GB2070684A - Supply steam to IC engines - Google Patents

Abstract

Steam generated in a copper tube coil or in a tank in or on the engine exhaust manifold is supplied to the intake manifold through a flexible pipe containing a jet. Water is supplied to the generator from a reservoir via an adjustable float chamber.

Description

SPECIFICATION Device for reducing petrol censurnption The present invention relates to a device for reducing the consumption of petrolem fuels by internal combustion engines. The petroleum fuels to which the invention is applicable include both petrol and diesel, these being the fuels most commonly employed at the present time.

There is currently a clear limit on the world's reserves of petroleum fuel and, in recent years, this, coupled with increasing price and political instability in many of the major producing areas, has led to an increasing desire to reduce consumption of such fuels. It has long been known that fuel consumption in the internal combustion. engine can be substantially reduced by feeding the fuel in admixture with water to the internal combustion engine. What is more, it is well known that admixture of a proportion of water with petroleum fuel substantially reduces environmental pollution, another major concern at the present time. However, despite the known advantages of the concomitant use of water with petroleum fuels, it has not been so used in practice.

To date, most proposals for the use of water with petroleum fuels have concentrated on preparing a preliminary mixture of water with the fuel, e.g. by forming an emulsion, which has necessitated the provision of a suitable emulsifier. Many attempts have been made to find a suitable emulsifier and an enormous valiety of chemicals have been proposed for this use. Most of these proposals have come to nothing for one or more of the following reasons: even the best emulsions have a limited stability; the emulsifiers themselves have an adverse effect on the material of the engine, burning efficiency etc. or cause pollution; the emulsifiers themselves and/or the preparation of the emulsion are expensive; the energy required to produce the esnul- sion exceeds the energy equivalent of the fuel saved.

We have now discovered a method of overcoming the disadvantages of previous systems in which water is introduced, with the fuel, into the cylinder of an internal combustion engine whilst maintaining and, indeed, in preferred embodiments adding to the known advantages.

Thus, in its broadest aspect, the present invention consists in an internal combustion engine provided with: a container for holding water; a heat exchanger arranged to receive heat from hot exhaust gases from said engine and thereby to heat said water; and means for feeding heated water from said heat exchanger to a combustion chamber of said engine.

The invention further consists in a method of operating an internal combustion engine in which, during operation, water is heated by hot exhaust gases from said engine and the heated water is drawn by suction generated in the combustion chamber of said engine into said combustion chamber.

Under normal operating conditions, the temperature of the exhaust gases will be sufficient to convert the water in the heat exchanger to steam and thus the heated water fed into the combustion chamber of the internal combustion engine will be in the form of steam. In the event that adequate heat is not supplied by the exhaust gases to convert the water to steam, nonetheless heated vaporized water will still be drawn into the combustion chamber and it will still be possible to obtain the beneficial effects of the present invention, although, in this case, it may be difficult to supply sufficient water to optimise these beneficial effects.

However, under preferred conditions of operation, liquid water as such is at no time introduced into the engine, the water being wholly introduced as steam.

Starting up the vehicle is carried out exactly as with a conventional engine and the engine runs on ordinary fuel. It is only after the vehicle has started and the exhaust system (especially the exhaust manifold) has heated up that steam is generated and fed to the engine, although this happens quickly after start-up. lihereaRer steam is generated continuously, although it is a feature of the invention that, because the amount of steam generated is determined by the heat of the exhaust, the amount tends to follow engine requirements, i.e. acceleration.

Steam adds BHP and reduces pollution considerably. A water tank smaller than the petrol tank (e.g. about one-third the volume) will normally supply sufficient water; if, however, for any reason the water runs out, the vehicle automatically reverts to normal running on, e.g., petroi or diesel alone.

In a standard, petrnl4ueled internal combustion engine, rather than feeding the heated water directly into the cylinders of the engine, the water is preferably introduced into the inlet manifold via a small jet (to reduce vac- uum) attached to the manifold. The water is preferably fed via the induction but may also be fed via the carburettor. In other forms of internal combustion engine, similar arrangements may be made.

