阅读说明：本技术 液体火箭发动机系统 (Liquid rocket engine system ) 是由 刘洋 于 2019-12-18 设计创作，主要内容包括：本发明公开了一种液体火箭发动机系统,该液体火箭发动机系统包括推力室和电动泵系统,电动泵系统包括用于向推力室输送燃料的燃料泵、用于向推力室输送氧化剂杀完氧化剂泵、用于驱动燃料泵和氧化剂泵转动的电机系统。本发明中采用了电动泵系统,不仅能够为发动机泵送高压推进剂,而且结构简单,同时容易实现大范围的推力调节,无需增加额外分系统。(The invention discloses a liquid rocket engine system, which comprises a thrust chamber and an electric pump system, wherein the electric pump system comprises a fuel pump for conveying fuel to the thrust chamber, an oxidant-killing pump for conveying oxidant to the thrust chamber, and an electric motor system for driving the fuel pump and the oxidant pump to rotate. The electric pump system is adopted, so that the high-pressure propellant can be pumped for the engine, the structure is simple, large-scale thrust adjustment is easy to realize, and an additional subsystem is not required to be added.)

1. A liquid rocket engine system comprising a thrust chamber and an electric pump system, wherein the electric pump system comprises:

a fuel pump for delivering fuel to the thrust chamber;

an oxidant pump for delivering oxidant to the thrust chamber;

and the motor system is used for driving the fuel pump and the oxidant pump to rotate.

2. The liquid rocket engine system according to claim 1, wherein the electric motor system includes a first electric motor system for driving rotation of the oxidant pump and a second electric motor system for driving rotation of the fuel pump;

the first motor system comprises a first motor, a first controller and a first battery pack, wherein the first motor is in transmission connection with the fuel pump to drive the oxidant pump to rotate, the first controller is used for controlling the rotating speed of the first motor, and the first battery pack is used for supplying power to the first motor and the first controller;

the second motor system comprises a second motor, a second controller and a second battery pack, wherein the second motor is in transmission connection with the fuel pump to drive the fuel pump to rotate, the second controller is used for controlling the rotating speed of the second motor, and the second battery pack is used for supplying power to the second motor and the second controller.

3. The liquid rocket engine system of claim 2, wherein the first drive shaft of the oxidizer pump and the first output shaft of the first electric machine are connected by a spline structure;

and/or a second driving shaft of the fuel pump and a second output shaft of the second motor are connected through a spline structure.

4. A liquid rocket engine system as recited in claim 1, wherein a third electric machine, a third controller, and a third battery pack are included in said electric machine system, wherein:

the fuel pump and the oxidant pump are driven to rotate by the third motor;

the third controller is used for controlling the rotating speed of the third motor;

the third battery pack is used for supplying power to the third motor and the third controller.

5. A liquid rocket engine system according to claim 4, wherein the third electric machine is provided with two output shafts, a third output shaft and a fourth output shaft, wherein:

the first driving shaft of the fuel pump is connected with the third output shaft through a spline structure;

and/or the second driving shaft of the oxidant pump is connected with the fourth output shaft through a spline structure.

6. The liquid rocket engine system according to claim 1, wherein the electric motor system includes a first dual-motor system for driving rotation of the fuel pump and a second dual-motor system for driving rotation of the oxidant pump;

the first dual-motor system comprises a fourth motor, a fourth controller, a fourth battery pack, a fifth motor, a fifth controller and a fifth battery pack, wherein: the fourth controller is used for controlling the rotating speed of the fourth motor, and the fourth battery pack is used for supplying power to the fourth motor and the fourth controller; the fifth controller is used for controlling the rotating speed of the fifth motor, and the fifth battery pack is used for supplying power to the fifth motor and the fifth controller; an output shaft of the fourth motor and an output shaft of the fifth motor synchronously rotate and are in transmission connection with the fuel pump through a first gear transmission mechanism so as to drive the fuel pump to rotate;

the second dual-motor system comprises a sixth motor, a sixth controller and a sixth battery pack, and a seventh motor, a seventh controller and a seventh battery pack, wherein: the sixth controller is used for controlling the rotating speed of the sixth motor, and the sixth battery pack is used for supplying power to the sixth motor and the sixth controller; the seventh controller is used for controlling the rotating speed of the seventh motor, and the seventh battery pack is used for supplying power to the seventh motor and the seventh controller; and the output shaft of the sixth motor and the output shaft of the seventh motor rotate synchronously and are in transmission connection with the oxidant pump through a second gear transmission mechanism so as to drive the oxidant pump to rotate.

