Thread Drift

[Derswede]

I was involved with an ELF project in Argentina for CNG (compressed natural gas )
fuel for cars. The main feed was your normal gas main. At the station, there was a compressor to allow a steady flow of gas at rated volumes (do not remember that number). Self sealing fittings were used for fuel transfer. The local cabbies loved it, as it was cheaper than petrol. Tank was the big problem, it took up space that could be used for luggage, etc. Tanks were trunk mounted to protect them in case of an accident. Lots of local trucks, buses and the taxis were converted. It has been a couple of years since I have been back, but a quick search shows that it is still commonly used.

At a typical fuel station, you have two main tanks in the ground....one Hi test, one low test. An "STP" (submerged turbine pump) is in each tank, so when you flip up the lever or hit the button on the dispenser, it activates the proper turbine, which pushes fuel up to the dispenser. For mid-grade, the pump activates both turbines and a mixing valve will combine the proper ratio of hi to low octanes to give the mid grade. If, when you activate the gas pump, you hear a motor running, you are at an antique station. Each of those pumps contain a rotary suction pump. Those suck the fuel out of the tank and then dispense it. Only an older station will have those, the "STP" system is much cheaper and more efficient. <<Boring discussion terminated...>>

One problem with tanks for Hydrogen is that most areas ban above ground tanks of more than a certain capacity (100 gal or so). At least a tank leak would be less contaminating than a petrol leak.

Derswede

 

[Aesquire]

And we only had one explosion at the airport tank so far!

Sure, that's a 100% failure rate per station, but we only have one. It was refilled a bunch of times before the fire. The same city has lots of gasoline stations and only a few burned.

Hydrogen is only a bit more dangerous than gasoline, for values of bit.

The above, while true, is meant to humorously illustrate how you can mislead with numbers.

 

[Derswede]

One is all it normally takes....! Of course, you could be like the Subaru driver the other day that left the nozzle in her car and drove off.......! Cashier hit the "Emergency Stop" button in time to prevent a fire......happened at a small airport in NC a couple of years ago, fuel kid was running between 3 airplanes, an impatient pilot fired up and pulled off with the nozzle still in the wing tank filler. Tore up the plane! No fire, thank goodness.

I was based right beside what we call the "Tank Farm" in Greensboro, NC. If you are on final to GSO and landing on 32, look down. The tank farm is under you. No one has dropped a bird into the tank farm yet. I used to work right across the street. One day, they had raised the floating covers on a couple of the tanks, a thunderstorm rolled thru and one well placed lightning strike blew up a tank. Fortunately, it was on a Sunday morning...couple of Baptist churches had sermons about hell that day, it was said. Lost half the windows in my office. Glad I was not working that Sunday!!

Part of my old job was to blow up gas pumps, so that I could be the one to present
safety data to the different Weights and Measures groups we worked with around the world. That was a bit of fun.

Derswede

 

[Dana]

Hydrogen won’t be a competitive fuel unless there are major advances in storage tank materials, and there’s nothing like that on the horizon. People need to remember that hydrogen is NOT an energy source, there are no hydrogen wells; it’s simply an energy storage and transport method. There are several problems with using it as a fuel.

Although its mass energy density is considerably better than gasoline or diesel, its volumetric energy density is several times worse, and that’s as compressed gas. The weight of the required large pressure tank will most likely more than offset the lower weight of the fuel. Additionally, because it’s such a small molecule it’s hard to contain it; seals that can adequately hold other heavier gases leak an unacceptable amount when used with hydrogen.

 

[challenger_II]

As Benjamin Disreali famously said: "There are three kinds of lies: Lies, **** Lies, and Statistics."

The above, while true, is meant to humorously illustrate how you can mislead with numbers.

 

[jedi]

The best way to store Hydrogen as a fuel is to combine it with carbon and liquify or liquefy it. That is what nature has done for us.

As verbs the difference between liquify and liquefy is that liquify is to make liquid while liquefy is (physics|chemistry) to make into a liquid, either by condensing a gas or by melting a solid.

 

[blane.c]

Hydro carbon is not intuitive. I mean if you want to use hydrogen to help minimize the carbon footprint combining hydrogen with carbon seems counter intuitive?

 

[Pilot-34]

Isn’t this thread drift ? How is talking about hydrogen related to thread drift ?

