流速系數 的英文怎麼說
中文拼音 [liúsùxìshǔ]
流速系數
英文
coefficient of velocity- 流 : Ⅰ動1 (液體移動; 流動) flow 2 (移動不定) drift; move; wander 3 (流傳; 傳播) spread 4 (向壞...
- 速 : Ⅰ形容詞(迅速; 快) fast; rapid; quick; speedy Ⅱ名詞1 (速度) speed; velocity 2 (姓氏) a surna...
- 系 : 系動詞(打結; 扣) tie; fasten; do up; button up
- 數 : 數副詞(屢次) frequently; repeatedly
- 流速 : [機械工程] velocity of flow; strength; [水文] current velocity; current speed; flow rate流速管 pi...
- 系數 : [數學] coefficient; ratio; modulus; quotient; factor
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The additional flow is formed by the device of dentoid baffle, and the application of the device of dentoid baffle cooperated with a stilling basin has been investigated by systematic model tests. based on the research results, the hydraulic problems such as the characteristics of hydrodynamic pressure and cavitation on the head of the denotid baffle, the properties of flow under the condition that the device of denotid baffle is used with a stilling basin, the hydraulic computation about a stilling basin, the estimation of energy dissipation and its various affection factors, the mechanism and effect of energy dissipation, and distributions of velocity and pressure and aerating concentration, etc, have been analyzed ; the method and step of hydraulic design of device of denotid baffle by which the additional flow is produced has also been proposed
文中利用齒墩設施實現附加射流,對齒墩設施與消力池聯合應用進行了大量的和系統的模型試驗,分析研究了中低佛勞德數條件下,齒墩墩頭的動水壓強及空化特性,齒墩設施與消力池聯合應用時的流態特性,消力池的水力計算,消能量的估算及其各種影響因素,消能機理和效果,消力池內的流速、壓強特性,摻氣濃度分佈等水力學問題,並提出了實現附加射流齒墩設施的水力設計方法和步驟。The origins of dispersion error are analyzed ; effects of initial velocity dispersion, ballistic coefficient dispersion, drift coefficient dispersion, range wind & cross wind dispersion on the ballistic dispersion are discussed
分析了散布誤差的起源,討論了初速散布、射角散布、彈道系數散布、偏流散布、縱橫風散布對密集度的影響。The results of soil trough experiment indicated that, the flow velocity and froude number would add when the rainfall splash intensity rose ; the flow depth and resistance coefficient would decrease when the rainfall splash intensity increased
土槽試驗結果表明:土壤坡面薄層水流流速和弗汝德數隨雨滴打擊強度的增加而增加,水深、阻力系數隨雨滴打擊強度的增加而降低。Results show when velocity of flow remains unchanged in the onflow area and openness of the tube is changed, then resistance coefficient changes obviously
實驗結果表明:在湍流區域內流速(量)不變時,改變管件開度,阻力系數變化較顯著;改變流量,管件開度不變時,變化不大。In the positioning servo - system, which generally is configured by the d. c. pulse width modulator ( pwm ) velocity governing system and position servo - loop, the parameter perturbance of pwm velocity loop really exist by reason of such as the load behavior ; power voltage supply ; operating setting value, etc. 1, 2 , and it cannot be ignored. by using the identification technique to form the mathematical model of the system, authors have confirmed the facts. therefore, to design the discrete sliding mode controller ( dsmc ) of the positioning servo - system, the perturbed parameters value bounds of the pwm velocity loop, which is as the controlled plant of position servo - loop, should be accounted. consequently, the design principle of dsmc for accounting system with parameter perturbance is proposed by the authors. the proposed method can ensure the stability of system with parameter perturbance and the behavior of non - overshoot, fast precise positioning. in order to reveal the effects of the design method, the comparative research work is done by the authors. also, it has been tested in an industrial experiment, the results proved it is satisfactory
