Blown Diffuser??

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autogyro
autogyro
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Re: Blown Diffuser??

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I dont see it as funny.
Of course it could be nothing but worth noteing.
Same as the Ferrari miss fire in their promo run that was never explained.

speedsense
speedsense
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Re: Blown Diffuser??

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mep wrote:
I did pay attention to qualifying today, especially the off throttle of the Red Bull in car camera. There is definitely a tonal difference of the engine in off throttle.
hahahahahahaha
You really impress me, you hear a difference between on and of throttle.
I think I know the difference having worked most my life in auto racing, you tend to notice the little things. Specifically I paid attention to the sound of the motor when it was off throttle...tonally it's a different sound than during the race at Valencia, from Webber's car in both cases. Leads me to believe what Scarb's is suggesting, about retarded timing.
There is a difference in pitch....
"Driving a car as fast as possible (in a race) is all about maintaining the highest possible acceleration level in the appropriate direction." Peter Wright,Techical Director, Team Lotus

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WhiteBlue
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Re: Blown Diffuser??

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Scarb's blog wrote:If the overheating issues can be contained, this would be a relatively simple mapping to introduce for another EBD team. As mentioned Renault Sport, Red Bulls engine supplier would have to know about this. Copying the concept, but not the actual SECU code would be quite easy.
I agree with Scarbs on the mapping issue being relevant but I disagree on how it is done. This can't legally be an issue of programming but rather an issue of selecting and uploading the suitable multi dimensional maps. The CAN bus is seriously fast. I have no doubt they can manage to upload those few kb in real time from the steering wheel CPU.

The other more interesting issue here is the question of caloric management. People disagree whether the intake injectors are actually dialed back or rather increased. I tend to think that retarding ignition and reducing fuel flow would be optimal but I don't have the necessary contacts into F1 racing to find out.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

speedsense
speedsense
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Re: Blown Diffuser??

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WhiteBlue wrote:
Scarb's blog wrote:If the overheating issues can be contained, this would be a relatively simple mapping to introduce for another EBD team. As mentioned Renault Sport, Red Bulls engine supplier would have to know about this. Copying the concept, but not the actual SECU code would be quite easy.
I agree with Scarbs on the mapping issue being relevant but I disagree on how it is done. This can't legally be an issue of programming but rather an issue of selecting and uploading the suitable multi dimensional maps. The CAN bus is seriously fast. I have no doubt they can manage to upload those few kb in real time from the steering wheel CPU.

The other more interesting issue here is the question of caloric management. People disagree whether the intake injectors are actually dialed back or rather increased. I tend to think that retarding ignition and reducing fuel flow would be optimal but I don't have the necessary contacts into F1 racing to find out.
The SECU has already a prescribed amount of maps available. Can't add to it. They wouldn't be a reason to send a map from the dash to the ECU, as maps can be stored in the ECU and are automatically selected according to conditions being met without any input from the driver. Turning those conditions on and off, is a simple press of a button or selector on a dial.
It might be interesting to note that power output of the spark plugs can be mapped and altered as well, so that leaner than normal conditions can exist without frying the motor....useful in endurance racing for saving fuel....
"Driving a car as fast as possible (in a race) is all about maintaining the highest possible acceleration level in the appropriate direction." Peter Wright,Techical Director, Team Lotus

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WhiteBlue
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Re: Blown Diffuser??

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speedsense wrote:The SECU has already a prescribed amount of maps available. Can't add to it. They wouldn't be a reason to send a map from the dash to the ECU, as maps can be stored in the ECU and are automatically selected according to conditions being met without any input from the driver. Turning those conditions on and off, is a simple press of a button or selector on a dial.
Thanks, that makes perfect sense. The point that I wanted to make is the difference between the maps and the program. By definition teams cannot be able to make changes to the program of the SECU. They should only be able to make an application to the administrator of the SECU program if they need another functionality. The program administrator should then consider such a request against legality and only implement an upgrade if it is approved by the FiA.

