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Old 23rd April 2006 | 08:26
  #20 (permalink)  
Graviman
 
Joined: Nov 2004
Posts: 1,334
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From: Cambridgeshire, UK
Originally Posted by Dave Jackson
Paul McCready's work is one farsighted step on the road toward electric propulsion.
Dave, could you put a link to this stuff?

Originally Posted by HUDAT
Anybody understand the issues with hydrogen?
It just doesn't work, Hudat, despite having attained a "trendy" image. Hydrogen has the best energy/mass, but the worst energy/volume. To improve energy/volume you use pressurised containment or carbon entrapment, this then gives it the worst energy/mass.

Liquid hydrocarbons are good precisely because they are liquid, and easily transported/pumped. I am not just saying that because of my background in powertrain design analysis. Hydrogen doesn't lubricate mechanical components the way for example diesel or kerosine does, which leads to very high wear rates.

From the thermodynamic view the turbo-diesel engine will always outperform other ICs since you can inject fuel during combustion. I think of TDI as more a reciprocating turbine combustion chamber, which indicates its future potential in helicopters. At this moment diesels are beginning to show their performance, and don't be suprised if a diesel wins LeMans this year:

Ricardo modified JCB 444 Diesel and Audi R10 TDI LeMans Series Racer

HC fuel cells will come, but they will not be competitive to the IC for quite some time. In the interim i would be far happier if (for example) the US implemented a Tier 4 emission diesel car initiative - my VW regularly gets 50mpg...

Mart

Last edited by Graviman; 23rd April 2006 at 17:30.
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