GB2335636A - High pressure hot gas marine engine and propulsive system - Google Patents

Abstract

A Marine Propulsive System utilises a pulse jet engine comprising at least one combustion cylinder 4 supplied separately with compressed air and fuel via manifold 3 and fuel injectors 5 respectively, and fired by a spark plug 7. The cylinder is filled and exhausted via valves 2 and 9 opened or closed as necessary by auxiliary powered camshafts 1 and 8.The exploded fuel air mixture leaves through spring loaded non-return flaps 10 and thereafter enters a gas outlet tube 4 in a rising water lift pipe 1 provided with a forward/reverse flap 5 and non return flaps 9. A water turbine 6 in pipe 1 drives an air compressor for supplying compressed air to the cylinder 4. The water gas mixture is discharged below the water line through a steerable vent.

Description

2335636 High Pressure Hot Gas Marine Engine and Propulsion System z List

of Contents Page i Cover sheet ii List of contents 1 Engine overview 2...

(1. 1) Overview (1.2) Fuel (1.3) Valve springs (1.4) Combustion cylinders (1.5) Engine cooling (1.6) Normal running (1.7) Exhaust shock absorber (1. 8) Exhaust valve design (1.9) Injectors 4... The Propulsion System (2. 1) Overview (2.2) Reversing (2.3) Vent design (2.4) Idling mode (2.5) Engine protection Variations (3. 1) Direct Exhaust (3.2) Conventional engine (3.3) Steam injection 6... Summary

Annexes Annex 1... Fig 1 - The Engine Annex 2... Fig 2 - Propulsion system overview Fig 3 - Alternative propulsion method Annex 3... Fig 4 - Steam injection 3 1.The Engine tfig l.) 1.1. Overview 1. 1. 1. This simplified internal combustion engine has no crankshaft or pistons to compress the air/fuel mixture. An auxiliary engine driven air compressor would provide the necessary compressed air. The auxiliary engine could also be used to drive the main engine camshafts and direct fuel injection systems. It may be possible and more efficient to use an electric motor to undertake these tasks. When the ship is under way, the turbine driven air compressor could satisfy the high pressure air requirements of the main engine, with the auxiliary supply only required for starting.

1.1.2. The charging, firing and running sequence is as follows: The inlet camshaft (1) opens the inlet valve (2). Compressed air in the inlet manifold (3) fills and pressurises the combustion cylinder (4). Direct fuel injectors (5) inject the main fuel into the combustion chamber. A starting fuel injector (6), may be situated in a sparkplug firing tube (small open-ended tube containing the spark plug (7)) to provide adequate quantities of starting fuel (e.g. petrol) during the initial power up process. The spark plug would be electronically initiated.

1.1.3. Immediately on firing, the exhaust camshaft (8) opens the exhaust valve (9). The exploded fuel air mix leaves the cylinder through spring loaded non-return flaps (10) in the firing tube (11) into a pressure direction chamber. The exhaust valve is held open by the exhaust camshaft, the inlet valve is opened and compressed air expels the exhaust fumes. The exhaust valve then closes allowing the cycle to begin again.

1.2. Main Fuel 1.2.1. As the air pressure can be controlled, the fuel range is considerable and subject to testing.

LA.

1.3. Valve Springs 1.3.1. The exhaust valve spring would need to be graded to the air pressure used and shock protected to allow for exhaust camshaft delay. The inlet valve would be tuned to air pressure.

1.4. Combustion Cylinders 1.4.1. The number, size and shape of cylinders would be dependent on the power requirements of the engine. Similarly, there would be a range in the number and size of valves and camshafts used.

1.5. Engine Cooling 1.5.1. Water or compressed air governed by engine dimensions. A proposed method of water-cooling can be found at paragraph 3.3.

1.6. Normal Running 1.6.1. By controlling the fuel injection system, the engine could run on any number of cylinders. Furthermore, power could be controlled by variations in the pressure of the HP air supply and by the amount of fuel injected.

1.6.2. It may be possible to produce additional power by injecting water into the pressure chamber and utilising the resultant steam (See para 3.3) 1.7. Exhaust Shock Absorber 1.7.1. The exhaust valve is initially opened by the combustion pressure in the cylinder, the cam only following. To keep the valve open for the necessary period, the valve requires to be shock protected in order to avoid damage.