A variety of different heat exchanger arrangements can be adopted, depending upon the precise design of the internal combustion engine and of the vehicle or other system powered by the engine. For example, in one embodiment of the invention, a container for the water may be affixed to the exhaust system (preferably the exhaust manifold) of the internal combustion engine, so that the water is in good thermal contact with the exhaust system. In this case, the water in the container is directly heated, rises in the container and is emitted via a pipe leading to the combustion chamber of the engine. In this embodiment, there is preferably also provided a reservoir for storing water, connected to the container via an adjustable flow chamber, to maintain a predetermined water level in the container.

In an alternative embodiment, water is fed from a container through a pipe in thermal contact with the exhaust system and is heated whilst passing through the pipe and then the heated water (preferably in the form of steam) is fed to the combustion chamber of the engine. Again, this embodiment is preferably provided with a reservoir for holding water and feeding the water via an adjustable float chamber to said pipe. The pipe may be coiled around the outside of the exhaust system, but better results are achieved if the pipe is fed into and coiled in the exhaust system, preferably the exhaust manifold. The pipe is preferably so arranged that water within the pipe and exhaust gases within the exhaust system flow in countercurrent to miximise heat exchange.

For best heat conductivity, the pipe is preferably made of copper.

The invention is further iillustrated by the accompanying drawings, in which: Figure 1 illustrates schematically a preferred heat exchange arrangement for use in the present invention; and Figure 2 illustrates an alternative embodiment of heat exchange arrangement for use in the present invention.

Referring first to Fig. 1, a length of copper tube 1 is coiled within exhaust manifold 2.

The diameter of the copper tube 1 is so chosen as to balance the conflicting requirements of maximising heat exchange between the water within the copper tube and the exhaust gases within the exhaust manifold and maximising fow of water through the copper tube; a suitable tube is of 0.25 inch outer diameter. Water level in the tube is controlled by a float chamber 3, water being supplied to the float chamber 3 via a tube 4 from a reservoir (not shown). After the internal combustion engine (not shown) has been operating for some time, the exhaust gases passing through exhaust manifold 2 become sufficiently hot to-convert water in the copper pipe 1 to steam. The steam passes along copper tube 1, and thence, via a flexible pipe 5, to the inlet manifold of the internal combustion engine.If desired, the portion of the copper tube 1 outside the exhaust manifold 2 may be partially housed within the housing 6, which may be, for example, a 1.5 inch outer diameter steei tube, thus providing further heat exchange contact between the exhaust gases and the water in the copper tube. The flexible pipe 5 is preferably fined with a small jet to reduce vacuum and preferably also incorporates a water deflector to reduce introducing of liquid water into the internal combustion engine.

Ports 7 are exhaust ports, supplying the exhaust gases from the cylinder heads of the internal combustion engine. The exhaust gases are ejected via exhaust pipe 8 in the usual way. However, as is well known, the introduction of water into the cylinders of the internal combustion engine (in the case of the present invention, this water is introduced in the form of steam) reduces petrol consumption and substantially reduces the. output of toxic gases in the exhaust.

In the alternative embodiment illustrated in Fig. 2, the water is brought into heat exchange contact with the exhaust gases by means of a tank 11 braised to the exhaust manifold. Otherwise, the parts illustrated and their operation are substantially the same as in the embodiment illustrated in Fig. 1. Again, the water is supplied to the tank 11 from a float chamber 3 and steam escapes through a flexible pipe 5 fitted with a jet 1 2.

Claims (7)

1. An internal combustion engine provided with: a container for holding water; a heat exchanger arranged to receive heat from hot exhaust gases from said engine and thereby to heat said water; and means for feeding heated water from said heat exchanger to a combustion chamber of said engine.

2. An internal combustion engine according to claim 1, in which said heat exchanger comprises a coil of copper pipe such that, when the engine is in operation, the copper pipe is in heat exchange contact with said hot exhaust gases.

3. An internal combustion engine according to claim 2, in which said copper pipe is coiled within the exhaust system of the engine.

4. An internal combustion engine according to claim 1, in which said heat exchanger comprises a tank in heat exchange contact with the exhaust system of the internal combustion engine.

5. An internal combustion engine according to claim 1, provided with a heat exchange arrangement substantially as hereinbefore described with reference to, and as shown in, Fig. 1 or Fig. 2.

6. A method of operating an internal combustion engine in which, during operation, water is heated by hot exhaust gases from said engine and the heated water is drawn by suction generated in the combustion chamber of said engine into said combustion chamber.

7. A method according to claim 6, sub stantially as hereinbefore described with reference to Fig. 1 or Fig. 2.