由直流脈寬調速系統( pwm )和位置環構成的定位系統中,速度環的參數隨負載特性;電網電壓;給定工況而攝動是不容忽視的.作者通過系統辨識建模也證實了這一事實1 , 2 .因此在設計位置環的離散滑模控制時,必須針對速度環(即位置環的控制對象)的參數攝動范圍採用「對象參數攝動離散滑模控制器的設計方法」 ,以確保系統在參數攝動時的穩定性和快速、無超調、準確定位的優良動態品質.為剖析該設計方法的控制效果,本文作了對比性研究,並將該設計方法用於工業試驗中,取得了滿意的結果At present, the typic harmful current detection methods are the fast fourier transform algorithm in frequency domain and methods based on the instantaneous reactive power theory, these methods all require some transform and quick, real - time calculating, so high precision analog multipliers or high speed dsp chip with fast a / d are needed, this results in complex circuit and high cost , which have restricted the development of apf
目前畸變電流檢測常用的方法有頻域法的fft和基於瞬時無功理論的畸變電流檢測法。這些方法均有一定的變換,需要快速、實時運算,因此必須使用高速的數字微處理器和高性能a / d轉換器,這必將大大提高系統成本,使得電路結構復雜,在一定程度上限制了有源濾波器的發展。Another based mathematics model about the anchor cable is used for ship - anchor system. the numerical calculation have been worked by programmed in the matlab language. at the same time the influence that the dragging speed of antisubmarine helicopter and the height over the surface of ocean acts on the shape and the tension of underwater cable, and that the current velocity and the diameter of anchor cable acts on the shape and the tension of anchor cable, has been calculated
把建立的水下拖索數學模型和錨索數學模型分別應用於航空吊放聲納探頭?纜繩動力學系統和船?錨系統,採用matlab語言編程進行了數值計算,同時分別計算和分析了反潛直升機拖速、距海面高度對拖索形狀和張力的影響以及海流速度、錨索直徑對錨索形狀和張力的影響。Evaluates and compares the workshop performance by velocity asymmetry coefficient ku, temperature asymmetry coefficient ki, the age of air, the temperature efficiency 77 and pmv - ppd index
廠房內的氣流組織採用速度不均勻系數k _ u 、溫度不均勻系數k _ t 、能量利用系數、空氣齡、 pmv - ppd指標進行綜合評價和對比。Results show that the influence of mainstream reynolds numbers on heat transfer coefficience is little and the heat transfer coefficience raise with the increase of reynolds numbers. the influence of the position of holes on heat transfer coefficience is complex and correlate with the mainstream speed and the balde surface curvature. and the influence of blowing ratio on heat transfer coefficience is more great ( especially to stator ), and show a complex relation to mainstream reynolds number and the position of holes
實驗結果表明,不同孔位出流的換熱由於孔排下游表面來流速度及葉片表面曲率的不同而有不同的規律,而主流雷諾數對葉片表面特別是壓力面和前緣區域的換熱系數比的影響較小,吹風比對換熱系數影響較大(特別是導葉) ,並且隨氣膜孔位置和來流雷諾數的變化而情況復雜。Three dimensional interaction flowfield over high - speed spinning projectile with lateral jets is numerically simulated in this dissertation firstly. complicated shocks wave patterns is analyzed. several factors concerned such as high - speed spinning, attack angle, base bleed and so on, are studied
本文首次完成了高速旋轉彈丸側噴三維干擾湍流流場的數值模擬,分析了彈丸側噴流場復雜的波系結構,研究了高速旋轉、攻角、底噴等因素對彈丸側噴流場的影響規律,深入分析了旋轉側噴彈丸的空氣動力學特性。The controller includes two control loops which are outer speed loop ( variable parameter pi adjustment ) and inner current loop ( single - chop current delta - control ). in order to improve system performances, design of digital control system based on dsp is presented. the proportional parameter and integral parameter can be obtained through the design
整個系統採用變pi參數轉速調節(外環)與單斬電流滯環調節(內環)相結合的雙閉環控制方式,為了得到既快速又穩定的恆速系統,本文還給出了基於dsp的雙凸極永磁電機數字控制系統的設計方案,通過此設計方案可以得到轉速環的比例參數kp和積分參數ki的參考值。In chapter four, according to the analysis on the boundary theory and velocity field of main fluid zone of two - phase fluid pumps, the parameter equations of vane ' s modular curve of centrifugal pump are given, which contact the boundary " layer and eular theory of two - phase fluid pump by the fixing angel of vane as variable and leading into the velocity coefficient a. the results show that, in designing process of vane ' s modular curve of centrifugal pump, the determination of the total shape and parameters relates the flow properties of two - phase fluid and output ability of pump, or the design of the modular curve of centrifugal pump is the kernel of hydraulic design