 

[blane.c]

Why battery-powered aircraft will never have significant range

Post #2,114 and post #2,120

 

[jedi]

Isn’t this thread drift ? How is talking about hydrogen related to thread drift ?

This Thread is here to allow a Segway from dedicated posts to allow the originating post to stay on topic.
If there is a reasonable following to this thread the intent is to then start a dedicated thread for that subject.
I am starting a new thread for hydrogen generation use and storage.

 

[Marc Zeitlin]

As Benjamin Disreali famously said: "There are three kinds of lies: Lies, **** Lies, and Statistics."

Not Disraeli (note the spelling) - see:

Lies, damned lies, and statistics - Wikipedia

en.wikipedia.org

for the full derivation. Unknown original author.

 

[Marc Zeitlin]

This Thread is here to allow a Segway from dedicated posts to allow the originating post to stay on topic...

I always wanted a Segway, which was a two wheeled gyroscopically controlled solution looking for a problem. What you're describing is a "segue".

 

[BJC]

I always wanted a Segway, which was a two wheeled gyroscopically controlled solution looking for a problem. What you're describing is a "segue".

Speaking of gyroscopically controlled aircraft maneuvers, the inverted flat spin is my favorite.


BJC

 

[TFF]

Remember that the Segway was designed by a helicopter guy. It was not going to be conventional.

 

[blane.c]

Speaking of gyroscopically controlled aircraft maneuvers, the inverted flat spin is my favorite.


BJC

When you are done, full power, roll inverted, aft stick until vertical.

 

[reo12]

Sorrell Guppy, which I'm prepping to construct, has a range of 150 miles on 5 Gal with half Gal in reserve, speed of 60 to 70. Typical build with Cushman OMC does not climb well and weighs in at 330#. A true ultralight would need 1.5 Gal hr cruise for that kind of range, and of course there is the top speed cap.

That Guppy flies decent with a 277. I've known of a few with a 277

 

[cheapracer]

I was involved with an ELF project in Argentina for CNG (compressed natural gas )
fuel for cars. The main feed was your normal gas main. At the station, there was a compressor to allow a steady flow of gas at rated volumes (do not remember that number).

ALL taxis and buses are CNG in China, always have been in my time here, most lighter commercial vehicles are as well rather than diesel, cause it's so darn cheap. We are talking tens of millions of vehicles. There's a CNG station for every 2 gasoline stations here.

Australia has been big on LPG for the last 50 years, all taxis and Ford even mass produced an LPG Falcon.

Speaking of Falcons, they make good pets. They are responsive, friendly, loyal, and will get rid of mice and other rodents around your home.

In addition to a constant supply of fresh, clean water, in a container suitable for drinking and bathing, you must provide your bird with a daily source of meat. Preferably your bird should fed raw meat from the same kind of animal he would catch in the wild.

 

[jedi]

ALL taxis and buses are CNG in China, always have been in my time here, most lighter commercial vehicles are as well rather than diesel, cause it's so darn cheap. We are talking tens of millions of vehicles. There's a CNG station for every 2 gasoline stations here.

Australia has been big on LPG for the last 50 years, all taxis and Ford even mass produced an LPG Falcon.

Speaking of Falcons, they make good pets. They are responsive, friendly, loyal, and will get rid of mice and other rodents around your home.

In addition to a constant supply of fresh, clean water, in a container suitable for drinking and bathing, you must provide your bird with a daily source of meat. Preferably your bird should fed raw meat from the same kind of animal he would catch in the wild.

View attachment 115739

Speaking of thread drift and eagles and owls:

Would planes be better if they were more like birds?

Eagle-inspired engineering

stories.rvc.ac.uk

Would planes be better if they were more like birds? Eagle-inspired engineering

 

[jedi]

Allert: New thread started as a result of the dreaded Thread Drift in Hydrogen Use Storage and Transport
at post # 85.
See new post "40 + MPG Air and Auto Vehicles"

I often picture how well my 40 mpg Honda Del Sol would fit under the 18 wheelers that I draft on occasion. In reality doing 75+ next to four of the xxx tires and wheels, parts of which are constantly displayed along the once upon a time freeway is a bigger concern.

 

[TFF]

My 71 Triumph Spitfire got 40+ on the highway. It would fit under some semi trailers. Almost did it once to avoid someone trying to hit me head on. I have see the tractor side run over a Lincoln Continental and a pickup, they would have never noticed my Spit under a wheel.