bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mission analysis and design of launch vehicle based on MBSE
Authors: Zhang Longxi , Guo Xiang , Ren Zhengfei , Ma Xiao 
Published: May 2024

Abstract
A reusable launch vehicle is the basis for carrying out large-scale space activities and reducing the cost of space entry. It will greatly enhance the ability to enter space independently and come up with higher requirements for mission planning, demonstration, overall design, and system development of launch vehicles. Based on the model-based system engineering (MBSE) method, the forward process of model-based launch vehicle mission analysis and design is proposed first. Then, taking a launch vehicle as an example, the mission analysis and design are carried out, the mission is defined, the stakeholder requirements and mission requirements are identified, the mission application scenario is analyzed, the mission architecture is built, and the mission requirements model is established. Finally, by establishing the traceability relationship of mission requirements, the forward process of launch vehicle mission analysis is preliminarily realized, and the feasibility of the process is verified. It is of great engineering significance to improve the efficiency of launch vehicle mission analysis and system design.
LPT rotor speed after low-pressure shaft failure
Authors: Meng Xianghai , Wang Chengen , Yu Naijiang , Wei Yumin 
Published: May 2024

Abstract
When designing engine safety and compliance with airworthiness regulations, it is important to determine the variation of rotor rotational speed and other parameters of aero-engine under shaft failure scenarios. In this paper, a transient process simulation model is established using the component method for a high bypass ratio two-shaft direct-drive turbofan engine. It helps analyze the response of engine rotor speed and key temperature parameters after the failure of the low-pressure shaft, the influence of the fuel supply, low-pressure turbine efficiency, and rotor resistance torque on the response of the parameters. The results demonstrate that the sudden increase of the low-pressure shaft speed at the turbine end after the failure of the low-pressure shaft is the most important factor affecting the engine safety design. The fuel supply, LPT efficiency, and resistance torque have significant effects on this sudden increase in speed.
Measurement uncertainty of vertical combustion test of civil aircraft interior materials
Authors: Wu Shuang 
Published: May 2024

Abstract
The civil cabin interior materials vertical combustion test is the necessary test to verify the flame retardancy ability of the floor coverings, textiles, seat cushions and cushions. It is an inspection step required for cabin interior materials before installation, which is of great significance for the safe flight of civil aircraft. During the experiment process, variable factors such as personnel and equipment are highly likely to impact the test results. To ensure the reliability of test results, it is necessary to summarize and evaluate the factors that may affect the results of the test process. Thus, in this paper, the test method, measurement model, and sources of measurement uncertainty have been analysed, and the calculation case of experimental measurement uncertainty has been introduced.
An experimental study on gas-solid two-phase rotating detonation ramjet engine based on aluminum powder fuel
Authors: Jing Jianing , Ma Hu 
Published: May 2024

Abstract
In order to explore the feasibility of solid powder detonation technology, the ground direct connection test of aluminum powder/hydrogen/air fuel detonation engine was carried out in this paper. The experimental results show that hydrogen is needed to achieve detonation combustion of aluminum powder with a diameter of 1 μm. A series of tests were carried out in the range of equivalence ratio of 0.8-1.2. With the increase of equivalence ratio, the mean value of steady pressure, average peak pressure, and average wave velocity of rotating detonation combustion increased first and then decreased gradually, and reached the maximum at the equivalence ratio of 0.9. The maximum propagation frequency of the detonation wave is 2653 Hz, and the average wave velocity is 1667 m/s.
Analysis of the correction process for the initial field iteration calculation of the stability analysis program
Authors: Wang Ruilin , Li Chuanpeng 
Published: May 2024

