water/alcohol injection

[Laura & Neil]

> | OK, here are my references on water injection:
> IThere is some really nice water injection data in A. R. Rogowski's
> | textbook "Elements of Internal Combustion Engines", McGraw-Hill, 1953,
> | ISBN 07-053575-2, pages 106-109 (unfortunately out of print last time I
> | checked).  He shows 50% improvement in detonation-limited IMEP (basically
> | torque) at stoichiometry, and 28% under more typical fuel-rich conditions,
> | using water flow at 50% of fuel flow.  He showed that you get about 2/3 of
> | the benefit using water flow at 25% of fuel flow.  It's not clear from the
> | text, but I think these benefits were from increasing boost.  The data is
> | referenced from Rowe and Ladd, Journal of the SAE volume 54, no. 1, Jan.
> | 1946, which is more widely available than the textbook.
> |
> | SAE paper 690018 "Inlet manifold water injection for control of nitrogen
> | oxides - theory and experiment", by Nicholls, El-Messiri, and Newhall,
> | 1969.  Mostly part throttle, but does show 12% benefit in max torque with
> | water flow at 50% of fuel flow (naturally aspirated).  [Oops, that was
> | model results, actual data showed much less benefit.]
> |
> | A good history and practical tips are available in "Turbochargers" by Hugh
> | MacInnes, HPBooks (a division of Price Stern Sloan Inc.), 1984.
> |
> | Sir Harry Ricardo did extensive experiments with water injection in the
> | 1920's, which are described in his textbook "The High-Speed Internal
> | Combustion Engine", 1958, pages 36-40.  He concluded that water injection
> | enabled a compression ratio increase from 4:1 to 5:1 with very low octane
> | fuel, for about 10% fuel economy improvement.
> |
> | Water injection is rather briefly described in the classic textbook by
> | Charles F. Taylor "The Internal-Combustion Engine in Theory and Practice"
> | (1968, 1985) Volume 2, page 70.  He recommends water flow at 50% of fuel
> | flow.
> |
> | There is quite a literature on water injection for piston aircraft engines
> | from the 1940's, but they are not widely available.  Some examples are
> | Rothrock et al., "The induction of water to the inlet air as a means of
> | internal cooling in aircraft-engine cylinders", NACA TR 756, 1943; and
> | Bellman and Evvard "Knock-limited performance of several internal
> | coolants", NACA TR 812 (ARR), 1945.  Note that NACA was the precursor to
> | NASA.
>

My Father was a radio operator for the Royal Air Force bomber command during WWII.
He told me that to get fully loaded Lancaster bombers off the ground from some of
the small grass airstrips, they sent the engines throught the gate (overode the
max rev limiter) and injected a mixture of water and methanol. He knows nothing
about the science behind this, all he knew was it gave a tremendous power boost.
Anyone on the list ever heard of this?

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