JPH0192560A - Rocket launcher - Google Patents

Abstract

PURPOSE:To improve combustion efficiency in a rocket having two kinds of fuel and liquid for propulsion agent by providing a fuel jet for sending atomized main liquid fuel info sub-fuel jet jetted under the gasified state and a liquid oxygen jet coaxial with said fuel jet. CONSTITUTION:In a rocket engine liquid oxygen, kerosene and hydrogen respectively for oxidizing agent, fuel and sub-fuel, liquid hydrogen 4 as sub-fuel is sent by a pump 8, and a portion of the sub-fuel is jetted from an injector 1 into a combustor 5, while the remaining is sent to a high temperature gas generator 6 to be burnt with the liquid oxygen 2 being supplied by a pump 8'. Pumps 8-8'' are driven through turbines 7, 7' with high temperature gas generated by said generator 6. Main fuel 3 is forced into the combustor 5 by the pump 8''. Then, the main fuel 3 and liquid oxygen 2 are jetted into the combustor 5 respectively from a jet 13 and an oxygen jet 12 provided in the center of a jet 14. A hydrogen jet 14' is opened to the upstream side wall of jet 14 to supply the sub-fuel 4.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention is a rocket injector for stably burning fuel such as liquid hydrocarbon, and in particular for stably burning multiple types of fuel with different physical properties with high efficiency. Regarding rocket injectors for (prior art) Conventionally, rocket engines using high-density hydrocarbons such as kerosene and oxidizers such as liquid oxygen have been widely used.

In the case of conventional rocket engines that use propellants that are a combination of liquid fuels such as liquid oxygen and kerosene, the nozzle shape of the injector used for the purpose of atomizing the propellant and promoting mutual mixing of the propellants is It is shown in Figure 6. The kerosene 3 is sprayed into the combustion chamber from the fuel injection port 10 via the fuel supply port. On the other hand, since it is greatly affected by the machining accuracy of the nozzle machining, there are often differences in the furnace firing performance obtained even with nozzles with the same design dimensions. In addition, the propellant jet at the collision point and the propellant atomization mechanism after the collision are easily affected by the surrounding furnace combustion gas flow and easily become unstable, which may induce harmful vibration furnace combustion. Cheap.

Further, it has the disadvantage that the thermal load on the injection surface tends to be excessive. For this reason, much effort has been required to design and construct rocket engine injectors that use propellants such as liquid oxygen and kerosene.

On the other hand, in recent years, the ultimate form of flying vehicle using a rocket engine is thought to be a winged return platform (SSTOI) that can be used many times, similar to an aircraft, and there are many efforts to realize this. Attempts have been made to create a plan.In order to realize such a 5STO system, it is necessary to sequentially change the plan.

For example, in order to realize S S TO'ii with a serial combustion engine that switches and burns two types of propellant combinations (Mode 1, which operates at low altitudes from launch, and Mode 2, which operates at high altitudes), theoretical analysis is required. According to It is a necessary condition that I1 ρ111>ρ212. Specific propellant combinations that meet this condition have been proposed for mode 1: oxidizer: liquid oxygen fuel: high-density hydrocarbons including kerosene, or light hydrocarbons such as liquefied methane and propane. The rocket engine for 5STO is basically a rocket injector corresponding to each mode, or an individual injector corresponding to each propellant with a dual integrated injector. It was the only one with a configuration that had This is due to the physical properties of the different fuels corresponding to each mode. For example, if kerosene is used as the red material in mode 1 among the above combinations of oxidizer and fuel, the density will be approximately 800 to 110.
0 kr/m3, the boiling temperature is 220-280℃, whereas liquid hydrogen in mode 2 has a density of about 70kg.
/rn3, the boiling temperature is -253°C and the physical properties of the two fuels are different at the cylinder end, and it is possible to achieve good atomization of the propellant and good mixing between the propellants using one injector. becomes extremely difficult. Therefore, the conditions necessary for combustion temperature cannot be achieved, the concubinage rate is high, and stable combustion cannot be achieved.

Achieve optimal combustion conditions with one injector, even when
The aim is to achieve highly efficient combustion.

