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Since the cars will be able to power themselves solely through the ERS, does that mean that they will no longer have to fear stalling? And how will this power be sent to the wheels (if it is sent through the transmission, then they would have to be able to turn the ignition on (after stalling) and off (entering the pit, saving fuel in slow corners))? I haven't gotten through the regs yet, but I'm to eager to hear any ideas in this direction...thanks!

WhiteBlue wrote:Fuel mass flow is in the technical regulations. It is unchanged vs the last edition from December 2012 in todays new release.

I wonder how the metering device will work, is it based on mass or volume?

Yes I'm aware that the rules says mass-flow, but anyway.

http://www.gillsensors.co.uk/content/fu ... ensor.html
http://en.wikipedia.org/wiki/Ultrasonic_flow_meter
It will sit in the fuel tank and it will be measuring the mass flow by an ultrasonic signal. It relies on frequency shift or Doppler effect to measure speed from which it calculates volume flow and ultimately mass flow. For the purpose of good accuracy the regulations also require temperature and pressure measuring of the homologated fuels. The fuel properties are well known.The measuring principle is analogue and cumulative. A digital interface will be connecting the device to the FiA data logging system via a multi master broadcast serial bus system such as CAN and successors of CAN.

WhiteBlue wrote: ...
For the purpose of good accuracy the regulations also require temperature and pressure measuring of the homologated fuels. The fuel properties are well known.
...

Why I suspect it could still be about measuring volume-flow.

xpensive wrote:

WhiteBlue wrote: ...
For the purpose of good accuracy the regulations also require temperature and pressure measuring of the homologated fuels. The fuel properties are well known.
...

Why I suspect it could still be about measuring volume-flow.

they could use a coriolis meter and get proper mass flow

langwadt wrote:

xpensive wrote:

WhiteBlue wrote: ...
For the purpose of good accuracy the regulations also require temperature and pressure measuring of the homologated fuels. The fuel properties are well known.
...

Why I suspect it could still be about measuring volume-flow.

they could use a coriolis meter and get proper mass flow

Please elaborate?

xpensive wrote:

langwadt wrote: they could use a coriolis meter and get proper mass flow

Please elaborate?

http://en.wikipedia.org/wiki/Mass_flow_ ... flow_meter

As the regulations states a mass-flow wouldn't that be preferable to measure??? Volume changes with heat. Mass doesn't.

The Gill sensor measures mass flow, but via speed an volume flow. According to the specification the accuracy is ok. I assume that they have a proper internal map of the temps and pressures as well as the individual fuels. So I find nothing wrong with it.

AMuS reported before about homologation process. Here is the official ANNUAL F1 POWER UNIT HOMOLOGATION from 2014 F1 Technical Regulations - Published on 08.07.2013

WhiteBlue wrote:The Gill sensor measures mass flow, but via speed an volume flow. According to the specification the accuracy is ok. I assume that they have a proper internal map of the temps and pressures as well as the individual fuels. So I find nothing wrong with it.

The current spec. says fuel must between 720 and 775 kg/m3 @ 15'C that's quite a span, so I think they would need to measure and compensate every time they put fuel in the tank

The volume of 100 kgs of fuel is alot more at 100° (race temperature) than it is at 15° (fueling temperature) wouldnt you say?

I dont know the exact volume and thermal expansion of race fuel.

But i see a problem if you are measuring volume flow and then calculate into mass flow. Because what temperature are we going to calculate with? Then the FIA needs to monitor the temperature at the exact same place as where the volume is measured. We can't have a standard temperature saying etc. 100°. Because then you could just add fuel coolers and then you have alot more than the 28g/s of mass flow.

langwadt wrote:

WhiteBlue wrote:The Gill sensor measures mass flow, but via speed an volume flow. According to the specification the accuracy is ok. I assume that they have a proper internal map of the temps and pressures as well as the individual fuels. So I find nothing wrong with it.

Holm86 wrote:The volume of 100 kgs of fuel is alot more at 100° (race temperature) than it is at 15° (fueling temperature) wouldnt you say?

I dont know the exact volume and thermal expansion of race fuel.

But i see a problem if you are measuring volume flow and then calculate into mass flow. Because what temperature are we going to calculate with? Then the FIA needs to monitor the temperature at the exact same place as where the volume is measured. We can't have a standard temperature saying etc. 100°. Because then you could just add fuel coolers and then you have alot more than the 28g/s of mass flow.

The current spec. says fuel must between 720 and 775 kg/m3 @ 15'C that's quite a span, so I think they would need to measure and compensate every time they put fuel in the tank

But the FiA know the density for each homologated fuel. The 15°C comes from an assumption of 25°C ambient temperature -10°C that they are allowed to cool the fuel. But the flow is measured in the fuel tank together with the temperature and pressure. So the sensor can calculate the correct mass flow with a complete set of data with high accuracy every time the bus polls a digital read out for the data loggers. That would be several times per second. I doubt that 100°C will ever occur in the fuel tank btw.

Why would you measure the flow in the tank? To get a correct reading of the fuel flow you need to measure the flow as late as possible. This would probably be right before the high pressure DI pump.

If you measure the flow in the tank then you could have a reservoir outside the tank where fuel could build up when you are using less than the max flow allowed. And then you could have a higher flow when fuel is needed. This would mean that the 100kg/h would only be an average fuel flow. And this is not the intention of the rules.

The teams are calculating the consumption by the opening time of the injectors and the number of cycles. With this and the fuel pressure as well as the valve cross section, temperature.

Why are they not using this as it is already done?