Posted on 06/16/2008 10:01:03 AM PDT by Red Badger
Considering the cost of oil at near 140, wouldn’t it make sense to let crops die and just let weeds grow, then when they die make this biodiesel? I’m just concerned that good intentions often lead to disaster.
Oh, MPG. I thought it said 60 MPH Hummer, and, well, never mind...
man you really didnt read the article. he is injecting hydrogen into it. I am sure has done other modifications other than just dropping a duramax in a H2. The only think I dont get, he is pretty smart fellow , why did he bother to make a special harness and use the factory comp for the conversion, he can get get a microsquirt for 400 dollars and do engine management.
on cnn he said the converison was 35k. I dont know what he is converting for 5k, maybe that is the price of the turbine, once you factor in the electric motor batteries and control system the price will get up there. My wife had my project car towed off, I hadnt started on it yet but I wasa saving it for an electric conversion.
Andy Granatellis’ technology was proven beyond a doubt at Indy that’s why they changed the rules so that the others would not have to compete against him.
Here is a serious problem with the Carbon Dioxide fixation the golbal warming alarmists have. Burn Hydrogen and you get water vapor, which is a far more efficient greenhouse gas than Carbon Dioxide. Not only will it not "end greenhouse gasses", but burning hydrogen will enhance them.
There is no mention of hydrogen being injected into the H2 that supposedly wowed the GM engineers two years prior to the article being written. It was just an H2 with a Duramax diesel bolted in, with a valve to switch to veggie oil after it warmed up. Conventional, and old tech. No reason for the GM engineers to faint over it.
Hydrogen injection is mentioned for the turbine powered H3, but that is nowhere to be seen yet.
Hydrogen injection is mentioned for the H1 that supposedly fell apart on him, but the claims are dubious. The hydrogen tank lasting 700 miles would mean it was a giant tank, or he wasn’t using enough to do anything.
Hydrogen injection is unlikely to do what he claims, anyway, unless you use a lot of hydrogen.
I think you haven’t read the article very carefully.
bump
“Putting a diesel engine in the Hummer, however, required Goodwin to crack GM’s antitheft system, which makes it a pain to swap out the engine. In that system, the engine communicates electronically with the body, fuel supply, and ignition; if you don’t have all the original components, the car won’t start. Goodwin jerry-rigged a set of cables to trick the engine into believing the starter system had broken, sending it into “fail-safe mode”—a backdoor mechanism installed at the factory. (At one point in his story, Goodwin wanders over to a battered cardboard box in the corner of the garage and hauls out an octopuslike tangle of wires—”the MacGyver,” his hacking device. “I could have sold this for a lot of money on eBay,” he chuckles.)
Once he’d picked the car’s lock, Goodwin installed the Duramax and a five-speed Allison—the required transmission for a Duramax, which also helps give it race-car-like control and a rapid take off. After five days’ worth of work, the Hummer was getting about 18 mpg—double the factory 9 mpg—and twice the original horsepower. He drove it over to a local restaurant and mooched some discarded oil from its deep fryer, strained the oil through a pair of jeans, and poured it into the engine. It ran perfectly.”
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This makes no sense whatsoever. Why not just buy a new Chevy HD pickup, which already has the Duramax and the Allison? Why go to all the trouble, hassle, and major expense with modifying the 15 year old H1 Hummer? Just double the mileage and power of the Chevy pickup, which already has what you want in it.
I understand the challenge with the old H1, but if he wants to show the world that he can double the mileage and increase the horsepower of a diesel, it makes much more sense to use the Chevy pickup. It’s already ready for his mods, and lots more people own them.
Gas turbine component costs are not really about precision components. You can buy a $5 roller ballbearing with the OD cylindricity within a couple ten-thousandths of an inch.
Gas turbine components need specialized materials developed for high-temperature applications. That means high-nickel super alloys, if you want the engine to last for more than a couple of starts.
If you think gas prices have escalated sharply, you'll really get your feelings hurt when you go to buy some nickel.
Maybe it’s just a limitation of my understanding of the laws of thermodynamics and such, but I fail to see how adding a little hydrogen gas to the mix can improve diesel engine fuel economy that much.
I own a tool and die business, your talking to someone who has to pick himself off the floor every time I order cobalt or chrome moly based steel and get the bill.
Try combining that claim with the energy density of hydrogen at the pressures found during the intake stroke.
No way it contains the same energy as the displaced diesel.
You have my condolences on cobalt and chromoly prices, sir.
I found this online:
http://home.weblung.org/meyer/hydroge2.htm
“Direct high pressure hydrogen injection is the most efficient application in internal combustion engines. Injection is provided after the closing of the valves. Ignition is done with a spark or glow plug. Preignition is decreased by using this application. Since hydrogen does not displace air in the cylinder, it provides better volumetric efficiency which means higher power.”
Hydrogen has an energy density of 143 MJ/kg at STP, and compression causes it increase. Diesel has an energy density of 45.8 MJ/kg, and compression only effects burn rate, not energy density.
So, the answer to your question is: No, hydrogen does not have the same energy density as diesel. It is much higher.
So you either have much less energy in the same volume, or so much pressure there is no way to intake air for combustion.
Good point, I have to concede that one. I did not consider volume. However, The storage cylinders for compressed hydrogen are usually kept at about 70 Mpa (700 bars). I don’t kmnow if that is enough to make up for the density issue or not, but that is some serious compression. Also, the article said the tank contained supercompressed hydrogen. If 70 MPa is the norm, what is considered supercompressed? I couldn’t find an answer to that, do you know?
That only reduces the storage volume. Without that you would need to drive a blimp.
At that density in the storage tank, it can be close to the same energy density per unit volume of diesel, but you cannot have intake cycle of the engine operating at 10,000 psi or you will not be able to take in any air for combustion.
Well then...sounds like the dude is full of schnit. Going by the article, it sounds good, though. Then again, I did make a B in physics. 60 mpg would be nice at $4.00 a gallon, though.
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