The teams on the other hand should be perfectly able to trigger inactive program functionalities which they may wish to utilize, load different maps or switch between alternative maps that have previously been uploaded.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

speedsense
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Re: Blown Diffuser??

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WhiteBlue wrote:
speedsense wrote:The SECU has already a prescribed amount of maps available. Can't add to it. They wouldn't be a reason to send a map from the dash to the ECU, as maps can be stored in the ECU and are automatically selected according to conditions being met without any input from the driver. Turning those conditions on and off, is a simple press of a button or selector on a dial.
Thanks, that makes perfect sense. The point that I wanted to make is the difference between the maps and the program. By definition teams cannot be able to make changes to the program of the SECU. They should only be able to make an application to the administrator of the SECU program if they need another functionality. The program administrator should then consider such a request against legality and only implement an upgrade if it is approved by the FiA.

The teams on the other hand should be perfectly able to trigger inactive program functionalities which they may wish to utilize, load different maps or switch between alternative maps that have previously been uploaded.
If I remember right and if it was reported correctly, it was Microsoft that wrote the GUI/controller software, replacing Mclaren's controller software, so it's doubtful that there's inactive program functional parts. More than likely the FIA prescribed exactly which functions would be allowed and which won't. Certainly hacking the program would have been a consideration of the FIA. Which is a laugh in certain ways, as Microsoft is one of the most hacked software's in the World.
Having the data acquisition system "act" as an additional controller has been going on for years, but as a spec system, that also would be tightly controlled. Most likely any two way communication between ECU and DA is serial instead of CAN (still used, but not in crosstalk), limiting the communication. IMHO
"Driving a car as fast as possible (in a race) is all about maintaining the highest possible acceleration level in the appropriate direction." Peter Wright,Techical Director, Team Lotus

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WhiteBlue
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Re: Blown Diffuser??

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Microsoft has only payed. They had neither competence not input in this. They just got the right to badge it pretty much like the Ilmore engine was badged Mercedes in 1994.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

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Shaddock
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Re: Mclaren Mercedes MP4/25

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Redbull have their special engine map for Quali, that they can't really use in the race. This may make them untouchable in Q3 for the rest of the season on any track that has a couple of high speed bends.

Mclaren need to start redesigning their manifold, with the possibility of dropping a fuel injector (rules allowing) on the runners to give the car balance off throttle.

The major problem seems to have been heat on the diffuser causing it to distort in shape and not suspension heat related. This should be easier to fix than having to move/relocate wishbones.

autogyro
autogyro
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Re: Mclaren Mercedes MP4/25

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Heat rises and the push suspension on the McLaren looks vulnerable to tranfering heat to the dampers as well as distorting the floor.
Without such a clean aero rear end as the RB, or low mounted dampers etc, it will be a far bigger problem of heat for Macca when sorting the EBD.
I did predict the heat problem as being more acute on the Ferraris but aside from their driver problems (which could be partly balance problems) it looks to have effected the Macca more.

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gcdugas
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Re: Blown Diffuser??

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How does the Renault engine have this special engine map that allows retarded ignition over-run when they use the standard ECU? This is a point I have seen discussed only here.

I think this is disinformation. Any blown diffuser system that needs exhaust gas flow to maintain DF seems like an invitation for handling instability. The driver must be free to correct with the throttle at all times. Methinks the main gain is by purifying the flow going under the rear wing whereas it was previously disturbed by the exhaust gases exiting high enough to change the low-pressure zone under the rear wing elements a bit. Lowering the exhausts (which McLaren used to do in the 1998/99 title winning cars) places the gas flow into the already turbulent area besides the rear wheels and may even help fill the low-pressure void of the rear tire's wake decreasing drag.
Innovation over refinement is the prefered path to performance. -- Get rid of the dopey regs in F1

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WhiteBlue
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Re: Blown Diffuser??

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gcdugas wrote:How does the Renault engine have this special engine map that allows retarded ignition over-run when they use the standard ECU?
The SECU program offers the activation of several alternative and different maps by command of the driver. The sequential parallel shifting of gears together with the engine map is a good example for this. It allows the teams to have a particularly optimized map for each gear.

