大規(guī)模結(jié)構(gòu)高效靜氣彈多學(xué)科優(yōu)化設(shè)計(jì)研究
發(fā)布時(shí)間：2018-12-15 07:04
【摘要】：現(xiàn)代飛機(jī)結(jié)構(gòu)的輕量化需求使得機(jī)翼柔度變大,靜氣彈效應(yīng)愈加顯著。傳統(tǒng)工程結(jié)構(gòu)設(shè)計(jì)優(yōu)化往往只考慮結(jié)構(gòu)本身的強(qiáng)度剛度性能,并未直接考慮靜氣彈效應(yīng)帶來的諸如飛機(jī)升力效率、副翼效率、焦點(diǎn)位置變化等影響,這使得無法獲得滿足不同學(xué)科需求的最佳結(jié)構(gòu)。隨著現(xiàn)代飛機(jī)結(jié)構(gòu)更精細(xì)化設(shè)計(jì)以及更深層次挖掘結(jié)構(gòu)潛能的需求,結(jié)構(gòu)設(shè)計(jì)變量的數(shù)量和各學(xué)科模型的規(guī)模越來越大,結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化方法在處理這種大規(guī)模優(yōu)化問題時(shí)面臨著求解效率低、計(jì)算代價(jià)大以及導(dǎo)數(shù)信息獲取困難等挑戰(zhàn),這限制了飛機(jī)結(jié)構(gòu)的進(jìn)一步精細(xì)優(yōu)化設(shè)計(jì)。本文旨在通過改進(jìn)亞聲速工程面元法求解精度,提高靜氣彈求解效率以及構(gòu)造靜氣彈設(shè)計(jì)敏度算法等,與大規(guī)模結(jié)構(gòu)優(yōu)化方法結(jié)合,力圖解決大規(guī)模結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化面臨的技術(shù)難點(diǎn),主要研究工作如下:為著實(shí)現(xiàn)機(jī)翼彈性氣動(dòng)載荷的高效率與高精度計(jì)算,針對(duì)高精度計(jì)算流體力學(xué)(CFD)方法計(jì)算耗時(shí)過長(zhǎng)的矛盾,本文采用工程處理觀點(diǎn),提出了一種改進(jìn)的亞聲速工程面元法—分段精細(xì)修正面元法。技術(shù)途徑為:采用多個(gè)迎角下的剛性機(jī)翼高精度CFD氣動(dòng)力數(shù)據(jù),進(jìn)行工程面元法的分段修正,獲取多段修正因子矩陣;同時(shí),將機(jī)翼彈性變形的下洗分段,利用所獲取的修正因子矩陣提高機(jī)翼彈性氣動(dòng)載荷的計(jì)算精度與效率。為進(jìn)一步提高分段精細(xì)修正面元法計(jì)算精度,本文提出了一種面元網(wǎng)格劃分優(yōu)化算法,該算法以機(jī)翼面元展向和弦向劃分?jǐn)?shù)目為優(yōu)化變量,以靜氣彈計(jì)算中機(jī)翼在一較大彈性變形下的高精度CFD氣動(dòng)力數(shù)據(jù)為基礎(chǔ),在ISGHIT軟件平臺(tái)上對(duì)面元網(wǎng)格實(shí)現(xiàn)最優(yōu)劃分,使得最優(yōu)面元網(wǎng)格劃分下的修正面元法彈性氣動(dòng)載荷計(jì)算結(jié)果與高精度CFD結(jié)果更為接近。為提高氣動(dòng)與結(jié)構(gòu)耦合界面的數(shù)據(jù)傳遞精度與效率,本文采用數(shù)值精度高、適應(yīng)性好的基于徑向基函數(shù)(RBF)數(shù)據(jù)傳遞方法,并對(duì)其緊支半徑以及傳遞節(jié)點(diǎn)及其數(shù)量提出了選擇規(guī)則,提高了RBF方法的計(jì)算效率。工程中的靜氣彈性能往往采用簡(jiǎn)單定義,不能完全反映靜氣彈效應(yīng)給飛機(jī)氣動(dòng)效率及操穩(wěn)特性帶來的影響。本文采用靜氣彈性能的精確定義并利用復(fù)步長(zhǎng)求導(dǎo)方法,結(jié)合分段精細(xì)修正面元法構(gòu)造了求解升力效率、副翼效率、焦點(diǎn)弦向位置變化率的高效算法,完成了算法程序設(shè)計(jì)。其中,提出一種雙重迭代計(jì)算副翼效率的方法,不但能準(zhǔn)確求解副翼效率還能計(jì)算飛機(jī)定常滾轉(zhuǎn)速率,充分反映了機(jī)翼彈性和副翼偏角給飛機(jī)滾轉(zhuǎn)機(jī)動(dòng)性能帶來的影響。為了給予設(shè)計(jì)者更多的參考信息,本文還提出了彈性升力迎角補(bǔ)償算法以及彈性滾轉(zhuǎn)速率副翼偏角補(bǔ)償算法,以求得定載與定速滾轉(zhuǎn)情況下的迎角補(bǔ)償量與副翼偏角補(bǔ)償量;同時(shí),設(shè)計(jì)了機(jī)翼發(fā)散速度與反效速度的低階估算算法�；谔荻刃畔㈩惖膬�(yōu)化算法是大規(guī)模結(jié)構(gòu)數(shù)值優(yōu)化常用的一種高效算法,為了給予這類優(yōu)化方法導(dǎo)數(shù)信息支持,本文利用所提出的分段精細(xì)修正面元法構(gòu)造了靜氣彈設(shè)計(jì)敏度半解析算法,并采取多項(xiàng)措施提高其計(jì)算效率。為適應(yīng)大規(guī)模結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化程序的模塊化組織,本文編寫了求解高效、讀寫規(guī)范的靜氣彈求解程序模塊,并通過OPENMP并行技術(shù)進(jìn)一步提高了程序計(jì)算效率。通過M6機(jī)翼靜氣彈性能算例考察,并與高精度CFD數(shù)據(jù)、NASTRAN軟件計(jì)算結(jié)果比較,表明本文提出的多項(xiàng)靜氣彈性能求解算法以及程序設(shè)計(jì)具有精度高、效率好的技術(shù)優(yōu)勢(shì)。最后,綜合分析了結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化的原理與特點(diǎn),并利用.MASS文件實(shí)現(xiàn)不同工況下不同集中質(zhì)量加載。文中總結(jié)了工程中常用的結(jié)構(gòu)設(shè)計(jì)約束,闡述了本課題組開發(fā)的大規(guī)模結(jié)構(gòu)優(yōu)化程序中的數(shù)值優(yōu)化算法以及約束篩選、變量降維、文件組織、并行處理等核心技術(shù)。在該程序基礎(chǔ)上,本文完成了靜氣彈性能約束的并入集成,形成了大規(guī)模結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化程序。在此工作基礎(chǔ)上,本文對(duì)一飛翼無人機(jī)結(jié)構(gòu)采用699個(gè)設(shè)計(jì)變量,施加4種強(qiáng)度設(shè)計(jì)工況、2種飛行工況以及近10種約束,進(jìn)行了結(jié)構(gòu)靜氣彈多學(xué)科數(shù)值優(yōu)化計(jì)算,并對(duì)優(yōu)化結(jié)果進(jìn)行了分析校驗(yàn)。結(jié)果表明本文采用的大規(guī)模結(jié)構(gòu)靜氣彈多學(xué)科優(yōu)化方法計(jì)算高效,并減少結(jié)構(gòu)重量15.66%,優(yōu)化結(jié)果滿足工程約束。另外,通過5種不同的約束組合進(jìn)行結(jié)構(gòu)多學(xué)科優(yōu)化結(jié)果比較,分析了各約束對(duì)結(jié)構(gòu)重量的影響,以助于發(fā)掘結(jié)構(gòu)設(shè)計(jì)規(guī)律。
