GB2196384A

GB2196384A - Diesel and steam engine

Info

Publication number: GB2196384A
Application number: GB08624796A
Authority: GB
Inventors: James Black
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-10-16
Filing date: 1986-10-16
Publication date: 1988-04-27
Also published as: GB8624796D0

Abstract

In the side wall of the or each cylinder 1 there is an air inlet port 4 covered and uncovered by the piston 2 at every two strokes. In the cylinder head there is a diesel fuel injector 6, a water injector 7, a burnt gas exhaust valve 8 and a steam exhaust valve 9. The injectors 6, 7 and exhaust valves 8, 9 are opened and closed in phased relation with each other to provide alternate combustion and steam cycles. The water pumped to the injector 7 is heated in an exchanger by exhaust gases. <IMAGE>

Description

SPECIFICATION Combined diesel and steam engine assembly This invention relates to a combined diesel and steam engine assembly Previous systems for using waste heat to produce steam power have first heated water through the wall of an internal combustion engine cylinder and then evaporated it with exhaust heat. A disadvantage of such systems is the large temperature drops resulting in large losses of power available from the steam. An object of the invention is to obviate or mitigate the above disadvantage.

Some diesel engines are of the uniflow twostroke type which have inlet ports in the cylinder and exhaust ports in the head. It is proposed to modify such an engine so that it can be used in a combined diesel and steam engine.

Accordingly, the present invention provides a combined diesel and steam engine assembly comprising a reciprocating piston compression-ignition internal combustion engine having in the side wall of the or each cylinder an air inlet port to be covered and uncovered by the piston at every two strokes thereof and in the cylinder head a diesel fuel injector, a water injector, a burnt gas exhaust valve and a steam exhaust valve, means for opening and closing the injectors and exhaust valves in phased relation with each other and with the air inlet port but at every four strokes of the piston, an air compressor connected to the air inlet port, a diesel fuel injection pump connected to the diesel fuel injector, a water pump connected to the water injector, and a heat exchanger having one part connected to the burnt gas exhaust valve and the other part interconnected between the water pump and the water injector.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure l is a partial sectional view of a diesel and steam engine assembly; and Figure 2 is a timing diagram.

In the drawing, a combined diesel and steam engine assembly comprises a reciprocating piston compression-ignition internal combustion engine. The engine as such compreses a cylinder 1, a piston 2 reciprocable in the cylinder 1, and a connecting rod 3. In the side wall of the cylinder 1 is an air inlet port 4 to be covered and uncovered by the piston 2. An air compressor 5 is connected to the air inlet port 4. In the head of the cylinder 1 are a diesel fuel injector 6, a water injector 7, a burnt gas exhaust valve 8 and a steam exhaust valve 9.

Respective pumps (not shown) are provided for the injectors 6 and 7. Furthermore, a heat exchanger (not shown) has one part connected to valve 8 and the other part interconnected between the water pump and the injector 7.

In operation and with reference also to Fig.

2 wherein the hatched areas indicate the phases when the port 4, the injectors 6 and 7 and the valves 8 and 9 are open. Referring to the dead centre positions of the piston 2 and the crank angle and starting at B.D.C. (0 ) the situation is such that the first stroke commences with compressed air being admitted through the port 4, steam exhaust being concluded shortly before the port 4 is fully closed. Thereafter the charge of air is compressed within the cylinder 1. As the first stroke ends and the second stroke at T.D.C.

(180 C) diesel fuel is injected into the charge of compressed air and compression ignition takes place. Operation continues with explosive expansion of the fuel and air mixture.

Thereafter the valve 8 is opened to be followed by the port 4 being uncovered so that at B.D.C. (360 ) burnt gas is being exhausted and being scavenged by air. The valve 8 remains open until shortly before the end of the third stroke to provide heat, via the heat exchanger for water being injected around T.D.C. (540 ). The water is converted into steam which expands during most of the fourth stroke. Thereafter the valve 9 is opened to be followed by the port 4 being uncovered so that at B.D.C. (720 ) the steam is being exhausted and being scavenged by air.

It will be noted that in operating the engine assembly that every second stroke is a power stroke but that every fourth stroke does not require fuel since the power in that stroke is provided by steam. The quantity of water injected could be controlled by the thermostat so that when hot the quantity is much greater than that of fuel. Most of the water for injection could be obtained by condensing the exhaust steam.