第四章依據固液兩相流泵的邊界層理論及對主流區速度場的分析,給出了離心泵葉片型線的參數方程;它是以葉片安裝角為參變數,以引入的速度系數k _ v作為中間因子,將兩相流泵的邊界層理論和歐拉理論聯系起來? ?它說明了這樣一個事實,在離心泵葉片型線的設計過程中,它的整個形態或參數的確定都關繫到兩相流體的流動特性和泵的輸出能力,或者說,離心泵型線的設計是其水力設計的核心。On the basis of these results, the relations of total - pressure recovery coefficient or flow coefficient and flight mach number, angle of attack and the second movable wedge angle of the inlet have been founded by hypersurface fitting, then the mathematical model of the inlet is established
根據流場計算結果並利用超曲面擬合方法建立了進氣道總壓恢復系數、流量系數與飛行馬赫數、進氣道攻角及二級可調斜板角度之間的關系,由此得到了二元混壓式超聲速進氣道數學模型。( 2 ) on the leading edge, the film cooling effectiveness at the zone immediately downstream of the cooling holes is affected by blowing ratio and mainstream reynolds number, while the effects are not important in the downstream zone far from the cooling holes. ( 3 ) on the front half of pressure surface, the effectiveness increases with decreasing blowing ratio at the downstream near the cooling row and it is contrary at the downstream far from the cooling row. ( 4 ) on the rear pare of the pressure surface, the effectiveness decreases with increasing blowing ratio and does not vary so much downstream in the cases of higher blowing ratio
研究結果表明葉片吸力面端壁附近區域壓力系數分佈呈現出較強的三維特性,動葉吸力面尤其明顯;氣膜孔流量系數隨吹風比的增加而增大,在高吹風比情況下,流量系數逐漸趨于常數;在不同型面區域,冷卻效率分佈有較大的差異,而且吹風比與主流雷諾數的影響程度也不盡相同;低吹風比下,孔出口下游附近可以得到較好的冷卻,中、高吹風比下,冷氣射流在加速流動主流的作用下返回壁面進行二次冷卻,孔下游較遠區域可以得到較好的冷氣覆蓋。The comparison of the calculation formula for unsteady jet flow with that of steady jet flow demonstrates that the pulse frequency is the main factor influencing the velocity coefficients 2 and 5, and the relationship between the velocity coefficients of pulsed jet flow and steady jet flow was revealed
通過與恆定射流的流速系數計算式對比,闡明了脈沖頻率是影響2和5的主要因素,溝通了脈沖射流與恆定射流流速系數之間的關系。The calculation formulas for velocity coefficients 2 and 5 for the throat and throat inlet section were deduced from the theoretical research on the velocity coefficients in time - averaged basic equations by use of the unsteady momentum equation and time - averaged value calculation method
摘要運用非恆定的動量方程和時均值計算方法,對脈沖液體射流泵時均值基本方程中的流速系數進行了理論研究,推導出了喉管和喉管進口段流速系數2和5的計算式。Loading grads is another non - structure coefficient influencing loading characteristics except loading frequency. the low grads characteristics are analyzed deeply by simulation, and found that applying structure invariance principle with acceleration compensation can reduce loading grads effectively. the dissertation also simulates and compares the systems with connect hole of different size, and founds that the size of connect hole has an optimized value
加載梯度是除了加載頻率之外另一個影響加載性能的非結構上的參數,論文作了大量的模擬分析來研究小梯度加載特性,得出了具有加速度補償的結構不變性原理可以有效的降低小加載梯度時的多餘力矩的影響;通過對具有不同的總壓力流量系數的系統的模擬比較,得出了連通孔的大小在不同工況下存在一個最優的值,其開度需要合理的選擇。The differential pressure across the pressure test points is measured and the flow rate calculated using the calibrated chart or flow coefficient table
測量經過壓力測試點的壓差,並利用標準化圖表或流量系數表計算流動速率。The relevance functions between total pressure recover coefficient and the parameters ( mach number, angle of attack, flow coefficient, angle of sideslip ) for subsonic submerged inlet in turbojet and turbofan engine were investigated
摘要根據某埋入式進氣道試驗數據建立了計算埋入式亞聲速進氣道總壓恢復系數的經驗公式,表現為關于馬赫數、流量系數、攻角、側滑角的函數。As a general rule, an adequately sized globe valve ( i. e. with pipe velocity between 15 to 25 ft / sec for water and 200 to 300 ft / sec for steam ) should not be throttled down below 35 % of its maximum full open cv capacity ( approximately 20 % of full stroke )
一般而言,通徑足夠大的截止閥(例如管道內水流速度在15至25英尺/秒之間,蒸汽流速在200至300英尺/秒之間) ,節流后的流量不應該小於完全開啟狀態流量(流量系數大約為全沖程的20 % )的35 %以下。分享友人