1.7.2. This may be done by the use of two coil springs on the valve. The main outer spring would be tensioned to hold the compressed air in the cylinder. The inner coil spring would be of similar length and graduate from light to heavy tension to engage when the valve is near the end of its travel.

1.8. Exhaust Valve Design 1.8.1. Valves would be conical in shape to aid gas flow. A deep valve seating is required to prolong engine life. All valves and camshafts to run oil lubricated, subject to final engine design.

1.8.2. Multi-valves: a large combustion cylinder would need a multiple exhaust inlet valve combination. This would allow greater strength around the valve areas and reduce pressure on 6 the outlet valve. A multiple cam or valve lift assembly would also be necessary.

1.9. Injectors 1.9.1. Any number of injectors in any position may be accommodated.

2.The Propulsion Sy tem 2.1. Overview (See fig 2) 2.1.1. The high-pressure hot gas produced by the engine is forced directly into a rising tube or lift pipe (1) carrying water, creating a 'water lift' effect. The gas and water is then directed overboard through a steerable vent at the stem of the vessel. This vent would be placed below the vessel's unladen waterline.

2.1.2. The displacement of the water through the lift pipe creates a 'sinking ship syndrome' as the intake pipes (7) are situated deeper in the hull and thus in an area of higher outside water pressure.

2.1.3. The inrushing water is made to turn a turbine, which would drive an air compressor (6) and provide the lip air supply to the engine when the ship is under way.

2.2. Reversing the Vessel 2.2.1. A moveable flap (5) at the base of the engine exhaust cylinder may be utilised to divert the gas/water mix back through the intake vents for reversing the ship.

2.3. Vent Design 2.3.1. Both intake and exhaust vents would be steerable to allow the ship to be fully manoeuvrable. A water intake vent would be placed on each side of the hull and would be grill covered to prevent the intake of debris.

2.4. Idling Mode 2.4.1. A pressure release exhaust pipe (8) is provided for running the engine out of drive. This would be controlled by a pressure valve and would vent to atmosphere.

2.5. Engine Protection 2.5.1. Spring loaded non-return flaps (9) are watertight when locked closed and unlocked when the chamber is pressurised. This will prevent the ingestion of water into the engine.

7 3. Variations on a Theme 3.1.Direct Exhaust 3.1.1. A possible alternative to the proposed propulsion system would be for the firing tubes to join into a main exhaust vent, and fired directly into the water. This would require the engine to be located at the stem of the ship and the main exhaust vent to be steerable.

3.2. Conventional Engine (lrig 3) 3.2.1. The principals of the propulsion system may be coupled with a conventional petrol or diesel engine (fig 3). The engine exhaust feeds into the pressure chamber to mix with the compressed air. A shaft driven air compressor directly from the engine provides the BP air. The remainder of the propulsion train is as before.

3.3. Steam Injection (rig 4) 3.3.1. As mentioned at 1.6.2, greater efficiency may be achieved by the injection of steam into the power train. A proposed method is as follows.

3.3.2. The combustion cylinder part of the engine (1) would be water cooled via a primary closed coolant loop. A header tank operating through a control valve (4) would allow a direct input of fresh coolant in abnormal conditions.

3.3.3. The primary loop passes through a heat exchanger (2), which is also fed by cold seawater (3). Heat is passed from the primary coolant to the seawater, which is then output towards the engine firing tube (6). 71e water in the primary loop is simultaneously cooled, with the temperature controlled by a variable speed pump (5). This configuration allows the combustion cylinder to be kept at its primary operating temperature, regardless of the demands of the steam injection system.

3.3.4. The pre-heated seawater is then routed through a nonreturn valve (7) and up the firing tube section of the engine, gaining more heat and providing a small degree of cooling for the tube itself. Near the top of the tube, the heat should be sufficient to have produced steam under pressure (9), which may then be injected. A safety valve (10) would be required for abnormally high pressures, or for when steam injection is not required.

18 4.Summ 4.1.General 4.1.1. The main advantages of this system over conventional ones is its simplicity of use and the reduction in moving parts used and, therefore, fatigue. The system could be adapted in a number of ways to meet varied requirements, e.g. varying the number of cylinders, injectors etc. or by using a conventional engine.