[Abstract]:The light-weight demand of modern aircraft structure makes the wing soft degree become large, and the static-gas bomb effect is more significant. The optimization of the traditional structural design often only takes into account the strength and rigidity performance of the structure itself, and does not directly take into account the influence of the static-gas effect, such as the lift efficiency of the airplane, the aileron efficiency, the change of the focus position, and the like, which makes it impossible to obtain the best structure to meet the needs of different disciplines. With the more refined design of the modern aircraft structure and the need of the deeper excavation of the structural potential, the number of structural design variables and the scale of each subject model are becoming larger and larger, and the multi-disciplinary optimization method of the structure static gas bomb is faced with low solution efficiency in the process of processing the large-scale optimization problem, The computational cost and the difficulty of obtaining the derivative information have limited the further fine-tuning design of the aircraft structure. The purpose of this paper is to solve the technical difficulties faced by the multi-disciplinary optimization of large-scale structure static-gas bomb by improving the accuracy of the sub-sonic engineering surface element method, improving the solution efficiency of the static-gas bomb and the design of a static-gas bomb, and combining with the large-scale structure optimization method. The main research work is as follows: In order to realize the high efficiency and high precision calculation of the elastic pneumatic load of the wing, the problem that the time consuming is too long is calculated for the high-precision computational fluid dynamics (CFD) method. In this paper, an improved sub-segment fine correction surface element method for subsonic engineering is presented. The technical method comprises the following steps of: adopting high-precision CFD aerodynamic data of a rigid wing at a plurality of angles of attack, performing section correction of the engineering surface element method, acquiring a multi-section correction factor matrix, and simultaneously, and the calculation accuracy and the efficiency of the wing elastic pneumatic load are improved by utilizing the acquired correction factor matrix. in ord to further improve that calculation accuracy of the segment fine correction surface element method, a surface element mesh partition optimization algorithm is proposed, On the basis of the high-precision CFD aerodynamic data of the wing under a large elastic deformation, the optimal division of the meta-grid is realized on the ISGHIT software platform, so that the calculation of the elastic aerodynamic load of the modified plane element method under the optimal plane element mesh is more close to the high-precision CFD result. In order to improve the data transfer precision and efficiency of the coupling interface between the pneumatic and the structure, this paper adopts the radial basis function (RBF) data transmission method with high numerical precision and good adaptability, and puts forward the selection rules for the compact radius and the number of the transmission nodes and the transmission nodes. and the calculation efficiency of the RBF method is improved. The static and static elastic energy in the project often adopts a simple definition, and can not completely reflect the influence of the static-gas elastic effect on the aerodynamic efficiency and the operation stability of the aircraft. In this paper, the precise definition of the static and elastic energy is used and the complex step method is used, and a high-efficiency algorithm for solving the change of the lift efficiency, the aileron efficiency and the position change rate of the focal chord is constructed in combination with the segmented fine correction surface