Abstract
As the heart of aircraft, the performance requirements of aviation engines are increasing, and analyzing the aerodynamic stability of engines has become an essential part. The methods for analyzing the stability boundary of engines at home and abroad are also gradually improving. When using a domestic engine stability analysis program, it was found that the turbine drop pressure ratio changed during the calculation process, which was inconsistent with the initial given. This article focuses on this issue and analyzes the process of parameter correction during the calculation process by analyzing the parameter changes discovered during its use. This program ensures power balance and duct and bypass outlet static pressure balance. The calculation accuracy is improved through these correction processes.
A novel method based on the calculus of variations to optimize the cooling passage configuration in thermal protection structure
Authors: Li Xuan , Wu Shujie , Zhang Qun , Li Xin , Chen Shiqiang 
Published: May 2024

Abstract
A novel method based on the calculus of variations to obtain the optimization of cooling structure was developed in this work. The optimization of heat sink designs for better heat-dissipating effects has been researched substantially. However, the optimization of cooling passage configurations in thermal protection structures to improve the comprehensive heat transfer performance has remained a long-term interest and unsolved problem for researchers. Due to the intrinsic complexity, the laminar flow is usually considered before while the turbulent flow is seldom treated. It is valuable to provide timely and effective solutions to optimize the cooling structure, where the turbulent flow is involved, for practical use. A novel method to optimize cooling structure based on the calculus of variations has been developed to meet this need. The average temperature, temperature inhomogeneity, and coolant flow pressure drop were chosen as objective functions. The cooling channels can be established depending on the geometric and thermal boundary conditions of the structure, and then the quasi-three-dimensional simulation of the fluid/solid coupling field was calculated to get the temperature distribution of the cooling structure, the pressure drop, etc. Hence, this work explores the feasibility of combining coupled heat transfer and the calculus of variations to realize optimal cooling channels. By the novel method, the minimum objective function can be obtained.
Numerical simulation of the water landing process of a light civil helicopter in level 5 sea conditions
Authors: Zhu Yuanchun , Sun Libing 
Published: May 2024

Abstract
A helicopter emergency flotation system can provide flotation capability after the helicopter accidentally falls into the water. To solve the problem of attitude change of a helicopter after landing in water, a numerical simulation was carried out on a light civil helicopter with a weight of 3.5 t. It was simulated in level 5 sea conditions, the traveling speed was 15.4 m/s, and the height of the lowest point of the hydrostatic helicopter from the water surface was 250-260 mm, with or without lift, with or without floats. Landing on the water can be done with either basic or elliptical floats and in three different postures. The simulation results show that equipping a helicopter with pontoons can significantly improve its overturning resistance and flotation capabilities, but the impact on a helicopter equipped with pontoons will increase. Landing a helicopter in the water at a certain elevation angle is beneficial to the stability of the helicopter. A helicopter with a basic pontoon is more stable when it lands in the water. The performance is higher than that of the ellipsoidal pontoon, but the pitch stability of the basic pontoon is lower than that of the ellipsoidal pontoon.
Study on aero engine thermal performance analysis using a new mathematical model of isentropic expansion (compression) process
Authors: Haifei Zheng , Xiqiao Yu , Hao Tang 
Published: May 2024

Abstract
At present, for the research of aero engine performance, it is necessary to calculate the overall thermal performance of the aero engine at the beginning of the research. For the mathematical model of the isentropic expansion (compression) process, most researchers use the ideal state value to calculate in the mathematical model, so that the calculated results have a certain error compared with the actual value. Therefore, the new isentropic expansion (compression) process mathematical model based on the Φ function is applied in this paper to the technical aero engine overall thermal performance calculation. After calculation and analysis, it is concluded that the calculation accuracy of the mathematical model provided in this paper is higher than that of the literature program for the overall thermodynamic performance parameters of the aero engine, whether it is the thrust of the aero engine, the unit fuel efficiency, or the thermal efficiency of the aero engine. It shows that it is feasible to revise and improve the mathematical model of isentropic compression and isentropic expansion process in this paper, more accurate calculation results can be obtained by using the new model in the performance analysis program, and more accurate numerical analysis can be carried out.
Design and thermal protection performance analysis of insulated wing storage box for hypersonic variable-sweep aircraft
Authors: Dai Shuhao , Ji Hongli , Tao Chongcong , Zhang Chao , Qiu Jinhao 
Published: May 2024

