CFD Simulation of an FSAE Restrictor

Flow conditions in the Restrictor at 12000 rpm. Engine is a 600cc 4cyl n/a. Mach number is shown during one cycle.

Category:

Autos & Vehicles

Tags:

• FSAE
• Formula
• Student
• SAE
• Restrictor
• CFD

[FuriousCow]

Hi

What was your mesh like for this simulation? Did you use GAMBIT and Size functions for refinement at the walls to display the boundary layers? Looks good

[Hellbier]

The meshing was done in Gambit. For the restrictor and the intake runners a structured hex mesh was used and hexcore meshing for the manifold.

[ArosaMike]

Did you do the work on this? If so....did you find that adding the really long diffuser had a big effect? Our restrictor is based on a FYP from a few years ago that discovered that due to the intake pressure waves, the diffuser didn't really have much of an effect. We got slated at FSG though for not having the project with us :( I need to look into it more!

[Hellbier]

Yes I did the simulation. On steady state testing the long restrictor works better than a short one, but I have not tried a restrictor with a bigger opening angle in a transient simulation yet.

The long restrictor provides a relatively even flow to the plenum which helps to minimize variations between the cylinders.

[eaxnitro]

@KevanB You would then have a fuel and air mixture travelling through that space which would mean less than maximum air flow into the engine.

[KevanB]

@eaxnitro Could also use E85 and have a single injector upstream of the throttle body for a cooling effect. That is, if any benefit would be seen, probably only useful for turbocharged applications where intake air temps are high enough to see a benefit.

[eaxnitro]

Shame the fsae rules only let you cool the intake air through intercoolers using ambient air. More power could be made getting that intake temp down thereby increasing air density. Something like the ammonia cycle. Use the exhaust heat in that ammonia refrigeration cycle to cool the intake..... As I said, rules of fsae forbid it.