Abstract

A simulation method for dynamic contact characteristics of a high-speed heavy-load ball bearing in a liquid rocket engine, mainly including: establishing a low-speed heavy-load ball bearing model of a liquid rocket engine according to a normal contact stress of a ball bearing, and performing iterative computation on the low-speed heavy-load ball bearing model of the liquid rocket engine to obtain static contact characteristics of the heavy-load ball bearing; establishing a high-speed heavy-load ball bearing model of the liquid rocket engine based on a theory of quasi-static analysis; and taking computed values for the static contact characteristics of the heavy-load ball bearing as initial values, substituting the initial values into the high-speed heavy-load ball bearing model, and performing iterative operation through a dual-population co-evolutionary particle swarm optimization (CPSO) algorithm to obtain dynamic contact characteristics of each of balls in the ball bearing.

IPC Classes  ?

• G06F 30/20 - Design optimisation, verification or simulation
• G06F 17/11 - Complex mathematical operations for solving equations
• G06F 119/14 - Force analysis or force optimisation, e.g. static or dynamic forces

Abstract

A lunar base energy supply and application system based on photocatalytic water splitting hydrogen production technology are provided. The system includes a solar photovoltaic power generation unit, a power management unit, a water storage tank, a photocatalytic water splitting unit, an hydrogen-oxygen storage unit, an hydrogen-oxygen-water conversion unit, a condition monitoring unit, a chemical propulsion unit, an environmental control and life support unit, and a load. The photocatalytic water splitting unit and the hydrogen-oxygen-water conversion unit can generate hydrogen and oxygen, and the solar photovoltaic power generation unit and the hydrogen-oxygen-water conversion unit can generate electric power, thus ensuring stable supply of energy at the lunar base.

IPC Classes  ?

• C25B 1/04 - Hydrogen or oxygen by electrolysis of water
• B64G 99/00 - Subject matter not provided for in other groups of this subclass
• C25B 1/55 - Photoelectrolysis
• C25B 15/08 - Supplying or removing reactants or electrolytesRegeneration of electrolytes
• H01M 8/0656 - Combination of fuel cells with means for production of reactants or for treatment of residues with means for production of gaseous reactants by electrochemical means
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers
• H02S 10/10 - PV power plantsCombinations of PV energy systems with other systems for the generation of electric power including a supplementary source of electric power, e.g. hybrid diesel-PV energy systems

Abstract

The present application relates to the technical field of injectors. Disclosed is a variable thrust pintle type injector, which aims to solve the problems of a complex structure and low operating reliability of an injector due to strict operating environment conditions required for mechanical actuation regulation. The variable thrust pintle type injector comprises a housing, a central cylinder, and a pintle. The housing has a first through cavity, wherein a first flow channel for introducing a first propellant is formed in the housing, and the first flow channel is in communication with the first cavity. The central cylinder is nested in the first cavity and has a second cavity for introducing a second propellant, and a second flow channel is provided in an end of the central cylinder close to a combustion chamber. The pintle is arranged between the central cylinder and the housing, and a third flow channel is formed between an inner wall of the housing and an outer wall of the pintle. When the pintle moves in a direction away from the combustion chamber, the areas of outlet ends of the first flow channel and the second flow channel blocked by the pintle are gradually reduced. The central cylinder is further provided with a fourth flow channel for injecting an actuation fluid to an upper portion of the pintle.

IPC Classes  ?

• F02K 9/52 - Injectors
• F02K 9/62 - Combustion or thrust chambers

Abstract

The present application relates to the technical field of rotor system dynamics, discloses a rotor system dynamic characteristic calculation method and device based on a finite element method, and a medium, and is used for providing a process and numerical algorithm for solving rotor characteristics by using the finite element method. The rotor system dynamic characteristic calculation method based on the finite element method comprises: calculating a motion equation of the disc on the basis of an Euler angle rotation transformation matrix; calculating a motion equation of the elastic shaft by utilizing a displacement interpolation function matrix; calculating a motion equation of a bearing on the basis of a journal center coordinate of the bearing; determining a motion equation of the rotor system on the basis of the motion equation of the disc, the motion equation of the elastic shaft, and the motion equation of the bearing; and calculating a critical rotating speed and an unbalance response of the rotor system on the basis of the motion equation of the rotor system.

IPC Classes  ?

