渦流常數 的英文怎麼說
中文拼音 [guōliúchángshǔ]
渦流常數
英文
eddy current constant-
By comparing the dry plate pressures drop and distributions of velocities simulated on single valve with those of double valves, it was found that there was intense turbulence in the flow fields around fixed - valve, there were eddy areas between valve side orifices and tray wall, there were eddies above the valves too, these led to the complex behaviors of gas perforating valve, these had a great effect on the gas - liquid mass transfer process. at the same time, in order to prevent the disadvantageous effect of gas between one valve with another on the gas - liquid mass transfer, it was very effective to change the fields of gas perforating valve by folding the edges of valve
通過對數值模擬得出的單閥和雙閥塔板的干板壓降及流場速度分佈分析對比后發現，固定閥周圍流場存在較強的湍動，閥側孔與塔板壁面區域以及閥體的上方空間存在明顯的渦流區，使氣體穿閥后的行為變得復雜，並對氣液傳質過程產生重大影響；模擬結果表明，為防止和削弱固定閥間的對沖造成的「死區」對傳質帶來的不利影響，通過折邊來改變氣體的氣路是非常有效的，模擬值與實驗值基本得到吻合。Eddy - current sensor conversion circuit consist amplification circuit, band - pass filter circuit, demodulation circuit, differentiation phase and data sampling circuit. these circuits are used to convert the test signal of eddy - current sensor to discrete signal tend to process. the microprocessor system that formed of dsp chip is used to data fitting of test system, data displaying and data communicating with personal computer, etc. the interference questions of hardware design and the measure of eliminating interference signal in the subject are introduced in the last of this chapter
硬體電路的設計主要分三大部分來實現：激勵源電路部分，由分頻電路和頻率合成電路組成，產生頻率穩定的激勵信號以確保檢測任務的正常進行；傳感器變換電路部分，由放大電路、濾波電路、檢波電路、鑒相電路和數據採集電路組成，主要將電渦流傳感器檢測線圈檢測到的信號變換成只含有被測信息的離散信號，易於后續電路處理；由dsp晶元構成的微處理系統，主要完成檢測系統的數據擬合、顯示及與主機通信等功能。Based on an engineering background, through numerical simulation of the flow field in the hp turbine of the energy efficient engine ( e3 ), the article research the unsteady flow in a transonic turbine stage, the unsteady phenomena in the stage include the shockwave, wake, shedding vortex, endwall vortex, passage vortex and leakage vortex, etc. there are two shockwaves generated on the vane the tailing edge, one on suction side is named moving shockwave, and name another on pressure side steady shockwave
本文首先對于研究的意義和國內外研究的現狀做了簡要的介紹，再從某工程背景出發，通過對e3發動機高壓渦輪內流場的數值模擬，研究了干涉的周期性的問題，以及渦輪級內常見的非定常現象：激波、尾跡、脫落渦、根腳渦、通道渦、漏流渦。導向器尾緣會出現兩道激波，在吸力面的激波可稱為「運動」激波，壓力面的激波可稱為「定常」激波。In the second part, firstly, the mathematical model for predicting hydrodynamic characteristics of varivec propeller under steady or unsteady condition are present, based on the general propeller lifting - surface theory, potential flow theory and green theorem. then, theoretical calculation methods for predicting hydrodynamic characteristics of varivec propeller designed above paragraphs are present, based on the finite basic solution method, the unsteady vortex lattice method and hess - smith method
在理論計算部分，本文首先基於常規螺旋槳升力面理論、勢流理論和格林定理建立了定常和非定常狀態下全方向推進器水動力性能計算的數學模型，然後利用有限基本解法、非定常渦格法和赫斯?史密斯方法對全方向推進器定常和非定常狀態下的數學模型進行了數值離散，接下來針對前面所設計的全方位推進器進行了數值預報。The results indicated that the generation of trailing - vortex of downstream adjacent vanes could be restrained effectively by upstream wake when the passing frequency and the amplitude of wake defect satisfy some conditions, associated with a significant enhancement of time - averaged aerodynamic performances : loss coefficient reducing 40. 2 % and the ratio of loading coefficient and loss coefficient increasing 93 %
