水壓損失 的英文怎麼說
中文拼音 [shuǐyāsǔnshī]
水壓損失
英文
head loss-
Abstract : this paper analyzes causal factors of flood in the middle reaches of changjiang river. due to neglection of environmental management, soil erosion in the upper and middle reaches of the changjiag river, lake sedimentation, large - scale reclamation of marshes, the flood regulation capacity of the lake was descended, and flood stage was risen and prolonged. consequently more and more river levees and lake dikes were reinforced almost every year to prevent the disasters, which made flood level go up and flood period last for more days. the frequency of flood and waterlogging disasters rose and their damage was enlarged. several proposals for flood prevention including agricultural modernization are put forward
文摘: 1998年長江大洪水后開始實施的「平垸行洪,退田還湖」的土地利用調整方案,從長遠來說應尋求農業安全且收入逐漸提高條件下的土地利用,長江中游地區應積極推進農業現代化,提高農業勞動生產率,轉移,減少分蓄洪區的人口,移民建鎮,對區內的土地要促進其規模經營,由優秀的有文化的農民經營,平時只有少量的直接從事農業生產的經營管理人員,農忙時則大量地使用季節性合同工或實現機械化,大洪水時退田還湖,減輕長江幹流大洪水的壓力,減少分洪與特大洪災時的損失,這樣還可促進避洪、冬季農業等的發展,也有利於長江中上游地區陡坡耕地的退耕還林,還可在糧食充足時進行休耕,在旱災、糧食緊張時擴大糧食生產?2. based on the results of experimental data of the tailrace surge tank of yi xing pumped - storage station in jiangsu province, this research investigates the methods for the head loss coefficients of throttled surge tank with linking pipe by means of the method which incorporates experimental results with theoretical analysis
結合江蘇宜興抽水蓄能電站尾水調壓室水力模型試驗成果,採用理論計算與模型試驗結果相結合的方法,對有連接管的阻抗式調壓室局部水頭損失系數的計算方法進行了討論。The impacts of both the velocity head and momentum distribution in the t - junction of a tailrace surge tank on the critical stable sectional area of the tank were analyzed by using gardel ' s empirical equations for t - junction flow. based on thoma ' s theory, a formula of the critical stable sectional area is derived. 5
基於gardel關於三通管水頭損失的經驗公式,研究分析了連接管處的速度水頭以及進出調壓室水體與尾水隧洞水體之間的動量交換,對有連接管的尾水調壓室穩定斷面積的影響,並在托馬( thoma )假定基礎上,推導出相應的調壓室穩定斷面的計算公式; 5( 4 ) through the hydraulic property experiment of micro - hole lateral pipes of simple sdi in air, it was found that the average pressure of 60 mitre length lateral pipes was at the position of per 40o / o ~ ~ ~ 50 % of the effectual pipe length from the fist micro - hole, major pressure - loss was occurred at the ahead part of half pipe. the pressure uniformity reduced with orifice aperture ? increasing, and the relationship between pressure uniformity and initial water pressure was poor. running under the initial water pressure of 1. 5 meter, the discharge uniformity reduced with orifice aperture ? increasing, and when the orifice aperture smaller than or equal 1. 0mm, irrigation uniformity could achieve above 0. 6
( 3 )通過對空氣介質中簡易地下滴灌的微孔毛管試驗研究發現: 60m管長的毛管平均壓力水頭的位置基本上在距第一孔口的有效管長40 - 45的地方;大部分水頭損失發生在毛管的前半部分;壓力均勻度隨孔徑的增大而減小,但與初始工作水頭關系不密切;在1 . 5m以下的工作壓力下運行,沿程出流均勻度隨孔徑的增大而降低,當孔徑不大於1 . 0mm時,灌水均勻度可以達到60以上;當孔徑大於等於1 . 2mm時,灌水均勻度低於50 。In this paper, high heat penetration into a moving particulate bed is described mathematically with a comprehensive heat and mass transfer model. the distribution of gas velocity and pressure, the temperature field of gas and solid in the moving particulate bed are examined for different conditions. the results show that thermal penetration into the moving packed - bed particles by fluid flow in porous media is high only in the position near the gas entrance. the thermal penetration thickness tends to increase with the fluid flow velocity and decrease with the particle moving velocity. in the region of thermal penetration, the porosity of solid bed has significant effect on gas field and pressure loss. it is feasible to reduce the gas pressure loss by a larger width / height packed bed in design and operation. the correspondence between thermal infection depth and particle bed height would be helpful to keep high oapacity of reactor and reduce the cost of operation
