數值不穩定性 的英文怎麼說
中文拼音 [shǔzhíbùwěndìngxìng]
數值不穩定性
英文
numerical instability- 數 : 數副詞(屢次) frequently; repeatedly
- 不 : 名詞[書面語] (剁物所用的木墩) a block of wood
- 穩 : 形容詞1 (穩定; 穩當) steady; stable; firm 2 (穩重) steady; staid; sedate 3 (穩妥) sure; rel...
- 定 : Ⅰ形容詞1 (平靜; 穩定) calm; stable 2 (已經確定的; 不改變的) fixed; settled; established Ⅱ動詞...
- 性 : Ⅰ名詞1 (性格) nature; character; disposition 2 (性能; 性質) property; quality 3 (性別) sex ...
- 數值 : numerical value; numerial number; figure; magnitude; value數值表 numerical tabular; 數值天氣預報 ...
- 穩定性 : antiwhip
- 穩定 : 1 (使穩定) stabilize; steady 2 (穩固安定) stable; steady 3 (物質的性能不易改變的作用) stabi...
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This thesis tries to solve the problems in the design and construction of jinping cascade 2 hydropower station. a typical section is selected to analysis seepage, seepage control and fem numerical simulation. the influence of different plans of excavation and support on seepage field of subsurface water and stability of adjoining rock are studied. the homologous support pattern is suggested according to the research results
本文就錦屏二級水電站(一期)深埋長隧洞的設計和施工中面臨的一些問題,選取隧洞的一個典型斷面進行滲流、滲控分析和開挖及支護的有限元數值模擬,從而就深埋隧洞不同的開挖及支護方式對地下水滲流場及圍巖穩定性的影響和所應採取的支護措施等方面進行了探索、研究。Abstract : based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high - temperature rutting test, low - temperature bending test and controlled stress flexural fatigue test are used to study the performance of asphalt mixtures modified by epoxy resin including high - temperature stability, low - temperature cracking - resistance, and fatigue cracking - resistance, which are served to evaluate the modification effect of epoxy resin of different contents. with the addition of epoxy resin, all the three performances are improved greatly. however, when the amount of epoxy resin added is over a certain value, the modification effect will be stable with no extra benefit detected. finally, in terms of the properties of the three respects, 20 ?, 30 ?, 30 ? are given separately as the proposal adding contents
文摘:在分析鋼橋面鋪裝層主要病害和特殊工作環境的前提下,分別採用高溫車轍試驗、低溫小梁彎曲試驗和控制應力小梁彎拉疲勞試驗,研究了不同環氧樹脂摻量下的環氧樹脂改性瀝青混合料的高溫穩定性、低溫抗裂性和抗疲勞性能.試驗結果表明:環氧樹脂對這3個方面都有很大的改進效果,但改性效果和樹脂的添加量並不是一個無限遞增的關系,當添加量超過一定數值以後,改性的效果將趨于平穩.最後就高溫、低溫、疲勞3個方面分別提出環氧樹脂添加量為20 ? , 30 ? , 30 ?的建議值Based on the analysis of the main failures discovered in pavement on steel deck plate and the demanding service condition of the pavement on steel deck, high - temperature rutting test, low - temperature bending test and controlled stress flexural fatigue test are used to study the performance of asphalt mixtures modified by epoxy resin including high - temperature stability, low - temperature cracking - resistance, and fatigue cracking - resistance, which are served to evaluate the modification effect of epoxy resin of different contents. with the addition of epoxy resin, all the three performances are improved greatly. however, when the amount of epoxy resin added is over a certain value, the modification effect will be stable with no extra benefit detected. finally, in terms of the properties of the three respects, 20 ?, 30 ?, 30 ? are given separately as the proposal adding contents
在分析鋼橋面鋪裝層主要病害和特殊工作環境的前提下,分別採用高溫車轍試驗、低溫小梁彎曲試驗和控制應力小梁彎拉疲勞試驗,研究了不同環氧樹脂摻量下的環氧樹脂改性瀝青混合料的高溫穩定性、低溫抗裂性和抗疲勞性能.試驗結果表明:環氧樹脂對這3個方面都有很大的改進效果,但改性效果和樹脂的添加量並不是一個無限遞增的關系,當添加量超過一定數值以後,改性的效果將趨于平穩.最後就高溫、低溫、疲勞3個方面分別提出環氧樹脂添加量為20 ? , 30 ? , 30 ?的建議值The earth crust activity of different geotectonic elements could he estimated with the fracture fractal dimension