Abstract
Utilizing variable-sweep wing technology can further enhance the flight performance of hypersonic aircraft in a wide range of high-altitude, high-speed environments. Existing research on hypersonic variable-sweep flying wings has mainly focused on aerodynamic shape design, with limited research on the internal thermal protection of the aircraft. This study firstly investigates the performance improvement of a hypersonic flying wing using variable-sweep technology through CFD simulations. Secondly, to address the high-temperature issues induced by variable-sweep wings, an insulated wing storage box with a corrugated structure is designed, incorporating a thermal insulation layer made of corrugated webs and insulating materials. Heat transfer simulations are conducted by applying thermal loads to the wing storage box to study the temperature distribution during the variable-sweep process. Finally, a comparison between the corrugated structure design and the non-corrugated structure design of the wing storage box is performed to analyze the thermal insulation performance of the insulation layer. The results show that the heated area of the wing storage box is primarily influenced by the wing’s sweep angle, and the corrugated thermal insulation layer can effectively reduce heat transfer efficiency, resulting in a 30% reduction in the external temperature of the wing storage box.
Numerical simulation of supersonic combustion chemical reactions based on multi-GPUs
Authors: Lai Jianqi , Lu Fengshun , Hu Xingzhi , Hou Lin , Wang Zhiren , Jiang Xiong 
Published: May 2024

Abstract
To achieve a large-scale and efficient numerical solution to supersonic combustion chemical reaction problems, a numerical simulation algorithm for combustion chemical reactions was established on a graphics processing unit (GPU). Numerical simulation of the combustion chemical reaction of a hydrocarbon fuel/air mixture in a supersonic combustor was conducted to verify the accuracy of GPU parallel calculation results and analyze its parallel performance. Numerical results show that GPU parallel computing can accurately simulate the complex flowfield in the combustor. The distribution law of wall pressure is basically consistent with the experimental values, and the numerical agreement is good, indicating that the numerical simulation algorithm for the multi-GPU supersonic combustion chemical reaction established in this paper is correct and reliable. On the Tesla V100 GPU parallel computing platform, the speedup of GPU parallel computing can reach over 100 times, greatly improving computational efficiency. When the grid size is 18.64 million, the parallel efficiency of single and double precision floating-point operations on four GPUs is 66.2% and 69.1%, respectively, which demonstrates that the multi-GPU parallel algorithm has good scalability.
A time-fuel hybrid optimal guidance for micro/nano satellite’s glideslope approach
Authors: Zeng Nengwei , Xu Gen , Chen Danhe , Liu Xingchuan , Lu Zhengliang 
Published: May 2024

Abstract
Aimed at the trajectory planning problem of micro/nano satellites’ approaching missions under multiple constraints, this paper proposes a V-bar glideslope maneuver optimization method considering both time and fuel consumption. A dual-objective trajectory optimization model is established based on the CW motion equation, considering the constraints of trajectory and impulse. The optimal solution set of the glideslope point position and maneuvering time is obtained by employing the NSGA2 algorithm. In order to reduce computational complexity, a method for simplifying trajectory optimization is proposed. By solving a constrained dual-impulse optimization problem, the feasible range of distance and transfer time between adjacent glideslope points are obtained, which transforms the constraint equations of the glideslope maneuver optimization into the search space of optimization variables. The problem is simplified to an unconstrained optimization problem. Finally, a simulation is conducted with the approaching mission of a typical micro/nano satellite. The results demonstrate that the proposed method can provide an optimal solution set considering both fuel and time consumption, offering a flexible maneuver planning strategy for on-orbit application.
Experimental research on the atomization of transverse liquid jet
Authors: Fu Benshuai , Lu Bingju , Xiao Haiyan , Qin Liping , Li Guanghua 
Published: May 2024