• G06F 30/17 - Mechanical parametric or variational design

Abstract

A ball bearing fault determination method and apparatus, and a storage medium, relating to the technical field of rolling bearings. The ball bearing fault determination method comprises: acquiring vibration signals of a ball bearing, and on the basis of a wavelet packet decomposition method, performing noise cancellation processing on signals in each time period of the vibration signals, so as to obtain signals in each time period subjected to the noise cancellation processing (S100); by using short-time Fourier transform, performing time-frequency analysis on the signals in each time period, so as to obtain a time period in which a ball bearing fault occurs, and a fault frequency corresponding to the time period (S200); by using a Choi-Williams distribution-based time-frequency analysis method, performing refinement analysis on the signals in the time period in which the ball bearing fault occurs, and when the fault frequency comprises a fault characteristic frequency of the ball bearing, according to the fault characteristic frequency of the ball bearing, determining a fault duration corresponding to the fault characteristic frequency (S300); and according to the fault characteristic frequency of the ball bearing and the fault duration corresponding to the fault characteristic frequency, determining the fault type and the fault severity of the ball bearing (S400).

IPC Classes  ?

• G01M 13/045 - Acoustic or vibration analysis

Abstract

Disclosed in the present application are a flow guide structure and device for measuring the uniformity of a cooling path jet, which structure and device relate to the technical field of liquid rocket engines, and solve the problem of it being difficult for a conventional measuring tool to perform collection and measuring when the distance between adjacent cooling holes is too small. The flow guide structure for measuring the uniformity of a cooling path jet comprises a plurality of flow guide sections circumferentially arranged on an outer side of the flow guide structure. In the direction from inlet ends of the flow guide sections to outlet ends of the flow guide sections, the distance between center lines of every two adjacent flow guide sections gradually increases, the plurality of flow guide sections correspondingly communicate with a plurality of cooling holes, and each flow guide section is configured to guide a collected cooling path jet beam to an outlet of the corresponding flow guide section, and to finally guide the cooling path jet beam into a collection structure. The device for measuring the uniformity of a cooling path jet comprises the flow guide structure for measuring the uniformity of a cooling path jet mentioned in the above technical solution. The flow guide structure for measuring the uniformity of a cooling path jet that is provided by the present application is configured to measure the uniformity of a cooling path jet when the distance between the adjacent cooling holes is relatively small.

IPC Classes  ?

• F02K 9/96 - Rocket-engine plants, i.e. plants carrying both fuel and oxidant thereforControl thereof characterised by specially adapted arrangements for testing or measuring
• G01M 15/00 - Testing of engines

Abstract

A pintle injector, comprising a housing, a central cylinder, a central rod, and a pintle. The central cylinder is located in the housing and is fixedly connected to the housing. The pintle is located between the housing and the central cylinder, and can move along an axial direction of the housing. The central rod is located in the central cylinder and is fixedly connected to the central cylinder. The housing is provided with a first cavity, and a first propellant flow channel in communication with the first cavity. When a first propellant enters the first propellant flow channel along the first cavity, the pintle moves along the axial direction of the housing under the action of the first propellant, so that the first propellant enters a first gap formed between the pintle and the housing from the first propellant flow channel, and is sprayed out along the first gap. This is used to solve the problem of working reliability of a pintle injector being affected due to poor consistency in assembling a central assembly of the pintle injector. Further disclosed is a thrust chamber, comprising a combustion chamber, a spray tube assembly and the pintle injector.

IPC Classes  ?

• F02K 9/52 - Injectors
• F02K 9/62 - Combustion or thrust chambers

Abstract

The present disclosure provides a laser target, including a laser target body and two laser transceiving devices, wherein each laser transceiving device includes a receiver and an emitter opposite to each other; a plurality of emitting tubes are arranged on the emitter at equal intervals, a plurality of receiving tubes are arranged on the receiver at equal intervals, and the emitting tubes and the receiving tubes are in one-to-one correspondence; and a target distance between two adjacent emitting tubes is smaller than a diameter of a bullet; laser emitted by the emitter of one of the two laser transceiving device is vertical to laser emitted by the emitter of an other of the two laser transceiving device to form a laser net; and a target surface of the laser target body is arranged in a direction vertical to a projection of the laser net.

IPC Classes  ?

