Simviation Forum - BMW Hydrogen 7

Reply #15 - Jan 2^nd, 2007 at 11:21pm

masmith Offline
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74 Litres of liquid hydrogen

So there is 8kg of Hydrogen which is 8000g

a mole of Hydrogen is 2g and one mole is all ways equal to 22.4 Litres,
so 4000*22.4=89600 litres of Hydrogen gas in the tank...

100kph
200km range

So the car can travle for 2 hours on Hydrogen.... ands there are 120 minutes in 2 hours so the SLPM would be...

747 LPM?

Now devid that by 4000rpm gives 0.19L per revolution

I'm not to sure of my workings so if anyone could check them for me that would be good thanks...

Thanks Matt for the info Wink

Masmith,

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Reply #16 - Jan 3^rd, 2007 at 5:05am

chornedsnorkack Offline
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expat wrote on Jan 2^nd, 2007 at 5:29pm:

Now I understand. The BMW Hydrogen 7 does not have a fuel cell, so SLPM I would think cannot be measured. The car uses a standard petrol engine and used hydrogen in a similar fashion to a LPG converted car. The hydrogen is in liquid form under pressure in a gas tank and then via BMW black magic into gas and then as LPG-ish process injected and burnt.

Matt

Wait - why is black magic needed to turn liquid hydrogen into gas? The liquid should either be warmed to evaporate, or else just injected as liquid since it would evaporate well in fire.

Anyway, what is the Standard for SLPM?

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Reply #17 - Jan 3^rd, 2007 at 7:59am

expat Offline
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chornedsnorkack wrote on Jan 3^rd, 2007 at 5:05am:

expat wrote on Jan 2^nd, 2007 at 5:29pm:

Now I understand. The BMW Hydrogen 7 does not have a fuel cell, so SLPM I would think cannot be measured. The car uses a standard petrol engine and used hydrogen in a similar fashion to a LPG converted car. The hydrogen is in liquid form under pressure in a gas tank and then via BMW black magic into gas and then as LPG-ish process injected and burnt.

Matt

Wait - why is black magic needed to turn liquid hydrogen into gas? The liquid should either be warmed to evaporate, or else just injected as liquid since it would evaporate well in fire.

Anyway, what is the Standard for SLPM?

Black magic.............because if it was that easy, everyone would be doing it Grin

SLPM...........Standard Litres Per Minute

Matt

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Reply #18 - Jan 3^rd, 2007 at 8:10am

expat Offline
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masmith wrote on Jan 2^nd, 2007 at 11:21pm:

74 Litres of liquid hydrogen

So there is 8kg of Hydrogen which is 8000g

a mole of Hydrogen is 2g and one mole is all ways equal to 22.4 Litres,
so 4000*22.4=89600 litres of Hydrogen gas in the tank...

100kph
200km range

So the car can travle for 2 hours on Hydrogen.... ands there are 120 minutes in 2 hours so the SLPM would be...

747 LPM?

Now devid that by 4000rpm gives 0.19L per revolution

I'm not to sure of my workings so if anyone could check them for me that would be good thanks...

Thanks Matt for the info Wink

Masmith,

Hate to throw a spanner into this, but it is my understanding that it is 8kg of liquid hydrogen in the tank, that is equal to 74 litres in gas form. Not sure if that changes things. Undecided

Matt

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B1 Boeing 737-800 and Dash8 Q-400

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Reply #19 - Jan 3^rd, 2007 at 11:28am

masmith Offline
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Well if its 74 litre gas...then

74/120 = 0.6 slpm

and 0.6/4000 = 0.00015 litre per revoluton

Are you shure it is 74 litres of hydgren gas?

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Reply #20 - Jan 3^rd, 2007 at 3:16pm

expat Offline
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masmith wrote on Jan 3^rd, 2007 at 11:28am:

Well if its 74 litre gas...then

74/120 = 0.6 slpm

and 0.6/4000 = 0.00015 litre per revoluton

Are you shure it is 74 litres of hydgren gas?

I read it at the official BMW press release, but I cannot find it again. What I have just found is a write up of a test drive.

Test Drive

On the second page it states that the car uses about 1kg of hydrogen to about 15 miles at cruising speed.

Matt

PETA People Eating Tasty Animals.

B1 Boeing 737-800 and Dash8 Q-400

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Reply #21 - Feb 14^th, 2007 at 4:19am

chornedsnorkack Offline
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Found the data. 160 kg. For 8 kg of hydrogen.

20 to 1 is bad. You want 2 to 1, or better.

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