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flux density 【物理學】通量密度。

flux gate

By analyzing and processing bountiful experimental data collected in short time , the curves of temperature variation of fast transient nucleate boiling are then drawn with wavelet analysis theory . also by setting up the mathematical model and applying the temperature variation curves to this mathematical model , heat flux density can be resolved 利用數學方法? ?小波理論成功分離了快速數據采集系統中溫度信號和噪音信號,得到瞬態沸騰的溫度變化曲線;并通過建立數學模型、利用實驗所得的溫度變化曲線,求解出瞬態熱流密度。

According to magnetic medium following the theories , such as ferromagnetics , electromagnetic field , electrodynamics and so on , and linking the characteristics of driving of giant magnetostrictive materials , a control model and driving approach , which one to one correspondence with magnetostriction , are founded . the theory analysis and experimental study demonstrate that the control accuracy of giant magnetostrictive materials can be effectively improved , if using this control model and control approach of giant magnetostriction materials on account of flux density 通過理論分析和實驗研究表明:這種基于磁感應強度的超磁致伸縮材料的控制模型和控制方法,可有效地提高超磁致伸縮材料的控制精度;研制了具有驅動磁場和微位移感知功能的磁場與位移感知型超磁致伸微位移執行器,并提出了適用于此種執行器的設計理論和方法。

Photosynthesis and transpiration have no obvious difference between different age s . viciifolia , but they have consanguineous physiological responses to environmental factors such as photon flux density , air temperature and the content of soil water . compared with caraganar , s . viciifolia formed the physiological mechanics of less photosynthetic rate and less tranpiration rate to resist drought 狼牙刺的凈光合速率同光合有效輻射、大氣溫度和二氧化碳濃度之間沒有顯著相關性,與土壤含水量顯著正相關;蒸騰作用與光合有效輻射、土壤含水量及空氣溫度有很好的正相關性,與大氣濕度有負相關性。

The integral method is adopted caculate and analyze to amf three - dimension distruction which is the structure of coil type four - pole and the structure of coil type double - pole and study the size of two kind of electrode structure axial magnetic flux density distribution and its fielduniformity . the finite - element method is used simulate that eddy current has effect on amf when contact tray of douple - pole amf structure is slotted or no 本文采用積分方法對本文設計的線圈式兩極縱向磁場觸頭結構和線圈式四級縱向磁場觸頭結構的縱向磁場三維分布進行了計算分析。研究了電弧燃燒期間兩種觸頭結構縱向磁場強度的大小、均勻性,利用有限元法模擬線圈式兩極縱向磁場觸頭結構的觸頭盤開槽和不開槽時渦流對縱向磁場的影響。

And experimental study on the heat transfer performance and pressure drop characteristic of the process of bubbling evaporative cooling are carried . as there are so little attention and studies on the process bubbling evaporative cooling about heat transfer in the world at present , this paper mainly deals with the effects of the different bare tower velocity , weir height , heat flux density and plate perforation geometries on the heat transfer coefficient and the pressure drop of the process of air flowing 由于目前國內外對鼓泡蒸發冷卻過程在換熱方面的關注和研究較少,本文對不同空塔速度、不同堰高、不同熱流密度、多孔板的不同幾何尺寸對換熱系數及空氣流動過程阻力的影響進行了實驗研究及理論分析,總結了本實驗條件下換熱及阻力的實驗關聯式。

This test system can apply to two kinds of measurements . one is the automatic measurement of the core loss for the different core of the same type under the same amplitude of the magnetic flux density ; the other is the automatic measurement of the alternate magnetization curve and the core loss curve for the core 本測試系統主要進行以下兩方面的測試,一是在同一個b _ m下對同一型號的不同電機鐵芯進行鐵損測試;二是對電機鐵芯的交流磁化曲線和鐵損曲線的自動測試。

The interactions between heat flux density , vapor pressure , vapor velocity and the coefficient of heat transfer for condensation in tube , the coefficient of heat transfer in total are investigated . the relationships between heat flux density and the total difference in temperature , the difference of temperature , pressure drop of vapor from the entrance of the tube to the exit are investigated as well 考察了冷卻水流量、溫度恒定條件下熱流密度、蒸汽壓力、蒸汽流速對冷凝傳熱膜系數及總傳熱系數的影響關系,同時考察了總傳熱溫差、蒸汽進出口溫差及壓差隨熱流密度變化的關系。

By theoretical analysis and experimental investigation to the exasperate position of the heat transfer in the umbrella - plate falling film evaporator , the exasperate experimental formula of the heat transfer was obtained . with the same reynolds , the high - point heat flux density of umbrella - plate evaporator is higher than vertical - plate evaporator could be observed from above formula , which maked out that with little reynolds liquid film was not easy to break 在實驗條件下得出了傘板式降膜蒸發器小流量下液膜破裂的實驗關聯式,此關聯式表明極限熱通量隨臨界雷諾數增大而增大,在相同的臨界雷諾數下,傘板蒸發器的極限熱通量大于直板形蒸發器的極限熱通量。