研究表明：滿足一定通過頻率和虧損幅值條件的尾跡能夠有效抑制下游相鄰葉排尾緣渦的生成，達到控制或是推遲附面層非定常分離的目的，從而使得流場時均性能大幅度的提高，損失系數降低了40 . 2 % ，功損比增加93 % 。Numerical simulation of unsteady vortex in the wake of cascade flow
葉柵流場尾跡中非定常渦系的數值模擬Based on the vibration test in yantan hydropower house, in this paper the author adopt les method which belong to three dimensions unsteady turbulent flow numerical analysis to simulate vibration resource characteristics of hydrogenerator set, a harmonic vibration model of powerhouse substructure is put forward to carry out firstly a precise modal analysis and dynamic response analysis for generator floor. the numerical calculation results agree well with the surveyed data in situ
本文結合巖灘水電站廠房振動的試驗研究，採用非定常湍流數值分析的大渦模擬方法進行混流機組水力振動振源模擬；提出一種水電站廠房下部結構簡諧振動模型，首次進行了發電機層樓板結構的精確模態分析和水力激振荷載下的動力響應分析，各項計算結果與實測數據吻合良好。Based on t213 and other observational datasets, a severe heavy rain occurred in changjiang - huaihe basins during 4 - 5 july 2003 is studied. the primary diagnostic analyses show that double or single block is the characteristics of the macroscale circulation in this rainfall process. the strong conflict of warm and cold mass, mesoscale convergence on meiyu front, shear line, and stably maintaining of high and low jets make for the rainfall
本文採用地面高空常規資料，每6h一次的降水資料，以及t213數值預報資料，對2003年7月4 - 5日發生在江淮地區的一次梅雨鋒暴雨過程的影響系統及其可能機制進行了初步的診斷分析，發現，高緯雙阻、單阻形勢是這次暴雨過程發生的大尺度環流特徵；冷暖空氣的激烈交鋒、梅雨鋒上的中尺度輻合線、 700hpa 、 850hpa上的低渦、切變線以及穩定維持的高低空急流是導致這場暴雨的直接影響系統；該地區維持一個高能、飽和、潛在不穩定的環境，有利於特大暴雨的產生和維持。According to the definition of stream function and vorticity, this article theoretically derives a formulation of definite solution problems for resolving two dimensional flow, which is different from the usual formulation, from the stream function - vorticity n - s equation
摘要從定常二維平面流動的流函數渦量型n - s方程出發，從理論上推導出一種不同於通常提法的二維平面流動的定解提法。Therefore, this paper studies three kindsvalves such like bufferfly valve, brake valve and ball valve, with the numerical simulation method by cfx which is often used to simulate the fluid. by the simulation of three kinds of valves, we can kown dynamic characteristic of them. in this paper, i not only simulate for three kinds of valves, but also analyse cause of flow - noise and give respectively mathematical model of main noise sources in piping system such as pupm and valve
本文通過cfx軟體，用數值模擬的方法，對海水管路系統中常見的三種閥門（蝶閥、閘閥、球閥）流動特性及噪聲進行了模擬分析，闡明閥門噪聲產生的機理，建立了泵和閥門等噪聲源的數學模型，並對管路系統中涉及到的邊界條件做了適當的處理，分析了閥門下游的渦聲。Numerical simulation by cfd was carried out to understand the hot current behavior in a tunnel with longitudinal ventilation. it becomes clear that fire source modeling is very important because the hot current behavior is strongly affected by the fire source position and is sensitive to methods in the modeling of the fire source. the flame area which has developed from the fire source is an area of chemical reaction caused by combustion. even if grids in the vicinity of the fire source are made fine, it was difficult to simulate the heat generation area with consideration to this chemical reaction through using a method for setting the heat release rate simply on the fire source surface. therefore, we proposed a method adopting the knowledge on flame shape under the longitudinal ventilation and incorporating it into numerical simulation and it showed a good agreement with the experimental results. it was shown through experiments in a tunnel with longitudinal ventilation that the hot current developed toward the tunnel center downwind from the fire source near a wall. the cause was investigated by numerical simulation and it became clear from the results that the spiral air by the fire plume created a vortex in the crevice between the wall and the plume