1. A combined diesel and steam engine assembly comprising a reciprocating piston compression-ignition internal combustion engine having in the side wall of the or each cylinder an air inlet port to be covered and uncovered by the piston at every two strokes thereof and in the cylinder head a diesel fuel injector, a water injector, a burnt gas exhaust valve and a steam exhaust valve, means for opening and closing the injectors and exhaust valves in phased relation with each other and with the air inlet port but at every four strokes of the piston, an air compressor connected to the air inlet port, a diesel fuel injection pump connected to the diesel fuel injector, a water pump connected to the water injector, and a heat exchanger having one part connected to the burnt gas exhaust valve and the other part interconnected between the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

SPECIFICATION Combined diesel and steam engine assembly This invention relates to a combined diesel and steam engine assembly Previous systems for using waste heat to produce steam power have first heated water through the wall of an internal combustion engine cylinder and then evaporated it with exhaust heat. A disadvantage of such systems is the large temperature drops resulting in large losses of power available from the steam. An object of the invention is to obviate or mitigate the above disadvantage.

Some diesel engines are of the uniflow twostroke type which have inlet ports in the cylinder and exhaust ports in the head. It is proposed to modify such an engine so that it can be used in a combined diesel and steam engine.

Accordingly, the present invention provides a combined diesel and steam engine assembly comprising a reciprocating piston compression-ignition internal combustion engine having in the side wall of the or each cylinder an air inlet port to be covered and uncovered by the piston at every two strokes thereof and in the cylinder head a diesel fuel injector, a water injector, a burnt gas exhaust valve and a steam exhaust valve, means for opening and closing the injectors and exhaust valves in phased relation with each other and with the air inlet port but at every four strokes of the piston, an air compressor connected to the air inlet port, a diesel fuel injection pump connected to the diesel fuel injector, a water pump connected to the water injector, and a heat exchanger having one part connected to the burnt gas exhaust valve and the other part interconnected between the water pump and the water injector.

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawing, in which: Figure l is a partial sectional view of a diesel and steam engine assembly; and Figure 2 is a timing diagram.

In the drawing, a combined diesel and steam engine assembly comprises a reciprocating piston compression-ignition internal combustion engine. The engine as such compreses a cylinder 1, a piston 2 reciprocable in the cylinder 1, and a connecting rod 3. In the side wall of the cylinder 1 is an air inlet port 4 to be covered and uncovered by the piston 2. An air compressor 5 is connected to the air inlet port 4. In the head of the cylinder 1 are a diesel fuel injector 6, a water injector 7, a burnt gas exhaust valve 8 and a steam exhaust valve 9.

Respective pumps (not shown) are provided for the injectors 6 and 7. Furthermore, a heat exchanger (not shown) has one part connected to valve 8 and the other part interconnected between the water pump and the injector 7.

In operation and with reference also to Fig.
2. A combined diesel and steam engine assembly substantially as hereinbefore described with reference to the accompanying drawing.

2 wherein the hatched areas indicate the phases when the port 4, the injectors 6 and 7 and the valves 8 and 9 are open. Referring to the dead centre positions of the piston 2 and the crank angle and starting at B.D.C. (0 ) the situation is such that the first stroke commences with compressed air being admitted through the port 4, steam exhaust being concluded shortly before the port 4 is fully closed. Thereafter the charge of air is compressed within the cylinder 1. As the first stroke ends and the second stroke at T.D.C.

(180 C) diesel fuel is injected into the charge of compressed air and compression ignition takes place. Operation continues with explosive expansion of the fuel and air mixture.

Thereafter the valve 8 is opened to be followed by the port 4 being uncovered so that at B.D.C. (360 ) burnt gas is being exhausted and being scavenged by air. The valve 8 remains open until shortly before the end of the third stroke to provide heat, via the heat exchanger for water being injected around T.D.C. (540 ). The water is converted into steam which expands during most of the fourth stroke. Thereafter the valve 9 is opened to be followed by the port 4 being uncovered so that at B.D.C. (720 ) the steam is being exhausted and being scavenged by air.

It will be noted that in operating the engine assembly that every second stroke is a power stroke but that every fourth stroke does not require fuel since the power in that stroke is provided by steam. The quantity of water injected could be controlled by the thermostat so that when hot the quantity is much greater than that of fuel. Most of the water for injection could be obtained by condensing the exhaust steam.

1. A combined diesel and steam engine assembly comprising a reciprocating piston compression-ignition internal combustion engine having in the side wall of the or each cylinder an air inlet port to be covered and uncovered by the piston at every two strokes thereof and in the cylinder head a diesel fuel injector, a water injector, a burnt gas exhaust valve and a steam exhaust valve, means for opening and closing the injectors and exhaust valves in phased relation with each other and with the air inlet port but at every four strokes of the piston, an air compressor connected to the air inlet port, a diesel fuel injection pump connected to the diesel fuel injector, a water pump connected to the water injector, and a heat exchanger having one part connected to the burnt gas exhaust valve and the other part interconnected between the water pump and the water injector.