The main achievements are as follows : the theory models of defect mfl field are set up ; based on the magnetic dipole model and finite element model , the distribution of defect mfl field is simulated in the dissertation ; the component of flux density ( magnetic filed ) parallel to the surface of pipe is detected by a circumferential array of hall probes ; the factors including defect geometry parameters , defect surface angle and shape , pipe material , field intensity , vehicle velocity , background magnetization , operating pressure and remanent magnetization and so on influence the mfl signal characteristics 采用霍爾元件作為缺陷漏磁檢測傳感器,獲得管道軸截面漏磁場切向分量的漏磁信號;研究了缺陷外形尺寸、缺陷傾角和形狀、管道材質和磁化強度、檢測儀移動速度、管道背底磁場、管內壓力和剩磁對漏磁信號的影響。提出了各通道增益放大、各路漏磁信號偏離調整、波形微分、數字濾波和平滑等漏磁信號預處理方法;分析了等空間采樣的漏磁信號轉換為等時間采樣信號的必要性,研究了漏磁信號的小波去噪方法。

However flux leakage is really exist , calculation through formular analytic method has more error , so electromagnetic field analysis is made by using finite element method ( fem ) in ansys7 . 1 / multiphysics and ansys / emag programs . typical quantities of interest in a magnetic analysis are available such as magnetic flux density , magnetic field intensity , magnetic forces , power loss and flux leakage in the system of magnetic levitation . then gain the current in the coil which control levitation gap when the stage is stable 由于存在漏磁,用公式的解析法計算有很大的誤差,因此本文采用有限元法( fem )來計算磁懸浮系統磁場分布,從而計算磁力,通過用ansys7 . 1軟件進行有限元電磁場分析計算,得到平臺穩定懸浮時電磁線圈所需電流、懸浮氣隙等控制參數,由于設計的磁懸浮系統為非軸對稱結構,采用2d磁場分析有一定的誤差,而采用3d電磁場分析更接近實際。

The hybrid claw - pole alternators have magnetic fields contributed by permanent magnet as well as excitation coil , and the advantages are high efficiency , have good low - speed characteristics , excitation adjustable and high flux densities . for the reason of complex claw - pole construction and 3 - d magnetic field distributions , there is lack of the research on the alternators 混合勵磁爪極發電機是由永磁體和勵磁線圈共同產生電機磁場的一種發電機,與傳統的爪極發電機相比有高效、低速性能好和集線圈勵磁的電壓調節性能與高磁通密度的優點,具有很好的研究前景和使用價值。

The results indicate that the qualitative behavior in this process is similar to that observed in condensation of vapor at or above atmosphere pressure , the coefficient of heat transfer for condensation in tube , the coefficient of heat transfer in total increase with the increasing of heat flux density and vapor pressure . however , heat flux density and vapor pressure have a more significant effect on them 發現水平管內低壓蒸汽冷凝過程與常壓條件下蒸汽冷凝過程相同,管內冷凝傳熱膜系數、總傳熱系數隨熱流密度、蒸汽壓力的增大而增大,但熱流密度、蒸汽壓力對低壓蒸汽冷凝有著更為顯著的影響,管外冷卻水流量對其影響并不明顯。

And the expression of magnetic flux density b is got by making use of the relation of magnetic vector potential a and magnetic flux density b . finally , the equation of the magnetic flux lines is given by way of describing the distributing of the magnetic field 通過求解該邊值問題得到了相應的矢量磁位a的解析表達式,然后利用矢量磁位a和磁感應強度召的關系求得了磁感應強度b的解析表達式。最后為了更直觀地描述磁場的分布給出了相應的磁力線方程。

In single magnet modeling , from the air gap magnetic - flux density , single magnet linear model which take the flux density as the state variable is obtained , and used the fitting formula which the magnetic field analysis had obtained to revise the model parameters 在對單鐵的建模中,從氣隙磁通密度的角度出發,得到了以磁通密度為狀態變量的單鐵線性模型,并采用磁場分析得出的擬合公式修正了模型參數。

The motor ' s magnetic field is analyzed with finite element method ( fem ) by ansys software . the emf and electro - magnetic torque are calculated with path method base on the air gap magnetic flux density ( b ) 運用有限元分析軟件ansys對電機內部磁場進行仿真分析,得出電機內部磁場磁密及磁場強度分布情況,在此基礎上運用路徑法對電樞反電動勢、電磁轉矩等電磁參數進行了分析計算。

Pms has no obvious relation to age and has good relation to air temperature , photon flux density and air humidity . the pre - dawn pms is steady . compared with caraganar , the drought - resistance ability of s . viciifolia is stronger 枝水勢同年齡之間無明顯關系,與環境因子間有很好的響應,同大氣溫度和光照顯著負相關,與大氣濕度顯著正相關。

Our factory ' s soft ferrite made from good - quality iron oxide has merits of high permeability , high saturation magnetic flux density and low loss , and id widely used in electric and electronic sets of various kinds 利用本公司優質氧化鐵生產的軟磁鐵氧體,具有高磁導率,高飽和磁通密度和低損耗的優點,它廣泛的用于各類電子電器整機中。

The iron core is used to maximize the coupling between the coils ( formed by conductors ) placed on the stator and rotor , to increase the flux density in the machine and to decrease the size of machine 鐵芯用于使放置在轉子和定子中的線圈(由導體構成)之間的耦合最大,以增加電機的磁通密度以及減小電機尺寸。

This test system can maintain the magnetic flux density ( 5 ) for sine wave automatically . so we need n ' t revise the testing data because of the distortion of the waveform 本測試系統可以實現自動保持磁感應強度b波形為正弦形,從而避免了對測試數據還要進行波形修正的麻煩,提高了測試的精度。