Technology of CAD of aviation engine lamina is summed up

Time:2023-06-14 12:09:44
Click:84
source:MCGUFFIE CNC Machining

Aviation engine is a plane " heart " . Technology of aviation engine development is sophisticated, investment is huge, cycle is long. Industry of motor of each country aviation designs technology, material in breakthrough aviation engine science and technology and production technology while, use CAD technology extensively, advance the informatization of the product energetically. Aviation engine lamina is aviation the crucial part in engine of turbine burning gas, among them high-pressured turbine lamina is to be known as more " the bright phearl on imperial crown of modern manufacturing industry " , not only because its are individual the value of on the product 10 thousand dollars, more because its reflected each performance centrally,design the contradiction between the requirement. Aviation engine lamina belongs to function and structure to compare complex product, want the job to be below the condition of high temperature, high pressure and high load capacity already, want to have the characteristic of efficient, minor volume and low weight again. Accordingly, problem of design of aviation engine lamina is paid close attention to by the key inside the industry [1-4] . Company of 1 GE of 　 of brief introduction of technology of CAD of foreign aviation engine at 20 centuries 60 time later period began CAD technology to apply mediumly in aviation engine research and development, built the CIMS of aircraft engine branch 1980, make productivity rises, cost is reduced. 1985, in engine the design optimizes technical base to go up, began to develop to be used at the design to optimize, automation is compositive optimized software platform Engineous, CUS of software of design of the turbine design software Engineous and own research and development and TDOD of system of analysis of blame design condition, compressor compositive, very ideal result was obtained in the design of compressor and turbine. Later, engineous has developed become the software platform ISIGHT that is used at large and complex product to optimize a design. 20 centuries of 　 of company of R of 2 R · 60 time metaphase, begin to use CAD technology in the design of blade, completed pneumatic analysis, stress analysis, oscillatory analysis and modelling design, store geometrical model use at treatment to examine in the database. 80 time metaphase, built the design computation system of crucial part, expanded CAD technology detailed design branch is mixed production branch, it is CAD with CADDS the three-dimensional software that build a model, developed RADIAL database to regard the central geometry of CAD/CAM and technical system as graph file system. 80 time evening, the collateral project of executive engine, be based on product definition, design process definition and product information support, built the computer work environment that cooperate with, specific undertook impeller of 3-D centrifugal compressor is optimized. 3 PW company was worn early namely 1965 the design that the hand studies to use CAD/CAM technology at aviation to light gas turbine engine / in making. Development turbine blade profile designed systematic TADSYS 1968, make the project analysed time to shorten 5/6, rose to design quality, enhanced judgement ability of the engineer. The seesaw pattern turbine that further 1974 progress designs inside to include pneumatic designs a system. Develop a compressor to design systematic CAMD in succession, STAEBC of engine construction processing system, started again later spend the Q+ that is core with user satisfaction (Qulity Plus) project, begin to use a group (Team) the form will run engine all economic technology activities inside complete lifecycle, had developed at present become the compositive product that is core with collateral project to develop (Integrated Product Development, IPD) , use collateral project idea namely, become a basis with information market, produce the design, each link that the product such as user support develops are compositive in a group, will decrease through the continual communication between different major repeat a design, improve design quality. Development of technology of CAD of aviation engine lamina and the aviation engine that the problem analyses our country develop ability earnestly to need to rise. Current, engine of our country aviation is developing a level to go up to still have apparent difference with foreign developed country. The company of western country can develop motive setting out 3 years, namely from decide project approving of a model arrives engine is overall come out, and home does two model engine is when using 18 years, spent western country the time of 6 times, gap is huge [5] . The United States studies in the CAD technology of turbine engine the respect goes in world front row. The IHPTET of 1 United States plans [the United States made 6] 　　 1988 and carried out IHPTET (The Integrated High Performance Turbine Engine Technology, technology of engine of integrated high-powered turbine) plan, among them a very main task is begun namely advance systematic numerical value to emulate a plan (Numerical Propulsion System Simulation, NPSS) , the main goal of this plan is through the much discipline with reliable height integrated computer emulates the systems analysis capacity that reachs height, design quality in order to raise engine, reduce development cost. This plan is emulated in the one dimension that achieved engine 1997, the 2 dimension that achieved engine 1999 are emulated, the plan realized three-dimensional and dynamic much discipline to emulate 2010, plane of final implementation / engine is emulated integratedly. According to saying, once this one plan comes true, the design level of American aviation engine will realize a new leap, predict to be able to make the development cost of engine is reduced again 40% . The APTD of 2 our country plans [on the foundation of the successful experience that 7] 　 is absorbing American IHPTET to plan, our country rolled out APTD (Advanced Propulsion Technologies Demonstration, aviation advances technical test and verify) plan. APTD is a when the country drives to develop advanced aviation engine integrated systematization project, it is one is not aimed at the engine technology of specific type to push a plan. The hope can form a whole system that serves as platform with contemporary informatization method through APTD plan standard, design development in whole aviation engine next apply ceaselessly in the process. In APTD plan, regard aviation engine the subsystem of whole plane, be about to its consider integratedly as the component of the plane, have engine the research that advanced aviation advances a technology. 