7. The liquid rocket engine system of claim 6, wherein the first gear drive and the second gear drive are each bevel gears.

8. The liquid rocket engine system according to any one of claims 1 to 7, wherein each motor output end in the motor system is provided with a rotation speed sensor, and the rotation speed sensor is used for feeding back real-time rotation speed information to a controller;

and/or the motor in the motor system is cooled by a cooling fan;

and/or the motor in the motor system is a brushless direct current motor;

and/or the motor in the motor system can provide 350kW power output at 10000rpm when in operation.

9. A liquid rocket engine system according to any one of claims 1 to 7 wherein each electric motor in said electric motor system is powered by a respective battery pack, two or more battery strings being connected in parallel in each battery pack, a plurality of battery units being connected in series in each battery string.

10. The liquid rocket engine system according to claim 9, wherein the positive electrode of each of the battery strings is provided with a high voltage diode for preventing current reversal.

Technical Field

The invention relates to the technical field of engines, in particular to a liquid rocket engine system.

Background

And (3) secondary system: the auxiliary system is an energy supply system which is set up by the traditional liquid rocket engine for providing energy for driving the turbine, and comprises but not limited to a gas generator, an ignition device, a gas cylinder, a gunpowder starter, a valve, a pipeline, the turbine and the like, and propellant is consumed for normal work of the auxiliary system, so that the working efficiency of the liquid rocket engine is reduced.

Thrust adjustment: during the operation of the liquid rocket engine, the active change of the thrust from a design point (100% thrust) to a non-design point is called thrust adjustment. The traditional liquid rocket engine has small thrust adjusting amplitude, and the thrust can be changed only in a small way through mixing ratio adjustment. The thrust is greatly changed only by adding an additional subsystem, and the complexity of the system and the structure is further improved.

When the thrust of the engine is adjusted in a traditional mode, a thrust adjusting system (comprising a pipeline, a valve, an adjustable cavitation pipe, a specially designed injector and the like) needs to be additionally arranged, the working condition of the engine is adjusted by the thrust adjusting system through changing the flow of a liquid path of the whole system, a coupling effect is generated between the working condition and the rotating speed of a turbine pump, and finally the thrust adjustment is realized.

The circulation modes of the traditional pumping type liquid rocket engine comprise an open circulation mode and a closed circulation mode.

The open cycle is largely divided into two categories, the gasifier cycle (as shown in FIG. 1) and the thrust chamber extraction cycle (as shown in FIG. 2). The gas generator circulation system comprises an oxidant pump 101, a fuel pump 102, a turbine 103, a thrust chamber 104 and a gas generator 105; the thrust chamber pumping cycle system includes an oxidant pump 101, a fuel pump 102, a turbine 103, and a thrust chamber 104. It can be seen that in both types of cycle, the engine needs to use a part of energy to drive the turbine 103 to do work, resulting in performance loss. Adjusting the thrust simultaneously will affect the operation of the entire system. The majority of domestic long-term series carrier rocket engines in active service adopt a gas generator circulation mode. The engineering realization difficulty of the air extraction circulation mode of the thrust chamber is extremely high, and the thrust chamber is in a stage of yet to be further developed.

The closed cycle is mainly divided into an expansion cycle (as shown in fig. 3) and a post-combustion cycle (as shown in fig. 4). The expansion cycle system includes an oxidizer pump 101, a fuel pump 102, a turbine 103, and a thrust chamber 104; the afterburner system includes an oxidant pump 101, a fuel pump 102, a turbine 103, a thrust chamber 104, and a prechamber 106. It can be seen that in the two types of circulation modes, a part of energy of the engine is also required to be used for driving the turbine 103 to do work, but the medium after the work of the turbine 103 directly enters the thrust chamber 104 and can be further combusted with the propellant in the thrust chamber 104, and the performance loss caused by the mode is small. However, the engine of the expansion cycle needs to rely on the heat exchange and gasification of the propellant in the jacket of the thrust chamber 104 to drive the turbine 103 to do work, so the work-doing capacity is limited. Meanwhile, the turbo pump of the expansion cycle engine has high rotating speed and is often a flexible rotor working in a transcritical mode, so that large-range stepless thrust adjustment cannot be realized. The afterburning circulation system is the most complex, all components work under high pressure, the structural mass of the engine is large, and the development cost is high.

