I wonder. With the ban on OT-EBD maps now; how possible would it be; when these 1.6L engines come out; to work around that?
Would it be possible for example; to substitute it with the pressure blow-off valve?
Very unlikely in my view. Waste gates may not even exist on those designs because any surplus of turbine power over the compressor demand would be sapped by the MGUH. The MGUH is supposed to contribute 90 kW to the motive power. If they have a waste gate at all it would merely be a safety feature.raymondu999 wrote:I wonder. With the ban on OT-EBD maps now; how possible would it be; when these 1.6L engines come out; to work around that?
Would it be possible for example; to substitute it with the pressure blow-off valve?
At boost, the compressor is typically cold enough to transfer heat from the compressed air to the turbocharger.johnny99 wrote:Heat transfer is neglible. Most if not all heat is generated by compressing the air.
Compressor housings in CNC machined aluminum is something you usually doesn't see. Cast aluminum or magnesium is more common, usually combined with a CNC machined compressor wheel, typically from a forged billet of 2000-series aluminum. Titanium are used in some high boost applications due to the heat, but with low boost an aluminum wheel is probably lighter. Turbine housings of racing turbochargers are often made as a thinwall casting in HK30 stainless (a material commonly found in jet engine exhausts) while bearing housings can be made of titanium; Garrett offer that option on the TR30R for instance. The turbine wheel is usually investment cast in Mar-M 247, a directionally solidfied superalloy.scarbs wrote:I meant the outer compressor casing is CNC Alu. The turbine casing & HERS appeared to be steel\Ti (?)
The cylinderwalls are normally coated with Nikasil or similar, which is silicon carbide in a nickel matrix. Coatings on pistons are normally not ceramic. In F1 DLC is the standard for pistons these days. The ones I've seen have had the crown uncoated, that allows the piston to stand on the crown when being coated. The piston is polished before being coated.Dragonfly wrote:IIRC Ferrari used ceramic coating for the cylinder walls and pistons in their V10's. I remember reading back then about Shell developing special lubricants as the traditional ones lead to the coating delamination.
Lon time since though, may be wrong.
I think ceramic parts were outlawed with the V8 engine rules.
One main reason for using teflon tend to be to reduce noise.strad wrote:Many years ago, Rand made some pistons for my Triumph that were Teflon impregnated. Not coated but actually a mil into the aluminum. It made for fricton on the order of wet ice on wet ice..I wonder if modern F1 does something similar
Xylanhardingfv32 wrote:The Jag/Ford Cosworth V10 piston I have has a green coating on the skirts. Not sure what that would be.
The "idle" they mean is a raised engine speed with the 'umluft' system going.strad wrote:Well WB and other people doubted me...Ok it wasn't 4 Bar,,it was only 3..I found the tape..Holm86 wrote:4 bars at idle? dont believe that....
click photo for video
You still have to deal with the possebility of turbine choke at high engine speed. Make the turbine large enough to offer a low expasion ratio (less exhaust backpressure) at high speed and the expansion ratio can be a bit too low at lower engine speeds. So a wastegate can still be needed.WhiteBlue wrote:Very unlikely in my view. Waste gates may not even exist on those designs because any surplus of turbine power over the compressor demand would be sapped by the MGUH. The MGUH is supposed to contribute 90 kW to the motive power. If they have a waste gate at all it would merely be a safety feature.
Good point. I was trying to summarize it under safety feature to make it clear that under normal circumstances you would design the system for use without a substantial waste gate stream.Edis wrote:You still have to deal with the possebility of turbine choke at high engine speed. Make the turbine large enough to offer a low expasion ratio (less exhaust backpressure) at high speed and the expansion ratio can be a bit too low at lower engine speeds. So a wastegate can still be needed.WhiteBlue wrote:Very unlikely in my view. Waste gates may not even exist on those designs because any surplus of turbine power over the compressor demand would be sapped by the MGUH. The MGUH is supposed to contribute 90 kW to the motive power. If they have a waste gate at all it would merely be a safety feature.
It was for friction reduction AND it changes the bearing relationship from being the piston to being the cylinder wall which increases longevity by a ton.One main reason for using teflon tend to be to reduce noise.
After searching and finding this thread I understand a whole lot more now.WhiteBlue wrote:http://de.zinio.com/pages/RacecarEngine ... 8379/pg-62
Race car engineering has a nice article
I thought that this would be the best application for F1. Particularly if you use an axial turbine.
This is what RCE thinks was originally intended as the 2013 engine.
Here is some text with data. The engine was supposed to have 580 hp without compounding. After the V6 decision the available power will be less. If they set a boost limit to force the engines from 8,500 rpm up to 15,000 the power will be less again. The simulation shows that the original engine plan called for seriously lower revs.
You are one of the happy few. Most people don't seem to realize that you have to reduce boost and fuel flow per stroke in order to meet the absolute fuel flow limit when you increase the rpm above 10,5000. It means that you have to decrease the torque at the same ratio that you increase the revs.pgfpro wrote:I also can see that there's not going to be much benefit for running anything above 10500rpm. Back pressure is going to increase above 10500rpm do to the fact intake manifold pressure will have to be decreased because of the fuel rule. This will make turbine flow decrease at higher rpm also. In turn less turbine energy to extract.