3 boat send issue of blade CAD technology to analyse the design of lamina of engine of our country aviation, in product structure the respect that build a model was experienced from 2 dimension handiwork n/arc drafting arrives drawing of 2 dimension computer, propose modular change to three-dimensional substance again; Be analysed in function and the change of the digital prototype that analyses union of phase of as auxiliary as the computer project from physical prototype test and verify was experienced on test and verify. The design of aviation engine lamina, it is one of crucial parts of the fictitious prototype of aviation engine, the function of efforts of the much link that is a model, much discipline, much department and structure compare complex product. It is with turbine lamina exemple, if the graph is shown 1 times,the plan of its structure designs circuit. Nextpage 　 lamina is the most complex part in engine, its design quality and cost to affect the quality of engine and price directly. Development of engine of aviation of foreign high level is based on at 2 o'clock: It is the design ability that the newest maths model with updating development ceaselessly promotes it as software; 2 be serve as with giant database prop up make the model can apply effectively [5] . Needed tool of research and development and the support that devise a method this at 2 o'clock, more such to the design of aviation engine lamina. Method of traditional product geometry design and pure the handiwork that depends on general CAD platform devises way, the fast geometry that cannot have satisfied blade structure designs a requirement, more come true to be revised quickly hard [8] . The design software such as large CADCAE is used in designing a process, because the coupling sex between design link is not strong, make every design link becomes independent automation to design information Gu island. Swim in fluctuation between design link, design data utilization rate is low, need design personnel is done many, iteration data duplicates extraction job. Design personnel gets the limitation of domain knowledge, make active support to going up to design link downstream hard, add those who added design difficulty and design to repeat greatly degree, the design quality that affects turbine lamina directly rises with what design efficiency. The design issue that be in is put in lamina of engine of aviation of current our country is being analysed specificly to design a process below. (1) respect of ongoing hair tool, need research and development develops a tool to prop up the structural design of blade. The relationship is close between firm of design of foreign aviation engine and design software company, have core to design the complete property right of software even. For instance the Engineous software itself of GE company is one of products of the company, final development optimizes design software for commercial much discipline. And capacity of development of software of large and own design is finite, build in the product model, function is analysed and optimize the respect such as the design, combine own development department to divide the applied mode of subdesign software to basically introduce core CAD/CAE to design software commonly. The application that digitlizes design technology and software rose to design efficiency, but a lot of problems still exist in designing a process, if the product builds modification problem of model and parameter, product,analytic process builds modular problem and automation to design a problem to wait. Traditional product geometry designs method and the handiwork that are based on general CAD platform to devise way, the fast geometry that cannot have satisfied turbine lamina structure is designed, more come true to be revised quickly hard. (2) in knowledge engineering (Knowledge Based Engineering, KBE) respect, it is relatively difficult that the product that is based on much territory knowledge builds a model, need introduces the subdesign method software such as CAECAO to undertake optimizing designing. The design function demand of lamina of aviation engine turbine is higher, working requirement is slashing, the structure is very complex, the appearance of every stature structure and parameter are right more than a performance data produces an effect, if lie between the change of costal region position, affect the distributinging position of the greatest stress and size not only, still affected cooling effect and pneumatic efficiency; The number of gas film opening increases, although enhanced cooling gas and high temperature to light angry mix into to mix action, improved cooling result, but reduced blade intensity however; Increase faze to shed costal region and faze to shed column, the flow time that increased air conditioning not only and with blade inside model contact an area, enhanced cooling result, also added the weight of blade. Additional, the adjustment of blade structure and parameter still affects blade natural frequency directly. Be aimed at afore-mentioned problems, although domestic and international investigator did many objective to experiment to be summed up from