Trajectory Planning for Landing Phase of Reusable Rocket with High Thrust-to-Weight Ratio

2021 ◽  
pp. 5311-5323
Author(s):  
Cong Wang ◽  
Zhengyu Song ◽  
Guoxing Shi ◽  
Qinghai Gong
Keyword(s):  
Trajectory Planning ◽  
Weight Ratio ◽  
High Thrust

Design Aspects of Power Plants for V/STOL Aircraft

1967 ◽  
Author(s):  
J. F. Coplin
Keyword(s):  
Power Plants ◽  
Weight Ratio ◽  
Gas Generator ◽  
Extensive Experience ◽  
Thrust Vectoring ◽  
Two Generations ◽  
High Integrity ◽  
Integrated Concept ◽  
High Thrust ◽  
Efflux Velocity

Thrust in execess of that required for cruise and flight maneuvering is necessary to provide an aircraft with a VTOL capability. The extra thrust may be obtained by enlarged cruise engines with thrust vectoring or by retaining the optimum-size cruise engine possibly with thrust vectoring and adding a lift power plant in the form of lift jets or lift fans. A brief outline of extensive experience with lift jets, thrust vectoring, and lift fans is given and the importance of this background in making it possible to design more advanced engines which will satisfactorily meet practical operational requirements is brought out. Experience in two generations of lift-jet flight testing has shown many important areas where specal features must be incorporated in the design from the beginning to achieve high thrust for a compact volume, light weight, and high integrity in the relatively severe environment in which the lift jet has to operate. Examples are cited. The relative importance of thrust/volume and thrust/weight ratio is shown with reference to VTOL strike and transport aircraft. An integrated concept, using compact lift jets for VTOL strike aircraft and compact low-efflux-velocity lift fans using the same engine as a gas generator, is briefly noted.

A novel high thrust–weight ratio linear ultrasonic motor driven by single–phase signal

2018 ◽  
Vol 89 (8) ◽  
pp. 085001 ◽  
Author(s):  
Pingqing Fan ◽  
Xuecheng Shu ◽  
Tao Yuan ◽  
Chaodong Li
Keyword(s):  
Single Phase ◽  
Weight Ratio ◽  
Ultrasonic Motor ◽  
Linear Ultrasonic Motor ◽  
Phase Signal ◽  
High Thrust

Research on a high thrust-to-weight ratio small turbofan engine

1995 ◽  
Author(s):  
Iwao Kashikawa ◽  
Masahiro Akagi ◽  
Satoshi Yashima ◽  
Masataka Ikeyama
Keyword(s):  
Weight Ratio ◽  
Turbofan Engine ◽  
High Thrust

scholarly journals Research of a High Thrust-to-Weight Ratio Small Turbofan Engine

1997 ◽  
Author(s):  
Masahiro Akagi ◽  
Masashi Shinomiya ◽  
Junichi Sakaki ◽  
Shunji Sugai
Keyword(s):  
Research And Development ◽  
Weight Ratio ◽  
Development Program ◽  
Engine Test ◽  
Test Results ◽  
Design Development ◽  
Turbofan Engine ◽  
Technical Research ◽  
Supersonic Aircraft ◽  
High Thrust

The 3rd Research Center of the Technical Research and Development Institute (TRDI) of Japan Defense Agency (JDA) and Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) developed and tested the demonstrator of a high thrust-to-weight ratio small turbofan engine with an afterburner called “XF3-400”, the purpose of which is to establish engine technologies for the future supersonic aircraft for JDA. The development program started in 1981 and the first engine test was carried out in 1992. All the engine tests planned completed in March 1995 successfully. This paper reports the design, development and test results of the XF3-400 engine above.

scholarly journals Preliminary Research on a High Thrust-to-Weight Ratio of Double-Sided Composite Impeller Microturbine Engine

2021 ◽  
Vol 2021 ◽  
pp. 1-27
Author(s):  
Cheng Zhang ◽  
Bei Yang ◽  
Yun Wang ◽  
Gaoxing Tu
Keyword(s):  
Power Density ◽  
Design Principle ◽  
Low Cost ◽  
Weight Ratio ◽  
High Energy ◽  
Performance Parameters ◽  
Jet Engine ◽  
Preliminary Research ◽  
Long Endurance ◽  
High Thrust

In some situations, the improvement of the thrust-to-weight ratio (TWR) of microturbine engines (MTEs) for energy-, economic-, and environment-related reasons can be achieved for military or civilian purposes. However, due to limitations of existing traditional MTE technology, it is difficult to meet the key requirements of small aircraft for high energy/power density and low-cost power, especially for long-endurance drone swarms. To address these problems, a novel compact concept of a high-TWR of MTE with a double-sided composite impeller (DSCI) is proposed in this research. First, the principle and structure of the concept are explained through theoretical analysis, and its potential advantages are discussed. Second, the DSCI is analyzed at the top level, and the design principle and important parameters are discussed. The DSCI and supporting jet engine are preliminarily designed. Then, their weight is estimated. Finally, theoretical analytical and numerical simulations are used to preliminarily research the performance parameters of DSCI jet engine at the design point, and the parameters are discussed. These calculations showed encouraging results, with all components of the DSCI jet engine meeting matching characteristics. Compared to the JetCat P500-PRO-GH, the DSCI jet engine has a 39.4% increase in TWR and a 36.82% decrease in specific fuel consumption (sfc). This study lays a foundation for the development of high energy/power density MTEs in the future.