(Means for Solving the Problems) The rocket injector of the present invention includes a nozzle for vaporized liquid hydrogen, a fuel nozzle for feeding liquid fuel into a jet stream ejected from the hydrogen nozzle to atomize it, and the fuel nozzle. The liquid oxygen nozzle is configured as a coaxial nozzle, and is particularly advantageously implemented.
A liquid rocket engine that uses different types of fuel, for example kerosene, liquid hydrogen, and liquid oxygen as propellants, and first burns mainly the first fuel and liquid oxygen, then switches to the second fuel and burns it in the same combustor. When the first main fuel, such as kerosene, and liquid oxygen are burned, the fuel atomization gas is a vaporized fuel gas that cools the rocket nozzle and the rocket combustion chamber, for example. Alternatively, it may be combustion gas from a high-temperature gas generator.

(Examples) Hereinafter, the present invention will be described in detail by examples with reference to the drawings. In this example, a case is shown in which the present invention is implemented as a rocket engine for 5STO, and as an example of fuel combinations, liquid oxygen is used as an oxidizer as a mode 1 propellant, kerosene is used as a fuel, and as a secondary fuel. Hydrogen,
The case where liquid oxygen and liquid hydrogen are used for mode 2 is shown.

That is, when operating in mode 1 shown in FIG. 1(1)K,
The liquid hydrogen 4 used as the secondary fuel cools the rocket nozzle 9 and the rocket combustion chamber by the pump 8, and part of it is injected from the injector 1 into the combustor 5 and is also sent to the high-temperature gas generator 6. After driving the pump 8.8.8, it is evacuated to the nozzle 9. Further, the main fuel 3 is pumped into the combustion chamber 5 by a pump 8''.

In mode 2 shown in FIG. 1(2), only liquid hydrogen 4 is used as fuel, and the operation of each part is the same as in the case of FIG. Although the same injector is used in both cases,
The details are shown in Figure 2. In the figure (1), in mode 1, kerosene 3, which is the main propellant, is ejected from the nozzle 13, and liquid oxygen 2 is ejected from the oxygen nozzle 12 provided at the center of the nozzle 14 into the combustor. On the upstream side wall of the fuel nozzle 14,
The hydrogen injection port 14' is open, and gasified hydrogen as a hydrant is ejected into the fuel injection port 14.

In mode 1, the mass ratio of liquid oxygen and kerosene is smaller, but the volume ratio is about 10 to 100 times larger. Figure 2 (2
) (3) shows a cross section at 13 hydrogen ejection ports. The gaseous hydrogen jet injected at high speed transforms the liquid propellant kerosene, which flows perpendicularly, obliquely, or tangentially to the flow through a circular hole or slit-like channel, into fine particles at position a by the energy of this hydrogen jet. ◇Furthermore, this high-speed flow containing fine particles contacts the liquid oxygen injected from the center of the coaxial nozzle at position b, realizing atomization of the liquid oxygen and a good mixing state with the fuel.

When switching to mode 2, the injection of kerosene is stopped and residual kerosene is purged with helium gas or the like. Thereafter, the interaction between the high-speed flow of hydrogen and the jet of liquid oxygen causes atomization and mixing, which is the same as with conventional coaxial nozzles for liquid oxygen and liquid hydrogen.

direct), kerosene fuel (density 860~/m3, viscosity W
5 mi'/a, both cases at 15°C) and hydrogen (
Density 7-8 kg/-s, viscosity 1.12 xyi'/
! I, both directly at 15° C. and 100 atm pressure. The injection mass ratio is liquid oxygen: kerosene: hydrogen =
2.6:0.9:0.1, soot burning pressure IQ MPa (
Good combustion was demonstrated under conditions of approximately 1001Q/cm2), that is, stable combustion with a combustion efficiency of approximately 98- or higher.

Note that 15 in the figure indicates a flow path for ignition torch gas.