which with emulation experiment gave a lot of computation formula, but these knowledge are accumulated can use at plan design phase only, build the approximate and initiative model of blade structure namely. The graph shows the CAD that is some engine lamina 2 times to emulate a model. In phase of blade detailed design, still need to be based on CAE software to undertake function is analysed, the figure that adjusts foliaceous film structure as a result according to computation and geometrical parameter ask with satisfying a design. (3) designing flow respect, the CAD/CAE of aviation engine lamina designs the coupling sex difference between link, the automation rate that designs circuit is inferior, need considers to design a method to support the automation of products plan flow. The main trend was used in CAD/CAE design process general design software, because design personnel to get the limitation of the complexity of much discipline of domain knowledge and turbine lamina, make every information Gu island that designs link to become independence, make active support to going up to design link downstream hard, design data utilization rate is low. Need design personnel is done many, iteration model reframes, parameter is adjusted and data duplicates extraction job, the tradition that still keeps in digitlization to design circuit uses level. (4) in optimize design respect, need introduces the computer to assist optimize a method. The design quality of turbine lamina, namely the level that unit parameter place reachs, basically depend on uses design method and choose parameter approach the level at best parameter. Design link accordingly in turbine lamina in, using digitlization to design a technology have advantage and economic actual effect for its itself, but cannot the time that development of greatly cut engine spends and financial capacity, material resources, more cannot from go up at all the design quality that improves a product. The function design of turbine lamina needs to design plan to have trade off study in great quantities, when product function malcontent sufficient design asks when, because design software between non-automati change, design personnel is main by already design experience and criterion adjust design parameter artificially; Structural design is designed the job complex, trival, the tall difficulty of the design, Gao Fu is miscellaneous degree of limitation with high strenth, satisfy the requirement that function designs hard, to the design of turbine lamina efficiency and design quality produced immediate effect. So, should use the computer to assist optimize a method, plan option comes true in the computer, calculate according to mathematical model the entire character of plan of every products plan. Be based on what these character comprise to optimize criterion, will undertake the comprehensive assessment of the product singles out optimal program. Technology of CAD of lamina of engine of our country aviation considers to make progress to solve the design problem of afore-mentioned aviation engine lamina, raise turbine lamina to design automation rate of the job, must be summed up deep and analyse the CAD technology that is aimed at aviation engine lamina. Scholar of a few experts devotes oneself to the research of technology of CAD of lamina of aviation engine turbine and application actively, solved aviation engine lamina to design medium partial issue. The unit of research basically is centered in machinery of motivation of aviation of Tsinghua university, Harbin Institute of Technology, individual plant continent 6 units such as university of aerospace of university of industry of institute, northwest, Nanjing and Beijing aerospace university. Study content basically centers in 3 respects: (1) the geometry of blade profile and foliaceous body expresses; (2) blade structure design; (3) blade optimizes a design integratedly. The geometry in designing a process in the light of blade is emphasized to build modular problem and technology to undertake be elaboratinged deep below. 1 blade profile of Nextpage 　　 and foliaceous body geometry represent blade profile, namely foliaceous body is sectional line. Blade profile and the geometry of foliaceous body curved surface express the premise that is blade structure design. Blade profile and foliaceous body curved surface are a kind complex, relatively complex freedom curve, curved surface, cannot be described with groovy and elementary curve, curved surface, the heat that their modelling method is people research all the time [9] . Foliaceous body curved surface is folded as base line accumulating by many blade profile and become, cent is folded for linear accumulating and nonlinear indigestion fold [10] , its shape the method is envelope [11] . Essence of modelling of turbine lamina geometry finds a kind to satisfy appearance effectively to express to design a requirement with geometry already namely, the mathematical method that facilitates appearance information and the form that product data exchanges are described again will describe turbine lamina curved surface [12] . The place that difficulty of formative of foliaceous body curved surface depends on the curvature such as leading edge and end predestined relationship changing quickly is easy produce twist. Expressed the Wang Gang of Harbin Institute of Technology to have thorough research to geometry of foliaceous body curved surface [9, 13-14] , he studied the curved surface modelling of screwy lamina, whole of pair of curved surface of 3 B batten are used to express foliaceous body curved surface below cylinder coordinate department, was based on BP nerve network to improve the interpolation error that leading edge and end predestined relationship are in foliaceous body curved surface. NURBS method expresses agile, have local sex, express accurately what united elementary curve, curved surface and freedom curve, curved surface, in view of NURBS method this a series of advantages, the