管流阻力系數 的英文怎麼說
中文拼音 [guǎnliúzǔlìxìshǔ]
管流阻力系數
英文
pipe resistance coefficient- 管 : Ⅰ名詞1 (管子) pipe; tube 2 (吹奏的樂器) wind musical instrument 3 (形狀似管的電器件) valve;...
- 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...
- 阻 : 動詞(阻擋; 阻礙) block; hinder; impede; obstruct
- 力 : Ⅰ名1 (力量; 能力) power; strength; ability; capacity 2 [物理學] (改變物體運動狀態的作用) forc...
- 系 : 系動詞(打結; 扣) tie; fasten; do up; button up
- 數 : 數副詞(屢次) frequently; repeatedly
- 管流 : capillary flow
- 阻力 : 1 (阻礙事物發展的外力) obstruction; resistance 2 [物理學] resistance; drag; drag force; nowel; ...
- 系數 : [數學] coefficient; ratio; modulus; quotient; factor
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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。Aiming at the study actuality of fan performance monitoring system and analysis of fan performance curve changes affected by inlet - box and the different fixed - angles of guide blades in the course of installation, a fan flow monitoring model based on rbfnn in whole flow zone was established in this thesis. in the model, the method of no throttle and fan performance curve were used as basis. and on the basis of that model, fan performance curves of 4 - 73no. 8d were approached with experimental data of different speed, different opening - angles of guide blade and different resistance of pipeline, the precision and the error law of model were studied
本文針對電站風機性能監測系統研究較少的現狀,在實驗的基礎上分析了現場加裝進氣箱和由於安裝造成的導流器葉片開度不一致對風機性能曲線的影響,並在此基礎上採用無節流方法測量流量,以風機調節性能曲線為依據,建立了基於徑向基函數( rbf )神經網路的風機流量全程監測模型;以實驗室4 - 73no . 8d離心風機為研究對象,探討了rbf神經網路差壓模型在變轉速、變導流器開度和變管網阻力等工況下的應用精度和誤差分佈規律;最後用visualc + +語言開發了風機性能在線監測系統。After thermodynamic calculation on several operation conditions of the furnace, cold - state flow and resistance mensuration, the combustion of the tubular - furnace hearth was changed into swirl and addition of radiate cylinder and oxygen content detection minish 1. 25 surplus air to less than 1. 15, improving the combustion condition and convection and radiate heat transfer efficacy, resuling in reducing the waste - gas temperature 45, decreasing exhaust gas loss, and saving fuel by 6 %
摘要通過對加熱爐幾種工況進行熱力計算、冷態試驗的流場分佈及阻力測定和熱態試驗的爐膛溫度場分佈及管壁溫度等參數的測定,確定將管式加熱爐爐膛內直流燃燒改為旋流場燃燒和增加輻射筒,增設煙氣含氧量分析,可以將燃燒的過剩空氣系數從1 . 35減小到1 . 15以下,極好地改善爐膛內的燃燒狀況和對流輻射傳熱效果,從而降低排煙溫度45 ,減少加熱爐排煙損失,節約了煤氣量6 %以上。Fluid network was divided into a lot of independent loops. through changing states of valves, i got pipe flux and pipe pressure drop. based on pressure balance equation, i built the differential equation system, solved the differential equation system, and acquired resistance coefficients of pipes and component
並將流體網路圖分解為一個個獨立迴路,通過改變閥門的狀態,來獲取迴路各管段流量和壓力損失,根據迴路壓力平衡方程,建立方程組,對方程組進行了求解,解出了各未知管段、流體器件的阻力系數。The experimental results of the flow characteristics of the mmc heat sink indicate that the critical reynolds number signifying the transition from laminar flow to turbulent flow is in advance ; under the same experimental conditions, the variation in entrance direction of the microchannel inlet and outlet has little effect on the microchannel ; the experimental values of the friction factor of the de - ionized water in a microchannel agree well with those calculated using the theoretical laminar formula ; furthermore, a comparison of the experimental results and simulation results shows that navier - stokes equation and rng - turbulence model can be used to model the laminar and turbulence flow regions in a microchannel ; meanwhile, the correlations of the flow resistance in the turbulent flow regions for the de - ionized water as the working fluids are obtained from experiments
對歧管式單通道熱沉流動特性的研究結果表明,微通道內流體流態由層流向紊流轉變的臨界雷諾數提前;改變流體的進出口方向對熱沉總壓降造成的影響很小;摩擦系數的實驗值與理論值較接近;數值模擬結果能夠與實驗值較好吻合;並由實驗給出了紊流區流動阻力的實驗關聯式。此外,選用十二烷基硫酸鈉( sodiumdodecylsulphate , sds )以及烷基多糖苷( alkylpolyglycoside , apg )作為減阻添加劑,研究了表面活性劑添加對微通道流動特性的影響。6th, wear resistant, pipe wall friction coefficient low, the resistance to flow is small, delivery capacity
6耐磨性強,管壁摩擦系數低,流阻小,輸送能力強By use of grid - shaping skill and multi - grid solver, the flow - induced vibration of the fluid - conveying pipe in water is studied. the vibration mechanism of the fluid - conveying pipe in water is analyzed, the lift and drag acting on pipe in water are calculated. the results obtained are analyzed and compared to the experimental data referred to
