View Single Post
Old 06-11-2008, 05:33 AM   #6 (permalink)
EcoModding Apprentice
Join Date: Jun 2008
Location: Waikele, Hawaii
Posts: 108

88CRX - '88 Honda CRX Standard DX
90 day: 32.74 mpg (US)

IS250 - '07 Lexus IS250
90 day: 25.79 mpg (US)

RX300 - '00 Lexus RX300
90 day: 18.38 mpg (US)
Thanks: 0
Thanked 5 Times in 5 Posts
Okay i'm at home wondering about this, i found an articale in wikipedia:

There might be merit to HHO, but not as the way they advertise... 50% is probably based on higher concentrations of Hydrogen, than what HHO generators can produce. But that small about might still give an improvement.

This part got my attention:

Automotive fuel enhancement systems work by injecting a hydrogen rich mixture, or pure hydrogen into the intake manifold of an internal combustion engine combined with air/fuel ratio, and timing modification. A small amount of hydrogen added to the intake air-fuel charge permits the engine to operate with leaner air-to-fuel mixture than otherwise possible.[3] As the air/fuel mix approaches 30:1 the temperature of combustion substantially decreases effectively mitigating NOx production.[3]

Under idle conditions power is only required for extraneous components other than the drive train, therefore fuel consumption can be minimized. A 50% reduction in gasoline consumption, at idle, was reported by numerically analyzing "the effect of hydrogen enriched gasoline on the performance, emissions and fuel consumption of a small spark-ignition engine".[4]

Under most loads near stoichiometric air/fuel mixtures are still required for normal acceleration, although under idle conditions, reduced loads, and moderate acceleration Hydrogen "addition" in combination with lean burn engine conditions "can guarantee a regular running" of the engine "with many advantages in terms of emissions levels and fuel consumption".[5]

Increases "in engine efficiency are more dominant than the energy loss incurred in generating hydrogen".[3] This is specifically with regard to use of a hydrogen reformer. Overall computational analysis "has marked the possibility of operating with high air overabundance (lean or ultra-lean mixtures) without a" substantial "performance decrease, but with great advantages on pollution emissions and fuel consumption".[4]

Overall comparing "the properties of hydrogen and gasoline, it is possible to underline the possibilities, for hydrogen fueled engines, of operating with very lean (or ultra-lean) mixtures,[6] obtaining interesting fuel economy and emissions reductions".[5] The "concept of hydrogen enriched gasoline, as a fuel for internal combustion engines, has a greater interest than pure hydrogen powered engines because it involves fewer modifications to the engines and their fueling systems".[5]

[edit] Engine Control

ECU or carburetor modifications are required to establish lean or ultra lean burn engine conditions; where the hydrogen permits leaner conditions than possible with solely hydrocarbon fuel.[7][3]
  Reply With Quote
The Following User Says Thank You to 88CRX For This Useful Post:
rvind2008 (05-23-2011)