Wesley Bruce writes
> These guys are twits. We have known for
decades that hydrogen powered
> cars need ceramic piston heads, valves and liners. And the liners have
> been around for as many years!
> cars need ceramic piston heads, valves and liners. And the liners have
> been around for as many years!
Its even easier than that. It was learned years ago
that the "ceramic" itself does not have to be a separate part, but can
easily be derived from the underlying aluminum in the pistons and cylinders.
Normally aluminum is anodized with a thin oxide coating to prevent further
oxidation in service, but to further prevent hydrogen imbrittlement - all one
needs to do is add a little more magnesium to the die-casting alloy and then
heavily anodize. In all of nature there is no better containment for hydrogen
than MgO or anodized magnesium. It does not suffer embrittlement nor allow
the underlying metal to suffer embrittlement. I agree with Wesley that this web
page must be a front for unscrupulous fund-raisers of some kind, who have little
engineering background.
Anyway this does raise a very interesting issue
about "why" H2 is such a good fuel in the ICE.
Forget expensive fuel cells. Dead-end street (at
least for now) -due to precious metals! If you have hydrogen as a fuel, and
decide to forego its best use (fertilizer) then the easy answer, staring
everyone in the face these days is - just convert the traditional ICE to burn
it.
Why layer on a completely new process (fuel cells)
which are NOT more efficient than the ICE, in practice? Sounds like a
mischievous plot of the petroleum industry to delay the hydrogen economy,
doesn't it?
There are many reason why burning H2 is more
efficient in an ICE than gasoline. Earlier I posted some information about
*steam* being a preferable medium for translating heat to work over CO2. It
turns out that although this is true, steam cannot account for the whole
advantage - but is advantageous to a lesser extent than was indicated. Due to
the overwhelming presence of nitrogen in the exhaust, steam can only raise the
Carnot efficiency at most 8-10 percentage points (that correction thanks to
RvS) and more complete combustion can account for another substantial part of
the answer to the higher efficiency.
However the greater percentage of steam in the
exhaust does in experiments make a more substantial difference in Carnot
eff. due to a third important reason. The complete answer
to why the efficiency of hydrogen is so incredibly high in an ICE must
include "jerk" ! Jerk is a more than an insult these days, if one applies its
meaning to power laws.
Why do I say "incredible" ? hey, in their very
first try, Ford (not a powerhouse of innovation these days) was able to get 45%
Carnot efficiency out of a *small* converted ICE. I think 55% is possible -
which is double the efficiency of gasoline. For Ford to anything like this on a
first attempt must indicates that inertia can be overcome by jerks
;-)
More seriously, the third part of the "much greater
efficiency" equation probably goes back to a subject that we periodically allude
to on vortex - power laws and particularly power laws relating to kinetics. As
Frank Grimer has visualized, you have:
dL/dT ......VELOCITY .......moving scenery out the car window
d2L/dT2 ....ACCELERATION ...being pushed back in ones seat as the plane takes off
d3L/dt3 ....JERK............Mmm..more difficult - being hit over the head with a bottle perhaps?
d4L/dT4 ....JOUNCE..........I have no feeling whatsoever for this or high derivatives.
"But the failure to visualize these higher order derivative is because we are thinking in terms of straight line motion. If I think instead in terms of circular motion, or better still, helical motions, then things become very much easier.
If I allow myself to be pinned to the wall of a fairground centrifuge then I can experience being "pushed back in my seat on a continuous basis. By imposing a circular motion on this circular motion to form an open vortex helix I can visualize the next derivative, though I am well past the age where I would want to experience it - and so on - and so forth."
Anyway - the possibility of some of the hydrogen shock wave being converted
to Jerk or Jounce is a definite possibility here. A free proton, during the
early stages of combustion has what - 46 times more mobility than CO2 - and that
is if there is no power law in effect. The free proton during combustion may be
a key to the higher efficiency, and there are ways to maximize this effect -
ways that the folks at Ford will never figure out on their own.
BTW - why is Ford downplaying this H2 ICE advancement and still pursuing
the fuel cell as a viable option, when their own scientists have admitted the
fuel-cell is "dead-in-the-water" unless it can be made without platinum (it
can't, so far) ?
I don't have time to track down the details, but there is an oily smell to
it.
Jones
