GB702779A - Means for supplying propellents to a rocket motor - Google Patents

Abstract

702,779. Jet propulsion engines, turbines. ARMSTRONG SIDDELEY MOTORS, Ltd. May 14, 1952 [June 6, 1951], No. 13382/51. Class 110 (3) In a rocket motor having as propellants a liquid fuel and a liquid oxidizer, i.e. liquid oxygen or a liquid oxidizing agent having a high oxygen content substantially the whole of the liquid oxidizer is vaporized and used to operate, a turbine driving the propellant pumps before entering ,the combustion chamber. The turbine 11, Fig. 1, driving pumps 59, 60 for supplying liquid fuel and liquid oxygen to the combustion chamber 15 of a rocket is supplied with working fluid from an evaporator 13 and exhausts into the combustion chamber. To start the turbine, the valve 30 is opened and pressure nitrogen, from a bottle 29 passes through a reducing valve 31 and pipes 32 to auxiliary tanks 26, 27 for liquid oxygen and liquid fuel respectively. When the pressure in the tanks 26, 27 reaches a predetermined value series-connected pressure responsive valves 34, 35 are opened and allow nitrogen under pressure (which may be supplied from the bottle 29) to flow from pipe 36 and open the valves 37, 38. The valve 37 allows liquid oxygen to flow through the non-return valve 41 and pipe 42 to an annular chamber 43 at the upstream end of the evaporator 13,and thence through holes 44, Fig. 2, into the evaporator. The valve 38 allows liquid fuel to pass through a non-return valve 46 and a pipe 47 into an annular chamber 48 and then through nozzle 49 into the evaporator. The liquid fuel and oxygen mixture is ignited by a sparking plug 51. The quantity of fuel burnt in the evaporator us only sufficient to vaporize the liquid oxygen and is therefore small. The openings 44 for the liquid oxygen are overlapped by a baffle 53 to cause the liquid oxygen to flow along the walls of the evaporator and so prevent the chilling of the flow by 3, the, excess oxygen. A further baffle 54 ensures mixing of the burnt gases with the oxygen. After the turbine has started, the fuel pump 59 discharges through a pipe 63, cooling jacket 64 and pipes 65, 66 back to the fuel tank. The rocket starting valve 67 is then in the position shown. The liquid oxygen pump 60 discharges back to the liquid oxygen tank through a valve 71. When the turbine reaches a predetermined speed; the pressurresponsive valves 73 are opened and pressure nitrogen from a pipe 72 then opens valves 71, 76. The opening of the valve 71 allows the liquid oxygen to flow to the annular space 43 and the opening of the valve 76 allows a small portion of the fuel to flow through the control valve 80 to the annular chamber 48. The operation of the non-return valves 41, 46 then cuts off the fuel and liquid oxygen supplies from the tanks 26, 27. The turbine 11 then accelerates until it reaches the speed determined by the setting of the control valve 80 and the rocket is ready for starting which is effected by movement of the valve 67 to close the return 66 and admit fuel to the pipe 18. The fuel flows through the jacket 17 to the burner 19 and is burnt in the combustion chamber 15 with the oxygen in the turbine exhaust In a modification, the turbine is started by an electric motor which is cut out when the pressure in the evaporator reaches a predetermined value. In a further modification, the turbine is started by means of gases from a cartridge passing through the turbine. In this arrangement, the pressure of the gases is arranged to open a valve in an exhaust pipe to allow the gases to flow to atmosphere. It is also stated that the oxygen liquid may be heated in a heat exchanger by the heat of the combustion chamber or by an electric heating element.