element method, and the algorithm programming is completed. In this paper, a double-iteration method for calculating the aileron efficiency is proposed, which not only can accurately solve the aileron efficiency but also can calculate the steady roll rate of the airplane, and fully reflects the influence of the wing elasticity and the aileron deflection angle to the rolling mobility of the airplane. In order to give the designer more reference information, an elastic lift angle-of-attack compensation algorithm and an elastic roll-rate aileron-off-angle compensation algorithm are presented in this paper to determine the angle-of-attack compensation and the amount of the aileron-off-angle compensation in the case of fixed-load and constant-speed rolling, and at the same time, A low-order estimation algorithm for the speed of divergence and the velocity of the wing is designed. The optimization algorithm based on the gradient information class is a kind of high-efficiency algorithm used in large-scale structure numerical optimization. In order to support the derivative information of this kind of optimization method, this paper constructs a half-resolution algorithm for the design of static-gas bomb by using the proposed segmentation fine correction surface element method. and a plurality of measures are taken to improve the calculation efficiency. In order to adapt to the modular organization of the multi-subject optimization program of large-scale static-gas bomb, this paper has developed a static-gas bomb solution program module for high-efficiency and read-write specifications, and further improves the program calculation efficiency through OPENNMP parallel technology. Through the study of the static and elastic energy of the M6 wing, and compared with the high-precision CFD data and the NASTRAN software, it is shown that the multiple static-gas elastic energy-solving algorithm and the programming have the advantages of high precision and high efficiency. In the end, the principle and characteristics of the multi-disciplinary optimization of the structure static-gas bomb are comprehensively analyzed and used. The mass loading of different concentration under different working conditions is realized by the MASS file. In this paper, the structure design constraints commonly used in the project are summarized, the numerical optimization algorithm in the large-scale structure optimization program developed by the research group, and the core technologies such as constraint selection, variable drop-down, file organization and parallel processing are described. On the basis of this program, this paper completes the integration of the static and gas elastic energy constraints, and forms a large-scale structure static-gas multi-disciplinary optimization program. On the basis of this work, 699 design variables are used in the structure of a flying-wing unmanned aerial vehicle, four strength design conditions, two flight conditions and nearly 10 constraints are applied, and the multi-subject numerical optimization calculation of the structure static-gas bomb is carried out, and the optimization result is analyzed and verified. The results show that the large-scale structure static-gas multi-disciplinary optimization method is efficient and reduces the structural weight by 15.66%, and the optimization results meet the engineering constraints. In addition, the influence of each constraint on the weight of the structure is analyzed through the comparison of five different constraint combinations to the structural multi-subject optimization results, so as to help to find out the law of the structural design.
