邊界層動量 的英文怎麼說

中文拼音 [biānjiècéngdòngliáng]
邊界層動量 英文
momentum thickness of boundary layer
  • : 邊Ⅰ名詞1 (幾何圖形上夾成角的直線或圍成多邊形的線段) side; section 2 (邊緣) edge; margin; oute...
  • : 名詞1 (相交的地方; 劃分的界限) boundary 2 (一定的范圍) scope; extent 3 (按職業、工作或性別等...
  • : i 量詞1 (用於重疊、積累的東西 如樓層、階層、地層) storey; tier; stratum 2 (用於可以分項分步的...
  • : 量動1. (度量) measure 2. (估量) estimate; size up
  • 邊界 : boundary; frontier; border; borderline; edge range line; periphery
  1. A one - dimensional oceanic mixed layer model with the m - y level - 2. 5 turbulence closure schemes is employed. the rate of energy loss by breaking waves is estimated by parameterization and incorporated into the model as a source of turbulence kinetic energy ( tke ) by modifying the existing surface boundary condition of tke equation. the velocity field and turbulence energy budget are calculated under different forcing conditions ( the results given below are for a wind speed of 20 m / s. )

    採用一維2 . 5階湍封閉混合模式,根據參數化方法對波浪破碎導致的能耗散率進行了估計,通過改變湍能方程的上條件引入波浪破碎對湍能生成的影響,計算了不同風應力強迫下的混合流場結構和湍能收支(下述給出的結果是取風速為20m s得到的) 。
  2. A normal transform is introduced, and there are enough much grids in the region between the critical layer and the wall, where the variation of the disturbance is the quickest. the finite - difference of governing equations with fourth - order accuracy in the normal direction is utilized in full regions including points close the wall, and is very important for accurately discreting equations. the combination of global and local methods is implemented, and a new iterative formula is derived

    對于曲線坐標系下的拋物化穩定性方程,文中發展了求解的高效數值方法:引進法向變換,使得在臨與壁面之間的擾變化最快的區域有更多的法向網格點;導出包含鄰域在內的完全四階精度的法向有限差分格式,這對方程精確離散至關重要;採用全局法和局部法相結合的方法及其新的迭代公式,大大加速收斂並得到更精確的特徵值。
  3. Using the system designed in this thesis work, flow field calibration of the wind tunnel is accomplished, which covers dynamic pressure drop coefficient, dynamic pressure time stability, axial static pressure gradient, boundary layer, and degree of turbulence, etc. boundary layer measuring principle and method are especially described in detail, the relationship between boundary layer thickness, wind speed setting, and the depth of the experimental section is summarized, and finally the calibration data for th e model center zone under specific wind speed are given

    然後利用本文設計的系統完成了落差系數、壓時間穩定姓、軸向靜壓梯度、及湍流度等內容的流場校測。特別對的原理及方法做了較詳盡的敘述,總結出厚度與設定風速、實驗段深度的關系,然後給出模型中心區一定風速下校正數值。
  4. According to non - newtonian fluid mechanics theory and mathematical method, conbined with plunger moving property, the hypothesize fluid is imcompressive, hydraulic radius of flow of liquid in crevice is very little, and it is laminar flow, the flow is treated fixed continuous flow at every instant position of plunger, equation of motion and boundary condition were set up in condition of concentric and eccentric of pump barrel and plunger

    運用非牛頓流體力學理論和數理方法,結合抽油泵柱塞運特點,假設液體為不可壓縮的,液體在縫隙中流的水力半徑很小,呈流流,柱塞在每一位置的瞬間,流做定常流處理,建立了泵筒與柱塞同心和偏心兩種情況下運方程和條件,引入無綱坐標、無綱速度和柱塞與泵筒偏心配合時的縫隙高度,並給出縫隙流流速、流的解析解。
  5. The detailed experimental investigation of the distribution and evolution of the mean velocity profile were executed. the signal of instantaneous velocity, the energy spectra of velocity and wave characteristics in the boundary layer have been analyzed

    對局部加熱的水平平板下表面內的時均速度的演化規律進行了詳細的測,同時對速度脈信號以及速度能譜進行了分析,並對內的波特性進行了研究。
  6. In chapter two, according to n - s equation, considering the couple between liquid and solid, the double - fluid model is used to respectively set up momentum equations of two - phase fluids in condition of basic hypothesis, which are general equations of two - phase fluids. simplifying the equations in boundary layer, the momentum differential equations are required and the boundary conditions are given. in the same time, the simplifying equations and their solutions, in which solid grain satisfies in boundary layer

    第二章依據n - s方程,考慮到液、固之間的相間耦合,在基本假設條件下,採用雙流體模型,分別建立液、固兩相的方程,它是固液兩相流體的一般方程式;對其在流區內進行級比較,得到邊界層動量微分方程並給出其條件,同時也得到固體顆粒在內所滿足的簡化方程及其解的表達式。
  7. Momentum integral equation of turbulent boundary layer on ogree section of spillway dam in considering the gravity and centrifugal force