In summary, conventional pump-type liquid rocket engines (prior art) all use a turbo pump system to transport the propellant, and the pumping medium provides a thrust chamber for combustion to generate thrust. The liquid rocket engine adopting the turbine pump system has the advantages that the coupling degree of the auxiliary system and the main system is very high, the energy of the system needs to be consumed additionally and is provided for the turbine (about 4-6% of the main system), and due to the existence of the gas generator, the pipeline, the valve and the like and the low energy conversion efficiency of the turbine and other reasons, on one hand, the mode can cause energy waste, on the other hand, the complexity of the engine system and the structure is greatly improved, and more importantly, the thrust adjusting difficulty of the engine is increased.

It can be seen that the four traditional circulation modes of the traditional pumping type liquid rocket engine have advantages and disadvantages respectively, but have larger limitations in the aspects of energy utilization efficiency and stepless regulation of engine thrust. With the development of aerospace in various countries in the world, particularly the vigorous development of commercial aerospace, the increasingly rich application scene requirements of human beings on spacecrafts and liquid rocket engines cannot be met.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a liquid rocket engine system, which employs an electric pump system, and can directly adjust the rotation speed of a fuel pump and an oxidant pump through an electric motor, so as to adjust the thrust of the engine without adding an additional subsystem.

In order to achieve the purpose, the invention provides the following technical scheme:

a liquid rocket engine system comprising a thrust chamber and a motor pump system, wherein the motor pump system comprises:

a fuel pump for delivering fuel to the thrust chamber;

an oxidant pump for delivering oxidant to the thrust chamber;

and the motor system is used for driving the fuel pump and the oxidant pump to rotate.

Preferably, in the above liquid rocket engine system, the electric motor system includes a first electric motor system for driving the oxidant pump to rotate and a second electric motor system for driving the fuel pump to rotate;

the first motor system comprises a first motor, a first controller and a first battery pack, wherein the first motor is in transmission connection with the fuel pump to drive the oxidant pump to rotate, the first controller is used for controlling the rotating speed of the first motor, and the first battery pack is used for supplying power to the first motor and the first controller;

the second motor system comprises a second motor, a second controller and a second battery pack, wherein the second motor is in transmission connection with the fuel pump to drive the fuel pump to rotate, the second controller is used for controlling the rotating speed of the second motor, and the second battery pack is used for supplying power to the second motor and the second controller.

Preferably, in the above liquid rocket engine system, the first drive shaft of the oxidizer pump and the first output shaft of the first electric machine are connected by a spline structure;

and/or a second driving shaft of the fuel pump and a second output shaft of the second motor are connected through a spline structure.

Preferably, in the above liquid rocket engine system, the electric machine system includes a third electric machine, a third controller, and a third battery pack, wherein:

the fuel pump and the oxidant pump are driven to rotate by the third motor;

the third controller is used for controlling the rotating speed of the third motor;

the third battery pack is used for supplying power to the third motor and the third controller.

Preferably, in the above liquid rocket engine system, the third electric machine is provided with two output shafts, namely a third output shaft and a fourth output shaft, wherein:

the first driving shaft of the fuel pump is connected with the third output shaft through a spline structure;

and/or the second driving shaft of the oxidant pump is connected with the fourth output shaft through a spline structure.

Preferably, in the above liquid rocket engine system, the electric motor system includes a first dual-electric motor system for driving the fuel pump to rotate and a second dual-electric motor system for driving the oxidizer pump to rotate;

the first dual-motor system comprises a fourth motor, a fourth controller, a fourth battery pack, a fifth motor, a fifth controller and a fifth battery pack, wherein: the fourth controller is used for controlling the rotating speed of the fourth motor, and the fourth battery pack is used for supplying power to the fourth motor and the fourth controller; the fifth controller is used for controlling the rotating speed of the fifth motor, and the fifth battery pack is used for supplying power to the fifth motor and the fifth controller; an output shaft of the fourth motor and an output shaft of the fifth motor synchronously rotate and are in transmission connection with the fuel pump through a first gear transmission mechanism so as to drive the fuel pump to rotate;

the second dual-motor system comprises a sixth motor, a sixth controller and a sixth battery pack, and a seventh motor, a seventh controller and a seventh battery pack, wherein: the sixth controller is used for controlling the rotating speed of the sixth motor, and the sixth battery pack is used for supplying power to the sixth motor and the sixth controller; the seventh controller is used for controlling the rotating speed of the seventh motor, and the seventh battery pack is used for supplying power to the seventh motor and the seventh controller; and the output shaft of the sixth motor and the output shaft of the seventh motor rotate synchronously and are in transmission connection with the oxidant pump through a second gear transmission mechanism so as to drive the oxidant pump to rotate.

Preferably, in the above liquid rocket engine system, the first gear transmission mechanism and the second gear transmission mechanism are both bevel gear transmission mechanisms.

