Turbo mesh

[user 5942]

Hello,

Some people (even on this forum) recommended installing an inter-cooler, not only for the benefits gained by having an inter-cooler but also because it can protect the engine if something happens to the turbo.

Not sure if this idea has been raised before, but has anyone thought of sticking some aluminium mesh between the engine intake and the turbo? Would like to get the "security" offered by the inter-cooler but without spending the money.
(for the matter, the performance gain from the inter-cooler is of no interest to me).

Would love to hear some ideas/comments.

Thanks!

 

[Bluenavara]

Go for the intercooler anyway.

Even if performance gains don't interest you, see the ic as a thermal safety, dropping diesel killing egts proportionally with the drop in intake temps.

The added safety against the turbo grenading is indeed the second safety bonus. Also realize that adding some sort of mesh screen somewhere in the intake amounts to a FOD hazard of sorts...

 

[sparra04]

it would have to be fine mesh to stop small bits
too much restriction i think

 

[Krankin]

it would have to be fine mesh to stop small bits
too much restriction i think

the tubes in the ic aint that fine

 

[Dave]

http://www.navara.asia/showthread.php?t=8920

Read this thread.

Intercooling can be done cheap.

Worth the effort and more worthwhile then the mesh.

 

[Krankin]

http://www.navara.asia/showthread.php?t=8920

Read this thread.

Intercooling can be done cheap.

Worth the effort and more worthwhile then the mesh.

great alternative to a new setup.........tho mesh is better than nothing at all

 

[sparra04]

the tubes in the ic aint that fine

true
the old buick v6 commodores had a very fine mesh in the intake/airflow sensor
but a turbo diesel has a lot more constant air volume
interesting

 

[Old.Tony]

The other difference with the intercooler is that there's a significant distance between turbo & manifold compared to non-intercooled, so there'll be more settling of finer particles. Also, the intercooler will act something like a catch can for even the finer debris that, even if it makes it through the cores of the intercooler, will mostly impact on the far side of the intercooler and fall to the bottom.

Hopefully, of course, by the time sufficient particles have built up in the bottom of the intercooler to start feeding back up to the intake manifold (say 3-4 days of constant driving) someone would have noticed that the turbo had disintegrated.

 

[tweak'e]

the simple problem of adding mesh is inlet restriction and speed of airflow.
to add some sort of filter you will have to make it bigger than the stock tubing otherwise it will be a restriction.
the advantage of the intercooler is the air slows down due to the ic's big size. that helps a lot in stopping bits go through.

 

[Krankin]

So is nothing better than something?

 

[tweak'e]

So is nothing better than something?

almost.
restricting the intake with mesh would cause more problems, might even cause the turbo to fail.
you could still make a big mesh trap, but cost of that would be close to an IC anyway.

i would just bite the bullet and go fit an IC.
but you can do the easy stuff first, butterfly mod and let the turbo cool down before engine shutoff.

 

[DieselTuner2]

...

 

[Krankin]

the simple problem of adding mesh is inlet restriction and speed of airflow.
to add some sort of filter you will have to make it bigger than the stock tubing otherwise it will be a restriction.
the advantage of the intercooler is the air slows down due to the ic's big size. that helps a lot in stopping bits go through.

so its bad adding mesh cause it slows down the airflow speed,
but,
its ok when the IC slows down the airflow.

???????????????????????????????????????????????


.

 

[Krankin]

its an extremely bad idea.

drastically reducing flow.

is it seriously that fatal??


Does an IC provide no impedence at all?

 

[jace3.0td]

this be any good? http://www.ebay.co.uk/itm/NISSENS-I...arts_Vehicles_CarParts_SM&hash=item48416110ae

 

[Old.Tony]

I think the IC is going to slow down the flow but that's part of the idea. It's half the reason why the IC is so large. Back to elementary fluid dynamics - with constant pressure, if you increase the volume, you decrease the velocity. With the flow moving slower, you have more time for heat to exchange = cooler air. As the volume decreases, the velocity picks up again.

The IC will make for some turbo lag - it's unavoidable. But with the other benefits, it's something we ought to be able to live with.