首先對水下輸液管道繞流渦激振動的機理進行了分析,然後,利用網格生成技術及多重網格法求得了輸液管道在不同來流條件(雷諾數)下的橫向升力系數及縱向阻力系數,最後對計算結果進行了分析,並將其與已有的間接實驗結果進行了對比。A novel strip - coil - baffle structure used to enhance heat transfer and support the tube bundle for a tube - shell heat exchanger is proposed. the new structure can sleeve the tubes in bundle alternatively to create a vortex flow in a heat exchanger. the numerical simulation on the flow and heat transfer characteristics for this new structure heat exchanger is conducted. the computational domain consists of two strip - coil sleeved tubes and two bare tubes oppositely placed at each corner of a square. the velocity and temperature fields in such strip - coil - baffled channel are simulated using fluent software. the effects of the strip - coil - baffles on heat transfer enhancement and flow resistance in relation to the reynolds number are analyzed. the results show that this new structure bundle can enhance the heat transfer coefficient up to a range of 40 ? to 55 ? in comparison with a bare tube bundle ; meanwhile, higher flow resistance is also accompanied. it is believe that the strip - coil - baffled heat exchanger should have promising applications in many industry fields
介紹了一種用於強化管殼式換熱器殼側傳熱和支撐管束的螺旋折流片新型結構,該結構是對換熱器管子相間地套上螺旋折流片以產生旋渦流動.研究模型是在正方形布置的4個管子中的2個對角管子套上螺旋折流片后形成的通道,利用fluent軟體對該上述四管通道模型的流場和溫度分佈情況進行了數值模擬;分析了四管通道模型中螺旋折流片對強化傳熱和流動阻力隨雷諾數的變化關系的影響.算例結果顯示該新型結構可比相同尺寸的光管通道中的情形傳熱系數提高約40 ? 55 ? ,同時也將伴隨較高的流動阻力.可以相信螺旋折流片式換熱器將會在許多工業領域有良好的應用前景Abstract : a novel strip - coil - baffle structure used to enhance heat transfer and support the tube bundle for a tube - shell heat exchanger is proposed. the new structure can sleeve the tubes in bundle alternatively to create a vortex flow in a heat exchanger. the numerical simulation on the flow and heat transfer characteristics for this new structure heat exchanger is conducted. the computational domain consists of two strip - coil sleeved tubes and two bare tubes oppositely placed at each corner of a square. the velocity and temperature fields in such strip - coil - baffled channel are simulated using fluent software. the effects of the strip - coil - baffles on heat transfer enhancement and flow resistance in relation to the reynolds number are analyzed. the results show that this new structure bundle can enhance the heat transfer coefficient up to a range of 40 ? to 55 ? in comparison with a bare tube bundle ; meanwhile, higher flow resistance is also accompanied. it is believe that the strip - coil - baffled heat exchanger should have promising applications in many industry fields
文摘:介紹了一種用於強化管殼式換熱器殼側傳熱和支撐管束的螺旋折流片新型結構,該結構是對換熱器管子相間地套上螺旋折流片以產生旋渦流動.研究模型是在正方形布置的4個管子中的2個對角管子套上螺旋折流片后形成的通道,利用fluent軟體對該上述四管通道模型的流場和溫度分佈情況進行了數值模擬;分析了四管通道模型中螺旋折流片對強化傳熱和流動阻力隨雷諾數的變化關系的影響.算例結果顯示該新型結構可比相同尺寸的光管通道中的情形傳熱系數提高約40 ? 55 ? ,同時也將伴隨較高的流動阻力.可以相信螺旋折流片式換熱器將會在許多工業領域有良好的應用前景Taking some tubular air pre - heater used in one boiler whose capacity is 130 t / h as an example, new blue print with inner trachea is completed by means of computer program. several key design variables may be changed, such as diameter of pipe and velocity of flow of gas. these cases have been considered, and their results have also been compared with each other
比較了幾個重要的設計變量,如外管徑、煙氣流速等參數變化時,總傳熱系數和空預器本體管子總重量,阻力損失以及最低管壁溫度等幾個重要設計結果的變化趨勢,對內螺紋管空氣預熱器的設計具有借鑒意義;其間還分析了內螺紋管與光管在設計時的不同之處;最後,初步分析了內螺紋管的優化設計問題,提出了一些建議。( 2 ) the flaws on the one - dimension ( 1 - d ) compressible isothermal average - friction - factor were indicated. a friction factor computation method was proposed, which is not only suitable for compressible flow but also easy to achieve the average wall shear stress
( 2 )指出關于微管道內已有的一維可壓縮等溫流動的平均阻力系數確定方法的不足之處,並提出了一種便於實用的可壓縮流動平均阻力系數的確定方法。Since frosting is inevitable so long as some physical factors are satisfied, it will enlarge the resistance of airflow, cut down the airflow rate of air cooler and reduce the coefficient of heat transfer. in order to keep the refrigeration system run smoothly, frost must be removed
結霜只要滿足一定的物理條件就是不可避免的,霜層增厚增加了空氣的流動阻力,冷風機盤管流量減少,同時霜層增厚也會導致傳熱系數下降,因此為保持系統高效運行,除霜是必須的。分享友人