Li Gang of Harbin Institute of Technology and Wang Gang, studied what foliaceous body curved surface is based on NURBS to represent a means respectively [14-15] . The Wang Chunxia of Beijing aerospace university [16] , the disperse in discussing foliaceous body to establish modular procedure nods the crucial question such as processing, the model of dimensional batten curved surface that introduces pair of 3 B batten to planned to combine blade aspect. The Tian Qing of northwest industry university [17] was based on UG to develop system of foliaceous body model, studied the issue of joining together of blade profile curve of sectional line mainly. White [18] and Liu Weiwei [19] in the light of blade modelling easy happening the research of method of correction that screwy phenomenon had reseau twist, labor the problem in modelling of foliaceous body curved surface and reason, use ply feature to nod parameter to adjust method and parameter of blade profile whole to change a method, be based on wait for parameter or wait for arc length lofting to shape foliaceous body curved surface, solved problem of twist of formative of foliaceous body curved surface. Design of 2 lamina structure designs a respect in blade structure, it is the fast design that the library of with be aimed at blade structure feature special design feature that defines beforehand has a structure for the foundation commonly, the crucial technology that it involves has diagnostic analysis, feature to build model and diagnostic parameter to change etc. The anxiety of northwest industry university crosses the sea [20] is based on analytic and the parameter that diagnostic modelling has blade changes a design, realized foliaceous body, predestined relationship board, rabbet and circumfluence passageway (lie between costal region) the parameter that waits for a feature changes a design, the tectonic process parameter that belongs to seesaw pattern is changed. The Zhao Wei of Beijing aerospace university [the 21] structure that is based on STEP to have blade on honeysuckle platform designs research, undertook to the structure of blade the feature is analysed designing, gave out framework of system of blade structure design. Wang Rongqiao [the structure that 22-23] developed compressor lamina designs a system, from the definition with the user the feature is a foundation, the respect was optimized to do initial exploration in blade structure. Document [24] uses pair of 3 B batten to have foliaceous body curved surface express, the structure that is aimed at turbine has turbine blade classification of characteristics, properties shows the labor with diagnostic parameter, the parameter that uses the parameter that is based on a feature to change design method to realize turbine lamina changes a design, finished parameter to change the initial design that designs a system, specific realized foliaceous body inside and outside substance, predestined relationship board, rabbet the waits for mural thick lamina structure parameter of amiable film opening changes a design, the parameter leaving a line that belongs to seesaw pattern changes a design. Document [8] undertakes to the system further detailed and perfect, came true to lie between costal region, faze to shed column and exhaust end to seam the parameter that waits for a feature to change a design again. Changing the structural parameter of mural thick lamina changes design aspect, document [25] put forward the arc in be based on change mural thick design is algorithmic, the ply parameter that with 6 walls of every blade profile large sign dot is in controls blade wall thick, 4 kinds of walls that this algorithm can design project middling to see are large distributinging lamina. Curve plan is implementation to change in the premise that structure of mural thick lamina designs. Be in in curve computation respect, the white of northwest industry university [18] puts forward to be based on inside cut equidistant the arc in iteration is algorithmic, but 2 when carry a curve on the back to be in in inscribed circle point of tangency when foliaceous basin curve and leaf are cut included angle spends a hour between arrow, the method may not have solution, and computational amount is large. Tensional peace undertook improvement to this, those who put forward to be based on equidistant line is medium curve is algorithmic [26] . But, the arc in equidistant line means passes narrow point interpolation and shaping, model be worth those who nod density to be able to charge a sex poorer. Accordingly, document [25] put forward to be based on conduit to cross a line of umbriferous law in curve is algorithmic, the computational efficiency of the arc in rising significantly, be based on conduit to handed in a line to the arc in umbriferous law calculative puts forward and come true to change the structural design of lamina of mural thick turbine. Respect of put sb in a very important position is designed in blade structure, the Xia Yu of northwest industry university [of the model of information of broad sense feature that 27] offers to be based on knowledge and the tree of CSG of broad sense feature that record design history represent a means, in the list of news of broad sense feature at XML format, realized design process save. The Zhao Hui of Beijing aerospace university [28] , combine the structural characteristic of lamina of aviation engine turbine, on the foundation that in the feature attribute of extraction, feature and operation analyse, put forward to be based on feature and method of put sb in a very important position of object-oriented denotive model. 