針對移動顆粒床中物料層內的高溫氣體滲流傳熱現象,考慮滲流與傳熱的相互作用,採用局部非熱平衡假設建立了多孔介質滲流傳熱物理數學模型並進行了數值計算.研究了不同情況下床內填充多孔介質中的流速、氣固溫度和床層壓力損失.計算結果表明,高溫熱氣對移動床顆粒料層的熱滲透主要發生在滲流入口端區域,增大入口滲流速度以及減小床層物料下移速度將導致物料溫度沿床高慢速下降,熱滲透深度擴大,熱滲透作用區域內的物料溫度水平提高.在熱滲透作用區域,孔隙率對流場和壓力損失有很大的影響.研究結果對于移動顆粒床反應器的設計與運行具有一定的參考作用The centrifugal pump for oilfield waterflooding and oil transfer worked with low pump efficiency owing to unstable load and its energy loss is fairly large
油田注水集輸系統離心泵由於載荷經常變化,大多不能在其額定工況點工作,泵效低,且需要用泵出口閥調節流量,產生一定的泵管壓差,造成較大的能量損失。Based on the method of energy consumption, an analysis is given of the impact, which the dirt growth of a tube and shell sewage heat exchanger will have on transfer intensity, flow pressure drop and their energy losses
本文運用熱力學能耗分析法,分析了管殼式污水換熱器中軟垢的厚度對換熱強度、流動壓降及其有效能損失的影響。The result indicates that the designed pressure loss of water systems is large among various loops for different air conditioning system zones
結果表明,對應建築不同使用功能的空調系統分區,其水系統各支路之間設計壓力損失相差較大。The open angle, head loss and hydrodynamic pressure under the rated flow and several kinds of proportion are carefully observed in the model test, and these results are given for reference in engineering design
階段模型試驗中詳細觀測了在額定流量下,不同比重拍門的開啟角度,水頭損失及門體動水壓力變化情況,以供工程設計應用參考。The one - piece impeller can effectively reduce the by - pass loss, friction loss, etc. and improve the efficiency of the compressor as well as the performance of the diesel engine
新型號的葉輪能有效減少分流損失、潛流損失、摩擦損失、鼓風環流等損失,能有效提高壓氣機的效率、柴油機的性能水平,改善經濟運營指標。The main achievements are as follows : it is verified that there is an unique mean square solution to the stochastic surge model ; the formulas for probability density function of head loss and the maximum relative surge level were deduced ; the joint probability density function for solving surge process and the mean head process of simple hydraulic system were also derived
主要研究成果有:證明了調壓室涌浪隨機模型存在唯一的均方解;推導出了水頭損失和最大相對涌浪值的密度函數計算公式;求解了調壓室涌浪解過程的聯合密度函數和簡單水力系統的水頭均值過程等。In this paper according to the design scheme of yao heba power station in nan yahe river, the mathematical model with longer and complicated conduit system, elastic water hammer and pid regulating low of voter turbine adjusting system in the case of the small fluctuation has being built, which include conduit system, surge tank, draft tube, water turbine, generator and governor. the hydraulic losses are taken into account, and nonlinearization in water turbine and the governor is also taken into account
本文根據南椏河姚河壩水電站的設計方案,對水輪機調節系統,按長引水管道復雜引水系統、彈性水擊、調速器為pid調節規律,在小波動情況下,對包括引水道、調壓井、尾水管、水輪機、發電機、調速器在內的水輪機調節系統建立數學模型,並計及引水管道水力摩阻損失,對水輪機、調速器考慮了其中的非線性,利用功能強大的matlab軟體編制了源程序進行計算機模擬計算。It is more accurate than traditional method at the aspect of calculating head loss, pipe flow and node pressure of hydrant. this mathematic model can also be used in the inside and outside of water supply piping calculation and it is excel hardy cross - piping calculation
該方法在計算水頭損失、管段流量、消火栓節點壓力等方面比傳統方法要更加準確,也可被借鑒到室內或室外的給水管網計算,並優于常見的哈代-克羅斯管網平差方法。Corresponding to the correct water hammer mathematic model ( 3 ), the character difference equation is by comparing the new mathematic model with the old mathematic model, the last calculative part of paper argues the falseness of the current water hammer mathematic model, makes use of the improved character line method to analyze the correct mathematic model ( 3 ), studies all kinds of facts " impact on water hammer pressure value and water hammer phenomenon attenuation, points out that, in the long pipeline system, the subarea calculation of head loss along with flow rather influences the calculative results of water hammer pressure, advices to take the subarea calculation of head loss along with flow into account in the water hammer calculation of the long pipeline system
