Papers by Keyword: Aeroengine

Abstract: This paper selects a load-bearing stage of an aeroengine compressor stator as study object to describe the model simplification method. Based on the criterion of cross section equivalence, the stator vanes are simplified into three versions of rectangular beams with variable cross section, using eight sections, four sections, and two sections respectively, to set up finite element model of the structure. Natural frequencies of the three simplified models are calculated and the results are compared with that of the original model. Comparison results show that the largest calculation errors of the first 10 natural frequencies using the three simplified models are-3.22%, -4.97% and-5.38%, respectively, but with this method, the model scale and computing time reduce significantly down to 3-4%, and 1-2% of the original model. The result shows that, the proposed method is applicable to relevant practical engineering.

Abstract: In this paper, the key technique involved in life prediction of aeroengine’s high temperature component for creep and fatigue/creep interaction, namely, the life prediction methods for high temperature component are discussed systematically. The essential thinking、features and development direction of the theories are commented in detail. All the results obtained are valuable to engineering applications.

Abstract: Inspection on chips from oil system is an important method for modern aeroengine condition monitoring. Energy spectrum analysis technique is the most widely used and effective method in inspection on metal chips. In this method, size and quantity of chips are observed by scanning electronic microscope and qualitative and quantitative analysis of element contents are finished by energy dispersive spectrometer. Through above experiments, material type of metal chips can be analyzed and material mark can be determined by comparison with the materials list used in the aeroengine. In this article, characteristics and advantages of energy spectrum analysis technology are systematically introduced and typical appearance feature and energy spectrum curve of common l chips are summarized in engineering practice. In addition, problems and prospects of energy spectrum analysis technique are proposed.

Abstract: Control technology of aeroengine has made remarkable development in recent 20 years. In order to meet the needs of high performance, high precision propulsion system control, based on computer technology, microelectronic technology and control theory, the control technology is from traditional hydraulic mechanical control to digital electronic control. Digital electronic control has been a huge success from limited function to the full authority control and from the development test to practical application. In the future it will have more widely application and development in the field of military and civilian aircraft control. This paper mainly discusses the full authority digital electronic control. It shows that the digital electronic engine control has wide application prospect and high application value.

Abstract: A improved genetic algorithm is proposed based on a new fitness function in allusion to the problem that the traditional genetic algorithm is not fully consider the knowledge of the problem itself.The improved genetic algorithm is used to analyze the fault feature , to extract the fault and remove redundant characteristic parameters for the fault classification and calculation.The diagnosis example shows that the method has faster convergence speed and can be effective for fault identification.

Abstract: With the rapid development of aerospace industries, how to realize the automatic and optimized pipe-routing layout for the aero-engine has become a hot issue to be urgently solved. For the issue, a novel automatic and optimized pipe-routing layout method based on the improved artificial fish swarm algorithm was put forward in this paper. First, the mathematical model of the pipe-routing layout problem was established. Then, in view of the deficiencies of the artificial fish swarm algorithm,chaos mutation was used to carry out easy and rapid searching as well as robust escape from the local optimum,and gradient setting was used to raise the convergence speed and the solving accuracy.Further, the improved artificial fish swarm algorithm was applied to the pipe-routing layout for the aero-engine. At the end, the effectiveness and feasibility of the proposed method was proved by a case study.

Abstract: An exhaust temperature test system is developed for resolving the problem that the exhaust temperature of a certain type aeroengine can not be real time monitored. The exhaust temperature test and temperature compensation circuit are designed and data collecting, processing and displaying program are written in this system which utilizes PC104 built-in industry computer as its core controller. The exhaust temperature of aeroengine can be real time monitored during test-drive by ground guarantee staff, which can help them to judge the condition of the aeroengine.

Abstract: This paper takes the 2^nd HP turbine disc of an aeroengine as research object, construct its finite element model in software-Patran. According to the work environment of 2^nd HP turbine disc, the boundary conditions of stress field analysis and temperature field analysis are confirmed. Based on the finite element theory of thermal analysis and structure analysis, we use finite element software-Nastran to analyze centrifugal stress and thermal stress. Numerical calculation method was used to fit the data and finally we got the thermal elastic stress field. According to the computed results, the life assessment points of disc were confirmed. The static strength of 2^nd HP turbine disc was tested based on the EGD-3 criterion. All the work established the foundation for subsequent life analysis.

Abstract: Stress and fatigue analysis of welded case shell on aeroengine under combined internal pressure and axial loads using elastic-plastic finite element has been performed. The results show that the largest stress concentration appears on the mutational cross section of the fixture seat and fixture fringe structure some distance from the weld toe. The positions with the weakest fatigue life locate at the fixture fringe close to the weld toe of girth joint, and also appear at the ring closed weld of the case shell middle.

Abstract: Aeroengine parameters model is pivotal for development of aeroengine virtual testing system. So the modeling method is discussed in this paper in detail. Firstly, dependency relationships between parameters are established according to the variational character of each parameter in different working state, including transient processes such as false start, cold run, start, acceleration, deceleration, stop and stable processes such as idle, warming, performance test. Then parameter equations are formulated based on least square fit, utilizing actual test data of some kind of turbo-fan aeroengine as prototype. With the method, modeling work for aeroengine virtual testing system is facilitated. And each parameter varying pattern is consistent to that of real aeroengine. Furthermore, different test process can be simulated via changing relevant setting parameters. It makes the development of aeroengine virtual testing system much easier.