Preferably, in the liquid rocket engine system, each motor output end of the motor system is provided with a rotation speed sensor, and the rotation speed sensors are used for feeding back real-time rotation speed information to the controller.

Preferably, in the liquid rocket engine system, the motor in the motor system is cooled by a cooling fan.

Preferably, in the above liquid rocket engine system, the motor in the motor system is a brushless dc motor.

Preferably, in the above liquid rocket engine system, the motor in the motor system is operated to provide a power output of 350kW at 10000 rpm.

Preferably, in the above liquid rocket engine system, each motor in the motor system is respectively powered by one battery pack, two or more battery strings are respectively connected in parallel in each battery pack, and a plurality of battery units are respectively connected in series in each battery string.

Preferably, in the above liquid rocket engine system, the positive electrode of each of the battery strings is provided with a high-voltage diode for preventing a reverse current.

According to the technical scheme, the liquid rocket engine system provided by the invention has the following advantages:

1) because the motor is adopted to replace a turbine, the number of parts such as one path of liquid, one path of gas path, related pipelines, valves, gas generators and the like is greatly reduced, and the system of the invention is greatly simplified for the engine.

2) The controller is adopted to directly adjust the rotating speed of the motor, so that a thrust adjusting system is reduced, the thrust adjusting system comprises but is not limited to a thrust adjusting valve (comprising a motor, a valve body and the like), an adjustable cavitation erosion pipe (comprising a motor, a cavitation pipe, a pipe needle and the like), a movable true bolt type injector, a pipeline, a valve controller, a cable and other components, the application is simpler and more convenient in the aspect of engine thrust adjustment, and the structure is simpler.

3) Because the controller is adopted to directly adjust the rotating speed of the motor, the response time of the thrust adjustment of the engine only depends on the response time of the controller and the motor, no other link exists, and the thrust adjustment system has faster response compared with the traditional thrust adjustment system (needing controller-regulating valve-cavitation tube-injector-gas generator-turbine full-path feedback).

4) The engine has simple integral structure after the electric pump system is adopted, so the invention can obviously reduce the weight of the engine, and the estimated total weight of the structure of the electric pump system is less than 60kg, and compared with the structure adopting a gas generator-turbine auxiliary system under the same working condition, the structure weight is reduced by about 30 percent.

5) Because the motor is adopted to drive the pump, the pressure after the pump can be increased only by starting the motor, then the thrust chamber is ignited, the rated working condition can be gradually reached, and the circulating starting is not needed (namely, the turbine is blown to rotate firstly to enable the pump to reach a certain pressure, then the gas generator is ignited, and the turbine is continuously blown by the gas generated by the gas generator to reach the rated working condition), so that the starting of the engine is easy, and the use of initiating explosive devices is also avoided.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a basic schematic diagram of a gasifier cycle of a conventional pumped liquid rocket engine;

FIG. 2 is a basic schematic diagram of the evacuation cycle of the thrust chamber 104 of a conventional pumped liquid rocket engine;

FIG. 3 is a basic schematic diagram of an expansion cycle of a conventional pumped liquid rocket engine;

FIG. 4 is a basic schematic diagram of a post-combustion cycle of a conventional pumped liquid rocket engine;

FIG. 5 is a detailed schematic diagram of a motor-driven pump system according to a first embodiment of the present invention;

FIG. 6 is a detailed schematic diagram of a motor-driven pump system according to a second embodiment of the present invention;

FIG. 7 is a schematic diagram of a liquid rocket engine system according to a second embodiment of the present invention;

FIG. 8 is a schematic diagram of a basic connection structure of a motor-driven pump system according to a second embodiment of the present invention;

fig. 9 is a schematic diagram illustrating a detailed principle of a dual-motor system according to a third embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

First embodiment

Referring to fig. 5, fig. 5 is a schematic diagram illustrating a detailed principle of the motor-driven pump system according to the first embodiment of the present invention.

The liquid rocket engine system according to the first embodiment of the present invention includes a thrust chamber 104 and an electric pump system including a fuel pump 102, an oxidizer pump 101, and an electric motor system. Wherein: the fuel pump 102 is used to deliver fuel to the thrust chamber 104; the oxidizer pump 101 is used to deliver oxidizer to the thrust chamber 104; the motor system is used to drive the fuel pump 102 and the oxidizer pump 101 to rotate.

It can be seen that the liquid rocket engine system provided by the first embodiment of the present invention employs an electric pump system, i.e. an electric motor system to drive and regulate the rotation speed of the fuel pump 102 and the oxidizer pump 101. The rotating speeds of the fuel pump 102 and the oxidant pump 101 can be directly adjusted through the motor, so that the thrust of the engine can be adjusted without adding an additional subsystem.