• F41J 5/02 - Photo-electric hit-detector systems
• F41J 5/14 - Apparatus for signalling hits or scores to the shooter, e.g. manually operated, or for communication between target and shooterApparatus for recording hits or scores

Abstract

Disclosed is a method for simulating the contact dynamic characteristics of high-speed heavy-load ball bearings in a liquid rocket engine, the primary implementation steps thereof being: in accordance with the contact normal stress of a ball bearing, establishing a low-speed heavy-load ball bearing model for a liquid rocket engine, and performing iterative calculations on the low-speed heavy-load ball bearing model for the liquid rocket engine so as to obtain static contact mechanics characteristics for the heavy-load ball bearing; on the basis of quasi-static analysis theory, establishing a high-speed heavy-load ball bearing model for the liquid rocket engine; using a calculated value of heavy-load ball bearing static contact mechanics characteristics as an initial value, substituting same into the high-speed heavy-load ball bearing model, and iterating via a dual-population co-evolutionary particle swarm algorithm to obtain contact dynamic characteristics of each ball in the ball bearing. By means of the method, it is possible to obtain contact dynamic characteristics parameters and rules of change for a liquid rocket engine ball bearing from a static state to a dynamic state, from a single load to a combined load and from low rotational speed to extremely high rotational speed.

IPC Classes  ?

• G06F 30/20 - Design optimisation, verification or simulation
• G06F 30/15 - Vehicle, aircraft or watercraft design
• G06F 30/17 - Mechanical parametric or variational design
• G06F 119/14 - Force analysis or force optimisation, e.g. static or dynamic forces

Abstract

The present invention relates to the field of friction-resistant materials, and relates to a friction-resistant high shear resistant composite rubber sealing material. The present invention provides a friction-resistant high shear resistant composite rubber sealing material, comprising the following raw materials in parts by weight: 0.1-10 parts of a friction-resistant active surface modified resin and 50-90 parts of semi-vulcanized rubber. The structural formula of the friction-resistant active surface modified resin is as shown in formula I, wherein 0 < m ≤ 200 and 0 < n ≤ 200. According to the present invention, different carbon chain length soft segments containing polyetheramine are introduced into the main chain of semi-aromatic polyamide plastic molecules, so that excellent flexibility and stress deformation resilience are imparted to the traditional semi-aromatic polyether amide while maintaining good friction performance. According to the present invention, the active carboxyl groups are introduced into the main chain of polymer molecules by copolymerization, so that the interface bonding force between the material and the rubber product is greatly improved by means of the effects of an intermolecular hydrogen bond, the van der Waals force, etc., thereby solving the problems of poor interface bonding force and poor shear resistance of the traditional rubber-plastic composite material.

IPC Classes  ?

• C08J 7/046 - Forming abrasion-resistant coatingsForming surface-hardening coatings
• C08J 7/12 - Chemical modification
• C09D 181/06 - PolysulfonesPolyethersulfones
• C09D 171/10 - Polyethers derived from hydroxy compounds or from their metallic derivatives from phenols
• C08G 75/23 - Polyethersulfones
• C08G 65/48 - Polymers modified by chemical after-treatment
• C08G 65/40 - Macromolecular compounds obtained by reactions forming an ether link in the main chain of the macromolecule from hydroxy compounds or their metallic derivatives derived from phenols from phenols and other compounds
• C08L 21/00 - Compositions of unspecified rubbers

Abstract

The present invention relates to a lunar base energy supply and application system based on the technology of hydrogen production by means of water photolysis, so as to solve the problems of a single energy supply mode being unable to meet energy demands of a lunar base since the energy demands of long-term tasks of the lunar base are significantly increasing, and stable energy supply for the base being unable to be guaranteed. The system comprises a solar photovoltaic power generation unit, a power management unit, a water storage tank, a water photolysis unit, a hydrogen and oxygen storage unit, a hydrogen-oxygen to water conversion unit, a state monitoring unit, a chemical propulsion unit, an environmental control and life support unit, and a load. The water photolysis unit and the hydrogen-oxygen to water conversion unit can generate hydrogen and oxygen, and the solar photovoltaic power generation unit and the hydrogen-oxygen to water conversion unit can generate electric energy, thereby ensuring stable energy supply for a lunar base.

IPC Classes  ?

