TERS : Thermal Energy Recovery System

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
gruntguru
gruntguru
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Re: TERS : Thermal Energy Recovery System

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godlameroso wrote:
Wed Feb 02, 2022 3:33 pm
If normal air were heated to the same temperature as a gasoline + air combustion, at the same rate, would the end result in the pistons and turbine be the same? Or do the combustion products such as CO2 change the density and pressure of the exhaust gases? CO2 for instance has roughly 50% more density than air, NOx as well is more dense than air, as is Sulphur dioxide. Surely the combination of all these reaction products have an effect on the volume and pressure of the exhaust gas stream vs just air.
Apart from the gamma issue raised by Tommy, there is also a volume issue due to the number of moles present. This will even vary for different fuels eg Ethanol or E85 combusts to form a greater number of moles (or molecules) of exhaust gas than normal petrol. This increases exhaust gas volume and increases turbine power for a given engine and operating point.
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Tommy Cookers
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Re: TERS : Thermal Energy Recovery System

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gruntguru wrote:
Thu Feb 03, 2022 9:12 am
Apart from the gamma issue raised by Tommy, there is also a volume issue due to the number of moles present. This will even vary for different fuels eg Ethanol or E85 combusts to form a greater number of moles (or molecules) of exhaust gas than normal petrol. This increases exhaust gas volume and increases turbine power for a given engine and operating point.
isn't this factor - 'a volume issue due to the number of moles present' in effect already covered ?
ie alcohol fuel's inherent (extra) heat value (ie 'power') for a given air mass is (broadly ?) an equivalent
this (stoichiometric-mass) heat value ie power of ethanol is c. 4% more than gasoline's - and methanol's is c.10% more
(though their heat value ie power per given fuel mass as in F1 is of course lower)

but except at the dragstrip .....
75% or more of the cylinder charge is an inert 'working medium' for heat and work flow ....
25% or less is involved in exothermic chemical changes ie combustion
(only c. 0.001% is involved in endothermic chemical changes eg NOx - these being self-limiting)

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godlameroso
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Re: TERS : Thermal Energy Recovery System

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Tommy Cookers wrote:
Thu Feb 03, 2022 10:15 am
gruntguru wrote:
Thu Feb 03, 2022 9:12 am
Apart from the gamma issue raised by Tommy, there is also a volume issue due to the number of moles present. This will even vary for different fuels eg Ethanol or E85 combusts to form a greater number of moles (or molecules) of exhaust gas than normal petrol. This increases exhaust gas volume and increases turbine power for a given engine and operating point.
isn't this factor - 'a volume issue due to the number of moles present' in effect already covered ?
ie alcohol fuel's inherent (extra) heat value (ie 'power') for a given air mass is (broadly ?) an equivalent
this (stoichiometric-mass) heat value ie power of ethanol is c. 4% more than gasoline's - and methanol's is c.10% more
(though their heat value ie power per given fuel mass as in F1 is of course lower)

but except at the dragstrip .....
75% or more of the cylinder charge is an inert 'working medium' for heat and work flow ....
25% or less is involved in exothermic chemical changes ie combustion
(only c. 0.001% is involved in endothermic chemical changes eg NOx - these being self-limiting)
The alcohols have greater heat of vaporization than gasoline. In practice that means greater endothermic component prior to combustion.
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'Tis me, just me.
'Tis me, just me.
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Joined: Tue Jun 12, 2018 5:28 pm

Re: TERS : Thermal Energy Recovery System

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wrong thread. Woops.