Whenever, I mentioned that J-20's Engines, already has 3-D TVC (AVEN) Nozzles installed, I was met with howling laughers, ridicules, and outright disbeliefs, as if this is some exotic technology, that the Chinese will never able to crack, much less, it is already installed on the J-20.
A casual search on Google, with the right Chinese Keywords, for the AVEN technology, pull up numerous technical articles, written by Chinese researchers for their colleagues. Most of those technical articles, were published in Chinese Journals, in the 1990's and early 2000's.
The AVEN technology was first demonstrated in early 1990's by the
F-16 MATV. And it was publicly demonstrated or presented, to the Chinese President, at the
2004 Zhuhai airshow.
This article here was first published, in
2002, in China's Aviation Engine Journal. It described the development process and methodology of how China was able to crack the (
Axis-symmetric Vectoring Engine Nozzle, AVEN) technology. The author was an insider, who worked directly with China's AVEN project.
View attachment 421148
This article was republished,
2008 in this website,
http://ido.3mt.com.cn/Article/200806/show1006412c30p1.html, under the title "
China's F-22 will appear soon: Axis-symmetric Vectoring Engine Nozzle Experiments Exposed."
Somebody,
@Figaro, has claimed that he can understand technical articles translated from Chinese to English by BING's machine translation service. Well, I am going to post the translation here. If he still claim he could understand it, I take my hat off to him.
" F22 will launch in China : plane axisymmetric vectoring exhaust nozzle test exposure !"
1 aircraft vector thrust technology is by changing the exhaust direction more steering torque technology for aircraft.Plane thrust vectoring fighter through application of the technology of ultra mobility, STOL, and low detectability, greatly increase the fighter's combat effectiveness and survivability. Developed countries such as the United States, Russia as an important priority.
Aircraft vector thrust technologyStudy, changing the exhaust direction, namely, thrust-vectoring nozzleResearch is a key and decisive part, you must firstResearch and development. Axisymmetric vectoring exhaust nozzle (AVEN) was developed from conventional mechanical-divergent nozzle of a thrust-vectoring nozzle through the diffuser nozzle deflection change the exhaust direction. The entire aircraft vector thrust technology, AVEN features with a simple, light weight, low-risk, small modifications to the aircraft, engine host requirements, is to implement the best nozzle for thrust vectoring technology programme. AVEN technologyResearch goal is the completion of the target platform development of turbofan AVEN test, and thermal testing
Transfer from; Sina air force Forum
2 Research objectives and approach
AVEN to in keep axisymmetric received spread nozzle area and area than regulation function of based Shang implementation diffusion paragraph of deflection, and other mechanical device of important difference is AVEN is a complex of space more freedom movement mechanical, people most care of is how makes such of mechanical device movement up, how achieved deflection, how guarantee deflection Hou many of, and mutual make stack of component coordination movement and not card delay, how determine right of movement law. SoResearch ideas from capturing movement mechanism of manpower, from computer simulations to model when the model succeeds, immediately decide on the unit converted to I: 1 prototype, thus overcoming the thrust-vectoring nozzleStudy of key technologies--motion mechanism.
As AVENStudy on technical difficulty, lack of domestic technical reserves, no similar mechanism for reference, it is impossible to ascertain the need to address the key. In view of this situation, through self-reliance, step by stepApproach from computer simulations to model, from the model to the physical, from cold to hot, and key technology of phased decomposition, by technical measures, and, if necessary, by computer simulation or test-test methods for authentication, andStudy on the next phase of decomposition technique, and so development, gradually capturing the key stages in the AVEN, finally accomplished the goal platform turbofan AVEN and the test of thermal test.
AⅥ is one of the test piece pneumatic, organization, structure, strength, control, materials and processes, and many other technologiesResearch topics, each have a large number of innovativeResearch, engineering and technical coordination of multiple projects in parallel across both research quality have made great gains.
