New 2015 fuel flow Directive

[bdr529]

I just had another thought. Reducing the pressure in the lines will cause lighter components of the fuel to vaporise if the pressure is reduced below the vapor pressure of that component. This would potentially allow ALL THE FUEL between the flow meter and the pump at the engine to be used for a short term power boost.

This is intriguing.

A combination of flexing fuel lines, and playing with the pressures, could well give some remarkable "boost".

but surely with the necessary reduction in pressure to cause vaporization, there won't be a big enough pressure gradient for the fuel to be injected?

I'm have a little difficulty understanding this, Where are you having the fuel vaporize? in the fuel line itself or in a separate chamber?

And one other thing what effect if any will the race in Mexico have on the fuel usage see how it is over 1 mile above sea level

[Vortex37]

Whilst an accumulator is not considered legal, a 'generously sized' fuel filter or similar, could pass inspection. Remember we are not talking about eliminating the purpose of the flow restriction, but a very small short term extra boost in output, at appropriate points. A gain of 1/10th sec at the exit of a corner or acceleration point, would give a big gain over the whole lap. Not a silver bullet! - the aggregation of small improvements in all areas.

[F1Sidecar]

I'm thinking that active fuel lines are the only way this would work. Some materials can change their properties at a specific resonance. What if the engine revs at 11,300 rpm and that causes a specific resonance that allows the lines to expand and hold more fuel? Its complete pie in the sky but hey, that seems to be the idea here. Oh and chill people. No need for the anger fan boy insults. Its just F1.

[gruntguru]

Based on your old calculation

If someone is scamming the rules, it would be very easy to custom make some "flexy" fuel lines.
Fuel flow is 28 g/s say 35 cc/s. One extra cc per second is a 3% power boost.

Do that means for every 1 cc they are getting 3% of Power boost, so
3% * 30 cc = 90% more boost per liter ??

If they consume the entire 30cc in 1 sec - yes. If the use it over a 10 sec period, the boost would be 9% etc

[Shaddock]

If you had a longish fuel pipe you may be able to get some sort of temporary boost without too much clever trickery. You would need a valve (after the FIA fuel restrictor/sensor) to let air into the fuel pipe so the fuel in the pipe could be 'sucked' into the engine at at greater rate than 100kg/h without pulling more fuel than allowed past the FIA fuel flow meter.

This could be activated half way down a straight for a top end HP boost, when the driver lifts the system then refills and any air expelled via a fuel filter closer to the injectors.

[gruntguru]

All you provided was the results of a basic math calculation, that's not based on any of the real world operating parameters.
For example:
According to the specifications, the flow meter that sits between the fuel pump and the engine is only designed to operate at 20 bar, and is likely to explode above 60 bar. Thus you can't use the fuel pump to build up 500 bar of pressure.
http://www.fia.com/sites/default/files/ ... eter_0.pdf
http://gillsc.com/content/datasheets/gi ... 014?v2.pdf

So the question is, without doing something blatantly illegal like using an accumulator, how would a team get a benefit.

Easy. If the scam involves pressurising the lines for an accumulator effect, you make it work between 0 and 20 bar - or - you add a pump immediately after the flow meter.

If the scam involves reducing pressure to produce a vapor bubble, you restrict the flow through the flow meter to 100 kg/hr eg with a fixed displacement pump or throttling valve immediately after the flow meter. The lift pump at the engine would need to be capable of pulling fuel from the supply line at less than atmospheric pressure. The vapor would need to have a "high point" in the lines to accumulate so the pump does not see vapor at its inlet. The "high point" would be in a hotter section of the fuel lines (a "fuel heater" probably) to ensure vapor bubbles do not form elsewhere in the lines.

With heated fuel (which teams are probably using anyway) the vapor pressure may even be above atmospheric.

[dans79]

I have a feeling if anyone gets caught, the punishment is going to be pretty severe.

technical regulations 5.10.5

Any device, system or procedure the purpose and/or effect of which is to increase the flow
rate after the measurement point is prohibited.

some more rules i found that would make this hard to do.
6.2.5

All components containing fuel at a pressure greater than 10bar must be located outside the
fuel tank.

6.5.3

The use of any device on board the car to decrease the temperature of the fuel is forbidden.

