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Discussion starter · #21 ·
Discussion starter · #22 ·
Ok, the runners are now all "equal" length. They are off by a few thousandths of an inch. I'll run a flow simulation on it over the weekend.

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Discussion starter · #24 ·
ToeBall said:
If you guys want to, I've got access to the entire Dassault suite indirectly, so if you want to try tackling a twin scroll manifold, I can definitely get the simulations run.
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Hey ToeBall, sent you an IM
 
Discussion starter · #25 ·
I am tired of not being able to find a high quality oil drain pan/container (the container used when changing your cars oil), so I threw together a concept today. I have never been able to find one that I could say I actually liked to use, so here is my solution:

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Its dimensions are 16"x16"x5", it'll be made from two pieces of 11 gauge (.120" thick) SS, and it'll be entirely tig welded together. It also has two Threaded SS plugs with double o-ring seals to keep the oil in the pan during transport. Before I pull the trigger on building this, is there anything you guys can think of that I should change or improve?
 
Discussion starter · #27 ·
B0000rt said:
Question for you guys, would an equal length header be beneficial for the stock turbo?
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Sure, but with a turbo of this size (small) I couldn't see there being a large enough improvement to justify spending the time and money to build one. Plus, you wouldn't be able to make a manifold like the one posted above, you would have to integrate the turbine housing into it as well.
 
Discussion starter · #29 ·
Discussion starter · #30 ·
So its been a slow morning, thus I have time for a little flow simulation action. This is an extremely well balanced manifold.

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All you are seeing in the above pictures is the area of flow itself, not the manifold surrounding it.
 
Discussion starter · #33 ·
Thanks guys :) Just updated the head flange.

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and the final image hints at another project that I'm working on.

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:D Updates soon.
 
#34 ·
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#35 ·
So am I to believe that the flow through that manifold is completely laminar?

We both know that is not true, so what are those flow lines showing? What assumptions are made? Are those velocity lines, pressure lines, temp...

Very cool use of CAD, but depending on the simulation run and the assumptions it could just be a worthless pretty picture.

We always warn our managers at NASA that while CFD makes a pretty picture on a powerpoint slide without concrete assumptions and testing to back up those assumptions, it should only be used as an initial proof of concept tool.

CFD is great, but too many people believe what it puts out blindly without knowing the physics model the software uses.
 
#37 ·
AAC Welder said:
So its been a slow morning, thus I have time for a little flow simulation action. This is an extremely well balanced manifold.

Image


Image


All you are seeing in the above pictures is the area of flow itself, not the manifold surrounding it.
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I'm out of town for a couple of weeks and you manage this!?! Very awesome! Put a T4 flange on the end and sign me up!
 
#38 ·
SCRAPPYDO said:
We always warn our managers at NASA that while CFD makes a pretty picture on a powerpoint slide without concrete assumptions and testing to back up those assumptions, it should only be used as an initial proof of concept tool.

CFD is great, but too many people believe what it puts out blindly without knowing the physics model the software uses.
Click to expand...
Pretty much the same can be said for all CAE (Computer Aided Engineering) tools. They all make pretty pictures that impress most everyone in the room, but you need to understand the boundaries, settings, scales, etc. I am not FEA expert, but I do run simulations a few times a year, and making sure the analysis is setup correctly is the hard part.

This kind of forum is not usually where you would get into that level of detail, but maybe this particular post could be an exception. Maybe AAC Welder is an expert CFD user, or maybe he could use the collective help of the community.
 
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Discussion starter · #39 ·
ecirwin said:
Pretty much the same can be said for all CAE (Computer Aided Engineering) tools. They all make pretty pictures that impress most everyone in the room, but you need to understand the boundaries, settings, scales, etc. I am not FEA expert, but I do run simulations a few times a year, and making sure the analysis is setup correctly is the hard part.

This kind of forum is not usually where you would get into that level of detail, but maybe this particular post could be an exception. Maybe AAC Welder is an expert CFD user, or maybe he could use the collective help of the community.
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ecirwin said:
So, is this showing pressure drop, flow length, or what?

I also work with SW daily, but we don't do anything that requires Flow Analysis.
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SCRAPPYDO said:
So am I to believe that the flow through that manifold is completely laminar?

We both know that is not true, so what are those flow lines showing? What assumptions are made? Are those velocity lines, pressure lines, temp...

Very cool use of CAD, but depending on the simulation run and the assumptions it could just be a worthless pretty picture.

We always warn our managers at NASA that while CFD makes a pretty picture on a powerpoint slide without concrete assumptions and testing to back up those assumptions, it should only be used as an initial proof of concept tool.

CFD is great, but too many people believe what it puts out blindly without knowing the physics model the software uses.
Click to expand...
The flow simulation you are seeing above is an oversimplified study. It was setup in all of 5 minutes and it only took about a minute to solve. If this was the exact model that was going to be used for a part to be manufactured, much more detail would have gone into the setup of the study. I'll give you the assumptions used in the above study to help clear things up. Only "air" is flowing through the tubing (not specified gases and other particles), the internal walls of the tubing have no surface finish (perfectly smooth), the inlet ports are all flowing the exact same volume of air, at the same pressure, and at the same moment in time, and the air entering the tubing is not turbulent. There are other inputs that have oversimplified as well, but you get the idea.

Clearly this is not ideal if you need exact flow values ect, but I only had a small window to run a quick study, and this is just for fun. I can't tie up my primary work computer during the day while a study runs for hours on end. We do have dedicated workstations used only to run resource and time intensive studies, but these are reserved for projects from paying customers, not for my quick side projects. :)

A study is only as good as the assumptions used in its setup, trust me, I understand this. I have to explain this to my customers and students ALL the time. It is also important to run real world tests to verify anything you do in a simulation before going into production of a part. I would never assume that a new seat belt buckle design was safe just because a simulation told me so. Real world testing should always be used once a design has been refined as best as it can be using just simulations alone.

Having said that, what plots is everybody interested in seeing? Flow trajectories, flow animations, pressure animations? The plots I posted earlier show pressure, both on the surface and internally using lines.
 
Discussion starter · #40 ·
ToeBall said:
I'm out of town for a couple of weeks and you manage this!?! Very awesome! Put a T4 flange on the end and sign me up!
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Thanks dude! :) I will be building a manifold for myself in the next month or so, if you'd like for me to build one for you just let me know. I already have T4 flanges machined to match my merge collector sitting in a box somewhere, I just need to find a source for head flanges or a local shop to machine some for me.
 
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