3 computer simulation
AVEN is a complex mechanism with multiple degrees of freedom motion of space, typical of AVEN mechanism about 200 motion artifacts, more than 300 pairs these components in an annular space overlap movement only by artificial meansStudy of its mechanism and their relationship is impossible. Throughout the AVEN during the test part, using computer simulation technology, complete mechanismResearch, design and Assembly process of movement members checks, and many other technical work not only effectively reduce theResearch cycle, improve the accuracy of structure design.
3. 1 movement mechanism simulation
? AVEN Zi language dynamic simulation software of the main moving components,Study of AVEN mechanism, the main movement of the moving components, A9, diffuser and nozzle of the operating cylinder's position, so as to give position and control law of AVEN.
3 2 simulation
AVENDuring the study, especially full-scale development of cold and hot test, computer simulation technology, in accordance with the following procedure, complete closed-loop design of AVEN:
(1) according to the aerodynamic design and structural design of movement mechanism simulation results;
(2) press agency programme for the true size of the initial 3D computer solid modeling, computer Assembly simulation entities, and AVEN entities by computer simulation, check the reasonableness and accuracy of the movement of the structure;
(3) the principal bearer of strength design of 3D models available to strength and rigidity checking and preliminary structural strength;
(4) was given control, hydraulic system and controller of parallel program design;
(5) the design of closed-loop process, after more or less after a few repeated, structural design optimization, subsequent design after a few repeated, structural design optimization, design has a good foundation. After the completion of engineering design of the main components, according to the 3D simulation of the real structure of AVEN, verify the correctness reasonable structure design of XING and control and inspection of parts assembling technology of processing performance and test performance.
In accordance with the design process can be completed by the hardware processing virtual Assembly and virtual testing, effectively excluding most of the set 10 blind spots and blunders, which greatly improves the quality of the test pieces, shortening the development cycle, saving research funds.
In these simulations based on the preparation of AVEN mechanism design and motion simulation software, can be done quickly and accurately design and optimization of AVEN
4 motion mechanism and model test
Verify the validity of movement mechanism simulation results, and furtherStudy on the AVE. N motion, starting a cold motion mechanism and model for test development and test.
First of all, AVEN diffuser scaled motion mechanism test is completed,Research on motion control performance and coordinating relations of the deflection movement of main members thereafter, Ling State of the actual engine size prototype has been developed,Study of AVEN mechanism, mechanism of structural feasibility and structure of each agency implementation approaches,Study and validation of control and control system. Based on the above two sets of test development and test and verify the validity of movement mechanism simulation results obtained direct and clear understanding of AVEN mechanism; mastered the methods of AVEN; finding optimized vector angle of approach; completed a level, development of semi-automatic controller; determine the next step is to solve the key technical.
5 capturing key technologies and by hot testing-test
Cold testResearch based on L2 demands according to the aircraft sector and technical achievements of previous work, break down the key technology, completed the thermal test and control system design, construction and the apoptosis, realized in platform AB of turbojet engine test. Hot bench test, 8 main technical key is verified, namely aerodynamic performance, structural design, strength and rigidity analysis, automation, materials and processes, cooling and heat insulation, sealing and sealing, testing and commissioning, solutions are successful for AVEN technology demonstrator developed by China laid a solid technical foundation.
6 technical validation and improvement of thermal test
Thermal test has conquered the 8 key techniques on the basis of
To conquer 4 key technology, improved thermal test is developed, completed two phases of testing. 5,580 vector was completion of the first stage of the test cycle, testing showed that the test in complete inherits all the success of two batches at the same time, to capture the four key technology is designed, AVEN indicators have fully reached the Jets 12 requests from departments. Due to the restrictions of the test bench, the AVEN hot testing cannot be comprehensive test, for this reason, the test bed for the adaptation, added to the test of three-component force measuring system. In a three-component force measuring system test bench, to increase improved thermal test vector angles, increase the number of vector cycle testResearch on maximum AfterBurner vector angle of 21 degrees, thermal vector cycles 10,026. Trial run proves AVEN thermal test piece has a certain degree of reliability.
Meanwhile, gets the key components of the temperature and stress distribution and thrust characteristics of test data.
