Feb 2021, Volume 8 Issue 1
    

  • Select all
  • Topic:The technology of new generation medium-lift launch vehicle
    LM-8: the Pioneer of Long March Rocket Series on the Innovations of Commercialization and Intelligence
    SONG Zhengyu, WU Yitian, XU Shanshu, CHEN Xiaofei, XIAO Yun
    2021, 8(1): 3-16. https://doi.org/10.15982/j.issn.2096-9287.2021.20200009
    Download PDF
    The latest innovations of the Long March 8 (LM-8) launch vehicle is reviewed. The LM-8 launcher fully inherits the achievements of Chinese in-service rockets and the new generation rockets, and focuses on launching satellites to the sun-synchronous orbit (700-1 000 km), taking into account the launch services for LEO and GTO satellites. The LM-8 launcher is available in both combinatorial and integrative configurations for a variety of missions. In order to enhance market competitiveness, a series of innovative practices have been taken, including agile manufacturing, system integration, responsive launch, autonomous and unattended operation, and simplified launch site infrastructure. In response to the future trend of intelligent rockets, the autonomous technologies are explored for LM-8, such as onboard dynamic trajectory planning, active control of take-off drift, and automated launch window correction. It also paves the way for reusable launcher in steps, conducts the demonstration for vertical landing with side and core boosters strapped together, and makes progresses in large-scale light landing mechanism, autonomous guidance method, etc. These innovations eventually build the LM-8 into a new generation of medium rocket with high cost-effective performance, good usability, and high reliability and safety.
  • Topic:The technology of new generation medium-lift launch vehicle
    Integrated Design Technology of Electrical System for the Long March 8 Launch Vehicle
    ZHOU Tao, XU Yang, HU Haifeng, ZHANG Siyan, ZHANG Huanxin
    2021, 8(1): 17-26. https://doi.org/10.15982/j.issn.2096-9287.2021.20200014
    Download PDF
    Integrated design is the main development trend of the spacecraft electrical system. The development status of electrical system in the new generation launch vehicle at home and abroad is reviewed, and the integrated architecture of electrical system based on the redundant system bus and integrated electronic architecture is put forward for the new generation medium Long March 8 (CZ-8) launch vehicle. The integrated design technology of electrical system is introduced from the aspects of system integration, power supply integration, software integration, test integration and telemetry integration. The integrated design technology will be used for the integration of system functions, and also for the breakthrough of the electrical system from traditional sub-system development to cross-system integration. Therefore, the integrated design technology of the electrical system can be used to simplify the test launch process and improve the launch capability, meeting the needs of a new generation of medium launch vehicles with low cost, high reliability, and fast launch.
  • Topic:The technology of new generation medium-lift launch vehicle
    A Self-locking Electro-mechanical Actuation System for Liquid-Propellant Rocket Engine
    JIANG Yang, LAN Tian, ZHENG Qijia, WANG Zhihui, ZHAO Yingxin
    2021, 8(1): 27-33. https://doi.org/10.15982/j.issn.2096-9287.2021.20200006
    Download PDF
    A self-locking electromechanical actuation system to gimbal a high thrust liquid rocket engine is put forward to meet the demands of the batch production and the triplex horizontal preparation for an agile launching of China’s new generation launch vehicles. A self-locking module is designed, a tandem compact electro-mechanical actuator and a control algorithm to suppress structural resonance are adopted. Ground experiments are carried out. It is shown that，the requirements of a long term horizontal transportation, a horizontal testing to tolerate the engine gravity effect, the control of the low frequency resonance of a liquid engine, and easiness for batch production, shall all be satisfied, laying a good foundation to facilitate the development of the next generation medium-sized launch vehicle in China.
  • Topic:The technology of new generation medium-lift launch vehicle
    Digital Manufacturing Technology of Special-shaped Pipe of Launch Vehicle Based on Point Cloud Measurement
    WEI Qiang, LIU Fengcai, SU Zaiwei, LIN Yanlong
    2021, 8(1): 34-41. https://doi.org/10.15982/j.issn.2096-9287.2021.20200011
    Download PDF
    In view of the current manufacturing model of launch vehicle pipe sampling and final assembly, it severely restricts the assembly period of the launch vehicle. In this paper, the use of laser scanning method is proposed to build a physical point cloud model of different arrow body. According to the assemble benchmarks based on different rocket body, the data is extracted from the physical point cloud models of different rocket body to establish the datum plane and datum circle center, using benchmark alignment to realize digital assembly of point cloud models of different arrow body, and using coarse matching, fine matching and other algorithms to analyze the benchmark establishment and benchmark alignment. Based on the assembled point cloud model, according to the "point, line, surface" way to establish the catheter model for subsequent processing. The digital pre-manufacture of the carrier rocket sampling catheter is realized sucessfully.