• C25B 9/19 - Cells comprising dimensionally-stable non-movable electrodesAssemblies of constructional parts thereof with diaphragms
• C25B 1/04 - Hydrogen or oxygen by electrolysis of water
• C25B 1/55 - Photoelectrolysis
• C25B 9/50 - Cells or assemblies of cells comprising photoelectrodesAssemblies of constructional parts thereof
• C25B 9/65 - Means for supplying currentElectrode connectionsElectric inter-cell connections
• H02J 7/35 - Parallel operation in networks using both storage and other DC sources, e.g. providing buffering with light sensitive cells
• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

The present invention relates to a method for predicting a structural response of a liquid-propellant rocket engine to an impact load. The purpose of the present invention is to solve the technical problem in the prior art of it being difficult to satisfy a multi-source load excitation condition during a complex hot commissioning process due to the fact that the input loads used are all single-acceleration loads. Provided is a method for predicting a structural response of a liquid-propellant rocket engine to an impact load. In the present invention, a dynamic modeling technique for the whole structure of a liquid-propellant rocket engine and a dynamic analysis method for multi-excitation-source impact are combined. On the basis of the whole model of the liquid-propellant rocket engine being rationally simplified, a dynamic analysis of the whole structure of the liquid-propellant rocket engine is conducted by means of applying a forced displacement load at multiple positions to serve as excitation inputs, and the structural strength of key parts of the engine and the swing angle of a swing bearing are analyzed, such that an effective assessment can be provided for engine structure optimization and an ultimate bearing capability, so as to provide an effective estimation of the structural strength of the engine during subsequent commissioning under a high working condition.

IPC Classes  ?

• F02K 9/96 - Rocket-engine plants, i.e. plants carrying both fuel and oxidant thereforControl thereof characterised by specially adapted arrangements for testing or measuring
• G06F 30/15 - Vehicle, aircraft or watercraft design
• G06F 30/17 - Mechanical parametric or variational design
• G01B 11/00 - Measuring arrangements characterised by the use of optical techniques
• G01C 15/00 - Surveying instruments or accessories not provided for in groups

Abstract

A multi-redundancy electromechanical servo system for regulating a liquid rocket engine, comprising a triple-redundancy servo controller (1), a double-redundancy servo driver (2), double-winding electromechanical actuators (4, 5), a triple-redundancy position sensor (6), a thrust regulator (8) and a mixed ratio regulator (9). Engine thrust, a mixed ratio regulation instruction and a feedback signal of the triple-redundancy position sensor are inputted to the triple-redundancy servo controller, and the triple-redundancy servo controller outputs thrust and mixed ratio regulation PWM wave control signals to the double-redundancy servo driver. The double-redundancy servo driver outputs a three-phase variable-frequency variable-amplitude sine wave current to drive the double-winding electromechanical actuators to drive the thrust regulator and the mixed ratio regulator to move, thus achieving engine thrust and mixed ratio regulation. The present servo system has a simple system and excellent control characteristics, has the ability to “control a two-degree fault operation and drive a one-degree fault operation”, and significantly improves the reliability and usage maintainability of the thrust and mixed ratio regulation of the liquid rocket engine. Also disclosed is a method for implementing the foregoing multi-redundancy electromechanical servo system.

IPC Classes  ?

• F02K 9/56 - Control
• F02K 9/60 - Constructional partsDetails not otherwise provided for
• F15B 18/00 - Parallel arrangements of independent servomotor systems
• F02K 9/42 - Rocket-engine plants, i.e. plants carrying both fuel and oxidant thereforControl thereof using liquid or gaseous propellants
• F02K 9/58 - Propellant feed valves
• G06F 11/16 - Error detection or correction of the data by redundancy in hardware
• G05B 9/03 - Safety arrangements electric with multiple-channel loop, i.e. redundant control systems

Abstract

A multi-redundancy electromechanical servo system for regulating a liquid rocket engine, comprising a triple-redundancy servo controller (1), a double-redundancy servo driver (2), double-winding electromechanical actuators (4, 5), a triple-redundancy position sensor (6), a thrust regulator (8) and a mixed ratio regulator (9). Engine thrust, a mixed ratio regulation instruction and a feedback signal of the triple-redundancy position sensor are inputted to the triple-redundancy servo controller, and the triple-redundancy servo controller outputs thrust and mixed ratio regulation PWM wave control signals to the double-redundancy servo driver. The double-redundancy servo driver outputs a three-phase variable-frequency variable-amplitude sine wave current to drive the double-winding electromechanical actuators to drive the thrust regulator and the mixed ratio regulator to move, thus achieving engine thrust and mixed ratio regulation. The present servo system has a simple system and excellent control characteristics, has the ability to "control a two-degree fault operation and drive a one-degree fault operation", and significantly improves the reliability and usage maintainability of the thrust and mixed ratio regulation of the liquid rocket engine. Also disclosed is a method for implementing the foregoing multi-redundancy electromechanical servo system.

IPC Classes  ?

• F02K 9/56 - Control