I wonder how the metering device will work, is it based on mass or volume?WhiteBlue wrote:Fuel mass flow is in the technical regulations. It is unchanged vs the last edition from December 2012 in todays new release.
Why I suspect it could still be about measuring volume-flow.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.
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they could use a coriolis meter and get proper mass flowxpensive wrote:Why I suspect it could still be about measuring volume-flow.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.
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Please elaborate?langwadt wrote:they could use a coriolis meter and get proper mass flowxpensive wrote:Why I suspect it could still be about measuring volume-flow.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.
...
http://en.wikipedia.org/wiki/Mass_flow_ ... flow_meterxpensive wrote:Please elaborate?langwadt wrote: they could use a coriolis meter and get proper 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 tankWhiteBlue 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.
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.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.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 tankHolm86 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.