    考慮重力及離心力的溢流壩反弧段紊流邊界層動量積分方程
  8. In the thesis the low drag - low noise optimization of the vehicle main form design is realized, main accomplishments are as follows. researched the knowledge of drag and flow noise, the parameters of the boundary layer are calculated by the hess - smith method and boundary layer momentum integral method. the calculation of the length of transition zone and change in boundary layer displacement thickness between laminar and turbulent states in the transition is improved, then the drag coefficient and self - noise from the transition zone are calculated as the objective functions of the optimization

    主要研究內容和成果如下:對航行器繞流流場進行分析,深入研究了阻力和流噪聲產生機理,建立了阻力系數和自噪聲的評估數值計算模型;採用物面分佈源匯法和邊界層動量積分法對繞流流場的流體力參數進行計算,改進了轉捩區長度和位移厚度的計算,應用於航行器頭部駐點自噪聲的計算;最後設計了阻力系數和自噪聲數值計算程序模塊。
  9. The dissertation refers to comparatively full literatures in the field of vsc, and the development history and characteristics of vsc are summarized, and the elementary concepts, elementary definitions, elementary properties, elementary principles and design methods are particularly introduced, and the causes of the chattering phenomenon are systematically analysed, and the study status of the chattering phenomenon and the main methods to eliminate the chattering are elaborated. for the deficiencies of traditionary methods, three improved methods are developed, which are improved exponent reaching law solution, variable boundary layer solution and the solution by adding an auxiliary continuous control term. for uncertain linear systems, an adaptive fuzzy integral variable structure control stategy ( afivsc ) is put forward to eliminate the chattering around the sliding plane, which introduces fuzzy logic to soften the non - linear discontinuous sig nal in the control variable and utilizes adaptive theory to adjust output membership function according to how much the uncertainty of the system is

    比較全面地查閱了關于變結構控制理論的文獻,總結了滑模變結構控制的發展歷史和特點,詳細介紹了變結構控制的基本概念、基本定義、基本性質、基本原理以及設計方法;系統分析了變結構控制系統抖振產生的機理,並闡述了國內外目前對抖振問題的研究現狀以及消除抖振的主要方法;針對傳統抑制和消除抖振方法的不足,改進了傳統方法,得到了三種新的消除抖振的方法? ?即改進的指數趨近律法、可變法和附加連續項法;針對不確定性線性系統,在變結構控制策略中引入模糊邏輯和自適應理論來消除滑平面上的抖振,提出了一種自適應模糊積分變結構控制方案( afivsc ) ,利用模糊邏輯來柔化控制中非線性不連續部分,採用自適應理論,根據系統不確定性大小在線調整模糊輸出的隸屬函數,另外,鑒于模糊控制本質上是有靜差的,所以本文選擇了帶積分項的切換函數,由於積分項的存在使系統較正為無靜差系統。
  10. To solve this problem, the method of " sucking - spouting " water has been put forward by lin bingnan, based on the theory of boundary layer control, namely, sucking part of the discharge at the upstream - side of the convex barrier and spouting it at the downstream - side

    林秉南院士提出了兩種方案: 1 、吸、噴水方案,即在(突出山體)的順水面將水流吸走,並在下游面噴水增加水流,以控制迴流尺度。
  11. Based on prandtl ' s momentum transportation, this paper calculates in detail the physical quantities such as eddy viscosities, and ratio of eddy viscosity to motion viscosity, total stresses with respect to relative position in three regions of viscous sub - layer, buffer layer, and main turbulent stream for non - newtonian fluid flowing turbulently in ducts, which according to karman ' s three layer models and measurement of fluid parameters in evaluation apparatus, discusses the influence of polymer drag reduction on flowing properties of non - newton fluid, analyzes quantitatively principle of turbulent reduction phenomenon and condition of increasing reduction rate

    摘要以普蘭德傳遞理論為基礎,按照卡門的三模型,通過室內模擬環道用0號柴油及加入減阻劑在圓管內的流參數的測定,計算了非牛頓型流體管內湍流流內、過渡、湍流中心的渦流粘度,渦流粘度與運粘度比、總應力隨相對位置的變化等定參數,探討了高分子減阻劑對非牛頓流體流特性的影響,對湍流減阻現象的機理與增大減阻率的條件進行了定分析。
  12. Refined grids were utilized in a large - eddy simulation model for obtaining high - resolution planetary boundary data and analyzing surface layer turbulence. simulation results showed that refined meshes reduced turbulent contributions of subgrid scales, sensitivity of simulation results to sgs parameters decreased, and features of the whole boundary layer were explicitly resolved better. results also revealed flux - profile relationship correctly in surface layer and a good agreement of turbulent velocity characters with observation. therefore, it concluded that the les method was able for simulation of surface layer flow and turbulence, and might be used for further applications

    採用加密網格的大渦模式獲取風溫場的高解析度模擬結果,並據以分析近地面大氣的湍流特性。結果表明,較小的網格尺度使次網格湍流貢獻率大為降低,模式計算結果對次網格參數的依賴性減小,整體特徵得到更好的反映。同時,模擬出的近地面廓線關系及湍流速度特徵與實際觀測結果吻合甚好,表明模式具有反映近地面平均運和湍流特性的能力。
  13. By the integral to boundary layer thickness and relative conditions, the momentum integral equation of boundary layer is obtained