Abstract
The transverse liquid jet is widely used in gas-steam ejection, scramjet engines, and other engineering applications. The research of transverse liquid jets can provide a basis for product design and has a wide range of engineering application value. A high-temperature and high-pressure jet experimental system was designed according to the characteristics of the cooling water jet atomization in the gas-steam ejection power system. The high-speed photography method was used to obtain the macroscopic structural characteristics of the transverse liquid jet. In this paper, experimental research of liquid jets under three conditions was carried out. The trajectory curve of the liquid jet considering momentum ratio and temperature is as follows: y/dj
= 2.782q
0.422(x/dj
)0.307(T/T0
)-0.785. It can provide theoretical support for improving the efficiency of gas-liquid mixing in power systems, engines, etc.
Analysis of landing gear simplified modeling and simulation based on amesim
Authors: Jia Junjie , Li Wei , Li Shengjun , Zhu Zhenshan , Ren Fang , Xie Yan 
Published: May 2024

Abstract
Aiming at the theoretical research of aircraft take-off and landing taxiing control characteristics and real-time interactive application scenarios, the simplified model modeling method of landing gear is studied. Through the reasonable simplification hypothesis of the landing gear pillar, a benchmarked, general, and pillar-type simplified model of the landing gear is formed. In the process of ground motion, based on the force analysis of aircraft taxiing, a six-degree-of-freedom mathematical model of ground taxiing is established. Based on the Amesim six-degree-of-freedom model, the aircraft is built, and the simulation test of aircraft taxiing turning and landing brake is carried out in combination with the simplified take-off and landing model. The results show that the general benchmarked pillar landing gear model formed in this paper is reasonable and feasible, and can quickly construct the aircraft landing gear model, which is convenient for subsequent optimization and design.
Fluid-solid-ablation coupled calculation of hypersonic vehicle based on rbf grid deformation method
Authors: Yang Fan , Dai Gang , Zhao Wenwen , Chen Lihua 
Published: May 2024

Abstract
The ablative phenomenon of the thermal protection system happens when the hypersonic vehicle suffers serious challenges of aerothermal due to high Mach number. To determine whether the thermal protection system is destroyed, the fluid-solid-ablation loosely coupled method for Carbon-Carbon composite materials is proposed to calculate the deformation of ablation and acquire the deformed shape. Navier-Stokes equation, heat conduction equation, and linear ablation model are applied to calculate the fluid field, the solid field, and the ablation receding amount. As one of the most widely applicable dynamic mesh methods, the Radial Basis Functions (RBF) dynamic method is used to get the deformed solid mesh. The ablation of a missile is computed and analyzed. It could be found that the surface temperature of the head increases during flight and the ablation of the surface results in the change of the vehicle’s shape. The ablative layer thickness of the thermal protection system should be greater than the max ablative deformation, reaching 4.4 mm of the missile. The proposed fluid-solid coupling method could effectively predict the ablation deformation of the vehicle and guide the design of hypersonic vehicle thermal protection systems.
Aircraft maintainability verification evaluation based on fuzzy analytic hierarchy process
Authors: Chen Xingxing , Feng Mingyu , Zhao Rujuan 
Published: May 2024

Abstract
This paper uses the fuzzy analytic hierarchy process to establish the mathematical model of aircraft maintainability verification in the flight test stage. The maintainability evaluation index system is constructed from the factors that affect the aircraft maintainability level, such as equipment layout and accessibility, cover design, marking and error prevention, standardization and interchangeability, and human factor engineering. Through case analysis, the application of this method in the maintainability verification of the military aircraft flight test phase is introduced.
Research on rapid batch test technology of small satellite attitude and orbit control system
Authors: Zhang Shaopo , Li Yongqiang , Dai Jianfeng , Wu Zhijing , Chen Ye 
Published: May 2024