運用cfd進行數字模擬，以了解縱向通風隧道內熱煙氣流的特性.通過模擬發現對火源進行模擬非常重要，熱煙氣流特性受火源位置的影響很大，並且對火源模擬方法很敏感.火源生成的火焰區是燃燒引起的化學反應區域.即使火源附近的木垛排列完好，也很難在考慮這些化學反應條件下模擬熱生成區域.建議考慮縱向通風隧道內火焰形狀並對它進行數字模擬.模擬結果與試驗結果非常吻合.試驗證明，在縱向通風隧道內，熱煙氣流從靠近墻體火源處順風向隧道中心蔓延.數字模擬結果發現，火災羽流造成的螺旋上升空氣會在墻體和羽流之間形成一個渦流區Abstract : numerical simulation by cfd was carried out to understand the hot current behavior in a tunnel with longitudinal ventilation. it becomes clear that fire source modeling is very important because the hot current behavior is strongly affected by the fire source position and is sensitive to methods in the modeling of the fire source. the flame area which has developed from the fire source is an area of chemical reaction caused by combustion. even if grids in the vicinity of the fire source are made fine, it was difficult to simulate the heat generation area with consideration to this chemical reaction through using a method for setting the heat release rate simply on the fire source surface. therefore, we proposed a method adopting the knowledge on flame shape under the longitudinal ventilation and incorporating it into numerical simulation and it showed a good agreement with the experimental results. it was shown through experiments in a tunnel with longitudinal ventilation that the hot current developed toward the tunnel center downwind from the fire source near a wall. the cause was investigated by numerical simulation and it became clear from the results that the spiral air by the fire plume created a vortex in the crevice between the wall and the plume
文摘:運用cfd進行數字模擬，以了解縱向通風隧道內熱煙氣流的特性.通過模擬發現對火源進行模擬非常重要，熱煙氣流特性受火源位置的影響很大，並且對火源模擬方法很敏感.火源生成的火焰區是燃燒引起的化學反應區域.即使火源附近的木垛排列完好，也很難在考慮這些化學反應條件下模擬熱生成區域.建議考慮縱向通風隧道內火焰形狀並對它進行數字模擬.模擬結果與試驗結果非常吻合.試驗證明，在縱向通風隧道內，熱煙氣流從靠近墻體火源處順風向隧道中心蔓延.數字模擬結果發現，火災羽流造成的螺旋上升空氣會在墻體和羽流之間形成一個渦流區Numerical simulation on unsteady flow with turbulence intensity effects in a turbine stage
渦輪級內湍流度影響的非定常數值模擬The first diagnostic analyses show that the heavy rainfalls are produced together by vortex, shear line and upper and lower jets, meiyu front. the condition of high energy, saturation, potential instability is propitious to the form and maintenance of heavy rainfall. the result of numerical simulation by mm5 model shows that heavy. rainfall has close relation with meso - scale vortex pole and strong convection
採用ncep全球譜模式和常規觀測資料對「 03 . 7 」江淮地區的兩次暴雨過程的影響系統及其可能機制進行了初步診斷分析，發現梅雨暴雨是受低槽、低渦、切變線、高、低空急流和梅雨鋒區共同影響造成的，該地區維持高能、飽和、潛在不穩定的環境，有利於暴雨的產生中尺度數值模式（ mm5 ）模擬結果表明梅雨暴雨與中尺度渦柱、強對流運動密切相關。The paper researches the transient time precision and the following problem of the results developing with time for 2 - d high order blocking and matched method, at the same time, anlysing the stability of high order methods including boundary conditions. the results show that the domain decomposition and matched method using high order method can follow the time developing solution of taylor problem well, the computation result of the flow over a single or two tandem arranging circular cylinder agree the experiment and others " results well, moreover, the panting results of lift and drag coefficient are better than others