It is quite conceivable that certain gears - mainly in use in fast corners - can be fitted with two maps which would be selected by an additional switch for Q3.
Formula One's fundamental ethos is about success coming to those with the most ingenious engineering and best .............................. organization, not to those with the biggest budget. (Dave Richards)

CMSMJ1
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Re: Mclaren Mercedes MP4/25

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Shaddock wrote:Redbull have their special engine map for Quali, that they can't really use in the race. This may make them untouchable in Q3 for the rest of the season on any track that has a couple of high speed bends.

Mclaren need to start redesigning their manifold, with the possibility of dropping a fuel injector (rules allowing) on the runners to give the car balance off throttle.

The major problem seems to have been heat on the diffuser causing it to distort in shape and not suspension heat related. This should be easier to fix than having to move/relocate wishbones.
Is that serious? :?:

managed engine braking etc is all fair and well, but fitting fuel injectors downstream of engine is not a serious thought by you is it?

Do you seriously think that anyone is running asymmetrically configured exhausts?

I suspect that the Red Bull car is just less sensitive due to design, rather than any "afterburner" related pie in the sky related thinking.
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Shaddock
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Re: Mclaren Mercedes MP4/25

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CMSMJ1 wrote:
Shaddock wrote:Redbull have their special engine map for Quali, that they can't really use in the race. This may make them untouchable in Q3 for the rest of the season on any track that has a couple of high speed bends.

Mclaren need to start redesigning their manifold, with the possibility of dropping a fuel injector (rules allowing) on the runners to give the car balance off throttle.

The major problem seems to have been heat on the diffuser causing it to distort in shape and not suspension heat related. This should be easier to fix than having to move/relocate wishbones.
Is that serious? :?:

managed engine braking etc is all fair and well, but fitting fuel injectors downstream of engine is not a serious thought by you is it?
Let's say it's 'blue sky thinking' :?

Only one fuel injector per cylinder is allowed in the Regs, so RB retard their ignition to dump fuel into the exhaust to stabilse the flow to the rear.

The exhaust isn't a cylinder, but the injector must inject directly into the side or the top of the inlet port. So no it wasn't that serious suggestion, but getting the exhaust to blow like 'Katrina' off throttle into a blown diffuser is going to be the next major development area.

pete555
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Re: Mclaren Mercedes MP4/25

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autogyro wrote:Heat rises and the push suspension on the McLaren looks vulnerable to tranfering heat to the dampers as well as distorting the floor.
Without such a clean aero rear end as the RB, or low mounted dampers etc, it will be a far bigger problem of heat for Macca when sorting the EBD.
I did predict the heat problem as being more acute on the Ferraris but aside from their driver problems (which could be partly balance problems) it looks to have effected the Macca more.
Heat only rises in air/fluids due to convection,which is only an issue whilst stationary on the grid or for 5 seconds during a pitstop.
The airflow present, even at 15mph will make heat rising via convection irrelevant as to whether components are above or below the exhaust flow.
Last edited by pete555 on 12 Jul 2010, 16:29, edited 1 time in total.

jamesalexw
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Re: Mclaren Mercedes MP4/25

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I really think Mclaren's decision to ditch the low exhausts for Silverstone was the right one. Merc used their blown diffusor at Valencia and had a pretty terrible race, you'd have to assume they did a lot of work between there and Silverstone to fix the issues they had.

This whole line about Mclaren failing to make it work first time is rediculous. RBR failed to make the F-duct work first time out and ditched it after Friday. Ferrari didn't set the world on fire with their blown diffusor. Williams seem to be the only team to really make it work straight out of the box.

Mclaren seem pretty confident that they have enough data from Friday to fix it for Germany, which is where it was originally intended to debut. Lets reserve judgment on the relative difficulty of making it work on the Mclaren till then, if it still doesn't work then I'd say they are in trouble.