  • Topic:The technology of new generation medium-lift launch vehicle
    Propellant Flow Characteristics in Tank and Related Impact Analysis During the Vertical Landing Stage
    GA Yongjing, WANG Haosu, ZHANG Qingsong, XU Shanshu, WU Yitian
    2021, 8(1): 42-50. https://doi.org/10.15982/j.issn.2096-9287.2021.20200012
    Download PDF
    Reusable technology is one of the key factors to realize the launch vehicle reusability. It is a hot spot in current research to achieve the sub-stage reusability by vertical landing. During the process of launch vehicle taking-off and vertical landing, the propulsion system is not only required to provide thrust in the ascent, but also to realize the smooth deceleration and control of vertical landing. It is required that the rocket engine shall be improved to possess multiple-start and in-depth thrust regulating capability and also have higher requirements to propellant management. During the vertical landing process, the propellant flow characteristics in tank are greatly affected by the acceleration of the vehicle. If there are some lateral disturbance, the propellant in the tank will move violently due to severe acceleration decrease and may affect the normal operation of the rocket engine. In this paper, the propellant flow behavior during the vertical landing process is investigated with Flow 3D numerical simulation, and the influence of the lateral and axial acceleration on the propellant flow behavior during the engine shutdown process is analyzed. The results show that the sloshing amplitude of the propellant is related to the amplitude of the lateral disturbance when the axial acceleration changes to a certain extent, and the sloshing amplitude of the propellant will be greatly enlarged when axial forces suddenly decrease. It is suggested that in the process of vertical taking-off and landing, the attitude of vehicle should be guaranteed as much as possible to avoid large lateral disturbance.
  • Topic:The technology of new generation medium-lift launch vehicle
    Research on Design and Process Program for Grid Fin of Reusable Rocket
    WANG Chen, ZHANG Hongjian, YAN Wei, ZHANG Xi, SHI Yuhong, GUO Yue, YUAN Han
    2021, 8(1): 51-61. https://doi.org/10.15982/j.issn.2096-9287.2021.20200018
    Download PDF
    Grid fin aerodynamic control mechanism is one of the reusable rocket’s key parts. The design and manufacturing of grid fin is rather complex that coupling multi-specialty and multi-link. Aimed at the requirements of the reusable rocket, key design parameters of grid fins and their influences are presented combined with the grid fin’s geometric features from the aspects of working principle, geometric features, section shape, forward and backward sweep, etc.. Considering the thin-wall complex features of lattice and the requirements of high temperature resistance, several kinds of technological schemes and process program of titanium alloy forming and composite molding which can be used in the manufacturing of grid rudder are studied. From the aspects of design difficulty, process difficulty, product qualification rate, product accuracy and cost constrains, a comparative analysis of the process programs are made. Finally, the principles of grid fin design are proposed, providing a reference for the design of the Long March-8R（CZ-8R） rocket and other reused rockets.
  • Topic:The technology of new generation medium-lift launch vehicle
    Research on Launch Vehicle Reliability Assessment of Small Sample Based on Bayes Theory
    SONG Zhengyu, FANG Zhigeng, HE Wule, SUN Yunke, WANG Zhao, LI Caixia, LIU Sifeng
    2021, 8(1): 62-69. https://doi.org/10.15982/j.issn.2096-9287.2021.20200005
    Download PDF
    Aiming at the advanced technology, high development cost and difficult implementation of reliability appraisal test of LM-8 launch vehicle, a method of reliability assessment of small sample based on Bayesian theory is proposed. According to Bayes theorem, various pre-test information is fully utilized to make up for the deficiency of experimental data. Taking Weibull life model, Exponential life model and Binomial life model as three examples of life different distribution types, corresponding mathematical model and numerical calculation method combining Bayesian theory are discussed. Finally, three different types of equipment in the launch vehicle system are selected for reliability evaluation and the results show that the proposed method can make full use of existing information, of which assessment results are superior to the classical method.