Abstract
The attitude and orbit control sub-system of small satellites is an important sub-system to ensure the stable operation of satellites in orbit, and its testing in the satellite factory development stage runs through the whole testing process. Most of the traditional attitude and orbit control sub-system tests require the cooperation of many people to complete the performance tests of various components and sensitive devices, which also leads to the complicated and time-consuming testing process of the sub-system. At present, the mass production of small satellites is developing rapidly. In order to meet the urgent needs of small satellite mass production, the traditional attitude control subsystem test equipment and methods can’t meet the requirements of satellite mass production mode. In order to meet the needs of small satellite mass development, this paper studies the rapid batch test technology of small satellite attitude and orbit control systems. A fast pipeline test system which can support the performance and dynamics simulation of various components of a multi-satellite attitude and orbit control subsystem is studied. Based on the architecture of real-time communication between the upper computer and lower computer, the system can realize the integration and rapid testing of component performance and dynamic simulation. A continuous dynamic simulation test of 2140 seconds was carried out for the cruise mode and attitude maneuver mode of a certain type of satellite in orbit. During the test, various components and sensors of the attitude and orbit control subsystem operate correctly and can support the stable operation of the required attitude in various modes of the satellite, which can verify the correctness of the interface and performance of the satellite attitude and orbit control subsystem. The research results greatly reduce the input of manpower and material resources, and greatly improve the test efficiency. It lays a foundation for the rapid batch test of the small satellite attitude control subsystem.
A model-based control strategy for turbo-shaft engine
Authors: Xin Changkun , She Yunfeng , Xing Yaoren , Meng Sheng 
Published: May 2024

Abstract
This paper takes the turbo-shaft engine (the power source of the helicopter) as the research object, and mainly conducts the simulation of its related control law and control structure. The working principle of the turbo-shaft engine is briefly introduced initially, and then the component-level model of the turbo-shaft engine is established. This paper focuses on the design of the control law upon the turbo-shaft engine, and verifies the designed control law through the results of simulation by MATLAB/Simulink. Finally, the relevant data collected from 240KW hybrid system is taken into the consideration to verify the control algorithm. The results show that the control accuracy of the corresponding control algorithm in this paper is high (accuracy≤5%).
The active disturbance rejection control method for small-scale turbojet engine
Authors: Wang Nan , Xu Jianguo , Li Zixing 
Published: May 2024

Abstract
To enhance the disturbance resistance of the control system for a small-scale turbojet engine, research has been conducted on the active disturbance rejection control (ADRC) method. With gas generator speed N
g as the control parameter, an ADRC control scheme was established. Tracking Differentiator (TD), Nonlinear State Error Feedback (NLSEF), and Extended State Observer (ESO) were analyzed in detail, and their parameters were designed. The ADRC method was compared with the Expert PID control method through simulation experiments. The results show that ADRC has a small overshoot and strong disturbance rejection capabilities, allowing for a faster recovery to a steady state when disturbances occur.
A novel unloading strategy for solar sails using reflectivity control device
Authors: Qi Xuanchi , Fan Caizhi , He Guanwei 
Published: May 2024

Abstract
For near-Earth spacecraft, many environmental forces are utilized to unload reaction wheels. However, effects like magnetic force or atmospheric friction hardly exist in deep-space environments where solar sails operate. Thus, this paper proposes an unloading method that uses reflectivity control devices to generate Solar Radiation Pressure (SRP) torque to conduct the unloading process of solar sails operating in deep space. Firstly, the basic principles of the Reflectivity Control Device (RCD), satellite kinetic model, and Pulse Width Pulse Frequency (PWPF) modulator are given. Secondly, based on the torque envelope obtained by traversing all switch combinations of RCD, a novel strategy using a PWPF modulator is specially designed to achieve efficient unloading. In the end, we carry out numerical simulations and analyze the influence of different parameters, through which the validity of the proposed torque resolution scheme is demonstrated.