 

[Krankin]

I think the IC is going to slow down the flow but that's part of the idea. It's half the reason why the IC is so large. Back to elementary fluid dynamics - with constant pressure, if you increase the volume, you decrease the velocity. With the flow moving slower, you have more time for heat to exchange = cooler air. As the volume decreases, the velocity picks up again.

The IC will make for some turbo lag - it's unavoidable. But with the other benefits, it's something we ought to be able to live with.

but wasnt it stated on another thread that there is a pressure drop on the other side of the IC...and take away the cooling effect for a moment, wouldnt the flow be better without the impedance of the IC and all the extra piping /bends needed for the IC install?

disregarding all the above for a moment, the question is about saving the engine from a grenading turbo

 

[Old.Tony]

but wasnt it stated on another thread that there is a pressure drop on the other side of the IC...and take away the cooling effect for a moment, wouldnt the flow be better without the impedance of the IC and all the extra piping /bends needed for the IC install?

disregarding all the above for a moment, the question is about saving the engine from a grenading turbo

Jim, you are absolutely right. Anywhere there's a restriction, a bend or even a sensor in the pipe (like the MAFS), there's an impediment to flow. Turbulence is created around sensors which impedes flow. Extra energy is required to push the air through a narrowing of the tube and the best example is where the air exits the intercooler, although other "choke points" exist, in the D40 there's a metal restrictor in the air hosing about 30cm away from the turbocharger's charge air outlet.

In the greater scheme of things though, these (relatively) small disturbances or restrictions don't have enough influence to concern us. If we were trying to get 50psi of boost in race trim then we might be talking differently here, but we're talking about plodding along on a suburban street and losing 1 or 2 horsepower makes no difference.

And as for saving the engine from a grenading turbo ... I think the intercooler actually gains a few percent more power than it loses in restriction, so it's still an advantage to have one - for BOTH reasons.

 

[Krankin]

Jim, you are absolutely right. Anywhere there's a restriction, a bend or even a sensor in the pipe (like the MAFS), there's an impediment to flow. Turbulence is created around sensors which impedes flow. Extra energy is required to push the air through a narrowing of the tube and the best example is where the air exits the intercooler, although other "choke points" exist, in the D40 there's a metal restrictor in the air hosing about 30cm away from the turbocharger's charge air outlet.

In the greater scheme of things though, these (relatively) small disturbances or restrictions don't have enough influence to concern us. If we were trying to get 50psi of boost in race trim then we might be talking differently here, but we're talking about plodding along on a suburban street and losing 1 or 2 horsepower makes no difference.

And as for saving the engine from a grenading turbo ... I think the intercooler actually gains a few percent more power than it loses in restriction, so it's still an advantage to have one - for BOTH reasons.

Oh, I'm in no way trying to bag out the fitment or use of an IC, I have one on and if I had an older nav i would use some s/s screen untill i could get a suitable IC fitted, I'm just arguing the merits of installing the said screen in leiu of an IC and that I cant see the screen providing more impedance than an IC and all the associated extra piping lengths & bends,
unless of course one fitted a couple of layers of flywire.

 

[Old.Tony]

Oh, I'm in no way trying to bag out the fitment or use of an IC, I have one on and if I had an older nav i would use some s/s screen untill i could get a suitable IC fitted, I'm just arguing the merits of installing the said screen in leiu of an IC and that I cant see the screen providing more impedance than an IC and all the associated extra piping lengths & bends,
unless of course one fitted a couple of layers of flywire.

If you don't account for the cooling effect of the intercooler, then the screen would win hands down in terms of efficiency. But as soon as you DO account for the cooling effect (and the resulting power increase) then the IC beats a screen by a country mile.

To make the screen really effective, you'd need to put it in a large container, large enough so that there were enough holes in the screen to more than make up for the cross-sectional area of the tube that didn't have any screen in it. This wouldn't get rid of the turbulence and the flow reduction close to the surface of the mesh (think in terms of laminar flow) but it would negate MOST of the restriction.

I guess it'd have to be a bit like a bucket with the screen in the middle, and the air pipe entering the lid and exiting through the bottom - and even then it's going to have similar issues to the IC, because there's nowhere near the engine that you could fit a bucket.