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Thus, the parallel multiblock full NavierStokes code can be successfully used for largescale practical aerodynamic simulations of a complete aircraft on millionspoints grids on a daily basis, as needed in industry.


Combinations of such streamsurfaces may be built up piecemeal into complete aircraft configurations, and it is shown that the method is sufficiently flexible to allow considerable freedom of choice in the disposition of lift and volume.


We are committed to supporting the complete aircraft life cycle from initial concept to aging aircraft retrofits.


The complete aircraft was modelled using a few modes of vibration, including rigidbody modes.


The KC135 priming operation was limited to the leading edges, while the B52 was a complete aircraft prime.

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 To meet the strict demands for the seabased aircraft during takeoff and landing phase is the most important flight dynamic problem to be solved. One of the main differences between takeoff from the ground and from the deck is that ground effect loses gradually after liftoff from the ground,while it loses suddenly in case of liftoff from the deck. As is known to all, the ground effect has considerable influence on drag, downwash field behind the wing, and specially on lift. The sudden loss of lift may cause... To meet the strict demands for the seabased aircraft during takeoff and landing phase is the most important flight dynamic problem to be solved. One of the main differences between takeoff from the ground and from the deck is that ground effect loses gradually after liftoff from the ground,while it loses suddenly in case of liftoff from the deck. As is known to all, the ground effect has considerable influence on drag, downwash field behind the wing, and specially on lift. The sudden loss of lift may cause so called "sink" for seabased aircraft at the instant of liftoff from the deck,which may cause safe problem for aircraft. Two important aspects are included in this thesis:1. A. synthetic method is presented here to estimate ground effects on aerodynamic forces and moments of a complete aircraft.2. The change of takeoff characteristics, especially the sinkage, caused by sudden loss of ground effect has been studied and a numerical method concerned has been developed.  众所周知,地面效应(以下简称“地效”)对近地飞行时飞机的迎角、升力、阻力和洗流场都有明显影响,而尤以升力效应对起飞特性的影响最为严重。舰载机在飞离甲板瞬间地效升力突然损失,可能导致“下沉”现象,直接影响到飞机的安全。本文的工作包括两个主要方面:1.在总结现有文献的基础上,提出在不同离陆高度时全机气动参数的计算方法。2.研究舰载机在飞离甲板瞬间因突然失去地效而导致起飞特性的变化,特别是下沉问题。算例表明,地效使得甲板起飞和地面起飞特性有明显区别,是舰载机设计中必须考虑的重要问题。  This paper introduces three parts.The study on the hingemoment balance technoiogy of half model of complete aircraft.Thedesign,research of seven sets of hinge moment balances and four sets ofspecial calibration devices and is tatic calibration of balance.The lastpart is its applications to BOEING 707 model hinge moment test in FD09 Lowspeed tunnel.Tests prove that,the wind tunnel test technoiogy of applying fivesets of hinge moment balances simultaneously on a single model effectively saves testing... This paper introduces three parts.The study on the hingemoment balance technoiogy of half model of complete aircraft.Thedesign,research of seven sets of hinge moment balances and four sets ofspecial calibration devices and is tatic calibration of balance.The lastpart is its applications to BOEING 707 model hinge moment test in FD09 Lowspeed tunnel.Tests prove that,the wind tunnel test technoiogy of applying fivesets of hinge moment balances simultaneously on a single model effectively saves testing time and cost,with test efficiency improved.Testresults prove that, the design of hinge moment balance group conformswith the requirements of hinge moment test on half model in Lowspeedwind tunnel,with static calibration accuracy higher and dynamic calibration results reliable.The resuits from wind tunnel tests are highly appreciated by departments concerned.By comparing the experimental data from FD09 windtunnei with that from documents,the reliabilty degree of the laterrefrence is,recognized,so this technology is ofimportant refrence valueto the accuracy improvement of hinge moment tests of half model indomestic Lowspeed wind tunneis.  本文介绍了全机半模型铰链力矩天平技术的研究;介绍了七台铰链力矩天平和四套专用校正装置的设计和研制;天平的静校及其在 FD09低速风洞进行的波音707模型的铰链力矩实验。通过实验证明:在一个模型上同时应用多台铰链力矩天平进行风洞实验的技术,有效地节省了试验时间和经费,提高了风洞实验效率。实验结果表明了铰链力矩天平组的设计符合风洞实验的要求,静校精度较高,动校结果可靠。  The aerodynanic design criteria and design procedures for supercritical wing are established based on the computational aerodynamics. For supercritical airfoil design, the criteria contain (a) sonic plateau pressure distribution at off design condition, (b) retarding trailing edge flow separation, (c) nearzero angle of attack at design condition, and (d) local thickness constraints. For supercritical wing design, the criteria include (a) induced drag minimization under some constraints , (b) meeting stability... The aerodynanic design criteria and design procedures for supercritical wing are established based on the computational aerodynamics. For supercritical airfoil design, the criteria contain (a) sonic plateau pressure distribution at off design condition, (b) retarding trailing edge flow separation, (c) nearzero angle of attack at design condition, and (d) local thickness constraints. For supercritical wing design, the criteria include (a) induced drag minimization under some constraints , (b) meeting stability requirement, (c) isobar pattern on the upper wing surface, and (d) cosidering elastic deformation of two wing. The supercritical wing design procedures can be divided into the phases, i.e. configuration design phase and aerodynamic efficiency optimization phase. The latter contains four steps: (a) basic airfoil design, (b) initial wing design, (c) cruise wing shape design, and (d) jig wing shape design. As a design example, a supercritical wing is designed and is tested in wind tunnel. The result indicates that the complete aircraft with the supercritical wing designed according to the present method has 12% higher cruise efficiency then a typical commercial airliner, although the former wing is 14% thicker than the latter one, which shows the present aerodynamic design method for supercritical wing is practically effective.  以计算空气动力学为基础,提出超临界机翼的气动设计准则和设计流程。翼型设计准则是:非设计状态音速区压力平坦;延迟后缘分离;设计状态迎角接近于零和局部最小厚度约束等。机翼设计准则是:在约束条件下诱阻最小;满足纵向稳定性要求;上翼面等压线型态和考虑结构弹性变形等。设计过程可分为两个阶段,即总体优化和机翼气动设计优化。后者的步骤是基本翼型设计、初始机翼外形设计、机翼巡航外形设计和机翼型架外形设计。对设计实例进行风洞试验后表明:尽管新机翼的平均厚度比某干线运输机厚14％,但安装该机翼的干线运输机巡航效率仍比前者高12％。   << 更多相关文摘 
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