[Sevach]

If Mercedes is gaming the fuel flow rules, it could explain the huge margin in qualy and the smaller one in the race.

On qualifying you are only limited by the fuel flow, on the race you are limited also limited by the 100 kg of fuel for the race which would make using this higher fuel flow a tougher proposition.

[Harsha]

Easy. If the scam involves pressurising the lines for an accumulator effect, you make it work between 0 and 20 bar - or - you add a pump immediately after the flow meter.

If the scam involves reducing pressure to produce a vapor bubble, you restrict the flow through the flow meter to 100 kg/hr eg with a fixed displacement pump or throttling valve immediately after the flow meter. The lift pump at the engine would need to be capable of pulling fuel from the supply line at less than atmospheric pressure. The vapor would need to have a "high point" in the lines to accumulate so the pump does not see vapor at its inlet. The "high point" would be in a hotter section of the fuel lines (a "fuel heater" probably) to ensure vapor bubbles do not form elsewhere in the lines.

With heated fuel (which teams are probably using anyway) the vapor pressure may even be above atmospheric.

So you are saying is they are using the High Pressure to evaporate vapors inside the fuel line and to save some fuel using some point as accumulator and then using them at a later stage

[gruntguru]

If the scam uses a vapor bubble, it would be acchived by having LOW pressure in the lines (or more likely the fuel heater). For extra power, the fuel pressure is reduced causing a vapor bubble in the fuel heater and allowing the liquid fuel to be drawn out of the heater in addition to the 100 kg/hr coming from the tank.

When the engine demand is less than 100 kg/hr, the flow meter continues to see 100 kg/hr - the difference is fuel being used to re-fill the heater.

[Harsha]

If the scam uses a vapor bubble, it would be acchived by having LOW pressure in the lines (or more likely the fuel heater). For extra power, the fuel pressure is reduced causing a vapor bubble in the fuel heater and allowing the liquid fuel to be drawn out of the heater in addition to the 100 kg/hr coming from the tank.

When the engine demand is less than 100 kg/hr, the flow meter continues to see 100 kg/hr - the difference is fuel being used to re-fill the heater.

As far as i understood the engine is always running at 100kg/hr but the at injection it is going different by injecting the extra fuel which stored earlier to gain more power. is that right

[Jolle]

Basically having the fuel line after the fuelflow meter and before the injectors/high pressure pump expand like a balloon. This is so simple in concept that I expect that all three engines do this.

Mercedes is of course the most likely one, because they are up front (plus the Fire in Lewis his engine at the Hungaroring) and it would explain why the Renault engines have less power now then in 2014 (because of the new directive they gone for solid fuel lines now).

Bare in mind that some level of cheating, or finding loopholes in the rules (like flexing wings) has always been a big part in F1. The rule is: wings should not flex, the way it works: the wing should not flex under a load of 100kg. This is the same: fuel must not exceed 100kg/h at the measure point. They don't say anything about right after.

[SiLo]

Basically having the fuel line after the fuelflow meter and before the injectors/high pressure pump expand like a balloon. This is so simple in concept that I expect that all three engines do this.

Mercedes is of course the most likely one, because they are up front (plus the Fire in Lewis his engine at the Hungaroring) and it would explain why the Renault engines have less power now then in 2014 (because of the new directive they gone for solid fuel lines now).

Bare in mind that some level of cheating, or finding loopholes in the rules (like flexing wings) has always been a big part in F1. The rule is: wings should not flex, the way it works: the wing should not flex under a load of 100kg. This is the same: fuel must not exceed 100kg/h at the measure point. They don't say anything about right after.

I thought the fire in his engine was related to the batteries, which is why it burned for so long?

[dans79]

They don't say anything about right after.

they do!

technical regulations 5.10.5

Any device, system or procedure the purpose and/or effect of which is to increase the flow
rate after the measurement point is prohibited.

[Jolle]

They don't say anything about right after.

they do!

technical regulations 5.10.5

Any device, system or procedure the purpose and/or effect of which is to increase the flow
rate after the measurement point is prohibited.

Well, the regs also say, all bodywork (except drs) should be rigid. It's really that's it's now allowed its bending rules with how it's measured.