The Effects of Shape Reconfiguration on Morphing Aircraft in Perching Maneuvers

2008 ◽  
Author(s):  
Adam M. Wickenheiser ◽  
Ephrahim Garcia
Keyword(s):  
Disturbance Rejection ◽  
Weight Ratio ◽  
Landing Site ◽  
Dynamic Stall ◽  
Vehicle Model ◽  
Landing Point ◽  
Morphing Aircraft ◽  
Aerodynamic Model ◽  
Attached Flow ◽  
High Thrust

This paper focuses on a novel morphing aircraft capability called perching: the ability of an aircraft to make a planted landing using primarily aerodynamic forces in lieu of high thrust. Specifically, the modeling of the perching aircraft’s aerodynamics and the problem of computing and optimizing a perching trajectory using this model are presented. The aerodynamic model discussed herein is designed using empirical and analytical methods in both separated and attached flow regimes, including nonlinear and time-varying effects such as flow separation and dynamic stall. This vehicle model is used to optimize the landing trajectory with respect to its spatial boundaries; these include the maximum undershoot — or dip below the landing point — and the required starting distance from the landing site. Optimal solutions of varying thrust-to-weight ratio and center of gravity location are compared. Additionally, perching trajectories that compare stalled versus un-stalled and morphing versus fixed-configuration aircraft are presented in order to demonstrate the effects of relaxed constraints on flight envelope and shape reconfiguration, respectively. The available control for disturbance rejection is distinguished between morphing and fixed-configuration aircraft. These results show that vehicle morphing increases the controllability of the aircraft throughout the maneuver as well as decreases the spatial requirements of the optimal perching trajectory.

Research of an Advanced Turbine Disk for High Thrust-Weight Ratio Engine

2014 ◽  
Author(s):  
Xiuli Shen ◽  
Shaojing Dong ◽  
Zhiying Chen
Keyword(s):  
Topology Optimization ◽  
Three Dimensional ◽  
Weight Ratio ◽  
Optimization Method ◽  
Turbine Disk ◽  
Welding Residual Stress ◽  
Structural Topology ◽  
Element Analysis ◽  
Calculation Results ◽  
High Thrust

To meet the design requirements of the high thrust-weight ratio engine, the twin-web turbine disk is systematically investigated. The structural topology optimization is carried out with the evolutionary structural optimization method based on the conventional turbine disk, and a new shape of the twin-web turbine disk is presented. It is similar to the existing ones but with significant improvement for the strengthened ring is not needed. Then the finite element analysis and size optimization are conducted according to the results of topology optimization. The weight of the twin-web disk is reduced by 23.6% compared to the conventional design with the same stress level. Then a preliminary analysis of the welding residual stress is performed. Finally, a rotating three-dimensional photoelastic test is carried out to verify the rationality of the design and the accuracy of the calculation results.

Precipitation in Al-Li-Zr alloys

1992 ◽  
Vol 50 (1) ◽  
pp. 186-187
Author(s):  
D.M. Vanderwalker
Keyword(s):  
Fracture Toughness ◽  
Precipitation Hardening ◽  
Weight Ratio ◽  
High Strength ◽  
Transmission Electron ◽  
Water Quench ◽  
Aluminum Lithium ◽  
Aluminum Lithium Alloys ◽  
Lithium Alloys ◽  
Zr Alloys

Aluminum-lithium alloys have a low density and high strength to weight ratio. They are being developed for the aerospace industry.The high strength of Al-Li can be attributed to precipitation hardening. Unfortunately when aged, Al-Li aquires a low ductility and fracture toughness. The precipitate in Al-Li is part of a sequence SSSS → Al3Li → AlLi A description of the phases may be found in reference 1 . This paper is primarily concerned with the Al3Li phase. The addition of Zr to Al-Li is being explored to find the optimum in properties. Zirconium improves fracture toughness and inhibits recrystallization. This study is a comparision between two Al-Li-Zr alloys differing in Zr concentration.Al-2.99Li-0.17Zr(alloy A) and Al-2.99Li-0.67Zr (alloy B) were solutionized for one hour at 500oc followed by a water quench. The specimens were then aged at 150°C for 16 or 40 hours. The foils were punched into 3mm discs. The specimens were electropolished with a 1/3 nitric acid 2/3 methanol solution. The transmission electron microscopy was conducted on the JEM 200CX microscope.

Precipitate coarsening during hot-compression testing of NiAl + 2 at.% Nb

1986 ◽  
Vol 44 ◽  
pp. 598-599
Author(s):  
W. M. Sherman ◽  
K. M. Vedula
Keyword(s):  
High Temperature ◽  
Flow Stress ◽  
Weight Ratio ◽  
Constant Strain Rate ◽  
Hot Compression ◽  
Compression Testing ◽  
Second Phase ◽  
Precipitate Coarsening ◽  
High Temperature Mechanical Properties ◽  
Ordered Intermetallic

The strength to weight ratio and oxidation resistance of NiAl make this ordered intermetallic, with some modifications, an attractive candidate to compete with many superalloys for high temperature applications. Recent studies have shown that the inherent brittleness of many polycrystalline intermetallics can be overcome by micro and macroalloying. It has also been found that the high temperature mechanical properties of NiAl can be enhanced through the addition of Nb by powder metallurgical techniques forming a dispersed second phase through interdiffusion in a polycrystalline matrix. A drop in the flow stress is observed however in a NiAl-2 at.% Nb alloy after 0.2 % strain during constant strain rate hot compression testing at 1025°C. The object of this investigation was to identify the second phase and to determine the cause of the flow stress drop.

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