本文利用高精度分塊耦合求解方法，對其瞬態時間精度和非定常時間發展解的跟隨性問題進行了研究，同時也對包含邊界條件的線法高精度格式的穩定性也作了分析，研究結果表明高精度的分塊耦合求解方法可以很好地跟隨taylor問題的時間發展解，與單圓柱繞流和雙圓柱繞流的實驗結果比較以及他人結果比較符合很好，對升阻力系數在渦脫落時的脈動問題的結果優於他人結果。Its warming was the higher in china, ( 5 ) the current atmosphere circulation anomaly is the current factor influenced the winter air temperature in the north - east china, and it includes siberian high anomaly, the east asian trough anomaly, the acreage of polar vortex anomaly, the asian winter monsoon anomaly and the anomaly of the west - wind circulation in east - asian
（ 4 ）東北地區冬季增暖趨勢與中國大部分地區是一致的，是增暖最顯著的地區之一。 （ 5 ）影響東北冬季氣溫異常的同期因子是環流異常，它包括西伯利亞高壓、東亞大槽、東亞冬季風、極渦面積、東亞西風環流指數等的異常。For shutters, the results show : 1 ) according to the formula p =, the theoretical value of is calculated by the effective velocity of the flow, and its engineering value is calculated by the arriving velocity of the flow, the relationship between the theoretical value of and its engineering value is 2 ) the smaller value of declining angle will result in the smaller pressure loss and smaller outlet velocities. as a result, the declining angle of 30 擄 or less is recommended in some places which need small wind velocity, such as broadcasting studio and library, and the declining angle of 45 擄 or less is recommended in places which need big wind velocity, such as cinema and office ; 3 ) the larger value of ratio between the wide of the shutter b and the space between two boards h ( b / h ) will result in the larger pressure loss and smaller outlet velocities. the range of b / h from 0. 8 to 2. 0 and the optimum value 1. 2 is recommended ; 4 ) the range of b from 10 mm to 50 nun and the optimum value 40 mm is recommended ; 5 ) the proper thickness of the boards 8 of the shutters is 1. 5 mm ; 6 ) cuneiform boards should replace the rectangle inlet boards of the shutters in order to obtain better ventilation
數值模擬採用fluent軟體，計算結果用excel進行處理，通過對大量數值工況進行數值模擬計算，結果表明：對于單側百葉風口，計算表明： 1 ）對于公式p = （ ~ 2 ） 2 ，的理論計算值中定義為流體流經百葉風口內部時的速度，即有效速度，而工程上常使用流體的來流速度來計算，計算表明，的理論計算值與工程應用值的關系為（ _ （理論） ） （ _ （工程） ） = 0 . 813 ； 2 ）當來流速度一定時，擋板傾斜角度越小，壓力損失越小、出口速度越小；因此在要求進口風速比較小的場所，如播音室、圖書館等，宜採用擋板角度30的百葉風口；在要求進口風速比較大的場所，如電影院、辦公室等，百葉擋板的角度應選45 ； 3 ）當來流速度一定時，百葉擋板的擋板寬度b與擋板間距h的比值b h越大，壓力損失越大，出口速度越小，計算表明，鑒于壓力損失、出口風速、板間形成渦流區的大小，百葉擋板的b h值取0 . 8到2 . 0之間， b h = 1 . 2為最佳值； 4 ）當來流速度一定時，在計算的條件下，當百葉擋板寬度b = 40mm時，百葉擋板的阻力系數最小，考慮到渦流區等的影響，建議選用10mm b 50mm的百葉擋板；西安建築科技大學碩士學位論文5 ）百葉擋板的厚度取為1 . sinln為好; 6 ）百葉擋板的入口側可選用具有傾斜度的楔形擋板來代替矩形擋板，利用其較好的導流作用，可得到更好的出流效果。Numerical simulation of the unsteady flow in a transonic turbine stage is still a hard work for cfd researcher
渦輪級內的非定常流場數值模擬是現階段計算流體力學研究的重要領域，也是研究的難點。A two - dimensional navier - stokes equation was solved to predict the unsteady, multipassage flow and temperature fields with hot streak in turbine inlet
摘要通過求解二維n - s方程對多通道渦輪級進口有溫度畸變時的流場和溫度場進行了非定常數值模擬。Then virtual dielectric constant method is adopted to calculate the electric field distribution with floating electrodes, and equivalent conductance rate method is adopted to calculate the electric field distribution with surface filth or local puncture in the insulator, furthermore the value scope of virtual conductance rate and equivalent conductance rate are discussed and some useful results are got. for the solution of vortex loss of silicon steel sheets concerning current transformer, the h solution has also been put forward rather than traditional a ? ( p method in order to reduce calculation load
採用虛擬介電常數法計算絕緣子存在懸浮導體的電場分佈，採用等效電導率法計算絕緣子存在表面污穢或局部擊穿情況下的電場分佈。對虛擬介電常數和等效電導率的取值范圍進行了討論，得出了一些有用的結論。對于電流互感器硅鋼片渦流損耗的計算，本文提出了不同於傳統的a -方法的h求解辦法，從而大大簡化了計算。分享友人