Improved Means for Temporarily Increasing the Power of Combustion Motors.
Year: 1899

page_text: Date of Application, 23rd June, 1899-Accepted, 11th Nov., 1899
COMPLETE SPECIFICATION.
Improved Means for Temporarily Increasing the Power of Combustion
Motors.
I, EUGÈNE COURVOISIER, of Bienne, Canton de Berne, in the Republic of
Switzerland, Manufacturer, do hereby declare the nature of this invention and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement:-
It is well known that in order to produce the motive power in the cylinders
of combustion motors, fuel is admitted on one side, and on the other side atmos-
pheric air used as an oxidising gas for the fuel is admitted and the mixture
ignited. For a given size of motor it is possible indeed to regulate the work
of the engine from zero up to a certain maximum amount, by introducing for
the same quantity of air a larger or smaller quantity of fuel into the cylinder;
but by so doing the maximum fuel supply and in consequence also the
maximum work of the motor is limited by the capacity of the cylinder, while
the quantity of air that can be taken up is only able to effect the combustion
of a determinate quantity of fuel; when a greater amount of fuel is introduced
into the cylinder the surplus is not burnt out and passes through the engine
without giving any working effect.
Combustion motors especially those used for the propulsion of vehicles are
on occasion required to exert greater power than usual and instead of construct-
ing combustion motors with the dimensions required to produce the power
greater than is required under ordinary conditions, it would be better to give
the motor the proper dimensions necessary for the average requirement, while
by so doing the weight of motor would be kept as small as possible a very material
consideration in vehicle motors.
The present invention has for its object to provide means for increasing tempor-
arily the power of the motor so that it is no longer necessary in constructing
combustion motors to consider the greatest power they will be called upon to
exert; they can be built according to their average working power.
It is well known that 23'56% only of the quantity of air introduced into the
motor cylinder is at best active during the combustion; the other 7644% is
azotic gas and remains as an inert body amongst this quantity of air. If a mix-
ture of atmospheric air and pure oxygen or say an oxidising body richer in
oxygen than the atmospheric air is let into the cylinder instead of a given quan-
tity of atmospheric air, it is possible to add a greater weight of fuel to obtain
combustion while more than 2356 parts of the oxidising mixture will be acting
during the combustion. By increasing the amount of oxygen in the oxidising
mixture the power of the motor can also be increased within certain limits above
the maximum power which could be obtained by only using atmospheric air as
an oxidising body for the same motor.
The accompanying drawing is a theoretical indicator diagram of the thermic
cycle of a combustion motor drawn for 1 kilogramme fuel mixture in which the
oxidising agent is supposed to consist of pure atmospheric air only. The com-
bustible mixture is drawn in at a temperature of 20 degrees C. and under atmos-
pheric pressure and hereafter compressed adiabatically up to 21 atm.; under

page_text: this pressure the temperature reaches 193 degrees: it is now artificially ignited;
the pressure increases to 120 atm. and the temperature reaches 1777 degrees;
the fuel used is hereby supposed to require 20 kilogrammes air to effect the com-
bustion of 1 kilogramme fuel, with a heating power of 6000 calories per kilo-
gramme. The lighted mixture expands adiabatically according to the line 2-3
and the surface 0-1-2-3-0 represents the work obtained, which is at the same
time the greatest possible work of which the motor is capable when air alone
is used. If we now use the same motor and introduce, instead of air, an oxidising
mixture containing 47 12% of oxygen (instead of 2356) 1 kilogramme of the
mixture can effect combustion of 1/10 kilogramme fuel against 1 .e. the heat
supply resulting from the combustion is greater; the temperature of combustion
would rise to 3284 degrees C. and the pressure would reach 208 atm. The tem-
perature of combustion will hardly exceed 2000 degrees C. as upwards of 2000
degrees C. the particles of the combustion mixture will not chemically combine;
the fuel introduced into tlie cylinder will merely burn out till the temperature
of dissociation reaches 2000 degrees C. the corresponding pressure is 133 atm.
The fuel on hand can only enter into combination in the same proportion as
the heat produced by the fuel particles is neutralised by the cooling resulting
from the expansion, i.e. at point 2 of the diagram the isothermical expansion
begins and the expansion curve 21-31 is higher than the adiabatic 2-3; the
indicated work is now given by the surface 0-1-21-31-0 which is 22% greater
than the other 0-1-2-3-0.
If the oxydising mixture contains 2018% of oxygen it is possible to have in
one kilogramme of this mixture 1/8 kilogramme fuel for combustion; the tem-
perature of combustion would reach 2000 degrees C. the combustion would still
be effected under constant volume and the expansion go towards the adia-
batic 2-3. The temperature at the end of the expansion would then be 1557
degrees only; the indicated work would be given by the surface 0-1-21-311-0.
According to the kind of fuel utilized it is evident that an halogen (chlorine,
bromine, etc.) could be mixed with air in place of oxygen.
The oxidising mixture can be stored up under pressure into tanks specially
constructed for that purpose and fitted with a pipe communicating with the
combustion cylinder; by means of an admission valve set to work by the motor,
the oxidising mixture is admitted in the same way as the fuel, at the right
moment, i.e. during the suction period of the piston, whilst the use of a stop
valve moved by hand or by the regulator serves to regulate the quantity of
oxydising mixture to be admitted from time to time.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is.
An improved means for temporarily increasing the power of combustion
motors, consisting in introducing to the fuel contained in the combustion cylinder,
instead of atmospheric air, an oxydising mixture richer in oxydising gas (oxygen
or halogen).
Dated this 2nd day of June 1800
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.