Chinese Aviation Industry
- Thread starter FriedRiceNSpice
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It is only using 4.5kg of fuel.
Guess why? The storage is low density. You need a huge heavy fuel tank to store just that amount. It is using compressed hydrogen storage.
by78
General
EHang's EH-216-S passenger eVTOL has conducted its . The unmanned aircraft flew passengers around the scenic Jiulong Lake in the Huangpu district of Guangzhou. So far, EH-216-S has completed more than 42,000 safe flights. Guangzhou will soon open its first tourism route for unmanned aircraft, with more than a dozen stops along the way.
The price tag for the EH-216-S eVTOL is ¥2.39 million, or $336,000.
Do you have a source on that fuel tank?
From the original article:
"The aircraft is 8.2 meters in length and is capable of high-pressure gas hydrogen storage of up to 4.5 kilograms. The cruising speed of this aircraft is 180 kilometers per hour."
In other words it uses compressed hydrogen storage. Which has really low density and requires heavy fuel tanks.
"The aircraft is 8.2 meters in length and is capable of high-pressure gas hydrogen storage of up to 4.5 kilograms. The cruising speed of this aircraft is 180 kilometers per hour."
In other words it uses compressed hydrogen storage. Which has really low density and requires heavy fuel tanks.
I was asking if you had a source to show that China is using heavy fuel tanks to store compressed hydrogen. I found this French one, which does indeed seem heavy in comparison to the weight of fuel, it stores 4.2kg of fuel, and the tank weighs 215kg. I think Chinas material science can do better than this though, and I am not sure if this is even considered heavy.
Here are some compressed H2 tanks that are Chinese and light enough for UAVs..
It is just plain physics. The higher the pressure you want to use to store something at, the stronger the pressure vessel walls need to be. You basically need thicker walls. Then there is the fact the volumetric energy density of hydrogen compared to aviation grade kerosene is, well, crap. So the tank needs to be huge in volume. The larger the inner volume, the more tank surface area and weight.
Hydrogen at standard pressure and temperature has like 20x less volumetric energy density than natural gas and 2000x less than aviation grade kerosene at the same pressure and temperature. If you compress the hydrogen it might use 200x less volume. But it will still take more volume than kerosene by like an order of magnitude. And it will need much heavier tanks because of the larger volume required to store the same energy, and the thicker walls you need to withstand the extra pressure.
These slides have a lot of information on the technology.
Hydrogen at standard pressure and temperature has like 20x less volumetric energy density than natural gas and 2000x less than aviation grade kerosene at the same pressure and temperature. If you compress the hydrogen it might use 200x less volume. But it will still take more volume than kerosene by like an order of magnitude. And it will need much heavier tanks because of the larger volume required to store the same energy, and the thicker walls you need to withstand the extra pressure.
These slides have a lot of information on the technology.
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The question is if 4kg of hydrogen gas can be useful enough for the tasks of general aviation, particularly to train pilots.
The advantage of using hydrogen will come later as emissions regulations tighten in China and other markets. At least you can start building up the supply chains and perform R&D work.