  • Topic:The technology of new generation medium-lift launch vehicle
    Low-cost and Fast Manufacturing Technology for Commercial Liquid Rocket Structure
    YANG Ruisheng, CHEN Youwei, WANG Jingchao, CONG Yan
    2021, 8(1): 70-79. https://doi.org/10.15982/j.issn.2096-9287.2021.20200008
    Download PDF
    With the gradual opening up and rapid development of the space launch application market, commercialization is an inevitable trend of the development of the launch vehicle. The rocket structure system is complex and involves a lot of manufacturing technology, which is an important factor restricting the production efficiency and cost of the rocket. How to realize the low cost and fast manufacturing of the rocket body structure has become an important research direction in the development of commercial aerospace. In this context, the application of manufacturing technology of key structural parts of liquid launch vehicle rocket body is systematically summarized, and the development direction of the commercial vehicle structure system is proposed, combined with the development of the LM-8 launch vehicle. The application of low cost and quick manufacturing technology of rocket structure is explored based on the integration of design and process, effectively improving the structure of the arrow product quality and production efficiency.
  • Article
    Introduction of Space Exploration Progress for Planetary Radio Burst Emission
    PING Jinsong, WANG Mingyuan, ZHANG Mo, CHEN Linjie, DONG Liang, WU Yuxiang
    2021, 8(1): 80-91. https://doi.org/10.15982/j.issn.2096-9287.2021.20200016
    Download PDF
    At low frequency electron-magnetic wave band, planetary bodies not only emit thermal radiation, but also emit non-thermal radiation burst. The typical emission is planetary auroral radio burst consists of planetary kilometric wave burst, Jovian radiation at hectometer and decameter wavelengths. This kind of burst has been observed on the ground and in the space for dozens of years. The developed method can also be used as remote sensing tool to detect the inner structure of Jovian magnetosphere. However, the characteristics and mechanism have not been fully understood for the solar system planetary radio burst, there are still quite a lot of open questions left. Similar radio burst may also be observed from the exoplanetary systems. Following the development of space technology, radio astronomical observation has extended to kilometer wave. In the future the large radio array at low frequency can play key role to uncover the mechanism for the planetary radio burst, and also can be used to detect the exoplanets. The Chang’e-4 lunar mission with its low frequency payloads is working as pathfinder for the Earth Auroral Kilometer Radiation (AKR) and Jovian bursts,
  • Article
    Research Advances of Solar Radio Type Ⅲ Bursts at Space Very Low Frequencies
    TAN Baolin, TAN Chengming, HUANG Jing, CHEN Linjie
    2021, 8(1): 92-99. https://doi.org/10.15982/j.issn.2096-9287.2021.20190227002
    Download PDF
    Solar non-thermal high-energy particle flows are one of the main triggering sources of the disastrous space weather events. Their main observational manifestation is radio Type Ⅲ bursts with fast frequency drifting rate. This work introduces the main advances of observational instruments and scientific researches on the solar radio Type Ⅲ bursts at the space very low frequency (< 30 MHz SVLF) in the world, including the space-based or lunar-based solar SVLF spectral polarimeters with high temporal and spectral resolutions. We also discuss carefully the existing problems on the solar radio observations and related researches, also including the main scientific aims and prospective of the space-based or lunar-based solar SVLF observations.
  • Article
    Study of Very Low Frequency Solar Radio Emission Detection with Space Vector Antenna
    CHEN Linjie, YAN Yihua, TAN Baolin
    2021, 8(1): 100-108. https://doi.org/10.15982/j.issn.2096-9287.2021.20190411002
    Download PDF
    Solar winds，Coronal Mass Ejections（CME），interplanetary shock waves and high-energy particle events，induced by the solar radio bursts，are called as solar electromagnetic storms. The propagation，acceleration，and evolution of the CMEs，solar winds，interplanetary shock waves and high-energy particle phenomena mainly happen at the frequency range from tens of kHz to tens of MHz，which is generally considered as the frequency band of Very Low Frequency（VLF）. Though，there are already few space instruments that have investigated the VLF solar radio emissions，most of the observations are spectral measurements，and only occupied part of the whole VLF band，while the imaging observations of the VLF solar radio bursts are still blank. Based on the characteristics of the vector antenna，it can estimate the Direction Of Arrival（DOA）of the incoming waves，which can be used to locate and image the solar radio bursts（Type Ⅱ&Ⅲ）. So all the latest space VLF radio instruments adopt the tripole antenna can do the observations. In this paper，in order to investigate the detection of the solar radio bursts with the space VLF radio explorer，different algorithms are proposed to detect the solar radio bursts with a tripole vector antenna，and simulations have been done with some space VLF radio observations for these algorithms under different conditions. The simulation results show that the vector antenna can locate the radio bursts with a degree-level accuracy. The capability of detecting the solar radio bursts is also analyzed in further for the space VLF radio explorer.