4.1.2. The details of the engine and propulsion system outlined in this document are the intellectual property of Mr H. McBain and are covered under current patent regulations. Public dissemination of this document is forbidden without the express permission of N1r H McBain R Annex A High Pressure Hot Gas Marine Engine And Propulsion System 5 November 1998 Key to Fic 1 1... Inlet camshaft 2... Inlet valve 3... Inlet manifold 4... Combustion cylinder 5... Direct fuel injector 6... Starting fuel injector 7... Spark plug 8... Exhaust camshaft 9... Exhaust valve 10... Non-return flap 11... Firing tube to Annex B High Pressure Hot Gas e Engine And Propulsion System 5 November 1999 Key to Fit! 2 1... Rising water lift pipe 2... Engine 3... Pressure chamber 4... Gas outlet tube 5... Forward/reverse flap 6... Water turbine/HP air compressor 7... Intake pipe (stbd) 8... Pressure release exhaust 9... Non return flaps Key to Fig 3 1... Conventional engine 2... Engine exhaust pipe 3... Compressor fan 4... Inflow of air 0 Annex C High Pressure Hot Gas Marine Engine And Propulsion System 5 November 1998 Key to Fig 4 1... Engine/combustion cylinder 2... Heat Exchanger 3... Cold/Seawater intake 4... Header Tank Valve 5... Water circulation pump 6... Warm water output 7... Non return valve 8... Firing tube 9... Steam injection 10.. Safety valve 1

Claims (8)

1) An internal combustion engine with no crankshaft or pistons using a separate source to supply the combustion cylinder or cylinders with compressed air and injected fuel The combustion cylinder or cylinders are filled and exhausted via valves opened or closed as necessary by auxiliary powered camshafts. The compressed air fuel mix is fired for cold starting by a spark plug or plugs in an open end tube injected with volatile fuel.

Fig 1.

2) The exploded gases exit the combustion cylinder via the non-return flaps in the firing tubes into the pressure chamber and exit through a direction flap directly into the water pipe system.

Fig 2.

3) The water pipe system has an inlet on each side of the ship's hull placed as low as possible. These inlet pipes join and direct water through a turbine which drives an air compressor. The engine pumps hot gas into the lift section of the water pipe the water and gas mix then discharge via the stern of the ship as high as possible below the minimum water line. All water inlets and discharge areas are steerable by vents.

Fig 2.

4) In the updated cooling system additional steam power is provided by pumping the cooling water from the engine into the pressure chamber containing the hot firing tubes.

Fig 4.

X 1:

5 Amendments to the claims have been riled as follows CLAWS 1. A high pressure hot gas manine propulsion system consisting of an internal combustion 0 0 1 In engine utilising compressed air and conventional fuel to propel fluid through a rising water lift pipe minimising moving parts by negating the need for a gearbox. dfiveshaft and propeller.

2. An internal combustion engine according to claim 1, consisting of a combustion cylinder into which a controllable compressed air supply and a flexible fuel mix is injected, ignited, and through an exhaust valve, released into a firing tube,'there to be mixed with steam under pressure to produce an adjustable supply of high pressure hot gas in accordance with the power demands of the system.

3. Apparatus according to claims 1 and 2 to inject compressed air into the combustion cylinder consisting of a water driven turbine driving an air compressor with associated inlet m'fold and valve gear.

ani m 4. Apparatus according to claims 1 and 2 to achieve high levels of compression in the combustion cylinder consisting -of a timing'system and associated valve gear.

0 Z I= 5. A Firin. tube according to claim 1 into which the high pressure gases according to cla, Z> 11r 0 im 2 are exhausted through a shock protected valve mechanism graded to air pressure and vented through a system of spring loaded non-retum flaps into a pressure direction cylinder.

6. Apparatus according to claim 1 to provide adjustable thrust by the use of a pressure direction cylinder exhausting through a system of flaps into a water lift pipe thus utilising power created by the enmne as well as the natural tendency of the body of water to move towards the 1 area of lower pressure.

7. Apparatus to allow the vessel to be manoeuvred and reversed consisting of steerable intake and exhaust vents situated in the vessels hull to be used in conjunction with the apparatus according to claim 6.

0

8. A paratus according to claim 2 to provide optimum en ine cooling, and an injection of p Z> hi eh pressure steam into the firing tube consisting of a primary cooling loop, heat exchanger and system of valves and pumps.