...

[kirayat]

Actually about the scale i think no need to follow exactly because we can assume about the size.

[shift1313]

well the numbers i mentioned are ones you need to input, not results that you will get from the simulation. The only results you get from this are velocity. Also the temp you supply is the temp of the air not some ambient temp applied to your structure. FlowXpress is really designed for 1 inlet/1 outlet passages for water or air. So you can see flow patterns and if your geometry gives you the velocity needed etc.

 

For you to do what you are asking you need the full version of Cosmos. There is a Cosmos FlowXpress and Cosmos FlowWorks. Ive unfortunately never used FlowWorks, only read about it, but Flow Express will not give you the results you are asking for.

[kirayat]

O, you mean with Cosmos FlowXpress only can come out with velocity as result? Erm, anyway thanks alot. If you don't mind can you send me the structure that you draw? If you don't mind can attach and send to my mail there (dj_yat@hotmail.com) Regarding to the cosmos floworks need to install alternatively?

[shift1313]

im sorry i cant send you the file. Im using SW09. you can not save as an older version and 08 will not open an 09 file. I dont know what it would do for you anyways. I suggest if you want to use FlowExpress that you draw a simple box either as a part, or an assembly. Then run the flow analysis and see what your variables are and if they will help you or not. This stuff is very picky about the model(for a good reason). Since you are a student you can get Algor Simulation student license for free from EngineersRule.org. but if you only have a few days there is no way you will be able to learn the software in that amount of time.

 

How long have you had for this project out of curiousity?

[kirayat]

This project duration is 3 months, i already done my literature review part now need do simulation part and generate the result. I think is ok because i also got the installer for solidworks 09.

 

May i ask now you are student or already working? I saw your photobucket there your drawing all really nice, i hope you don't mind i view that. Hehe...

[shift1313]

thanks. I work full time doing design/fab work for a university but im still persuing my engineering degree part time.

[kirayat]

Ic, you seem very pro in this field you sure can get it. Erm, so would you mind to send me the file? Because i really have no ideal that how to draw that thing, by the way i'm installing sw09 right now.

[shift1313]

I'm not sure what it will get you but ive added the zip file to this post. The top/bottom were both created using sheet metal features. I drew a rectangle and instead of extruding it, i made it my Base for the sheet metal. Then I just added Edge-flanges at different angles/distances to create the parts.

SWroof.zip

[kirayat]

Ok, thx alot. So you will always be around here? Maybe next time got any problems with cad/cam can disturb you over here~

[shift1313]

of course. well maybe not always but i try to check on the site daily while at work.

[kirayat]

may i ask where is your location actually? now over there is morning?