FIG. 4 shows another embodiment, which is a further improvement on the embodiment shown in FIG. That is, in order to further promote the atomization of the liquid oxygen injected in the form of a liquid column from the circular cross-section nozzle shown in FIG. The device is designed to inject liquid oxygen in a thin film form. The liquid oxygen is injected in a thin film state, and furthermore, this high-speed spray flow efficiently atomizes the thin film liquid oxygen at the position b and promotes the mixing of the two. In mode 2, the injection of kerosene is stopped, residual kerosene is purged with helium gas, etc., and then atomization and mixing are performed by interaction between a high-speed flow of hydrogen and a jet of liquid oxygen in the form of a thin film.

FIG. 5 shows the high temperature gas generator 6 and combustor 5 shown in FIG.
This figure shows the details of the injector 1, which does not directly inject low-temperature gaseous hydrogen in mode 1. The low-temperature gaseous hydrogen 4 after cooling in the furnace chamber is smoldered to generate high-temperature gas in the range of 300 to 800°C to increase the flow rate of the working gas for atomization.

In this case, the generation of high-temperature gas for atomization is a method of generating the following two gases. The second method is to control the mass flow rate of branched liquid oxygen 2' in the range of 180 to 90 with respect to the hydrogen mass flow rate 1, which is a secondary propellant, and to heat the liquid at a high temperature of 300 to 800°C by so-called oxygen enriched furnace firing. This is a method of generating gas. In the second method, the amount of high-temperature gas for atomization can be increased by about 100 times compared to the first method. If it is expected that the atomization characteristics are not satisfactory with the first method, the second method
It is preferable to use this method. The structures of the main fuel nozzle and the single granulation gas nozzle are the same as those shown in FIGS. 2 and 4. In mode 2, the structure is the same as that of the above embodiment.

(Effects of the Invention) The rocket injector of the present invention has a simple structure as described above, and improves the mixing conditions of fuel and oxidizer. In particular, the rocket injector improves the mixing conditions of the fuel and the oxidizer, and in particular, the rocket injector of the present invention improves the mixing conditions of the fuel and the oxidizer. Or, it is a high-temperature gas with a high concentration of hydrogen or oxygen after the turbine of a turbo pump is driven, which is inevitably generated when configuring a dual-fuel rocket cycle, which makes the rocket configuration complicated. It has the remarkable effect of not being

[Brief explanation of the drawing]

Figure 1 is a conceptual diagram of the operating system of a dual-fuel rocket engine.
FIG. 2 is a cross-sectional view showing the nozzle structure of one embodiment of the rocket injector of the present invention, FIG. 3 is a cross-sectional and front view showing an injector using the nozzle, and FIG. 4 is another embodiment of the nozzle structure. FIG. 5 is a cross-sectional view showing the structure of a high-temperature gas generator and the injector of the present invention; FIG. 6 is a cross-sectional view showing the structure of a conventional liquid oxygen and kerosene fuel propellant injector; The codes inside are respectively 1: Injector 2: Liquid oxygen 3: Kerosene base nozzle 13
: Hydrogen spout 15: Ignition torch gas outlet 16: Pre-combustion chamber. (1) Figure 1-1 Figure 1-2 Figure 3-2 Figure 5 °＼ Figure 6

Claims (1)

[Claims] 1) In a rocket using two types of fuel with different physical properties and liquid oxygen as propellants, the liquid main fuel is fed into the jet of the secondary fuel ejected from the nozzle in a gaseous state and atomized. A rocket injector comprising a fuel nozzle and a liquid oxygen nozzle configured as a coaxial nozzle with the fuel nozzle. 2) A liquid rocket engine uses two types of fuel with different physical properties and liquid oxygen as propellants, and first burns mainly the first fuel and liquid oxygen, then switches to the second fuel and burns it in the same combustor. When a combustor burns a first fuel and liquid oxygen, the first fuel is fed into a jet of vaporized second fuel, and the jet atomizes the first fuel to form a liquid 3) A rocket injector characterized in that the fuel is mixed and combusted with oxygen.3) The fuel atomization gas is a vaporized gas of the fuel that has cooled the rocket nozzle and the rocket combustion chamber.Claim 1 4) Rocket injector according to Claim 1, wherein the fuel atomization gas is combustion gas from a high-temperature gas generator 5) The fuel atomization gas The rocket injector according to claim 4, wherein is fuel-rich combustion gas of a high-temperature gas generator.