Specifically, as shown in fig. 5, the above-described motor system includes a first motor system for driving the oxidizer pump 101 to rotate and a second motor system for driving the fuel pump 102 to rotate. Wherein:

the first motor system comprises a first motor 211, a first controller 212 and a first battery pack 213, the first motor 211 is in transmission connection with the oxidant pump 101 to drive the oxidant pump 101 to rotate, the first controller 212 is used for controlling the rotating speed of the first motor 211, and the first battery pack 213 is used for supplying power to the first motor 211 and the first controller 212;

the second motor system comprises a second motor 221, a second controller 222 and a second battery pack 223, wherein the second motor 221 is in transmission connection with the fuel pump 102 to drive the fuel pump 102 to rotate, the second controller is used for controlling the rotation speed of the second motor, and the second battery pack is used for supplying power to the second motor and the second controller.

Specifically, a first driving shaft of the oxidant pump 101 and a first output shaft of the first motor 211 are connected by a spline structure; and/or, the second driving shaft of the fuel pump 102 is connected with the second output shaft of the second motor through a spline structure.

Specifically, each motor output end in the motor system is provided with an independent rotating speed sensor, and the rotating speed sensors are used for feeding back real-time rotating speed information to the controller so as to realize accurate control and adjustment.

Specifically, under some application conditions, a heat dissipation fan may be added to the tail end of each motor in the motor system, and the heat dissipation fan may function to cool the motor through air circulation.

Specifically, the motors in the motor system are all brushless direct current motors, and the motors can provide 350kW power output at 10000rpm (revolutions per minute).

Specifically, each motor in the above motor system is respectively powered by one battery pack, two or more battery strings are respectively connected in parallel in each battery pack, and a plurality of battery units are respectively connected in series in each battery string. Further, the positive electrode of each battery string is provided with a high-voltage diode for preventing current reversal.

When the liquid rocket engine system provided by the first embodiment of the invention works, the pumps (the oxidizer pump 101 and the fuel pump 102) can be driven to rotate at a high speed through the motor system, the low-pressure propellant and the low-pressure fuel are respectively and directly pumped into the thrust chamber from the oxidizer storage tank and the fuel storage tank, the combustion is organized to generate thrust, each battery pack respectively provides electric energy for the motor correspondingly connected with the battery pack, and each motor respectively drives the corresponding pump to rotate at the rotating speed required by the system under the control of the controller correspondingly connected with the motor.

When the working condition is changed, the first controller 212 sends out an adjusting signal, the rotating speed of the first motor 211 is changed, and the head and the flow of the oxidant pump 101 are changed along with the change of the rotating speed; the second controller 222 sends out an adjustment signal, the rotation speed of the second motor 221 changes, and the head and the flow rate of the fuel pump 102 change along with the change of the rotation speed. Thus, the gas flow rate and the chamber pressure of the thrust chamber 104 are changed, thereby achieving adjustment of the engine thrust. The response speed of the adjustment mode only depends on the rotation speed adjustment response of a controller-motor, and the traditional circulation mode thrust adjustment system can act on the rotation speed of the turbine pump after the feedback of a complex path of a pump-a cavitation erosion pipe-an injector-a combustor-a turbine nozzle-a turbine, and the response speed is slow.

It can be seen that, in the liquid rocket engine system provided in the first embodiment of the present invention, the scheme of "battery pack-controller-motor-pump" is adopted to replace the scheme of "auxiliary system-turbine-pump" of the conventional liquid rocket engine, so that the function of pumping high-pressure propellant can be realized in a simpler system and structure form, and at the same time, the function of thrust adjustment in a large range can be realized only by adjusting the rotation speed of the motor, without separately adding a thrust adjustment system, so that the structure of the liquid rocket engine is greatly simplified, the weight of the engine is reduced, the thrust-weight ratio is increased, and the effective load of the rocket is increased.

Moreover, the motor-driven pump system forms a novel liquid rocket engine circulation mode, the circulation mode is simple, the oxidant at the outlet of the oxidant pump 101 and the fuel at the outlet of the fuel pump 102 directly enter the main thrust chamber 104 to be combusted to generate thrust, extra consumption of propellant is avoided, meanwhile, the controller can directly adjust the rotating speed of the motor, a complex thrust adjusting system is not needed, a speed block is adjusted, and the adjustment mode is simple and reliable. The structure of the auxiliary system in the prior art is eliminated, so that the structure of the engine system is simplified, and the weight is reduced.