利用斷裂尺度分佈的分形維數值的大小,可以定性判斷不同大地構造單元的地殼穩定性。A recommend value of appropriate roadbed height is put forward according to the sand dune type and the highway grade, make investigation to the sand harm and other problems of built highways in desert areas gathering the related materials of present day highways, and then make comprehensive and systematic statistics to related data and racious factors which affect the roadbed height ; analy the suitable roadbed height for the windblown sand drift passes through smoothly according to the open country windblown sand field test ; test and verify the outcome according to indoor wind tunnel test ; finally a appropriate recommend roadbed height value will be put forward for different grade highways in different areas, which is according to the analysis of roadbed stability the roadbed height economic analysis and different use requirement to different grade highways
收集現有沙漠公路的有關資料,對全國已建沙漠公路進行沙害及其他病害調查,對相關數據和影響沙漠公路路基高度的各種因素進行綜合系統地統計分析;通過野外風沙流場測定,分析適宜風沙流順利通過的路基高度;通過室內風洞試驗進行驗證;結合路基穩定性分析、路基高度的經濟性分析,考慮不同等級公路的使用要求,最終提出不同地區不同等級沙漠公路路基填土高度的合理高度建議值。High resolution eulerian adaptive algorithmfor interfaces instability
界面不穩定性的自適應歐拉數值計算The water quality respond relation of input - output measurements are established by systematic theory in this paper. according to the peculiarity of hydrology and the necessity of water quality inverse problem the multi - parameter inverse problem model based on ordinary differential equation is developed. the existence and uniqueness of the solution of the ordinary differential equation about two parameters or multi - parameter are to be proved. the unstability depending on errors between monitoring data and interpolation approximate data are analyzed and demonstrated. cubic spline interpolation function, the least two multiply and positive rule method are conjoined for obtained solution of multi - parameter. the results from this algorithm indicats its efficient to the multi - parameter identification in water quality modeling
本文應用系統理論,建立了水質多參數輸入輸出之間的響應關系;根據河流水文水質變化特點和參數反問題的需求,建立了水質常微分方程多參數反問題模型.根據常微分方程參數反問題的數學理論,作者給出了兩參數和多參數水質常微分方程反問題的解的存在性、唯一性的理論證明過程和結論;還針對水質現有監測資料的測驗誤差和插值近似計算誤差造成參數反問題的不穩定性,將三次樣條插值函數、超定方程最小二乘法和正則化演算法有機地結合使用,成功地給出了水質參數反問題的穩定化演算法.最後給出了應用計算結果Finally, compared with the 2d result, the synthetic jet that 3d numerical simulated has a definite direction. the 3d result, however, has a much smaller fluctuation owing to the span - wise instability which created a breakup of coherent vertical structure into smaller scales, it therefore compares more favorably with the measured data in tests
三、三維模擬結果顯示合成射流的方向性極佳,與二維模擬相比較,三維數值模擬的速度波動較二維模擬要小,旋渦的相干結構衰弱,這是因為三維模擬考慮了流動的橫向不穩定性,這更加接近實際情況。In this article, some results of the theoretical derivation and computational campaign performed to study the fluid instabilities in convergent geometry are presented
本論文通過理論分析和數值模擬方法,對收縮幾何中的一些流體不穩定性問題進行了研究。Abstract : the stability of the nonlinear comput ation is important in numerical weather prediction. in this paper, the concept, phe n omena and mechanism of nonlinear computational instability of the nonlinear evol ution equations in numerical weather prediction are discussed. an effective schem e, the square conservation shceme, is presented
文摘:簡述了數值天氣預報問題中非線性發展方程的非線性計算不穩定性的含義、數值計算現象以及計算不穩定產生的機理,給出了克服非線性計算不穩定的一個有效方法? ?平方守恆格式。This filter is a combination of adaptive ud decomposition kalman filter with quad method. it use quad method to detect and correct the gross errors in observations, use ud decomposition technique to improve computation precision and overcome the instability of filter caused by instability of values, when divergence of kalman filter had been detected, an adaptive filter is employed to adjust the prediction error covariance matrix