    通過對厚度的積分並利用相關條件,得到了邊界層動量積分方程。
  14. In chapter three, the momentum integral equations and their solutions of two - phase fluids in boundary layer are given and the no - disturbance solutions on the surface of vane are required. leading into the disturbance factor of no - dimension and thickness coefficient ks in boundary layer, the numerical method of finite approximation is used to calculate the boundary layer

    第三章給出了固液兩相流泵的邊界層動量積分方程及其解的一般表達式,並得到葉片表面的無擾解;引入了無綱擾因子及厚度系數k _ ,給出了用於計算的有限次逼近的計算方法。
  15. Firstly, based on n - s equation, the momentum differential equation ( contained centrifugal force ) is derived by simplification in boundary layer and then integrates the differential equation over the thickness of the boundary layer, the momentum integral equation is deduced. the dimensionless centrifugal factor is introduced, then the solution of the momentum integral equation is obtained. the dimensionless group is introduced to determined separation of boundary layer

    本文首先根據粘性流體力學的一般方程,通過在內進行級比較,在所限定的范圍內得到了含有離心力的邊界層動量微分方程並給出其滿足的條件,然後對該微分方程在內積分得到離心泵葉輪邊界層動量積分方程,在求解過程中引入了無綱離心因子,並作了相應合理的假設,得出積分方程解的一般表達式,並引入以邊界層動量損失厚度為主要特徵的無綱參數對分離進行評價。
  16. An experimental investigation on the transition in the boundary layer of horizontal plane with and without single two - dimensional roughness elements has been carried out in the wind tunnel. the distribution in normal and stream - wise directions of intensity of t - s wave excited by vibrating beam was measured in every condition. neutral curves were obtained by measuring the growth of the t - s wave at the normal critical location along the stream - wise direction

    在風洞中對水平光滑平板以及加有粗糙元平板的轉捩進行了測與研究,比較了不同情況下平板內由振梁激勵生成的t - s波沿流向和法向強度的分佈規律,得到了相應的振型增長曲線以及中性曲線。
  17. According to the theory of boundary layer and the important of boundary - layer separation point detection of delta wing, the measuring principle and structure scheme of various system alternatives based on mems technology have been discussed, selecting the prototype of better workability. base on the master piece model of micro shear stress sensor

    首先,結合空氣力學的原理,針對三角翼分離點檢測在實現主控制方面的重要性,討論了光學式、電容式和熱敏式微型剪應力傳感器的測原理和結構方案,選取適合加工條件的微型剪應力傳感器樣件。
  18. Wavelengths or scales of surface heterogeneity are less than 20km. simulation results show that cbls do reach a quasi - stationary state correspondent to specified surfaces, after a long enough evolution. in this transition process and after that, horizontal statistics, i. e. mean potential temperature and vertical heat - flux, show profiles little differences to those over homogeneous flat surface. main effect of surface heterogeneity is to increase kinetic energy in cbl and the increase concentrates in the direction of surface heterogeneity. the time of cbl spent to reach its first peak of mean kinetic energy,

    模擬結果表明,在充分長的時間后,達到一種適合於地面條件的準定常態。這種準定常態和向其過渡的過程中,水平平均的廓線性質,如平均位溫廓線垂直熱通廓線等幾乎與平坦均勻地面的結果相同,或差異極小。地面非均勻性的主要作用是使能增大,並以地面非均勻性變化方向的能增加為主。
  19. Abstract : a numerical model and experiments over pmma are used to evaluate the main assumptions used in the theoretical description of a diffusion flame established in a natural boundary layer. flow characteristics ( 2 - d boundary layer ) and surface thermal balance are identified as the critical assumptions to be evaluated. comparison of experiments, numerical results, and theoretical model serve to validate the assumptions leading to the definition of a mass transfer number but establish the need to model all three - dimensional features of the flow

    文摘:對pmma進行數字模擬和試驗,對描述自然擴散火焰理論的假設進行評價.我們把流特性(二維)和表面熱平衡作為評價的關鍵假設.試驗、數字模擬和理論模型證實了對質傳遞數值定義的假設是正確的,但研究也表明,有必要對流特性進行三維模擬
  20. Results from this investigation show that the loss generation within the coolant holes is substantial and that ejection into regions of low static pressure increases the loss per unit coolant mass flow. the results also reveal strong interactions between endwall coolant ejection and secondary flow in the blade passage. the secondary flow has a strong influence on coolant trajectories and coolant ejection delays the three - dimensional separation of the inlet boundary layer on the endwall, chang the secondary flow and reduces its associated losses

    本文的研究成果顯示,冷卻孔內產生的損失是主要的,並且低靜壓區域的冷空氣噴射會增加單位冷空氣質流的消耗;噴射的冷空氣與葉柵端壁流場之間有強烈的相互作用;二次流對冷卻空氣的流軌跡有較強的影響;冷空氣噴射能延緩端壁入口的三維分離、改變二次流從而減少其相關損耗。
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