對應于正確的水擊數學模型( 3 )的特徵差分方程形式如下c ,弓+吼川一c ,唱一幾弓扮幾rv另卜川= o幾代+吼川一幾唱一吼嶸{一c :腳丸}唱} ? 「本論文在最後的計算部分,通過對新老數學模型的數值計算比較,進一步論證了當前水擊數學模型的不正確性。並且應用改善了的特徵線法對正確的數學模型( 3 )進行了計算分析,研究了各種因素對水擊壓強值和水擊現象衰減的影響,指出在長管道系統中,沿程水頭損失的分區計算對水擊壓強的計算結果影響較大,建議在長管道系統的水擊計算中應按分區進行沿程水頭損失的計算。With the in - built drip irrigation belt and thin wall chip irrigation belt taken as examples, the flow rate distribution and hydraulic losses of drippers along capillary tubes at different inlet pressures were measured under the conditions of horizontal slope and slope gradients of 0. 5 % and 1 %, then the uniformity of capillary tubes was calculated at different slope gradients and pressures in consideration of the manufacture deviation of drippers
摘要以內鑲式滴灌帶和薄壁滴灌帶為研究對象,測定了平坡、 0 . 5 %坡度和1 %坡度時,不同入口壓力下滴頭沿毛管的流量分佈和水力損失,並結合滴頭的製造偏差,計算得出不同坡度和壓力條件下滴灌毛管的均勻度。Based on the principle of hydraulics, the general equation for head loss and the formula for calculation of pressure head along the flexible hoses were worked out, and the method for determination of the maximum and minimum heads and their positions was given
摘要根據水力學原理建立了軟管沿程水頭損失的一般方程,得出了軟管沿程壓力水頭的計算公式,給出了確定最大和最小壓力水頭位置及大小的方法,從計算結果與試驗實測結果的對比看,具有一定的合理性。Ulteriorly, considering the local head loss in inlet opening and pipes junction plays more important role in the calculative results of water hammer pressure calculation of the short pipeline system
考慮進口及多管道連接處的局部水頭損失對短管道系統水擊壓強的計算結果影響較大。In this article, through lab and engineering site trials that the physical data of new type pipe materials is corrected, the results are as follow : ( l ) the expansion coefficient of new plastic pipe materials is more large than that of iron pipe. ( 2 ) new plastic pipe materials have different heat - resisting character and according to the water temperature to choose pipe materials ; ( 3 ) the loss of head of water for new type pipe materials is more smaller than iron pipe and also correct the loss of head of water that calculated by theory ; ( 4 ) probing into the press - resistance character of new plastic pipe materials
本文通過試驗室試驗及工程現場試驗,對新型給排水管材的幾個重要的物理性能參數進行實驗測定,糾正了以往的錯誤認識。研究結果表明: ( 1 )新型塑料管材線脹系數遠遠大於鋼管和鑄鐵管,設計和施工中要嚴格考慮管道的伸縮; ( 2 )新型塑料管材耐高溫性能各不相同,需根據管內水溫選定管材; ( 3 )新型管材水頭損失遠小於鋼管,並對原水頭損失計算公式進行了修正; ( 4 )對于塑料管材的耐壓性能進行了探討。The mathematical analysis shows that, with disregarding local head losses and by means of different simplified rigid models, the calculated results of the maximum pressure in a pressurized pipe system containing trapped air mass are equal to and independent of the initial length of the water - column
摘要通過數學分析證明,在不計局部水頭損失時,目前常用的幾種簡化剛性數學模型的最大氣壓計算結果相等,並與管道內初始充水段長度無關。Based on the head loss coefficients obtained from gardel ' s semi - empirical equations for t - junction flow and experiment of welded t - junction, the hydraulic characteristics of throttled surge tank are estimated and compared with those gotten from hydraulic experiment. 3. four different methods of determining the head loss coefficients of throttled surge tank have been employed to investigate the effect of methods afore mentioned on the accuracy of calculating surge and pressure head of throttled surge tank
給出了基於gardel關於三通管水頭損失系數的經驗公式、焊接t形三通管水頭損失系數的實驗資料及截面突變管道的水頭損失資料,計算有連接管的阻抗式調壓室在不同流態下水頭損失系數的計算方法,並將這兩種方法計算得到的調壓室局部水頭損失系數分別與模型試驗成果進行了比較和分析; 3分享友人