3 lamina optimize design lamina integratedly to optimize the necessary premise of the design integratedly, it is blade profile parameter is changed and parameter of foliaceous body curved surface is changed. Blade profile parameter changes design method to have section notation and integral notation commonly 2 kinds. Express from geometry, sectional parameter changes blade profile design method can differentiate for analytic law (be 3 times commonly or 5 multinomial, or Hicks-Henne function) , batten of Bezier, B and NURBS 4 are planted method. Can divide from implementation means change for program parameter, parameter of online and seesaw pattern is changed and change 3 kinds from line type parameter. Parameter of blade profile program is changed is the crucial link that blade optimizes a design integratedly. The Zhou Zhenggui of Nanjing aerospace university [5-7, 29] uses polynomial parameter to change compressor lamina blade profile, combinative simplex numerical value optimizes algorithm of method, mixture heredity, change a method to represent blade profile with Hicks-Henne function parameter, combine collateral and genetic algorithm, those who had compressor blade is automatic optimize a design. The anxiety of northwest industry university crosses the sea to wait [20, 30] uses polynomial parameter 5 times to change the method of blade profile curve, had turbine blade three-dimensional optimize a design to consider. King Jing of superior grade [31] was aimed at problem of coupling of turbine lamina much field to have thorough research, with unit linear interpolation finishs pneumatic, conduct heat and of information of the load between structural course deliver, the parameter that uses polynomial method 5 times to have three-dimensional turbine blade is changed build a model, heredity of associated much island and law of program of 2 order line undertake finding actor to the problem. Shang Ren is held etc [32] used parameter model law and Bezier curve to have blade preliminary modelling, use algorithm of much target heredity and series 2 times algorithmic combination optimizes algorithm, through adjusting the parameter of crucial reference point of attraction face and pressure area is opposite its pressure loss and turn horn undertake optimizing. Die of Beijing aerospace university Home Deng [10, 33] in turbine lamina much discipline of plan of one dimension pneumatic optimizes design foundation to go up, be based on Bezier to combine circular arc section to state parameter changes blade profile again, the much discipline that had turbine blade optimizes a design. Zhu Jian [34] and Ma Hongbo [35] use the 12 parameter law that is based on B batten curve to undertake blade profile parameter changes a design, the three-dimensional pneumatic that is based on this parameter to changed design method to realize boat to send turbine lamina further optimizes a design. This method designs parameter to design parameter to control blade profile for geometry with blade profile, the parameter that changes union to change the mixture means of the design to realize blade from line parameter with program parameter changes a design, raised a design to be spent freely, more accord with design habit. The Chen Bo of Tsinghua university [11, the Liu Bo of 36-37] and northwest industry university [the parameter that 38] is based on NURBS to have blade profile sectional line changes a design, was based on artificial nerve network to undertake the pneumatic of blade optimizes design research respectively. Wu Lijiang of institute of machinery of motivation of aviation of individual plant continent [39] , optimized a design to undertake study to the much discipline of turbine lamina, defined 26 designs variable to describe turbine lamina blade profile; Cai Xianxin [40-41] undertook to integral centrifugal impeller appearance optimizes a design to consider. Engine of last word aviation is " the imperial crown of modern manufacturing industry " , and blade is its key spare parts, scholar of domestic and international expert made much research work to the design of blade. Want to raise blade to basically design the working automation rate of link each, must consider to design method, technology deep, improve design method, the problem that CAD of lamina of engine of our country aviation faces to study the technology exists below undertakes an analysis. (1) blade profile and the geometry of foliaceous body curved surface express and parameter is changed gained certain headway, mainstream method is what be a foundation with B batten and NURBS curve, curved surface is multistage curvilinear blade profile represents a means, light of curved surface of body of the blade profile that brings according to delivering by number, leaf arranges pair of pneumatic to design precision to affect will be the problem that remains to consider. (2) blade structure design had laid better foundation, but relatively ambiguous to the tie and those who ask to compare feature of strict free curved surface again build a model to still consider to be not worth, the freedom that bends back lamina and lamina for instance extend a root to wait. The fast and accurate geometry of these complex features builds a model to still need to have thorough research. (3) blade optimizes design respect integratedly, what come true at present is the much discipline that gives priority to with pneumatic design optimizes a design, more complex structure optimizes research integratedly less still, the reason is partial key technology, what if geometrical model is compact, fast,stabilize is finite yuan reseau differentiates algorithmic, attrib border condition is defined and the information between coupling of to load, much discipline, much discipline is delivered and complex system much discipline optimizes efficiency to wait for crucial question to still remain to study deep. How be based on already some large CADCAECAO software develop partial key software and program to build compositive design system independently, how what apace builds blade is complex and automatic optimize design technological process, how be based on already design example summary gives corresponding design knowledge and method to undertake designing put sb in a very important position, will be the stress research way that settles aviation engine lamina to design an issue. CNC Milling