該法用擬準檢定法準確地探測和修正量測方程中存在的粗差;用ud分解演算法改進了計算精度,克服了由於數值不穩定帶來濾波的不穩定性;當判斷濾波器發散后,則啟用sage自適應濾波器,調整預測誤差方差,以克服濾波器的發散。The two - dimensional axisymmetric subsonic - transonic - supersonic flow in an experimental arcjet thruster is simulated numerically using flux vector splitting method. the profiles of density, velocity, temperature, pressure and mach number can be obtained by the computation. the computation grid and some computed results are given here. the test equipment such as power supply system, ignition system, propellant supply system, arcjet thruster, thrust measuring device and vacuum system are introduced briefly. some working phenomena of the arcjet are observed and discussed. three different kinds of instability appeared in the process of the experiments. except some important parameters are measured, it is found that the operating stability of argon is better than that of nitrogen
對一實驗電弧加熱式發動機二維軸對稱亞跨超音速流動進行了數值模擬,所採用的方法是矢通量分裂演算法.通過計算可以得出密度、速度、溫度、壓力和馬赫數的分佈.給出了計算所使用的網格和一些計算結果.簡要介紹了實驗所使用的設備,如電源系統、點火系統、推進劑供給系統、電弧加熱式發動機、推力測量裝置和真空系統.對所觀察到的一些工作現象進行了討論.有三種不同的不穩定性出現于實驗過程.除了所測量的一些重要參數,通過實驗發現氬比氮工作更穩定The 3d simulation result shows characteristics as well as creating, developing and dissipation process of the microjet. the results show good agreement with experimental results. the numerical study reveals the spanwise instability of vortex pairs, resulting in the breakdown of the coherent vortex structure
三維微射流流場的數值模擬再現了實驗所觀察到的旋渦對的生成、發展及其相干性的消失過程;揭示了旋渦對沿展向的不穩定性是旋渦對相干性消失的主要原因。Secondly, the author independently develops a sph code. sod shock tube and strong shock are calculated as examples to test the code, and as well 2d r - t instability is simulated. sph is a fully lagrange gridless numeric technique
另一方面作者獨立開發了sph程序,並以sod激波、強激波作為算例檢驗了程序,同時實現了r - t不穩定性的二維數值模擬。Numerical results are consistent with that of sandia laboratory experiment and agree with that of cth code too. an adaptive mesh refinement under 2d euler structure grid for multi - fluid flow is developed for resolving richtmyer - meshkov, rayleigh - taylor and helmholtz multi - fluid instabilities, and the high resolution interface properties can be obtained
數值模擬多介質流體richtmyer - meshkov , rayleigh - taylor , helmholtz界面不穩定性,用levelset函數定義euler坐標系中界面附近網格自適應判據,使得網格剖分更加合理,既能提高計算精度又能節省計算時間。Computational simulations are the main method to study fluid instability during an implosion in inertial confinement fusion
數值模擬是慣性約束聚變內爆中流體不穩定性研究的主要方法。The key point in the research of the instability is how to capture exactly the movement of the contact interface
在界面不穩定性的數值研究中,最核心的當是運動界面的精確描述,正是由於這?需要使得虛擬流動界面捕捉( ghostfluidmethod )方法得以充分發展。Furthermore, numerical algorithms used to solve the linear system are introduced. next, after briefly discussing several causes of the late - time instability of the tdie solvers, a novel viewpoint about the instability is proposed. the marching - on - in - time algorithm ( mot ) is described and some temporal bases are discussed
其次,在簡要分析了引起時域積分方程( tdie )時間步進演算法求解的后時不穩定性問題的幾個原因后,指出引起時域積分方程時間步進演算法的后時不穩定性的主要原因是離散tdie時採用了不精確的數值計算方法和不恰當的近似。Through static and dynamic numerical analyses of geometrically symmetric and asymmetric 3pbs, the conclusion is drawn : asymmetrical dynamic stress - strain field causes the crack expanding instability of geometrically asymmetric sample but not static condition
?通過以上幾何對稱及非對稱3pbs模型的靜態、動態數值分析,得出結論:幾何非對稱試件裂紋後期擴展的不穩定性是由非對稱的動態應力應變場引起,與靜態條件無關。On the basis of producing the mathematical model of calculating the induced currents on the passive feedback coils, the distribution and variation of the induced currents and the eddy currents magnetic field are given by numerical calculation. these conclusions are necessary to study the vertical unstability of plasma and design the coils
在建立求解被動導電板感應電流數學模型的基礎上,通過數值計算,給出了感應電流的分佈和變化情況,同時對渦流磁場的分佈和變化也給出詳細的計算結果,這些結論對研究等離子體垂直不穩定性和線圈的設計是必需的。分享友人