Invisible ls3 head demo

[Warp Speed]

Also, knowing how the model was formed would help.
Is this done with steady state data at a given depression, or based on pressures and differentials taken from a running engine at each lift shown?
It would also be nice to include the length of the full intake tract in the model.

[Frankshaft]

Nope, there are no pressure waves present during the clear flow bench test, just continuous flow.

At least those Lucas Oil Stabilizer displays at the autoparts store show how to increase windage. You know those gear to gear displays.

Based on the CFD image what would you guys change on this head to improve it?

What would you do? For me, without any details on the imaginary port, I don't know. Looks sorta like the port I worked on for my buddies EZ go golf cart. Kinda funny actually, it kept pulling until it floated the valves.

[Carnut1]

Also, knowing how the model was formed would help.
Is this done with steady state data at a given depression, or based on pressures and differentials taken from a running engine at each lift shown?
It would also be nice to include the length of the full intake tract in the model.

Warp, I asked nearly the same question of DV this weekend and what he thought would change on this artwork at engine operating pressures. This is one of his pics he uses.

[Carnut1]

Also, knowing how the model was formed would help.
Is this done with steady state data at a given depression, or based on pressures and differentials taken from a running engine at each lift shown?
It would also be nice to include the length of the full intake tract in the model.

Warp, I asked nearly the same question of DV this weekend and what he thought would change on this artwork at engine operating pressures. This is one of his pics he uses.

I should add original was developed at 25" depression.

[GARY C]

Also, knowing how the model was formed would help.
Is this done with steady state data at a given depression, or based on pressures and differentials taken from a running engine at each lift shown?
It would also be nice to include the length of the full intake tract in the model.

Warp, I asked nearly the same question of DV this weekend and what he thought would change on this artwork at engine operating pressures. This is one of his pics he uses.

I should add original was developed at 25" depression.

(CFD) illustrations from Dr. Rick Roberts of Edelbrock. The port is a prototype for one of Edelbrocks’s high-performance heads.
https://www.musclecardiy.com/cylinder-h ... s-part-10/

[SchmidtMotorWorks]

Based on the CFD image what would you guys change on this head to improve it?

First of all, the CFD simulation needs to be performed correctly, the example shown simulates a flow bench (not an engine) in that the flow runs into an cylinder that is open at the bottom.
If the simulation is set-up with a piston, (and even better if the top of the piston) the flow trajectory is much different, especially in the chamber.

Once you get the geometry set up, then you have to set-up the pressure properly, based on data from a 1-D simulation.
During overlap that includes simulating the flow with both valves open and the pressures in each of the ports.
The higher pressures will also show different flow trajectories than a flow bench and show issues that a flow bench cannot.
Obviously the trajectories that occur when both valves are open cannot be simulated with a flow bench; and even if they could, you would not be able to measure them.

Then in both a flow bench and static CFD that simulate static flow, (flow that is continuous) the simulation will show much higher swirl (and similar circular flow) than actually occurs in an engine. This is because a static simulation provides opportunity for the circular flow to build and grow whereas in reality in an engine it does not.

To get high fidelity simulation, you need to have dynamic CFD, preferably with moving boundaries (moving piston and valves).

Also, the visualization of the CFD needs to show sections that cross the flow volume, both along the duct and across it to see what is going on.

You won't find much on the web showing examples, but this video from Fluent gives some insight.

https://www.youtube.com/watch?v=kZ_iXXIAJis


If you are a student, it it is possible to get software to learn it for free, on very good software.

If you are not a student there are still low cost and free options but the software requires a lot more effort and is not as sophisticated.

It is very important to understand that not all CFD is equal, the range of capability and accuracy ranges from very basic that you can find it's limits in a few days, to something that takes a decade to make full use of.

[GARY C]

The screen shots were used to show potential problem areas to demonstrate what can be learned from it.

Jon the vid in the link is in no way a real representation of a runner or combustion chamber so it could not represent and usable info But it still shows the same issue as the actual runner I posted.

[SchmidtMotorWorks]

The screen shots were used to show potential problem areas to demonstrate what can be learned from it.

Jon the vid in the link is in no way a real representation of a runner or combustion chamber so it could not represent and usable info But it still shows the same issue as the actual runner I posted.

You are looking at too macro of a view, the valuable issues will be found in a more micro view.

The way the example image is shown does not provide enough information to be particularly useful.
You need to have at a minimum:
1. zoomed in views
2. arrows or streamlines to show the direction of flow
3. cross section images
4. some length of intake duct added to it (or controlled flow direction)
5. the cylinder modeled with a piston top rather than an open bottom cylinder

There are some clues of problems in the simulation image, but you would need to do the items listed above to properly diagnose them.