7 hot testing standards of the target platform after the above work has been carefully analyzed, based on three basic pneumatic scheme and optimization of two basic structural analysis identifies the target platform AVEN final programme and the need to overcome the difficulties
Two AVEN AVEN has inherited the former all the technical measures of success. Improved all shortcomings and finally accomplished the goal platform AVEN AB test. AVEN has maintained the target platform and the target platform similar to that of the nozzle aerodynamic characteristics, control and installation interface, good interchangeability. Test results show that target large adjusting range and high load conditions? long teach ˋVEN Kan Chang campaign flexible and accurate, nozzle seal well and the system is reliable and effective and targeted platform
AVEN has brand new small integrated digital control systems, and the safety and reliability of emergency system.
Target platform AVEN meets the following specifications:
(1) deflecting azimuth: 360 degrees;
(2) vector angle: 17 degrees ~20 degrees;
(3) the deflection rate: Wx = 120 degrees ~180 degrees/sec, Wy=Wz=45-60 degrees/s;
(4) the incoming force structure, overall dimension aircraft requirements;
(5) set up emergency control system reset device.
AVEN's test results showed that the target platform:
(1) nozzle adjustment range full engine host requirements.
(2) the incoming force structure to withstand high thrust levels of load
(3) A8 is designed correctly. Using the digital electronic controller
3) A8 design. Original AVEN A8 digital electronic controller automatic control of fully compatible with the original control system, no need to change.
(4) The A8 and A9 can be controlled individually and according to the relationship between a given linkage, coordinate very well.
(5) A9 realizes miniaturization, digitalization, integration of control systems, stable and reliable.
(6) elements, such as seals, adjust work reliably.
(7) AVEN emergency reset functions is safe and reliable
(8) in the engine asked, part small AB, AB and AB, AVE n-deflection nozzle and aerodynamic parameters of hosting matches in the work is good, the mechanical system is stable,
(9) overall dimension and aerodynamic aircraft requirements.
(1O) test measured success in various State vector
Force, the main component of effectiveness of the temperature and stress distributions and engines.
Turbofan axisymmetric vectoring exhaust nozzle test indicates that the hot test measures to solve the 11 key technology is successful, thrust-vectoring nozzleResearch up to a new level.
8 concluding remarks
AVEN to maintain the existing divergent nozzle of the engine all the features, and control the same way to finalize the axial symmetry of the AVEN will replace the existing divergent nozzle, 3 half-plane has a tactical advantage.
Similarly, the AVEN according to push more than 10, pushing more than 12, pushing more than 15 engine requirements for the design, as a push than 10, pushing more than 12 a standard nozzle, push the ratio of 15, our 4th-generation fighter with higher mobility, enhance our national defence air force. Aircraft vector thrust technology can be applied in the shipborne aircraft and are expected to be developed for shipboard dinner STOL aircraft and general layout of vertical take off and landing ship-borne aircraft (General layout of vertical take off and landing of aircraft taking off and landing in a similar way to launch vehicles, mobile landing platform helicopters taking off and landing on the platform or medium ships and landing).
Aero-Engine modified with a thrust-vectoring nozzle, as a new type of ground effect aircraft or ground-effect boat momentum will greatly improve its ability to surprise, mobility and living our?Study on application of new methods, such as computer simulation technology and new materials (Ni3AL)Research and new technologies (such as superplastic forming and diffusion bonding)Research, on the development of national defense technology and civilian technology will play a role in promoting.
First author: Jia Dong, senior engineer, graduated from Northwestern Polytechnical University was born in 1967 ***7 month Afterburner axisymmetric vectoring nozzle of adjustable nozzles, and the development of CADResearch work has received the 2001 Award for technology and innovation of the Communist Youth League and the China Aviation Group, first prize of the 2001 Commission of science and technology and other."
nothing is concrete WS-15/TVC this just showing that China researching on TVC not telling WS-15/TVC combo 
one should go on trying with the Alphabet tool, the google's translate service... 