【學(xué)位授予單位】：西北工業(yè)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：V279
，
本文編號(hào)：2380195
[Abstract]:The light-weight demand of modern aircraft structure makes the wing soft degree become large, and the static-gas bomb effect is more significant. The optimization of the traditional structural design often only takes into account the strength and rigidity performance of the structure itself, and does not directly take into account the influence of the static-gas effect, such as the lift efficiency of the airplane, the aileron efficiency, the change of the focus position, and the like, which makes it impossible to obtain the best structure to meet the needs of different disciplines. With the more refined design of the modern aircraft structure and the need of the deeper excavation of the structural potential, the number of structural design variables and the scale of each subject model are becoming larger and larger, and the multi-disciplinary optimization method of the structure static gas bomb is faced with low solution efficiency in the process of processing the large-scale optimization problem, The computational cost and the difficulty of obtaining the derivative information have limited the further fine-tuning design of the aircraft structure. The purpose of this paper is to solve the technical difficulties faced by the multi-disciplinary optimization of large-scale structure static-gas bomb by improving the accuracy of the sub-sonic engineering surface element method, improving the solution efficiency of the static-gas bomb and the design of a static-gas bomb, and combining with the large-scale structure optimization method. The main research work is as follows: In order to realize the high efficiency and high precision calculation of the elastic pneumatic load of the wing, the problem that the time consuming is too long is calculated for the high-precision computational fluid dynamics (CFD) method. In this paper, an improved sub-segment fine correction surface element method for subsonic engineering is presented. The technical method comprises the following steps of: adopting high-precision CFD aerodynamic data of a rigid wing at a plurality of angles of attack, performing section correction of the engineering surface element method, acquiring a multi-section correction factor matrix, and simultaneously, and the calculation accuracy and the efficiency of the wing elastic pneumatic load are improved by utilizing the acquired correction factor matrix. in ord to further improve that calculation accuracy of the segment fine correction surface element method, a surface element mesh partition optimization algorithm is proposed, On the basis of the high-precision CFD aerodynamic data of the wing under a large elastic deformation, the optimal division of the meta-grid is realized on the ISGHIT software platform, so that the calculation of the elastic aerodynamic load of the modified plane element method under the optimal plane element mesh is more close to the high-precision CFD result. In order to improve the data transfer precision and efficiency of the coupling interface between the pneumatic and the structure, this paper adopts the radial basis function (RBF) data transmission method with high numerical precision and good adaptability, and puts forward the selection rules for the compact radius and the number of the transmission nodes and the transmission nodes. and the calculation efficiency of the RBF method is improved. The static and static elastic energy in the project often adopts a simple definition, and can not completely reflect the influence of the static-gas elastic effect on the aerodynamic efficiency and the operation stability of the aircraft. In this paper, the precise definition of the static and elastic energy is used and the complex step method is used, and a high-efficiency algorithm for solving the change of the lift efficiency, the aileron efficiency and the position change rate of the focal chord is constructed in combination with the segmented fine correction surface element method, and the algorithm programming is completed. In this paper, a double-iteration method for calculating the aileron efficiency is proposed, which not only can accurately solve the aileron efficiency but also can calculate the steady roll rate of the airplane, and fully reflects the influence of the wing elasticity and the aileron deflection angle to the rolling mobility of the airplane. In order to give the designer more reference information, an elastic lift angle-of-attack compensation algorithm and an elastic roll-rate aileron-off-angle compensation algorithm are presented in this paper to determine the angle-of-attack compensation and the amount of the aileron-off-angle compensation in the case of fixed-load and constant-speed rolling, and at the same time, A low-order estimation algorithm for the speed of divergence and the velocity of the wing is designed. The optimization algorithm based on the gradient information class is a kind of high-efficiency algorithm used in large-scale structure numerical optimization. In order to support the derivative information of this kind of optimization method, this paper constructs a half-resolution algorithm for the design of static-gas bomb by using the proposed segmentation fine correction surface element method. and a plurality of measures are taken to improve the calculation efficiency. In order to adapt to the modular organization of the multi-subject optimization program of large-scale static-gas bomb, this paper has developed a static-gas bomb solution program module for high-efficiency and read-write specifications, and further improves the program calculation efficiency through OPENNMP parallel technology. Through the study of the static and elastic energy of the M6 wing, and compared with the high-precision CFD data and the NASTRAN software, it is shown that the multiple static-gas elastic energy-solving algorithm and the programming have the advantages of high precision and high efficiency. In the end, the principle and characteristics of the multi-disciplinary optimization of the structure static-gas bomb are comprehensively analyzed and used. The mass loading of different concentration under different working conditions is realized by the MASS file. In this paper, the structure design constraints commonly used in the project are summarized, the numerical optimization algorithm in the large-scale structure optimization program developed by the research group, and the core technologies such as constraint selection, variable drop-down, file organization and parallel processing are described. On the basis of this program, this paper completes the integration of the static and gas elastic energy constraints, and forms a large-scale structure static-gas multi-disciplinary optimization program. On the basis of this work, 699 design variables are used in the structure of a flying-wing unmanned aerial vehicle, four strength design conditions, two flight conditions and nearly 10 constraints are applied, and the multi-subject numerical optimization calculation of the structure static-gas bomb is carried out, and the optimization result is analyzed and verified. The results show that the large-scale structure static-gas multi-disciplinary optimization method is efficient and reduces the structural weight by 15.66%, and the optimization results meet the engineering constraints. In addition, the influence of each constraint on the weight of the structure is analyzed through the comparison of five different constraint combinations to the structural multi-subject optimization results, so as to help to find out the law of the structural design.
【學(xué)位授予單位】：西北工業(yè)大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：V279
，
本文編號(hào)：2380195
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